OpenCloudOS-Kernel/fs/cifs/connect.c

4322 lines
114 KiB
C
Raw Normal View History

// SPDX-License-Identifier: LGPL-2.1
/*
*
* Copyright (C) International Business Machines Corp., 2002,2011
* Author(s): Steve French (sfrench@us.ibm.com)
*
*/
#include <linux/fs.h>
#include <linux/net.h>
#include <linux/string.h>
#include <linux/sched/mm.h>
#include <linux/sched/signal.h>
#include <linux/list.h>
#include <linux/wait.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/ctype.h>
#include <linux/utsname.h>
#include <linux/mempool.h>
#include <linux/delay.h>
#include <linux/completion.h>
#include <linux/kthread.h>
#include <linux/pagevec.h>
#include <linux/freezer.h>
#include <linux/namei.h>
#include <linux/uuid.h>
#include <linux/uaccess.h>
#include <asm/processor.h>
#include <linux/inet.h>
#include <linux/module.h>
#include <keys/user-type.h>
#include <net/ipv6.h>
#include <linux/parser.h>
#include <linux/bvec.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "ntlmssp.h"
#include "nterr.h"
#include "rfc1002pdu.h"
#include "fscache.h"
#include "smb2proto.h"
#include "smbdirect.h"
#include "dns_resolve.h"
#ifdef CONFIG_CIFS_DFS_UPCALL
#include "dfs_cache.h"
#endif
#include "fs_context.h"
#include "cifs_swn.h"
extern mempool_t *cifs_req_poolp;
extern bool disable_legacy_dialects;
/* FIXME: should these be tunable? */
#define TLINK_ERROR_EXPIRE (1 * HZ)
#define TLINK_IDLE_EXPIRE (600 * HZ)
/* Drop the connection to not overload the server */
#define NUM_STATUS_IO_TIMEOUT 5
struct mount_ctx {
struct cifs_sb_info *cifs_sb;
struct smb3_fs_context *fs_ctx;
unsigned int xid;
struct TCP_Server_Info *server;
struct cifs_ses *ses;
struct cifs_tcon *tcon;
#ifdef CONFIG_CIFS_DFS_UPCALL
struct cifs_ses *root_ses;
uuid_t mount_id;
char *origin_fullpath, *leaf_fullpath;
#endif
};
static int ip_connect(struct TCP_Server_Info *server);
static int generic_ip_connect(struct TCP_Server_Info *server);
static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
static void cifs_prune_tlinks(struct work_struct *work);
/*
* Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
* get their ip addresses changed at some point.
*
* This should be called with server->srv_mutex held.
*/
static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
{
int rc;
int len;
char *unc, *ipaddr = NULL;
time64_t expiry, now;
unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;
if (!server->hostname)
return -EINVAL;
len = strlen(server->hostname) + 3;
unc = kmalloc(len, GFP_KERNEL);
if (!unc) {
cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
return -ENOMEM;
}
scnprintf(unc, len, "\\\\%s", server->hostname);
rc = dns_resolve_server_name_to_ip(unc, &ipaddr, &expiry);
kfree(unc);
if (rc < 0) {
cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
__func__, server->hostname, rc);
goto requeue_resolve;
}
spin_lock(&cifs_tcp_ses_lock);
rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
strlen(ipaddr));
spin_unlock(&cifs_tcp_ses_lock);
kfree(ipaddr);
/* rc == 1 means success here */
if (rc) {
now = ktime_get_real_seconds();
if (expiry && expiry > now)
/*
* To make sure we don't use the cached entry, retry 1s
* after expiry.
*/
ttl = max_t(unsigned long, expiry - now, SMB_DNS_RESOLVE_INTERVAL_MIN) + 1;
}
rc = !rc ? -1 : 0;
requeue_resolve:
cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
__func__, ttl);
mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));
return rc;
}
static void cifs_resolve_server(struct work_struct *work)
{
int rc;
struct TCP_Server_Info *server = container_of(work,
struct TCP_Server_Info, resolve.work);
mutex_lock(&server->srv_mutex);
/*
* Resolve the hostname again to make sure that IP address is up-to-date.
*/
rc = reconn_set_ipaddr_from_hostname(server);
if (rc) {
cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
__func__, rc);
}
mutex_unlock(&server->srv_mutex);
}
/**
* Mark all sessions and tcons for reconnect.
*
* @server needs to be previously set to CifsNeedReconnect.
*/
static void cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server)
{
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct mid_q_entry *mid, *nmid;
struct list_head retry_list;
server->maxBuf = 0;
server->max_read = 0;
cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
trace_smb3_reconnect(server->CurrentMid, server->conn_id, server->hostname);
/*
* before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
* are not used until reconnected.
*/
cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n", __func__);
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
ses->need_reconnect = true;
list_for_each_entry(tcon, &ses->tcon_list, tcon_list)
tcon->need_reconnect = true;
if (ses->tcon_ipc)
ses->tcon_ipc->need_reconnect = true;
}
spin_unlock(&cifs_tcp_ses_lock);
/* do not want to be sending data on a socket we are freeing */
cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
mutex_lock(&server->srv_mutex);
if (server->ssocket) {
cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
server->ssocket->flags);
kernel_sock_shutdown(server->ssocket, SHUT_WR);
cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
server->ssocket->flags);
sock_release(server->ssocket);
server->ssocket = NULL;
}
server->sequence_number = 0;
server->session_estab = false;
kfree(server->session_key.response);
server->session_key.response = NULL;
server->session_key.len = 0;
server->lstrp = jiffies;
/* mark submitted MIDs for retry and issue callback */
INIT_LIST_HEAD(&retry_list);
cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
spin_lock(&GlobalMid_Lock);
list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
kref_get(&mid->refcount);
if (mid->mid_state == MID_REQUEST_SUBMITTED)
mid->mid_state = MID_RETRY_NEEDED;
list_move(&mid->qhead, &retry_list);
mid->mid_flags |= MID_DELETED;
}
spin_unlock(&GlobalMid_Lock);
mutex_unlock(&server->srv_mutex);
cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
list_del_init(&mid->qhead);
mid->callback(mid);
cifs_mid_q_entry_release(mid);
}
if (cifs_rdma_enabled(server)) {
mutex_lock(&server->srv_mutex);
smbd_destroy(server);
mutex_unlock(&server->srv_mutex);
}
}
static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
{
spin_lock(&GlobalMid_Lock);
server->nr_targets = num_targets;
if (server->tcpStatus == CifsExiting) {
/* the demux thread will exit normally next time through the loop */
spin_unlock(&GlobalMid_Lock);
wake_up(&server->response_q);
return false;
}
server->tcpStatus = CifsNeedReconnect;
spin_unlock(&GlobalMid_Lock);
return true;
}
/*
* cifs tcp session reconnection
*
* mark tcp session as reconnecting so temporarily locked
* mark all smb sessions as reconnecting for tcp session
* reconnect tcp session
* wake up waiters on reconnection? - (not needed currently)
*/
static int __cifs_reconnect(struct TCP_Server_Info *server)
{
int rc = 0;
if (!cifs_tcp_ses_needs_reconnect(server, 1))
return 0;
cifs_mark_tcp_ses_conns_for_reconnect(server);
cifs: don't allow cifs_reconnect to exit with NULL socket pointer It's possible for the following set of events to happen: cifsd calls cifs_reconnect which reconnects the socket. A userspace process then calls cifs_negotiate_protocol to handle the NEGOTIATE and gets a reply. But, while processing the reply, cifsd calls cifs_reconnect again. Eventually the GlobalMid_Lock is dropped and the reply from the earlier NEGOTIATE completes and the tcpStatus is set to CifsGood. cifs_reconnect then goes through and closes the socket and sets the pointer to zero, but because the status is now CifsGood, the new socket is not created and cifs_reconnect exits with the socket pointer set to NULL. Fix this by only setting the tcpStatus to CifsGood if the tcpStatus is CifsNeedNegotiate, and by making sure that generic_ip_connect is always called at least once in cifs_reconnect. Note that this is not a perfect fix for this issue. It's still possible that the NEGOTIATE reply is handled after the socket has been closed and reconnected. In that case, the socket state will look correct but it no NEGOTIATE was performed on it be for the wrong socket. In that situation though the server should just shut down the socket on the next attempted send, rather than causing the oops that occurs today. Cc: <stable@kernel.org> # .38.x: fd88ce9: [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood Reported-and-Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-11 04:14:57 +08:00
do {
try_to_freeze();
cifs: ensure that srv_mutex is held when dealing with ssocket pointer Oleksii reported that he had seen an oops similar to this: BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 IP: [<ffffffff814dcc13>] sock_sendmsg+0x93/0xd0 PGD 0 Oops: 0000 [#1] PREEMPT SMP Modules linked in: ipt_MASQUERADE xt_REDIRECT xt_tcpudp iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack ip_tables x_tables carl9170 ath usb_storage f2fs nfnetlink_log nfnetlink md4 cifs dns_resolver hid_generic usbhid hid af_packet uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core videodev rfcomm btusb bnep bluetooth qmi_wwan qcserial cdc_wdm usb_wwan usbnet usbserial mii snd_hda_codec_hdmi snd_hda_codec_realtek iwldvm mac80211 coretemp intel_powerclamp kvm_intel kvm iwlwifi snd_hda_intel cfg80211 snd_hda_codec xhci_hcd e1000e ehci_pci snd_hwdep sdhci_pci snd_pcm ehci_hcd microcode psmouse sdhci thinkpad_acpi mmc_core i2c_i801 pcspkr usbcore hwmon snd_timer snd_page_alloc snd ptp rfkill pps_core soundcore evdev usb_common vboxnetflt(O) vboxdrv(O)Oops#2 Part8 loop tun binfmt_misc fuse msr acpi_call(O) ipv6 autofs4 CPU: 0 PID: 21612 Comm: kworker/0:1 Tainted: G W O 3.10.1SIGN #28 Hardware name: LENOVO 2306CTO/2306CTO, BIOS G2ET92WW (2.52 ) 02/22/2013 Workqueue: cifsiod cifs_echo_request [cifs] task: ffff8801e1f416f0 ti: ffff880148744000 task.ti: ffff880148744000 RIP: 0010:[<ffffffff814dcc13>] [<ffffffff814dcc13>] sock_sendmsg+0x93/0xd0 RSP: 0000:ffff880148745b00 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880148745b78 RCX: 0000000000000048 RDX: ffff880148745c90 RSI: ffff880181864a00 RDI: ffff880148745b78 RBP: ffff880148745c48 R08: 0000000000000048 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff880181864a00 R13: ffff880148745c90 R14: 0000000000000048 R15: 0000000000000048 FS: 0000000000000000(0000) GS:ffff88021e200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000088 CR3: 000000020c42c000 CR4: 00000000001407b0 Oops#2 Part7 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff880148745b30 ffffffff810c4af9 0000004848745b30 ffff880181864a00 ffffffff81ffbc40 0000000000000000 ffff880148745c90 ffffffff810a5aab ffff880148745bc0 ffffffff81ffbc40 ffff880148745b60 ffffffff815a9fb8 Call Trace: [<ffffffff810c4af9>] ? finish_task_switch+0x49/0xe0 [<ffffffff810a5aab>] ? lock_timer_base.isra.36+0x2b/0x50 [<ffffffff815a9fb8>] ? _raw_spin_unlock_irqrestore+0x18/0x40 [<ffffffff810a673f>] ? try_to_del_timer_sync+0x4f/0x70 [<ffffffff815aa38f>] ? _raw_spin_unlock_bh+0x1f/0x30 [<ffffffff814dcc87>] kernel_sendmsg+0x37/0x50 [<ffffffffa081a0e0>] smb_send_kvec+0xd0/0x1d0 [cifs] [<ffffffffa081a263>] smb_send_rqst+0x83/0x1f0 [cifs] [<ffffffffa081ab6c>] cifs_call_async+0xec/0x1b0 [cifs] [<ffffffffa08245e0>] ? free_rsp_buf+0x40/0x40 [cifs] Oops#2 Part6 [<ffffffffa082606e>] SMB2_echo+0x8e/0xb0 [cifs] [<ffffffffa0808789>] cifs_echo_request+0x79/0xa0 [cifs] [<ffffffff810b45b3>] process_one_work+0x173/0x4a0 [<ffffffff810b52a1>] worker_thread+0x121/0x3a0 [<ffffffff810b5180>] ? manage_workers.isra.27+0x2b0/0x2b0 [<ffffffff810bae00>] kthread+0xc0/0xd0 [<ffffffff810bad40>] ? kthread_create_on_node+0x120/0x120 [<ffffffff815b199c>] ret_from_fork+0x7c/0xb0 [<ffffffff810bad40>] ? kthread_create_on_node+0x120/0x120 Code: 84 24 b8 00 00 00 4c 89 f1 4c 89 ea 4c 89 e6 48 89 df 4c 89 60 18 48 c7 40 28 00 00 00 00 4c 89 68 30 44 89 70 14 49 8b 44 24 28 <ff> 90 88 00 00 00 3d ef fd ff ff 74 10 48 8d 65 e0 5b 41 5c 41 RIP [<ffffffff814dcc13>] sock_sendmsg+0x93/0xd0 RSP <ffff880148745b00> CR2: 0000000000000088 The client was in the middle of trying to send a frame when the server->ssocket pointer got zeroed out. In most places, that we access that pointer, the srv_mutex is held. There's only one spot that I see that the server->ssocket pointer gets set and the srv_mutex isn't held. This patch corrects that. The upstream bug report was here: https://bugzilla.kernel.org/show_bug.cgi?id=60557 Cc: <stable@vger.kernel.org> Reported-by: Oleksii Shevchuk <alxchk@gmail.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
2013-09-05 20:38:10 +08:00
mutex_lock(&server->srv_mutex);
if (!cifs_swn_set_server_dstaddr(server)) {
/* resolve the hostname again to make sure that IP address is up-to-date */
rc = reconn_set_ipaddr_from_hostname(server);
cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
}
cifs: set up next DFS target before generic_ip_connect() If we mount a very specific DFS link \\FS0.FOO.COM\dfs\link -> \FS0\share1, \FS1\share2 where its target list contains NB names ("FS0" & "FS1") rather than FQDN ones ("FS0.FOO.COM" & "FS1.FOO.COM"), we end up connecting to \FOO\share1 but server->hostname will have "FOO.COM". The reason is because both "FS0" and "FS0.FOO.COM" resolve to same IP address and they share same TCP server connection, but "FS0.FOO.COM" was the first hostname set -- which is OK. However, if the echo thread timeouts and we still have a good connection to "FS0", in cifs_reconnect() rc = generic_ip_connect(server) -> success if (rc) { ... reconn_inval_dfs_target(server, cifs_sb, &tgt_list, &tgt_it); ... } ... it successfully reconnects to "FS0" server but does not set up next DFS target - which should be the same target server "\FS0\share1" - and server->hostname remains set to "FS0.FOO.COM" rather than "FS0", as reconn_inval_dfs_target() would have it set to "FS0" if called earlier. Finally, in __smb2_reconnect(), the reconnect of tcons would fail because tcon->ses->server->hostname (FS0.FOO.COM) does not match DFS target's hostname (FS0). Fix that by calling reconn_inval_dfs_target() before generic_ip_connect() so server->hostname will get updated correctly prior to reconnecting its tcons in __smb2_reconnect(). With "cifs: handle hostnames that resolve to same ip in failover" patch - The above problem would not occur. - We could save an DNS query to find out that they both resolve to the same ip address. Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-05-20 02:38:27 +08:00
if (cifs_rdma_enabled(server))
rc = smbd_reconnect(server);
else
rc = generic_ip_connect(server);
if (rc) {
mutex_unlock(&server->srv_mutex);
cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
msleep(3000);
} else {
atomic_inc(&tcpSesReconnectCount);
set_credits(server, 1);
spin_lock(&GlobalMid_Lock);
if (server->tcpStatus != CifsExiting)
server->tcpStatus = CifsNeedNegotiate;
spin_unlock(&GlobalMid_Lock);
cifs_swn_reset_server_dstaddr(server);
mutex_unlock(&server->srv_mutex);
}
cifs: don't allow cifs_reconnect to exit with NULL socket pointer It's possible for the following set of events to happen: cifsd calls cifs_reconnect which reconnects the socket. A userspace process then calls cifs_negotiate_protocol to handle the NEGOTIATE and gets a reply. But, while processing the reply, cifsd calls cifs_reconnect again. Eventually the GlobalMid_Lock is dropped and the reply from the earlier NEGOTIATE completes and the tcpStatus is set to CifsGood. cifs_reconnect then goes through and closes the socket and sets the pointer to zero, but because the status is now CifsGood, the new socket is not created and cifs_reconnect exits with the socket pointer set to NULL. Fix this by only setting the tcpStatus to CifsGood if the tcpStatus is CifsNeedNegotiate, and by making sure that generic_ip_connect is always called at least once in cifs_reconnect. Note that this is not a perfect fix for this issue. It's still possible that the NEGOTIATE reply is handled after the socket has been closed and reconnected. In that case, the socket state will look correct but it no NEGOTIATE was performed on it be for the wrong socket. In that situation though the server should just shut down the socket on the next attempted send, rather than causing the oops that occurs today. Cc: <stable@kernel.org> # .38.x: fd88ce9: [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood Reported-and-Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-11 04:14:57 +08:00
} while (server->tcpStatus == CifsNeedReconnect);
if (server->tcpStatus == CifsNeedNegotiate)
mod_delayed_work(cifsiod_wq, &server->echo, 0);
wake_up(&server->response_q);
return rc;
}
#ifdef CONFIG_CIFS_DFS_UPCALL
static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
{
int rc;
char *hostname;
if (!cifs_swn_set_server_dstaddr(server)) {
if (server->hostname != target) {
hostname = extract_hostname(target);
if (!IS_ERR(hostname)) {
kfree(server->hostname);
server->hostname = hostname;
} else {
cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
__func__, PTR_ERR(hostname));
cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
server->hostname);
}
}
/* resolve the hostname again to make sure that IP address is up-to-date. */
rc = reconn_set_ipaddr_from_hostname(server);
cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
}
/* Reconnect the socket */
if (cifs_rdma_enabled(server))
rc = smbd_reconnect(server);
else
rc = generic_ip_connect(server);
return rc;
}
static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
struct dfs_cache_tgt_iterator **target_hint)
{
int rc;
struct dfs_cache_tgt_iterator *tit;
*target_hint = NULL;
/* If dfs target list is empty, then reconnect to last server */
tit = dfs_cache_get_tgt_iterator(tl);
if (!tit)
return __reconnect_target_unlocked(server, server->hostname);
/* Otherwise, try every dfs target in @tl */
for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
if (!rc) {
*target_hint = tit;
break;
}
}
return rc;
}
static int reconnect_dfs_server(struct TCP_Server_Info *server)
{
int rc = 0;
const char *refpath = server->current_fullpath + 1;
struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
struct dfs_cache_tgt_iterator *target_hint = NULL;
int num_targets = 0;
/*
* Determine the number of dfs targets the referral path in @cifs_sb resolves to.
*
* smb2_reconnect() needs to know how long it should wait based upon the number of dfs
* targets (server->nr_targets). It's also possible that the cached referral was cleared
* through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
* refreshing the referral, so, in this case, default it to 1.
*/
if (!dfs_cache_noreq_find(refpath, NULL, &tl))
num_targets = dfs_cache_get_nr_tgts(&tl);
if (!num_targets)
num_targets = 1;
if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
return 0;
cifs_mark_tcp_ses_conns_for_reconnect(server);
do {
try_to_freeze();
mutex_lock(&server->srv_mutex);
rc = reconnect_target_unlocked(server, &tl, &target_hint);
if (rc) {
/* Failed to reconnect socket */
mutex_unlock(&server->srv_mutex);
cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
msleep(3000);
continue;
}
/*
* Socket was created. Update tcp session status to CifsNeedNegotiate so that a
* process waiting for reconnect will know it needs to re-establish session and tcon
* through the reconnected target server.
*/
atomic_inc(&tcpSesReconnectCount);
set_credits(server, 1);
spin_lock(&GlobalMid_Lock);
if (server->tcpStatus != CifsExiting)
server->tcpStatus = CifsNeedNegotiate;
spin_unlock(&GlobalMid_Lock);
cifs_swn_reset_server_dstaddr(server);
mutex_unlock(&server->srv_mutex);
} while (server->tcpStatus == CifsNeedReconnect);
if (target_hint)
dfs_cache_noreq_update_tgthint(refpath, target_hint);
dfs_cache_free_tgts(&tl);
/* Need to set up echo worker again once connection has been established */
if (server->tcpStatus == CifsNeedNegotiate)
mod_delayed_work(cifsiod_wq, &server->echo, 0);
wake_up(&server->response_q);
return rc;
}
int cifs_reconnect(struct TCP_Server_Info *server)
{
/* If tcp session is not an dfs connection, then reconnect to last target server */
spin_lock(&cifs_tcp_ses_lock);
if (!server->is_dfs_conn || !server->origin_fullpath || !server->leaf_fullpath) {
spin_unlock(&cifs_tcp_ses_lock);
return __cifs_reconnect(server);
}
spin_unlock(&cifs_tcp_ses_lock);
return reconnect_dfs_server(server);
}
#else
int cifs_reconnect(struct TCP_Server_Info *server)
{
return __cifs_reconnect(server);
}
#endif
static void
cifs_echo_request(struct work_struct *work)
{
int rc;
struct TCP_Server_Info *server = container_of(work,
struct TCP_Server_Info, echo.work);
/*
* We cannot send an echo if it is disabled.
* Also, no need to ping if we got a response recently.
*/
if (server->tcpStatus == CifsNeedReconnect ||
server->tcpStatus == CifsExiting ||
server->tcpStatus == CifsNew ||
(server->ops->can_echo && !server->ops->can_echo(server)) ||
time_before(jiffies, server->lstrp + server->echo_interval - HZ))
goto requeue_echo;
rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
if (rc)
cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
server->hostname);
/* Check witness registrations */
cifs_swn_check();
requeue_echo:
queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
}
static bool
allocate_buffers(struct TCP_Server_Info *server)
{
if (!server->bigbuf) {
server->bigbuf = (char *)cifs_buf_get();
if (!server->bigbuf) {
cifs_server_dbg(VFS, "No memory for large SMB response\n");
msleep(3000);
/* retry will check if exiting */
return false;
}
} else if (server->large_buf) {
/* we are reusing a dirty large buf, clear its start */
memset(server->bigbuf, 0, HEADER_SIZE(server));
}
if (!server->smallbuf) {
server->smallbuf = (char *)cifs_small_buf_get();
if (!server->smallbuf) {
cifs_server_dbg(VFS, "No memory for SMB response\n");
msleep(1000);
/* retry will check if exiting */
return false;
}
/* beginning of smb buffer is cleared in our buf_get */
} else {
/* if existing small buf clear beginning */
memset(server->smallbuf, 0, HEADER_SIZE(server));
}
return true;
}
static bool
server_unresponsive(struct TCP_Server_Info *server)
{
/*
* We need to wait 3 echo intervals to make sure we handle such
* situations right:
* 1s client sends a normal SMB request
* 2s client gets a response
* 30s echo workqueue job pops, and decides we got a response recently
* and don't need to send another
* ...
* 65s kernel_recvmsg times out, and we see that we haven't gotten
* a response in >60s.
*/
cifs: Check for timeout on Negotiate stage Some servers seem to accept connections while booting but never send the SMBNegotiate response neither close the connection, causing all processes accessing the share hang on uninterruptible sleep state. This happens when the cifs_demultiplex_thread detects the server is unresponsive so releases the socket and start trying to reconnect. At some point, the faulty server will accept the socket and the TCP status will be set to NeedNegotiate. The first issued command accessing the share will start the negotiation (pid 5828 below), but the response will never arrive so other commands will be blocked waiting on the mutex (pid 55352). This patch checks for unresponsive servers also on the negotiate stage releasing the socket and reconnecting if the response is not received and checking again the tcp state when the mutex is acquired. PID: 55352 TASK: ffff880fd6cc02c0 CPU: 0 COMMAND: "ls" #0 [ffff880fd9add9f0] schedule at ffffffff81467eb9 #1 [ffff880fd9addb38] __mutex_lock_slowpath at ffffffff81468fe0 #2 [ffff880fd9addba8] mutex_lock at ffffffff81468b1a #3 [ffff880fd9addbc0] cifs_reconnect_tcon at ffffffffa042f905 [cifs] #4 [ffff880fd9addc60] smb_init at ffffffffa042faeb [cifs] #5 [ffff880fd9addca0] CIFSSMBQPathInfo at ffffffffa04360b5 [cifs] .... Which is waiting a mutex owned by: PID: 5828 TASK: ffff880fcc55e400 CPU: 0 COMMAND: "xxxx" #0 [ffff880fbfdc19b8] schedule at ffffffff81467eb9 #1 [ffff880fbfdc1b00] wait_for_response at ffffffffa044f96d [cifs] #2 [ffff880fbfdc1b60] SendReceive at ffffffffa04505ce [cifs] #3 [ffff880fbfdc1bb0] CIFSSMBNegotiate at ffffffffa0438d79 [cifs] #4 [ffff880fbfdc1c50] cifs_negotiate_protocol at ffffffffa043b383 [cifs] #5 [ffff880fbfdc1c80] cifs_reconnect_tcon at ffffffffa042f911 [cifs] #6 [ffff880fbfdc1d20] smb_init at ffffffffa042faeb [cifs] #7 [ffff880fbfdc1d60] CIFSSMBQFSInfo at ffffffffa0434eb0 [cifs] .... Signed-off-by: Samuel Cabrero <scabrero@suse.de> Reviewed-by: Aurélien Aptel <aaptel@suse.de> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
2017-07-11 18:44:39 +08:00
if ((server->tcpStatus == CifsGood ||
server->tcpStatus == CifsNeedNegotiate) &&
(!server->ops->can_echo || server->ops->can_echo(server)) &&
time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
(3 * server->echo_interval) / HZ);
cifs_reconnect(server);
return true;
}
return false;
}
static inline bool
zero_credits(struct TCP_Server_Info *server)
{
int val;
spin_lock(&server->req_lock);
val = server->credits + server->echo_credits + server->oplock_credits;
if (server->in_flight == 0 && val == 0) {
spin_unlock(&server->req_lock);
return true;
}
spin_unlock(&server->req_lock);
return false;
}
static int
cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
{
int length = 0;
int total_read;
smb_msg->msg_control = NULL;
smb_msg->msg_controllen = 0;
for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
try_to_freeze();
/* reconnect if no credits and no requests in flight */
if (zero_credits(server)) {
cifs_reconnect(server);
return -ECONNABORTED;
}
if (server_unresponsive(server))
return -ECONNABORTED;
if (cifs_rdma_enabled(server) && server->smbd_conn)
length = smbd_recv(server->smbd_conn, smb_msg);
else
length = sock_recvmsg(server->ssocket, smb_msg, 0);
if (server->tcpStatus == CifsExiting)
return -ESHUTDOWN;
if (server->tcpStatus == CifsNeedReconnect) {
cifs_reconnect(server);
return -ECONNABORTED;
}
if (length == -ERESTARTSYS ||
length == -EAGAIN ||
length == -EINTR) {
/*
* Minimum sleep to prevent looping, allowing socket
* to clear and app threads to set tcpStatus
* CifsNeedReconnect if server hung.
*/
usleep_range(1000, 2000);
length = 0;
continue;
}
if (length <= 0) {
cifs_dbg(FYI, "Received no data or error: %d\n", length);
cifs_reconnect(server);
return -ECONNABORTED;
}
}
return total_read;
}
int
cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
unsigned int to_read)
{
struct msghdr smb_msg;
struct kvec iov = {.iov_base = buf, .iov_len = to_read};
iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
return cifs_readv_from_socket(server, &smb_msg);
}
ssize_t
cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
{
struct msghdr smb_msg;
/*
* iov_iter_discard already sets smb_msg.type and count and iov_offset
* and cifs_readv_from_socket sets msg_control and msg_controllen
* so little to initialize in struct msghdr
*/
smb_msg.msg_name = NULL;
smb_msg.msg_namelen = 0;
iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
return cifs_readv_from_socket(server, &smb_msg);
}
int
cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
unsigned int page_offset, unsigned int to_read)
{
struct msghdr smb_msg;
struct bio_vec bv = {
.bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
return cifs_readv_from_socket(server, &smb_msg);
}
static bool
is_smb_response(struct TCP_Server_Info *server, unsigned char type)
{
/*
* The first byte big endian of the length field,
* is actually not part of the length but the type
* with the most common, zero, as regular data.
*/
switch (type) {
case RFC1002_SESSION_MESSAGE:
/* Regular SMB response */
return true;
case RFC1002_SESSION_KEEP_ALIVE:
cifs_dbg(FYI, "RFC 1002 session keep alive\n");
break;
case RFC1002_POSITIVE_SESSION_RESPONSE:
cifs_dbg(FYI, "RFC 1002 positive session response\n");
break;
case RFC1002_NEGATIVE_SESSION_RESPONSE:
/*
* We get this from Windows 98 instead of an error on
* SMB negprot response.
*/
cifs_dbg(FYI, "RFC 1002 negative session response\n");
/* give server a second to clean up */
msleep(1000);
/*
* Always try 445 first on reconnect since we get NACK
* on some if we ever connected to port 139 (the NACK
* is since we do not begin with RFC1001 session
* initialize frame).
*/
cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
cifs_reconnect(server);
break;
default:
cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
cifs_reconnect(server);
}
return false;
}
void
dequeue_mid(struct mid_q_entry *mid, bool malformed)
{
#ifdef CONFIG_CIFS_STATS2
mid->when_received = jiffies;
#endif
spin_lock(&GlobalMid_Lock);
if (!malformed)
mid->mid_state = MID_RESPONSE_RECEIVED;
else
mid->mid_state = MID_RESPONSE_MALFORMED;
/*
* Trying to handle/dequeue a mid after the send_recv()
* function has finished processing it is a bug.
*/
if (mid->mid_flags & MID_DELETED) {
spin_unlock(&GlobalMid_Lock);
pr_warn_once("trying to dequeue a deleted mid\n");
} else {
list_del_init(&mid->qhead);
CIFS: Fix retry mid list corruption on reconnects When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-22 23:41:42 +08:00
mid->mid_flags |= MID_DELETED;
spin_unlock(&GlobalMid_Lock);
CIFS: Fix retry mid list corruption on reconnects When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-22 23:41:42 +08:00
}
}
static unsigned int
smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
{
struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
/*
* SMB1 does not use credits.
*/
if (server->vals->header_preamble_size)
return 0;
return le16_to_cpu(shdr->CreditRequest);
}
static void
handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
char *buf, int malformed)
{
if (server->ops->check_trans2 &&
server->ops->check_trans2(mid, server, buf, malformed))
return;
mid->credits_received = smb2_get_credits_from_hdr(buf, server);
mid->resp_buf = buf;
mid->large_buf = server->large_buf;
/* Was previous buf put in mpx struct for multi-rsp? */
if (!mid->multiRsp) {
/* smb buffer will be freed by user thread */
if (server->large_buf)
server->bigbuf = NULL;
else
server->smallbuf = NULL;
}
dequeue_mid(mid, malformed);
}
static void clean_demultiplex_info(struct TCP_Server_Info *server)
{
int length;
/* take it off the list, if it's not already */
spin_lock(&cifs_tcp_ses_lock);
list_del_init(&server->tcp_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
cancel_delayed_work_sync(&server->echo);
cancel_delayed_work_sync(&server->resolve);
spin_lock(&GlobalMid_Lock);
server->tcpStatus = CifsExiting;
spin_unlock(&GlobalMid_Lock);
wake_up_all(&server->response_q);
/* check if we have blocked requests that need to free */
spin_lock(&server->req_lock);
if (server->credits <= 0)
server->credits = 1;
spin_unlock(&server->req_lock);
/*
* Although there should not be any requests blocked on this queue it
* can not hurt to be paranoid and try to wake up requests that may
* haven been blocked when more than 50 at time were on the wire to the
* same server - they now will see the session is in exit state and get
* out of SendReceive.
*/
wake_up_all(&server->request_q);
/* give those requests time to exit */
msleep(125);
if (cifs_rdma_enabled(server))
smbd_destroy(server);
if (server->ssocket) {
sock_release(server->ssocket);
server->ssocket = NULL;
}
if (!list_empty(&server->pending_mid_q)) {
struct list_head dispose_list;
struct mid_q_entry *mid_entry;
struct list_head *tmp, *tmp2;
INIT_LIST_HEAD(&dispose_list);
spin_lock(&GlobalMid_Lock);
list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
CIFS: Fix retry mid list corruption on reconnects When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-22 23:41:42 +08:00
kref_get(&mid_entry->refcount);
mid_entry->mid_state = MID_SHUTDOWN;
list_move(&mid_entry->qhead, &dispose_list);
CIFS: Fix retry mid list corruption on reconnects When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-22 23:41:42 +08:00
mid_entry->mid_flags |= MID_DELETED;
}
spin_unlock(&GlobalMid_Lock);
/* now walk dispose list and issue callbacks */
list_for_each_safe(tmp, tmp2, &dispose_list) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
list_del_init(&mid_entry->qhead);
mid_entry->callback(mid_entry);
CIFS: Fix retry mid list corruption on reconnects When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-10-22 23:41:42 +08:00
cifs_mid_q_entry_release(mid_entry);
}
/* 1/8th of sec is more than enough time for them to exit */
msleep(125);
}
if (!list_empty(&server->pending_mid_q)) {
/*
* mpx threads have not exited yet give them at least the smb
* send timeout time for long ops.
*
* Due to delays on oplock break requests, we need to wait at
* least 45 seconds before giving up on a request getting a
* response and going ahead and killing cifsd.
*/
cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
msleep(46000);
/*
* If threads still have not exited they are probably never
* coming home not much else we can do but free the memory.
*/
}
#ifdef CONFIG_CIFS_DFS_UPCALL
kfree(server->origin_fullpath);
kfree(server->leaf_fullpath);
#endif
kfree(server);
length = atomic_dec_return(&tcpSesAllocCount);
if (length > 0)
mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
}
static int
standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
{
int length;
char *buf = server->smallbuf;
unsigned int pdu_length = server->pdu_size;
/* make sure this will fit in a large buffer */
if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
server->vals->header_preamble_size) {
cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
cifs_reconnect(server);
return -ECONNABORTED;
}
/* switch to large buffer if too big for a small one */
if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
server->large_buf = true;
memcpy(server->bigbuf, buf, server->total_read);
buf = server->bigbuf;
}
/* now read the rest */
length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
pdu_length - HEADER_SIZE(server) + 1
+ server->vals->header_preamble_size);
if (length < 0)
return length;
server->total_read += length;
dump_smb(buf, server->total_read);
return cifs_handle_standard(server, mid);
}
int
cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
{
char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
int length;
/*
* We know that we received enough to get to the MID as we
* checked the pdu_length earlier. Now check to see
* if the rest of the header is OK. We borrow the length
* var for the rest of the loop to avoid a new stack var.
*
* 48 bytes is enough to display the header and a little bit
* into the payload for debugging purposes.
*/
length = server->ops->check_message(buf, server->total_read, server);
if (length != 0)
cifs_dump_mem("Bad SMB: ", buf,
min_t(unsigned int, server->total_read, 48));
if (server->ops->is_session_expired &&
server->ops->is_session_expired(buf)) {
cifs_reconnect(server);
return -1;
}
if (server->ops->is_status_pending &&
server->ops->is_status_pending(buf, server))
return -1;
if (!mid)
return length;
handle_mid(mid, server, buf, length);
return 0;
}
static void
smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
{
struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
int scredits, in_flight;
/*
* SMB1 does not use credits.
*/
if (server->vals->header_preamble_size)
return;
if (shdr->CreditRequest) {
spin_lock(&server->req_lock);
server->credits += le16_to_cpu(shdr->CreditRequest);
scredits = server->credits;
in_flight = server->in_flight;
spin_unlock(&server->req_lock);
wake_up(&server->request_q);
trace_smb3_add_credits(server->CurrentMid,
server->conn_id, server->hostname, scredits,
le16_to_cpu(shdr->CreditRequest), in_flight);
cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
__func__, le16_to_cpu(shdr->CreditRequest),
scredits);
}
}
static int
cifs_demultiplex_thread(void *p)
{
int i, num_mids, length;
struct TCP_Server_Info *server = p;
unsigned int pdu_length;
unsigned int next_offset;
char *buf = NULL;
struct task_struct *task_to_wake = NULL;
struct mid_q_entry *mids[MAX_COMPOUND];
char *bufs[MAX_COMPOUND];
unsigned int noreclaim_flag, num_io_timeout = 0;
noreclaim_flag = memalloc_noreclaim_save();
cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
length = atomic_inc_return(&tcpSesAllocCount);
if (length > 1)
mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
set_freezable();
signal: Allow cifs and drbd to receive their terminating signals My recent to change to only use force_sig for a synchronous events wound up breaking signal reception cifs and drbd. I had overlooked the fact that by default kthreads start out with all signals set to SIG_IGN. So a change I thought was safe turned out to have made it impossible for those kernel thread to catch their signals. Reverting the work on force_sig is a bad idea because what the code was doing was very much a misuse of force_sig. As the way force_sig ultimately allowed the signal to happen was to change the signal handler to SIG_DFL. Which after the first signal will allow userspace to send signals to these kernel threads. At least for wake_ack_receiver in drbd that does not appear actively wrong. So correct this problem by adding allow_kernel_signal that will allow signals whose siginfo reports they were sent by the kernel through, but will not allow userspace generated signals, and update cifs and drbd to call allow_kernel_signal in an appropriate place so that their thread can receive this signal. Fixing things this way ensures that userspace won't be able to send signals and cause problems, that it is clear which signals the threads are expecting to receive, and it guarantees that nothing else in the system will be affected. This change was partly inspired by similar cifs and drbd patches that added allow_signal. Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com> Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Cc: Steve French <smfrench@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: David Laight <David.Laight@ACULAB.COM> Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes") Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig") Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig") Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-08-17 01:33:54 +08:00
allow_kernel_signal(SIGKILL);
while (server->tcpStatus != CifsExiting) {
if (try_to_freeze())
continue;
if (!allocate_buffers(server))
continue;
server->large_buf = false;
buf = server->smallbuf;
pdu_length = 4; /* enough to get RFC1001 header */
length = cifs_read_from_socket(server, buf, pdu_length);
if (length < 0)
continue;
if (server->vals->header_preamble_size == 0)
server->total_read = 0;
else
server->total_read = length;
/*
* The right amount was read from socket - 4 bytes,
* so we can now interpret the length field.
*/
pdu_length = get_rfc1002_length(buf);
cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
if (!is_smb_response(server, buf[0]))
continue;
next_pdu:
server->pdu_size = pdu_length;
/* make sure we have enough to get to the MID */
if (server->pdu_size < HEADER_SIZE(server) - 1 -
server->vals->header_preamble_size) {
cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
server->pdu_size);
cifs_reconnect(server);
continue;
}
/* read down to the MID */
length = cifs_read_from_socket(server,
buf + server->vals->header_preamble_size,
HEADER_SIZE(server) - 1
- server->vals->header_preamble_size);
if (length < 0)
continue;
server->total_read += length;
if (server->ops->next_header) {
next_offset = server->ops->next_header(buf);
if (next_offset)
server->pdu_size = next_offset;
}
memset(mids, 0, sizeof(mids));
memset(bufs, 0, sizeof(bufs));
num_mids = 0;
if (server->ops->is_transform_hdr &&
server->ops->receive_transform &&
server->ops->is_transform_hdr(buf)) {
length = server->ops->receive_transform(server,
mids,
bufs,
&num_mids);
} else {
mids[0] = server->ops->find_mid(server, buf);
bufs[0] = buf;
num_mids = 1;
if (!mids[0] || !mids[0]->receive)
length = standard_receive3(server, mids[0]);
else
length = mids[0]->receive(server, mids[0]);
}
cifs: Fix use after free of a mid_q_entry With protocol version 2.0 mounts we have seen crashes with corrupt mid entries. Either the server->pending_mid_q list becomes corrupt with a cyclic reference in one element or a mid object fetched by the demultiplexer thread becomes overwritten during use. Code review identified a race between the demultiplexer thread and the request issuing thread. The demultiplexer thread seems to be written with the assumption that it is the sole user of the mid object until it calls the mid callback which either wakes the issuer task or deletes the mid. This assumption is not true because the issuer task can be woken up earlier by a signal. If the demultiplexer thread has proceeded as far as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer thread will happily end up calling cifs_delete_mid while the demultiplexer thread still is using the mid object. Inserting a delay in the cifs demultiplexer thread widens the race window and makes reproduction of the race very easy: if (server->large_buf) buf = server->bigbuf; + usleep_range(500, 4000); server->lstrp = jiffies; To resolve this I think the proper solution involves putting a reference count on the mid object. This patch makes sure that the demultiplexer thread holds a reference until it has finished processing the transaction. Cc: stable@vger.kernel.org Signed-off-by: Lars Persson <larper@axis.com> Acked-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-25 20:05:25 +08:00
if (length < 0) {
for (i = 0; i < num_mids; i++)
if (mids[i])
cifs_mid_q_entry_release(mids[i]);
continue;
cifs: Fix use after free of a mid_q_entry With protocol version 2.0 mounts we have seen crashes with corrupt mid entries. Either the server->pending_mid_q list becomes corrupt with a cyclic reference in one element or a mid object fetched by the demultiplexer thread becomes overwritten during use. Code review identified a race between the demultiplexer thread and the request issuing thread. The demultiplexer thread seems to be written with the assumption that it is the sole user of the mid object until it calls the mid callback which either wakes the issuer task or deletes the mid. This assumption is not true because the issuer task can be woken up earlier by a signal. If the demultiplexer thread has proceeded as far as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer thread will happily end up calling cifs_delete_mid while the demultiplexer thread still is using the mid object. Inserting a delay in the cifs demultiplexer thread widens the race window and makes reproduction of the race very easy: if (server->large_buf) buf = server->bigbuf; + usleep_range(500, 4000); server->lstrp = jiffies; To resolve this I think the proper solution involves putting a reference count on the mid object. This patch makes sure that the demultiplexer thread holds a reference until it has finished processing the transaction. Cc: stable@vger.kernel.org Signed-off-by: Lars Persson <larper@axis.com> Acked-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-25 20:05:25 +08:00
}
if (server->ops->is_status_io_timeout &&
server->ops->is_status_io_timeout(buf)) {
num_io_timeout++;
if (num_io_timeout > NUM_STATUS_IO_TIMEOUT) {
cifs_reconnect(server);
num_io_timeout = 0;
continue;
}
}
server->lstrp = jiffies;
for (i = 0; i < num_mids; i++) {
if (mids[i] != NULL) {
mids[i]->resp_buf_size = server->pdu_size;
cifs: Fix use after free of a mid_q_entry With protocol version 2.0 mounts we have seen crashes with corrupt mid entries. Either the server->pending_mid_q list becomes corrupt with a cyclic reference in one element or a mid object fetched by the demultiplexer thread becomes overwritten during use. Code review identified a race between the demultiplexer thread and the request issuing thread. The demultiplexer thread seems to be written with the assumption that it is the sole user of the mid object until it calls the mid callback which either wakes the issuer task or deletes the mid. This assumption is not true because the issuer task can be woken up earlier by a signal. If the demultiplexer thread has proceeded as far as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer thread will happily end up calling cifs_delete_mid while the demultiplexer thread still is using the mid object. Inserting a delay in the cifs demultiplexer thread widens the race window and makes reproduction of the race very easy: if (server->large_buf) buf = server->bigbuf; + usleep_range(500, 4000); server->lstrp = jiffies; To resolve this I think the proper solution involves putting a reference count on the mid object. This patch makes sure that the demultiplexer thread holds a reference until it has finished processing the transaction. Cc: stable@vger.kernel.org Signed-off-by: Lars Persson <larper@axis.com> Acked-by: Paulo Alcantara <palcantara@suse.de> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-25 20:05:25 +08:00
if (bufs[i] && server->ops->is_network_name_deleted)
server->ops->is_network_name_deleted(bufs[i],
server);
if (!mids[i]->multiRsp || mids[i]->multiEnd)
mids[i]->callback(mids[i]);
cifs_mid_q_entry_release(mids[i]);
} else if (server->ops->is_oplock_break &&
server->ops->is_oplock_break(bufs[i],
server)) {
smb2_add_credits_from_hdr(bufs[i], server);
cifs_dbg(FYI, "Received oplock break\n");
} else {
cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
atomic_read(&midCount));
cifs_dump_mem("Received Data is: ", bufs[i],
HEADER_SIZE(server));
smb2_add_credits_from_hdr(bufs[i], server);
#ifdef CONFIG_CIFS_DEBUG2
if (server->ops->dump_detail)
server->ops->dump_detail(bufs[i],
server);
cifs_dump_mids(server);
#endif /* CIFS_DEBUG2 */
}
}
if (pdu_length > server->pdu_size) {
if (!allocate_buffers(server))
continue;
pdu_length -= server->pdu_size;
server->total_read = 0;
server->large_buf = false;
buf = server->smallbuf;
goto next_pdu;
}
} /* end while !EXITING */
/* buffer usually freed in free_mid - need to free it here on exit */
cifs_buf_release(server->bigbuf);
if (server->smallbuf) /* no sense logging a debug message if NULL */
cifs_small_buf_release(server->smallbuf);
task_to_wake = xchg(&server->tsk, NULL);
clean_demultiplex_info(server);
/* if server->tsk was NULL then wait for a signal before exiting */
if (!task_to_wake) {
set_current_state(TASK_INTERRUPTIBLE);
while (!signal_pending(current)) {
schedule();
set_current_state(TASK_INTERRUPTIBLE);
}
set_current_state(TASK_RUNNING);
}
memalloc_noreclaim_restore(noreclaim_flag);
module_put_and_exit(0);
}
/*
* Returns true if srcaddr isn't specified and rhs isn't specified, or
* if srcaddr is specified and matches the IP address of the rhs argument
*/
bool
cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
{
switch (srcaddr->sa_family) {
case AF_UNSPEC:
return (rhs->sa_family == AF_UNSPEC);
case AF_INET: {
struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
}
case AF_INET6: {
struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
}
default:
WARN_ON(1);
return false; /* don't expect to be here */
}
}
/*
* If no port is specified in addr structure, we try to match with 445 port
* and if it fails - with 139 ports. It should be called only if address
* families of server and addr are equal.
*/
static bool
match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
{
Elminate sparse __CHECK_ENDIAN__ warnings on port conversion Ports are __be16 not unsigned short int Eliminates the remaining fixable endian warnings: ~/cifs-2.6$ make modules C=1 M=fs/cifs CF=-D__CHECK_ENDIAN__ CHECK fs/cifs/connect.c fs/cifs/connect.c:2408:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2408:23: expected unsigned short *sport fs/cifs/connect.c:2408:23: got restricted __be16 *<noident> fs/cifs/connect.c:2410:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2410:23: expected unsigned short *sport fs/cifs/connect.c:2410:23: got restricted __be16 *<noident> fs/cifs/connect.c:2416:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2416:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2416:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2423:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2423:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2423:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2326:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2326:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2326:23: got restricted __be16 [usertype] sin6_port fs/cifs/connect.c:2330:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2330:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2330:23: got restricted __be16 [usertype] sin_port fs/cifs/connect.c:2394:22: warning: restricted __be16 degrades to integer Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-03-14 02:55:55 +08:00
__be16 port, *sport;
/* SMBDirect manages its own ports, don't match it here */
if (server->rdma)
return true;
switch (addr->sa_family) {
case AF_INET:
sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
port = ((struct sockaddr_in *) addr)->sin_port;
break;
case AF_INET6:
sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
port = ((struct sockaddr_in6 *) addr)->sin6_port;
break;
default:
WARN_ON(1);
return false;
}
if (!port) {
port = htons(CIFS_PORT);
if (port == *sport)
return true;
port = htons(RFC1001_PORT);
}
return port == *sport;
}
static bool
match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
struct sockaddr *srcaddr)
{
switch (addr->sa_family) {
case AF_INET: {
struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
struct sockaddr_in *srv_addr4 =
(struct sockaddr_in *)&server->dstaddr;
if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
return false;
break;
}
case AF_INET6: {
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
struct sockaddr_in6 *srv_addr6 =
(struct sockaddr_in6 *)&server->dstaddr;
if (!ipv6_addr_equal(&addr6->sin6_addr,
&srv_addr6->sin6_addr))
return false;
if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
return false;
break;
}
default:
WARN_ON(1);
return false; /* don't expect to be here */
}
if (!cifs_match_ipaddr(srcaddr, (struct sockaddr *)&server->srcaddr))
return false;
return true;
}
static bool
match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
/*
* The select_sectype function should either return the ctx->sectype
* that was specified, or "Unspecified" if that sectype was not
* compatible with the given NEGOTIATE request.
*/
if (server->ops->select_sectype(server, ctx->sectype)
== Unspecified)
return false;
/*
* Now check if signing mode is acceptable. No need to check
* global_secflags at this point since if MUST_SIGN is set then
* the server->sign had better be too.
*/
if (ctx->sign && !server->sign)
return false;
return true;
}
static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
if (ctx->nosharesock) {
server->nosharesock = true;
return 0;
}
/* this server does not share socket */
if (server->nosharesock)
return 0;
/* If multidialect negotiation see if existing sessions match one */
if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
if (server->vals->protocol_id < SMB30_PROT_ID)
return 0;
} else if (strcmp(ctx->vals->version_string,
SMBDEFAULT_VERSION_STRING) == 0) {
if (server->vals->protocol_id < SMB21_PROT_ID)
return 0;
} else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
return 0;
if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
return 0;
if (strcasecmp(server->hostname, ctx->server_hostname))
return 0;
if (!match_address(server, addr,
(struct sockaddr *)&ctx->srcaddr))
return 0;
if (!match_port(server, addr))
return 0;
if (!match_security(server, ctx))
return 0;
if (server->echo_interval != ctx->echo_interval * HZ)
return 0;
if (server->rdma != ctx->rdma)
return 0;
if (server->ignore_signature != ctx->ignore_signature)
return 0;
if (server->min_offload != ctx->min_offload)
return 0;
return 1;
}
cifs: Add DFS cache routines * Add new dfs_cache.[ch] files * Add new /proc/fs/cifs/dfscache file - dump current cache when read - clear current cache when writing "0" to it * Add delayed_work to periodically refresh cache entries The new interface will be used for caching DFS referrals, as well as supporting client target failover. The DFS cache is a hashtable that maps UNC paths to cache entries. A cache entry contains: - the UNC path it is mapped on - how much the the UNC path the entry consumes - flags - a Time-To-Live after which the entry expires - a list of possible targets (linked lists of UNC paths) - a "hint target" pointing the last known working target or the first target if none were tried. This hint lets cifs.ko remember and try working targets first. * Looking for an entry in the cache is done with dfs_cache_find() - if no valid entries are found, a DFS query is made, stored in the cache and returned - the full target list can be copied and returned to avoid race conditions and looped on with the help with the dfs_cache_tgt_iterator * Updating the target hint to the next target is done with dfs_cache_update_tgthint() These functions have a dfs_cache_noreq_XXX() version that doesn't fetches referrals if no entries are found. These versions don't require the tcp/ses/tcon/cifs_sb parameters as a result. Expired entries cannot be used and since they have a pretty short TTL [1] in order for them to be useful for failover the DFS cache adds a delayed work called periodically to keep them fresh. Since we might not have available connections to issue the referral request when refreshing we need to store volume_info structs with credentials and other needed info to be able to connect to the right server. 1: Windows defaults: 5mn for domain-based referrals, 30mn for regular links Signed-off-by: Paulo Alcantara <palcantara@suse.de> Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2018-11-15 02:01:21 +08:00
struct TCP_Server_Info *
cifs_find_tcp_session(struct smb3_fs_context *ctx)
{
struct TCP_Server_Info *server;
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
#ifdef CONFIG_CIFS_DFS_UPCALL
/*
* DFS failover implementation in cifs_reconnect() requires unique tcp sessions for
* DFS connections to do failover properly, so avoid sharing them with regular
* shares or even links that may connect to same server but having completely
* different failover targets.
*/
if (server->is_dfs_conn)
continue;
#endif
/*
* Skip ses channels since they're only handled in lower layers
* (e.g. cifs_send_recv).
*/
if (server->is_channel || !match_server(server, ctx))
continue;
++server->srv_count;
spin_unlock(&cifs_tcp_ses_lock);
cifs_dbg(FYI, "Existing tcp session with server found\n");
return server;
}
spin_unlock(&cifs_tcp_ses_lock);
return NULL;
}
void
cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
{
struct task_struct *task;
spin_lock(&cifs_tcp_ses_lock);
if (--server->srv_count > 0) {
spin_unlock(&cifs_tcp_ses_lock);
return;
}
/* srv_count can never go negative */
WARN_ON(server->srv_count < 0);
Make CIFS mount work in a container. Teach cifs about network namespaces, so mounting uses adresses/routing visible from the container rather than from init context. A container is a chroot on steroids that changes more than just the root filesystem the new processes see. One thing containers can isolate is "network namespaces", meaning each container can have its own set of ethernet interfaces, each with its own own IP address and routing to the outside world. And if you open a socket in _userspace_ from processes within such a container, this works fine. But sockets opened from within the kernel still use a single global networking context in a lot of places, meaning the new socket's address and routing are correct for PID 1 on the host, but are _not_ what userspace processes in the container get to use. So when you mount a network filesystem from within in a container, the mount code in the CIFS driver uses the host's networking context and not the container's networking context, so it gets the wrong address, uses the wrong routing, and may even try to go out an interface that the container can't even access... Bad stuff. This patch copies the mount process's network context into the CIFS structure that stores the rest of the server information for that mount point, and changes the socket open code to use the saved network context instead of the global network context. I.E. "when you attempt to use these addresses, do so relative to THIS set of network interfaces and routing rules, not the old global context from back before we supported containers". The big long HOWTO sets up a test environment on the assumption you've never used ocntainers before. It basically says: 1) configure and build a new kernel that has container support 2) build a new root filesystem that includes the userspace container control package (LXC) 3) package/run them under KVM (so you don't have to mess up your host system in order to play with containers). 4) set up some containers under the KVM system 5) set up contradictory routing in the KVM system and the container so that the host and the container see different things for the same address 6) try to mount a CIFS share from both contexts so you can both force it to work and force it to fail. For a long drawn out test reproduction sequence, see: http://landley.livejournal.com/47024.html http://landley.livejournal.com/47205.html http://landley.livejournal.com/47476.html Signed-off-by: Rob Landley <rlandley@parallels.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-23 05:44:05 +08:00
put_net(cifs_net_ns(server));
list_del_init(&server->tcp_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
cancel_delayed_work_sync(&server->echo);
cancel_delayed_work_sync(&server->resolve);
if (from_reconnect)
/*
* Avoid deadlock here: reconnect work calls
* cifs_put_tcp_session() at its end. Need to be sure
* that reconnect work does nothing with server pointer after
* that step.
*/
cancel_delayed_work(&server->reconnect);
else
cancel_delayed_work_sync(&server->reconnect);
spin_lock(&GlobalMid_Lock);
server->tcpStatus = CifsExiting;
spin_unlock(&GlobalMid_Lock);
cifs_crypto_secmech_release(server);
cifs_fscache_release_client_cookie(server);
kfree(server->session_key.response);
server->session_key.response = NULL;
server->session_key.len = 0;
kfree(server->hostname);
task = xchg(&server->tsk, NULL);
if (task)
send_sig(SIGKILL, task, 1);
}
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
struct TCP_Server_Info *
cifs_get_tcp_session(struct smb3_fs_context *ctx)
{
struct TCP_Server_Info *tcp_ses = NULL;
int rc;
cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
/* see if we already have a matching tcp_ses */
tcp_ses = cifs_find_tcp_session(ctx);
if (tcp_ses)
return tcp_ses;
tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
if (!tcp_ses) {
rc = -ENOMEM;
goto out_err;
}
tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
if (!tcp_ses->hostname) {
rc = -ENOMEM;
goto out_err;
}
tcp_ses->ops = ctx->ops;
tcp_ses->vals = ctx->vals;
Make CIFS mount work in a container. Teach cifs about network namespaces, so mounting uses adresses/routing visible from the container rather than from init context. A container is a chroot on steroids that changes more than just the root filesystem the new processes see. One thing containers can isolate is "network namespaces", meaning each container can have its own set of ethernet interfaces, each with its own own IP address and routing to the outside world. And if you open a socket in _userspace_ from processes within such a container, this works fine. But sockets opened from within the kernel still use a single global networking context in a lot of places, meaning the new socket's address and routing are correct for PID 1 on the host, but are _not_ what userspace processes in the container get to use. So when you mount a network filesystem from within in a container, the mount code in the CIFS driver uses the host's networking context and not the container's networking context, so it gets the wrong address, uses the wrong routing, and may even try to go out an interface that the container can't even access... Bad stuff. This patch copies the mount process's network context into the CIFS structure that stores the rest of the server information for that mount point, and changes the socket open code to use the saved network context instead of the global network context. I.E. "when you attempt to use these addresses, do so relative to THIS set of network interfaces and routing rules, not the old global context from back before we supported containers". The big long HOWTO sets up a test environment on the assumption you've never used ocntainers before. It basically says: 1) configure and build a new kernel that has container support 2) build a new root filesystem that includes the userspace container control package (LXC) 3) package/run them under KVM (so you don't have to mess up your host system in order to play with containers). 4) set up some containers under the KVM system 5) set up contradictory routing in the KVM system and the container so that the host and the container see different things for the same address 6) try to mount a CIFS share from both contexts so you can both force it to work and force it to fail. For a long drawn out test reproduction sequence, see: http://landley.livejournal.com/47024.html http://landley.livejournal.com/47205.html http://landley.livejournal.com/47476.html Signed-off-by: Rob Landley <rlandley@parallels.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-23 05:44:05 +08:00
cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
tcp_ses->noblockcnt = ctx->rootfs;
tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
tcp_ses->noautotune = ctx->noautotune;
tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
tcp_ses->rdma = ctx->rdma;
tcp_ses->in_flight = 0;
tcp_ses->max_in_flight = 0;
tcp_ses->credits = 1;
init_waitqueue_head(&tcp_ses->response_q);
init_waitqueue_head(&tcp_ses->request_q);
INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
mutex_init(&tcp_ses->srv_mutex);
memcpy(tcp_ses->workstation_RFC1001_name,
ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
memcpy(tcp_ses->server_RFC1001_name,
ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
tcp_ses->session_estab = false;
tcp_ses->sequence_number = 0;
tcp_ses->reconnect_instance = 1;
tcp_ses->lstrp = jiffies;
tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
spin_lock_init(&tcp_ses->req_lock);
INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
mutex_init(&tcp_ses->reconnect_mutex);
#ifdef CONFIG_CIFS_DFS_UPCALL
mutex_init(&tcp_ses->refpath_lock);
#endif
memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
sizeof(tcp_ses->srcaddr));
memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
sizeof(tcp_ses->dstaddr));
if (ctx->use_client_guid)
memcpy(tcp_ses->client_guid, ctx->client_guid,
SMB2_CLIENT_GUID_SIZE);
else
generate_random_uuid(tcp_ses->client_guid);
/*
* at this point we are the only ones with the pointer
* to the struct since the kernel thread not created yet
* no need to spinlock this init of tcpStatus or srv_count
*/
tcp_ses->tcpStatus = CifsNew;
++tcp_ses->srv_count;
if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
tcp_ses->echo_interval = ctx->echo_interval * HZ;
else
tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
if (tcp_ses->rdma) {
#ifndef CONFIG_CIFS_SMB_DIRECT
cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
rc = -ENOENT;
goto out_err_crypto_release;
#endif
tcp_ses->smbd_conn = smbd_get_connection(
tcp_ses, (struct sockaddr *)&ctx->dstaddr);
if (tcp_ses->smbd_conn) {
cifs_dbg(VFS, "RDMA transport established\n");
rc = 0;
goto smbd_connected;
} else {
rc = -ENOENT;
goto out_err_crypto_release;
}
}
rc = ip_connect(tcp_ses);
if (rc < 0) {
cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
goto out_err_crypto_release;
}
smbd_connected:
/*
* since we're in a cifs function already, we know that
* this will succeed. No need for try_module_get().
*/
__module_get(THIS_MODULE);
tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
tcp_ses, "cifsd");
if (IS_ERR(tcp_ses->tsk)) {
rc = PTR_ERR(tcp_ses->tsk);
cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
module_put(THIS_MODULE);
goto out_err_crypto_release;
}
tcp_ses->min_offload = ctx->min_offload;
/*
* at this point we are the only ones with the pointer
* to the struct since the kernel thread not created yet
* no need to spinlock this update of tcpStatus
*/
tcp_ses->tcpStatus = CifsNeedNegotiate;
if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
else
tcp_ses->max_credits = ctx->max_credits;
tcp_ses->nr_targets = 1;
tcp_ses->ignore_signature = ctx->ignore_signature;
/* thread spawned, put it on the list */
spin_lock(&cifs_tcp_ses_lock);
list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
cifs_fscache_get_client_cookie(tcp_ses);
/* queue echo request delayed work */
queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
/* queue dns resolution delayed work */
cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
__func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);
queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));
return tcp_ses;
out_err_crypto_release:
cifs_crypto_secmech_release(tcp_ses);
NTLM auth and sign - Define crypto hash functions and create and send keys needed for key exchange Mark dependency on crypto modules in Kconfig. Defining per structures sdesc and cifs_secmech which are used to store crypto hash functions and contexts. They are stored per smb connection and used for all auth mechs to genereate hash values and signatures. Allocate crypto hashing functions, security descriptiors, and respective contexts when a smb/tcp connection is established. Release them when a tcp/smb connection is taken down. md5 and hmac-md5 are two crypto hashing functions that are used throught the life of an smb/tcp connection by various functions that calcualte signagure and ntlmv2 hash, HMAC etc. structure ntlmssp_auth is defined as per smb connection. ntlmssp_auth holds ciphertext which is genereated by rc4/arc4 encryption of secondary key, a nonce using ntlmv2 session key and sent in the session key field of the type 3 message sent by the client during ntlmssp negotiation/exchange A key is exchanged with the server if client indicates so in flags in type 1 messsage and server agrees in flag in type 2 message of ntlmssp negotiation. If both client and agree, a key sent by client in type 3 message of ntlmssp negotiation in the session key field. The key is a ciphertext generated off of secondary key, a nonce, using ntlmv2 hash via rc4/arc4. Signing works for ntlmssp in this patch. The sequence number within the server structure needs to be zero until session is established i.e. till type 3 packet of ntlmssp exchange of a to be very first smb session on that smb connection is sent. Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-10-22 03:25:08 +08:00
Make CIFS mount work in a container. Teach cifs about network namespaces, so mounting uses adresses/routing visible from the container rather than from init context. A container is a chroot on steroids that changes more than just the root filesystem the new processes see. One thing containers can isolate is "network namespaces", meaning each container can have its own set of ethernet interfaces, each with its own own IP address and routing to the outside world. And if you open a socket in _userspace_ from processes within such a container, this works fine. But sockets opened from within the kernel still use a single global networking context in a lot of places, meaning the new socket's address and routing are correct for PID 1 on the host, but are _not_ what userspace processes in the container get to use. So when you mount a network filesystem from within in a container, the mount code in the CIFS driver uses the host's networking context and not the container's networking context, so it gets the wrong address, uses the wrong routing, and may even try to go out an interface that the container can't even access... Bad stuff. This patch copies the mount process's network context into the CIFS structure that stores the rest of the server information for that mount point, and changes the socket open code to use the saved network context instead of the global network context. I.E. "when you attempt to use these addresses, do so relative to THIS set of network interfaces and routing rules, not the old global context from back before we supported containers". The big long HOWTO sets up a test environment on the assumption you've never used ocntainers before. It basically says: 1) configure and build a new kernel that has container support 2) build a new root filesystem that includes the userspace container control package (LXC) 3) package/run them under KVM (so you don't have to mess up your host system in order to play with containers). 4) set up some containers under the KVM system 5) set up contradictory routing in the KVM system and the container so that the host and the container see different things for the same address 6) try to mount a CIFS share from both contexts so you can both force it to work and force it to fail. For a long drawn out test reproduction sequence, see: http://landley.livejournal.com/47024.html http://landley.livejournal.com/47205.html http://landley.livejournal.com/47476.html Signed-off-by: Rob Landley <rlandley@parallels.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-23 05:44:05 +08:00
put_net(cifs_net_ns(tcp_ses));
out_err:
if (tcp_ses) {
kfree(tcp_ses->hostname);
if (tcp_ses->ssocket)
sock_release(tcp_ses->ssocket);
kfree(tcp_ses);
}
return ERR_PTR(rc);
}
static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
{
if (ctx->sectype != Unspecified &&
ctx->sectype != ses->sectype)
return 0;
/*
* If an existing session is limited to less channels than
* requested, it should not be reused
*/
if (ses->chan_max < ctx->max_channels)
return 0;
switch (ses->sectype) {
case Kerberos:
if (!uid_eq(ctx->cred_uid, ses->cred_uid))
return 0;
break;
default:
/* NULL username means anonymous session */
if (ses->user_name == NULL) {
if (!ctx->nullauth)
return 0;
break;
}
/* anything else takes username/password */
if (strncmp(ses->user_name,
ctx->username ? ctx->username : "",
CIFS_MAX_USERNAME_LEN))
return 0;
if ((ctx->username && strlen(ctx->username) != 0) &&
ses->password != NULL &&
strncmp(ses->password,
ctx->password ? ctx->password : "",
CIFS_MAX_PASSWORD_LEN))
return 0;
}
return 1;
}
/**
* cifs_setup_ipc - helper to setup the IPC tcon for the session
* @ses: smb session to issue the request on
* @ctx: the superblock configuration context to use for building the
* new tree connection for the IPC (interprocess communication RPC)
*
* A new IPC connection is made and stored in the session
* tcon_ipc. The IPC tcon has the same lifetime as the session.
*/
static int
cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
{
int rc = 0, xid;
struct cifs_tcon *tcon;
char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
bool seal = false;
struct TCP_Server_Info *server = ses->server;
/*
* If the mount request that resulted in the creation of the
* session requires encryption, force IPC to be encrypted too.
*/
if (ctx->seal) {
if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
seal = true;
else {
cifs_server_dbg(VFS,
"IPC: server doesn't support encryption\n");
return -EOPNOTSUPP;
}
}
tcon = tconInfoAlloc();
if (tcon == NULL)
return -ENOMEM;
scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
xid = get_xid();
tcon->ses = ses;
tcon->ipc = true;
tcon->seal = seal;
rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
free_xid(xid);
if (rc) {
cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
tconInfoFree(tcon);
goto out;
}
cifs_dbg(FYI, "IPC tcon rc = %d ipc tid = %d\n", rc, tcon->tid);
ses->tcon_ipc = tcon;
out:
return rc;
}
/**
* cifs_free_ipc - helper to release the session IPC tcon
* @ses: smb session to unmount the IPC from
*
* Needs to be called everytime a session is destroyed.
*
* On session close, the IPC is closed and the server must release all tcons of the session.
* No need to send a tree disconnect here.
*
* Besides, it will make the server to not close durable and resilient files on session close, as
* specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
*/
static int
cifs_free_ipc(struct cifs_ses *ses)
{
struct cifs_tcon *tcon = ses->tcon_ipc;
if (tcon == NULL)
return 0;
tconInfoFree(tcon);
ses->tcon_ipc = NULL;
return 0;
}
static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
struct cifs_ses *ses;
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
if (ses->status == CifsExiting)
continue;
if (!match_session(ses, ctx))
continue;
++ses->ses_count;
spin_unlock(&cifs_tcp_ses_lock);
return ses;
}
spin_unlock(&cifs_tcp_ses_lock);
return NULL;
}
void cifs_put_smb_ses(struct cifs_ses *ses)
{
unsigned int rc, xid;
struct TCP_Server_Info *server = ses->server;
cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
spin_lock(&cifs_tcp_ses_lock);
if (ses->status == CifsExiting) {
spin_unlock(&cifs_tcp_ses_lock);
return;
}
cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
cifs_dbg(FYI, "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->treeName : "NONE");
if (--ses->ses_count > 0) {
spin_unlock(&cifs_tcp_ses_lock);
return;
}
spin_unlock(&cifs_tcp_ses_lock);
/* ses_count can never go negative */
WARN_ON(ses->ses_count < 0);
spin_lock(&GlobalMid_Lock);
if (ses->status == CifsGood)
ses->status = CifsExiting;
spin_unlock(&GlobalMid_Lock);
cifs_free_ipc(ses);
if (ses->status == CifsExiting && server->ops->logoff) {
xid = get_xid();
rc = server->ops->logoff(xid, ses);
if (rc)
cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
__func__, rc);
_free_xid(xid);
}
spin_lock(&cifs_tcp_ses_lock);
list_del_init(&ses->smb_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
/* close any extra channels */
if (ses->chan_count > 1) {
int i;
for (i = 1; i < ses->chan_count; i++)
cifs_put_tcp_session(ses->chans[i].server, 0);
}
sesInfoFree(ses);
cifs_put_tcp_session(server, 0);
}
#ifdef CONFIG_KEYS
/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
/* Populate username and pw fields from keyring if possible */
static int
cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
{
int rc = 0;
int is_domain = 0;
const char *delim, *payload;
char *desc;
ssize_t len;
struct key *key;
struct TCP_Server_Info *server = ses->server;
struct sockaddr_in *sa;
struct sockaddr_in6 *sa6;
const struct user_key_payload *upayload;
desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
if (!desc)
return -ENOMEM;
/* try to find an address key first */
switch (server->dstaddr.ss_family) {
case AF_INET:
sa = (struct sockaddr_in *)&server->dstaddr;
sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
break;
case AF_INET6:
sa6 = (struct sockaddr_in6 *)&server->dstaddr;
sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
break;
default:
cifs_dbg(FYI, "Bad ss_family (%hu)\n",
server->dstaddr.ss_family);
rc = -EINVAL;
goto out_err;
}
cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
key = request_key(&key_type_logon, desc, "");
if (IS_ERR(key)) {
if (!ses->domainName) {
cifs_dbg(FYI, "domainName is NULL\n");
rc = PTR_ERR(key);
goto out_err;
}
/* didn't work, try to find a domain key */
sprintf(desc, "cifs:d:%s", ses->domainName);
cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
key = request_key(&key_type_logon, desc, "");
if (IS_ERR(key)) {
rc = PTR_ERR(key);
goto out_err;
}
is_domain = 1;
}
down_read(&key->sem);
KEYS: Differentiate uses of rcu_dereference_key() and user_key_payload() rcu_dereference_key() and user_key_payload() are currently being used in two different, incompatible ways: (1) As a wrapper to rcu_dereference() - when only the RCU read lock used to protect the key. (2) As a wrapper to rcu_dereference_protected() - when the key semaphor is used to protect the key and the may be being modified. Fix this by splitting both of the key wrappers to produce: (1) RCU accessors for keys when caller has the key semaphore locked: dereference_key_locked() user_key_payload_locked() (2) RCU accessors for keys when caller holds the RCU read lock: dereference_key_rcu() user_key_payload_rcu() This should fix following warning in the NFS idmapper =============================== [ INFO: suspicious RCU usage. ] 4.10.0 #1 Tainted: G W ------------------------------- ./include/keys/user-type.h:53 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 1 lock held by mount.nfs/5987: #0: (rcu_read_lock){......}, at: [<d000000002527abc>] nfs_idmap_get_key+0x15c/0x420 [nfsv4] stack backtrace: CPU: 1 PID: 5987 Comm: mount.nfs Tainted: G W 4.10.0 #1 Call Trace: dump_stack+0xe8/0x154 (unreliable) lockdep_rcu_suspicious+0x140/0x190 nfs_idmap_get_key+0x380/0x420 [nfsv4] nfs_map_name_to_uid+0x2a0/0x3b0 [nfsv4] decode_getfattr_attrs+0xfac/0x16b0 [nfsv4] decode_getfattr_generic.constprop.106+0xbc/0x150 [nfsv4] nfs4_xdr_dec_lookup_root+0xac/0xb0 [nfsv4] rpcauth_unwrap_resp+0xe8/0x140 [sunrpc] call_decode+0x29c/0x910 [sunrpc] __rpc_execute+0x140/0x8f0 [sunrpc] rpc_run_task+0x170/0x200 [sunrpc] nfs4_call_sync_sequence+0x68/0xa0 [nfsv4] _nfs4_lookup_root.isra.44+0xd0/0xf0 [nfsv4] nfs4_lookup_root+0xe0/0x350 [nfsv4] nfs4_lookup_root_sec+0x70/0xa0 [nfsv4] nfs4_find_root_sec+0xc4/0x100 [nfsv4] nfs4_proc_get_rootfh+0x5c/0xf0 [nfsv4] nfs4_get_rootfh+0x6c/0x190 [nfsv4] nfs4_server_common_setup+0xc4/0x260 [nfsv4] nfs4_create_server+0x278/0x3c0 [nfsv4] nfs4_remote_mount+0x50/0xb0 [nfsv4] mount_fs+0x74/0x210 vfs_kern_mount+0x78/0x220 nfs_do_root_mount+0xb0/0x140 [nfsv4] nfs4_try_mount+0x60/0x100 [nfsv4] nfs_fs_mount+0x5ec/0xda0 [nfs] mount_fs+0x74/0x210 vfs_kern_mount+0x78/0x220 do_mount+0x254/0xf70 SyS_mount+0x94/0x100 system_call+0x38/0xe0 Reported-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-03-01 23:11:23 +08:00
upayload = user_key_payload_locked(key);
if (IS_ERR_OR_NULL(upayload)) {
rc = upayload ? PTR_ERR(upayload) : -EINVAL;
goto out_key_put;
}
/* find first : in payload */
payload = upayload->data;
delim = strnchr(payload, upayload->datalen, ':');
cifs_dbg(FYI, "payload=%s\n", payload);
if (!delim) {
cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
upayload->datalen);
rc = -EINVAL;
goto out_key_put;
}
len = delim - payload;
if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
len);
rc = -EINVAL;
goto out_key_put;
}
ctx->username = kstrndup(payload, len, GFP_KERNEL);
if (!ctx->username) {
cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
len);
rc = -ENOMEM;
goto out_key_put;
}
cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
len = key->datalen - (len + 1);
if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
rc = -EINVAL;
kfree(ctx->username);
ctx->username = NULL;
goto out_key_put;
}
++delim;
ctx->password = kstrndup(delim, len, GFP_KERNEL);
if (!ctx->password) {
cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
len);
rc = -ENOMEM;
kfree(ctx->username);
ctx->username = NULL;
goto out_key_put;
}
/*
* If we have a domain key then we must set the domainName in the
* for the request.
*/
if (is_domain && ses->domainName) {
ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
if (!ctx->domainname) {
cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
len);
rc = -ENOMEM;
kfree(ctx->username);
ctx->username = NULL;
kfree_sensitive(ctx->password);
ctx->password = NULL;
goto out_key_put;
}
}
out_key_put:
up_read(&key->sem);
key_put(key);
out_err:
kfree(desc);
cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
return rc;
}
#else /* ! CONFIG_KEYS */
static inline int
cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
struct cifs_ses *ses __attribute__((unused)))
{
return -ENOSYS;
}
#endif /* CONFIG_KEYS */
/**
* cifs_get_smb_ses - get a session matching @ctx data from @server
* @server: server to setup the session to
* @ctx: superblock configuration context to use to setup the session
*
* This function assumes it is being called from cifs_mount() where we
* already got a server reference (server refcount +1). See
* cifs_get_tcon() for refcount explanations.
*/
struct cifs_ses *
cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
{
int rc = -ENOMEM;
unsigned int xid;
struct cifs_ses *ses;
struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
xid = get_xid();
ses = cifs_find_smb_ses(server, ctx);
if (ses) {
cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
ses->status);
mutex_lock(&ses->session_mutex);
rc = cifs_negotiate_protocol(xid, ses);
if (rc) {
mutex_unlock(&ses->session_mutex);
/* problem -- put our ses reference */
cifs_put_smb_ses(ses);
free_xid(xid);
return ERR_PTR(rc);
}
if (ses->need_reconnect) {
cifs_dbg(FYI, "Session needs reconnect\n");
rc = cifs_setup_session(xid, ses,
ctx->local_nls);
if (rc) {
mutex_unlock(&ses->session_mutex);
/* problem -- put our reference */
cifs_put_smb_ses(ses);
free_xid(xid);
return ERR_PTR(rc);
}
}
mutex_unlock(&ses->session_mutex);
/* existing SMB ses has a server reference already */
cifs_put_tcp_session(server, 0);
free_xid(xid);
return ses;
}
cifs_dbg(FYI, "Existing smb sess not found\n");
ses = sesInfoAlloc();
if (ses == NULL)
goto get_ses_fail;
/* new SMB session uses our server ref */
ses->server = server;
if (server->dstaddr.ss_family == AF_INET6)
sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
else
sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
if (ctx->username) {
ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
if (!ses->user_name)
goto get_ses_fail;
}
/* ctx->password freed at unmount */
if (ctx->password) {
ses->password = kstrdup(ctx->password, GFP_KERNEL);
if (!ses->password)
goto get_ses_fail;
}
if (ctx->domainname) {
ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
if (!ses->domainName)
goto get_ses_fail;
}
if (ctx->workstation_name) {
ses->workstation_name = kstrdup(ctx->workstation_name,
GFP_KERNEL);
if (!ses->workstation_name)
goto get_ses_fail;
}
if (ctx->domainauto)
ses->domainAuto = ctx->domainauto;
ses->cred_uid = ctx->cred_uid;
ses->linux_uid = ctx->linux_uid;
ses->sectype = ctx->sectype;
ses->sign = ctx->sign;
mutex_lock(&ses->session_mutex);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
/* add server as first channel */
ses->chans[0].server = server;
ses->chan_count = 1;
ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
rc = cifs_negotiate_protocol(xid, ses);
if (!rc)
rc = cifs_setup_session(xid, ses, ctx->local_nls);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
/* each channel uses a different signing key */
memcpy(ses->chans[0].signkey, ses->smb3signingkey,
sizeof(ses->smb3signingkey));
mutex_unlock(&ses->session_mutex);
if (rc)
goto get_ses_fail;
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
/* success, put it on the list and add it as first channel */
spin_lock(&cifs_tcp_ses_lock);
list_add(&ses->smb_ses_list, &server->smb_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
free_xid(xid);
cifs_setup_ipc(ses, ctx);
return ses;
get_ses_fail:
sesInfoFree(ses);
free_xid(xid);
return ERR_PTR(rc);
}
static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
if (tcon->tidStatus == CifsExiting)
return 0;
if (strncmp(tcon->treeName, ctx->UNC, MAX_TREE_SIZE))
return 0;
if (tcon->seal != ctx->seal)
return 0;
if (tcon->snapshot_time != ctx->snapshot_time)
return 0;
if (tcon->handle_timeout != ctx->handle_timeout)
return 0;
if (tcon->no_lease != ctx->no_lease)
return 0;
if (tcon->nodelete != ctx->nodelete)
return 0;
return 1;
}
static struct cifs_tcon *
cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
{
struct list_head *tmp;
struct cifs_tcon *tcon;
spin_lock(&cifs_tcp_ses_lock);
list_for_each(tmp, &ses->tcon_list) {
tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
if (!match_tcon(tcon, ctx))
continue;
++tcon->tc_count;
spin_unlock(&cifs_tcp_ses_lock);
return tcon;
}
spin_unlock(&cifs_tcp_ses_lock);
return NULL;
}
void
cifs_put_tcon(struct cifs_tcon *tcon)
{
unsigned int xid;
struct cifs_ses *ses;
/*
* IPC tcon share the lifetime of their session and are
* destroyed in the session put function
*/
if (tcon == NULL || tcon->ipc)
return;
ses = tcon->ses;
cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
spin_lock(&cifs_tcp_ses_lock);
if (--tcon->tc_count > 0) {
spin_unlock(&cifs_tcp_ses_lock);
return;
}
/* tc_count can never go negative */
WARN_ON(tcon->tc_count < 0);
if (tcon->use_witness) {
int rc;
rc = cifs_swn_unregister(tcon);
if (rc < 0) {
cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
__func__, rc);
}
}
list_del_init(&tcon->tcon_list);
spin_unlock(&cifs_tcp_ses_lock);
xid = get_xid();
if (ses->server->ops->tree_disconnect)
ses->server->ops->tree_disconnect(xid, tcon);
_free_xid(xid);
cifs_fscache_release_super_cookie(tcon);
tconInfoFree(tcon);
cifs_put_smb_ses(ses);
}
/**
* cifs_get_tcon - get a tcon matching @ctx data from @ses
* @ses: smb session to issue the request on
* @ctx: the superblock configuration context to use for building the
*
* - tcon refcount is the number of mount points using the tcon.
* - ses refcount is the number of tcon using the session.
*
* 1. This function assumes it is being called from cifs_mount() where
* we already got a session reference (ses refcount +1).
*
* 2. Since we're in the context of adding a mount point, the end
* result should be either:
*
* a) a new tcon already allocated with refcount=1 (1 mount point) and
* its session refcount incremented (1 new tcon). This +1 was
* already done in (1).
*
* b) an existing tcon with refcount+1 (add a mount point to it) and
* identical ses refcount (no new tcon). Because of (1) we need to
* decrement the ses refcount.
*/
static struct cifs_tcon *
cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
{
int rc, xid;
struct cifs_tcon *tcon;
tcon = cifs_find_tcon(ses, ctx);
if (tcon) {
/*
* tcon has refcount already incremented but we need to
* decrement extra ses reference gotten by caller (case b)
*/
cifs_dbg(FYI, "Found match on UNC path\n");
cifs_put_smb_ses(ses);
return tcon;
}
if (!ses->server->ops->tree_connect) {
rc = -ENOSYS;
goto out_fail;
}
tcon = tconInfoAlloc();
if (tcon == NULL) {
rc = -ENOMEM;
goto out_fail;
}
if (ctx->snapshot_time) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"Use SMB2 or later for snapshot mount option\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else
tcon->snapshot_time = ctx->snapshot_time;
}
if (ctx->handle_timeout) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"Use SMB2.1 or later for handle timeout option\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else
tcon->handle_timeout = ctx->handle_timeout;
}
tcon->ses = ses;
if (ctx->password) {
tcon->password = kstrdup(ctx->password, GFP_KERNEL);
if (!tcon->password) {
rc = -ENOMEM;
goto out_fail;
}
}
if (ctx->seal) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB3 or later required for encryption\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else if (tcon->ses->server->capabilities &
SMB2_GLOBAL_CAP_ENCRYPTION)
tcon->seal = true;
else {
cifs_dbg(VFS, "Encryption is not supported on share\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
}
if (ctx->linux_ext) {
if (ses->server->posix_ext_supported) {
tcon->posix_extensions = true;
pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
} else {
cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
}
/*
* BB Do we need to wrap session_mutex around this TCon call and Unix
* SetFS as we do on SessSetup and reconnect?
*/
xid = get_xid();
rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
ctx->local_nls);
free_xid(xid);
cifs_dbg(FYI, "Tcon rc = %d\n", rc);
if (rc)
goto out_fail;
tcon->use_persistent = false;
/* check if SMB2 or later, CIFS does not support persistent handles */
if (ctx->persistent) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB3 or later required for persistent handles\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else if (ses->server->capabilities &
SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
tcon->use_persistent = true;
else /* persistent handles requested but not supported */ {
cifs_dbg(VFS,
"Persistent handles not supported on share\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
} else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
&& (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
&& (ctx->nopersistent == false)) {
cifs_dbg(FYI, "enabling persistent handles\n");
tcon->use_persistent = true;
} else if (ctx->resilient) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB2.1 or later required for resilient handles\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
tcon->use_resilient = true;
}
tcon->use_witness = false;
if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
/*
* Set witness in use flag in first place
* to retry registration in the echo task
*/
tcon->use_witness = true;
/* And try to register immediately */
rc = cifs_swn_register(tcon);
if (rc < 0) {
cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
goto out_fail;
}
} else {
/* TODO: try to extend for non-cluster uses (eg multichannel) */
cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
} else {
cifs_dbg(VFS, "SMB3 or later required for witness option\n");
rc = -EOPNOTSUPP;
goto out_fail;
}
}
/* If the user really knows what they are doing they can override */
if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
if (ctx->cache_ro)
cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
else if (ctx->cache_rw)
cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
}
if (ctx->no_lease) {
if (ses->server->vals->protocol_id == 0) {
cifs_dbg(VFS,
"SMB2 or later required for nolease option\n");
rc = -EOPNOTSUPP;
goto out_fail;
} else
tcon->no_lease = ctx->no_lease;
}
/*
* We can have only one retry value for a connection to a share so for
* resources mounted more than once to the same server share the last
* value passed in for the retry flag is used.
*/
tcon->retry = ctx->retry;
tcon->nocase = ctx->nocase;
if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
tcon->nohandlecache = ctx->nohandlecache;
else
tcon->nohandlecache = true;
tcon->nodelete = ctx->nodelete;
tcon->local_lease = ctx->local_lease;
INIT_LIST_HEAD(&tcon->pending_opens);
spin_lock(&cifs_tcp_ses_lock);
list_add(&tcon->tcon_list, &ses->tcon_list);
spin_unlock(&cifs_tcp_ses_lock);
return tcon;
out_fail:
tconInfoFree(tcon);
return ERR_PTR(rc);
}
void
cifs_put_tlink(struct tcon_link *tlink)
{
if (!tlink || IS_ERR(tlink))
return;
if (!atomic_dec_and_test(&tlink->tl_count) ||
test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
tlink->tl_time = jiffies;
return;
}
if (!IS_ERR(tlink_tcon(tlink)))
cifs_put_tcon(tlink_tcon(tlink));
kfree(tlink);
return;
}
static int
compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
{
struct cifs_sb_info *old = CIFS_SB(sb);
struct cifs_sb_info *new = mnt_data->cifs_sb;
unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
return 0;
if (old->mnt_cifs_serverino_autodisabled)
newflags &= ~CIFS_MOUNT_SERVER_INUM;
if (oldflags != newflags)
return 0;
/*
* We want to share sb only if we don't specify an r/wsize or
* specified r/wsize is greater than or equal to existing one.
*/
if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
return 0;
if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
return 0;
if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
!gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
return 0;
if (old->ctx->file_mode != new->ctx->file_mode ||
old->ctx->dir_mode != new->ctx->dir_mode)
return 0;
if (strcmp(old->local_nls->charset, new->local_nls->charset))
return 0;
if (old->ctx->acregmax != new->ctx->acregmax)
return 0;
if (old->ctx->acdirmax != new->ctx->acdirmax)
return 0;
return 1;
}
static int
match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
{
struct cifs_sb_info *old = CIFS_SB(sb);
struct cifs_sb_info *new = mnt_data->cifs_sb;
bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
old->prepath;
bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
new->prepath;
if (old_set && new_set && !strcmp(new->prepath, old->prepath))
return 1;
else if (!old_set && !new_set)
return 1;
return 0;
}
int
cifs_match_super(struct super_block *sb, void *data)
{
struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data;
struct smb3_fs_context *ctx;
struct cifs_sb_info *cifs_sb;
struct TCP_Server_Info *tcp_srv;
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct tcon_link *tlink;
int rc = 0;
spin_lock(&cifs_tcp_ses_lock);
cifs_sb = CIFS_SB(sb);
tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
if (tlink == NULL) {
/* can not match superblock if tlink were ever null */
spin_unlock(&cifs_tcp_ses_lock);
return 0;
}
tcon = tlink_tcon(tlink);
ses = tcon->ses;
tcp_srv = ses->server;
ctx = mnt_data->ctx;
if (!match_server(tcp_srv, ctx) ||
!match_session(ses, ctx) ||
!match_tcon(tcon, ctx) ||
!match_prepath(sb, mnt_data)) {
rc = 0;
goto out;
}
rc = compare_mount_options(sb, mnt_data);
out:
spin_unlock(&cifs_tcp_ses_lock);
cifs_put_tlink(tlink);
return rc;
}
lockdep: annotate cifs in-kernel sockets Put CIFS sockets in their own class to avoid some lockdep warnings. CIFS sockets are not exposed to user-space, and so are not subject to the same deadlock scenarios. A similar change was made a couple of years ago for RPC sockets in commit ed07536ed6731775219c1df7fa26a7588753e693. This patch should prevent lockdep false-positives like this one: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.18-98.el5.jtltest.38.bz456320.1debug #1 ------------------------------------------------------- test5/2483 is trying to acquire lock: (sk_lock-AF_INET){--..}, at: [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f but task is already holding lock: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&inode->i_alloc_sem){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800a4e36>] down_write+0x3c/0x68 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff80060116>] system_call+0x7e/0x83 [<ffffffffffffffff>] 0xffffffffffffffff -> #2 (&sysfs_inode_imutex_key){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff800a819d>] __lock_acquire+0x9ca/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff8010fc67>] sysfs_create_dir+0x58/0x76 [<ffffffff8015144c>] kobject_add+0xdb/0x198 [<ffffffff801be765>] class_device_add+0xb2/0x465 [<ffffffff8005a6ff>] kobject_get+0x12/0x17 [<ffffffff80225265>] register_netdevice+0x270/0x33e [<ffffffff8022538c>] register_netdev+0x59/0x67 [<ffffffff80464d40>] net_olddevs_init+0xb/0xac [<ffffffff80448a79>] init+0x1f9/0x2fc [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff80067f86>] trace_hardirqs_on_thunk+0x35/0x37 [<ffffffff80061079>] child_rip+0xa/0x11 [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff80179a59>] acpi_ds_init_one_object+0x0/0x80 [<ffffffff80448880>] init+0x0/0x2fc [<ffffffff8006106f>] child_rip+0x0/0x11 [<ffffffffffffffff>] 0xffffffffffffffff -> #1 (rtnl_mutex){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff802451b0>] do_ip_setsockopt+0x6d1/0x9bf [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff8006a85e>] do_page_fault+0x503/0x835 [<ffffffff8012cbf6>] socket_has_perm+0x5b/0x68 [<ffffffff80245556>] ip_setsockopt+0x22/0x78 [<ffffffff8021c973>] sys_setsockopt+0x91/0xb7 [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff -> #0 (sk_lock-AF_INET){--..}: [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] MD5Final+0xaf/0xc2 [cifs] [<ffffffff884032ec>] cifs_calculate_signature+0x55/0x69 [cifs] [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] smb_send+0xa3/0x151 [cifs] [<ffffffff883ff5de>] SendReceive+0x1a2/0x448 [cifs] [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] CIFSSMBSetEOF+0x20d/0x25b [cifs] [<ffffffff883fa430>] cifs_set_file_size+0x110/0x3b7 [cifs] [<ffffffff883faa89>] cifs_setattr+0x3b2/0x6f6 [cifs] [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff other info that might help us debug this: 2 locks held by test5/2483: #0: (&inode->i_mutex){--..}, at: [<ffffffff800e3582>] do_truncate+0x45/0x6b #1: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 stack backtrace: Call Trace: [<ffffffff800a6a7b>] print_circular_bug_tail+0x65/0x6e [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] :cifs:MD5Final+0xaf/0xc2 [<ffffffff884032ec>] :cifs:cifs_calculate_signature+0x55/0x69 [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] :cifs:smb_send+0xa3/0x151 [<ffffffff883ff5de>] :cifs:SendReceive+0x1a2/0x448 [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] :cifs:CIFSSMBSetEOF+0x20d/0x25b [<ffffffff883fa430>] :cifs:cifs_set_file_size+0x110/0x3b7 [<ffffffff883faa89>] :cifs:cifs_setattr+0x3b2/0x6f6 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-07-23 22:11:19 +08:00
#ifdef CONFIG_DEBUG_LOCK_ALLOC
static struct lock_class_key cifs_key[2];
static struct lock_class_key cifs_slock_key[2];
static inline void
cifs_reclassify_socket4(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(!sock_allow_reclassification(sk));
lockdep: annotate cifs in-kernel sockets Put CIFS sockets in their own class to avoid some lockdep warnings. CIFS sockets are not exposed to user-space, and so are not subject to the same deadlock scenarios. A similar change was made a couple of years ago for RPC sockets in commit ed07536ed6731775219c1df7fa26a7588753e693. This patch should prevent lockdep false-positives like this one: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.18-98.el5.jtltest.38.bz456320.1debug #1 ------------------------------------------------------- test5/2483 is trying to acquire lock: (sk_lock-AF_INET){--..}, at: [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f but task is already holding lock: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&inode->i_alloc_sem){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800a4e36>] down_write+0x3c/0x68 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff80060116>] system_call+0x7e/0x83 [<ffffffffffffffff>] 0xffffffffffffffff -> #2 (&sysfs_inode_imutex_key){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff800a819d>] __lock_acquire+0x9ca/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff8010fc67>] sysfs_create_dir+0x58/0x76 [<ffffffff8015144c>] kobject_add+0xdb/0x198 [<ffffffff801be765>] class_device_add+0xb2/0x465 [<ffffffff8005a6ff>] kobject_get+0x12/0x17 [<ffffffff80225265>] register_netdevice+0x270/0x33e [<ffffffff8022538c>] register_netdev+0x59/0x67 [<ffffffff80464d40>] net_olddevs_init+0xb/0xac [<ffffffff80448a79>] init+0x1f9/0x2fc [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff80067f86>] trace_hardirqs_on_thunk+0x35/0x37 [<ffffffff80061079>] child_rip+0xa/0x11 [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff80179a59>] acpi_ds_init_one_object+0x0/0x80 [<ffffffff80448880>] init+0x0/0x2fc [<ffffffff8006106f>] child_rip+0x0/0x11 [<ffffffffffffffff>] 0xffffffffffffffff -> #1 (rtnl_mutex){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff802451b0>] do_ip_setsockopt+0x6d1/0x9bf [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff8006a85e>] do_page_fault+0x503/0x835 [<ffffffff8012cbf6>] socket_has_perm+0x5b/0x68 [<ffffffff80245556>] ip_setsockopt+0x22/0x78 [<ffffffff8021c973>] sys_setsockopt+0x91/0xb7 [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff -> #0 (sk_lock-AF_INET){--..}: [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] MD5Final+0xaf/0xc2 [cifs] [<ffffffff884032ec>] cifs_calculate_signature+0x55/0x69 [cifs] [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] smb_send+0xa3/0x151 [cifs] [<ffffffff883ff5de>] SendReceive+0x1a2/0x448 [cifs] [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] CIFSSMBSetEOF+0x20d/0x25b [cifs] [<ffffffff883fa430>] cifs_set_file_size+0x110/0x3b7 [cifs] [<ffffffff883faa89>] cifs_setattr+0x3b2/0x6f6 [cifs] [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff other info that might help us debug this: 2 locks held by test5/2483: #0: (&inode->i_mutex){--..}, at: [<ffffffff800e3582>] do_truncate+0x45/0x6b #1: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 stack backtrace: Call Trace: [<ffffffff800a6a7b>] print_circular_bug_tail+0x65/0x6e [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] :cifs:MD5Final+0xaf/0xc2 [<ffffffff884032ec>] :cifs:cifs_calculate_signature+0x55/0x69 [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] :cifs:smb_send+0xa3/0x151 [<ffffffff883ff5de>] :cifs:SendReceive+0x1a2/0x448 [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] :cifs:CIFSSMBSetEOF+0x20d/0x25b [<ffffffff883fa430>] :cifs:cifs_set_file_size+0x110/0x3b7 [<ffffffff883faa89>] :cifs:cifs_setattr+0x3b2/0x6f6 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-07-23 22:11:19 +08:00
sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
&cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
}
static inline void
cifs_reclassify_socket6(struct socket *sock)
{
struct sock *sk = sock->sk;
BUG_ON(!sock_allow_reclassification(sk));
lockdep: annotate cifs in-kernel sockets Put CIFS sockets in their own class to avoid some lockdep warnings. CIFS sockets are not exposed to user-space, and so are not subject to the same deadlock scenarios. A similar change was made a couple of years ago for RPC sockets in commit ed07536ed6731775219c1df7fa26a7588753e693. This patch should prevent lockdep false-positives like this one: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.18-98.el5.jtltest.38.bz456320.1debug #1 ------------------------------------------------------- test5/2483 is trying to acquire lock: (sk_lock-AF_INET){--..}, at: [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f but task is already holding lock: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&inode->i_alloc_sem){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800a4e36>] down_write+0x3c/0x68 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff80060116>] system_call+0x7e/0x83 [<ffffffffffffffff>] 0xffffffffffffffff -> #2 (&sysfs_inode_imutex_key){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff800a819d>] __lock_acquire+0x9ca/0xadf [<ffffffff8010f6df>] create_dir+0x26/0x1d7 [<ffffffff8010fc67>] sysfs_create_dir+0x58/0x76 [<ffffffff8015144c>] kobject_add+0xdb/0x198 [<ffffffff801be765>] class_device_add+0xb2/0x465 [<ffffffff8005a6ff>] kobject_get+0x12/0x17 [<ffffffff80225265>] register_netdevice+0x270/0x33e [<ffffffff8022538c>] register_netdev+0x59/0x67 [<ffffffff80464d40>] net_olddevs_init+0xb/0xac [<ffffffff80448a79>] init+0x1f9/0x2fc [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff80067f86>] trace_hardirqs_on_thunk+0x35/0x37 [<ffffffff80061079>] child_rip+0xa/0x11 [<ffffffff80068885>] _spin_unlock_irq+0x24/0x27 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff80179a59>] acpi_ds_init_one_object+0x0/0x80 [<ffffffff80448880>] init+0x0/0x2fc [<ffffffff8006106f>] child_rip+0x0/0x11 [<ffffffffffffffff>] 0xffffffffffffffff -> #1 (rtnl_mutex){--..}: [<ffffffff800a817c>] __lock_acquire+0x9a9/0xadf [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff800671c0>] mutex_lock_nested+0x104/0x29c [<ffffffff8025acf8>] ip_mc_leave_group+0x23/0xb7 [<ffffffff802451b0>] do_ip_setsockopt+0x6d1/0x9bf [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff800a575e>] lock_release_holdtime+0x27/0x48 [<ffffffff8006a85e>] do_page_fault+0x503/0x835 [<ffffffff8012cbf6>] socket_has_perm+0x5b/0x68 [<ffffffff80245556>] ip_setsockopt+0x22/0x78 [<ffffffff8021c973>] sys_setsockopt+0x91/0xb7 [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff -> #0 (sk_lock-AF_INET){--..}: [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] MD5Final+0xaf/0xc2 [cifs] [<ffffffff884032ec>] cifs_calculate_signature+0x55/0x69 [cifs] [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] smb_send+0xa3/0x151 [cifs] [<ffffffff883ff5de>] SendReceive+0x1a2/0x448 [cifs] [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] CIFSSMBSetEOF+0x20d/0x25b [cifs] [<ffffffff883fa430>] cifs_set_file_size+0x110/0x3b7 [cifs] [<ffffffff883faa89>] cifs_setattr+0x3b2/0x6f6 [cifs] [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf [<ffffffffffffffff>] 0xffffffffffffffff other info that might help us debug this: 2 locks held by test5/2483: #0: (&inode->i_mutex){--..}, at: [<ffffffff800e3582>] do_truncate+0x45/0x6b #1: (&inode->i_alloc_sem){--..}, at: [<ffffffff8002e454>] notify_change+0xf5/0x2e0 stack backtrace: Call Trace: [<ffffffff800a6a7b>] print_circular_bug_tail+0x65/0x6e [<ffffffff800a5037>] print_stack_trace+0x59/0x68 [<ffffffff800a8092>] __lock_acquire+0x8bf/0xadf [<ffffffff800a8a72>] lock_acquire+0x55/0x70 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80035466>] lock_sock+0xd4/0xe4 [<ffffffff80096e91>] _local_bh_enable+0xcb/0xe0 [<ffffffff800606a8>] restore_args+0x0/0x30 [<ffffffff800270d2>] tcp_sendmsg+0x1c/0xb2f [<ffffffff80057540>] sock_sendmsg+0xf3/0x110 [<ffffffff800a2bb6>] autoremove_wake_function+0x0/0x2e [<ffffffff800a10e4>] kernel_text_address+0x1a/0x26 [<ffffffff8006f4e2>] dump_trace+0x211/0x23a [<ffffffff800a6d3d>] find_usage_backwards+0x5f/0x88 [<ffffffff8840221a>] :cifs:MD5Final+0xaf/0xc2 [<ffffffff884032ec>] :cifs:cifs_calculate_signature+0x55/0x69 [<ffffffff8021d891>] kernel_sendmsg+0x35/0x47 [<ffffffff883ff38e>] :cifs:smb_send+0xa3/0x151 [<ffffffff883ff5de>] :cifs:SendReceive+0x1a2/0x448 [<ffffffff800a812f>] __lock_acquire+0x95c/0xadf [<ffffffff883e758a>] :cifs:CIFSSMBSetEOF+0x20d/0x25b [<ffffffff883fa430>] :cifs:cifs_set_file_size+0x110/0x3b7 [<ffffffff883faa89>] :cifs:cifs_setattr+0x3b2/0x6f6 [<ffffffff8002e454>] notify_change+0xf5/0x2e0 [<ffffffff8002e4a4>] notify_change+0x145/0x2e0 [<ffffffff800e358d>] do_truncate+0x50/0x6b [<ffffffff8005197c>] get_write_access+0x40/0x46 [<ffffffff80012cf1>] may_open+0x1d3/0x22e [<ffffffff8001bc81>] open_namei+0x2c6/0x6dd [<ffffffff800289c6>] do_filp_open+0x1c/0x38 [<ffffffff800683ef>] _spin_unlock+0x17/0x20 [<ffffffff800167a7>] get_unused_fd+0xf9/0x107 [<ffffffff8001a704>] do_sys_open+0x44/0xbe [<ffffffff800602a6>] tracesys+0xd5/0xdf Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-07-23 22:11:19 +08:00
sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
&cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
}
#else
static inline void
cifs_reclassify_socket4(struct socket *sock)
{
}
static inline void
cifs_reclassify_socket6(struct socket *sock)
{
}
#endif
/* See RFC1001 section 14 on representation of Netbios names */
static void rfc1002mangle(char *target, char *source, unsigned int length)
{
unsigned int i, j;
for (i = 0, j = 0; i < (length); i++) {
/* mask a nibble at a time and encode */
target[j] = 'A' + (0x0F & (source[i] >> 4));
target[j+1] = 'A' + (0x0F & source[i]);
j += 2;
}
}
static int
bind_socket(struct TCP_Server_Info *server)
{
int rc = 0;
if (server->srcaddr.ss_family != AF_UNSPEC) {
/* Bind to the specified local IP address */
struct socket *socket = server->ssocket;
rc = socket->ops->bind(socket,
(struct sockaddr *) &server->srcaddr,
sizeof(server->srcaddr));
if (rc < 0) {
struct sockaddr_in *saddr4;
struct sockaddr_in6 *saddr6;
saddr4 = (struct sockaddr_in *)&server->srcaddr;
saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
if (saddr6->sin6_family == AF_INET6)
cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
&saddr6->sin6_addr, rc);
else
cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
&saddr4->sin_addr.s_addr, rc);
}
}
return rc;
}
static int
ip_rfc1001_connect(struct TCP_Server_Info *server)
{
int rc = 0;
/*
* some servers require RFC1001 sessinit before sending
* negprot - BB check reconnection in case where second
* sessinit is sent but no second negprot
*/
struct rfc1002_session_packet *ses_init_buf;
struct smb_hdr *smb_buf;
ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
GFP_KERNEL);
if (ses_init_buf) {
ses_init_buf->trailer.session_req.called_len = 32;
if (server->server_RFC1001_name[0] != 0)
rfc1002mangle(ses_init_buf->trailer.
session_req.called_name,
server->server_RFC1001_name,
RFC1001_NAME_LEN_WITH_NULL);
else
rfc1002mangle(ses_init_buf->trailer.
session_req.called_name,
DEFAULT_CIFS_CALLED_NAME,
RFC1001_NAME_LEN_WITH_NULL);
ses_init_buf->trailer.session_req.calling_len = 32;
/*
* calling name ends in null (byte 16) from old smb
* convention.
*/
if (server->workstation_RFC1001_name[0] != 0)
rfc1002mangle(ses_init_buf->trailer.
session_req.calling_name,
server->workstation_RFC1001_name,
RFC1001_NAME_LEN_WITH_NULL);
else
rfc1002mangle(ses_init_buf->trailer.
session_req.calling_name,
"LINUX_CIFS_CLNT",
RFC1001_NAME_LEN_WITH_NULL);
ses_init_buf->trailer.session_req.scope1 = 0;
ses_init_buf->trailer.session_req.scope2 = 0;
smb_buf = (struct smb_hdr *)ses_init_buf;
/* sizeof RFC1002_SESSION_REQUEST with no scope */
smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
rc = smb_send(server, smb_buf, 0x44);
kfree(ses_init_buf);
/*
* RFC1001 layer in at least one server
* requires very short break before negprot
* presumably because not expecting negprot
* to follow so fast. This is a simple
* solution that works without
* complicating the code and causes no
* significant slowing down on mount
* for everyone else
*/
usleep_range(1000, 2000);
}
/*
* else the negprot may still work without this
* even though malloc failed
*/
return rc;
}
static int
generic_ip_connect(struct TCP_Server_Info *server)
{
int rc = 0;
Elminate sparse __CHECK_ENDIAN__ warnings on port conversion Ports are __be16 not unsigned short int Eliminates the remaining fixable endian warnings: ~/cifs-2.6$ make modules C=1 M=fs/cifs CF=-D__CHECK_ENDIAN__ CHECK fs/cifs/connect.c fs/cifs/connect.c:2408:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2408:23: expected unsigned short *sport fs/cifs/connect.c:2408:23: got restricted __be16 *<noident> fs/cifs/connect.c:2410:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2410:23: expected unsigned short *sport fs/cifs/connect.c:2410:23: got restricted __be16 *<noident> fs/cifs/connect.c:2416:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2416:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2416:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2423:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2423:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2423:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2326:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2326:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2326:23: got restricted __be16 [usertype] sin6_port fs/cifs/connect.c:2330:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2330:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2330:23: got restricted __be16 [usertype] sin_port fs/cifs/connect.c:2394:22: warning: restricted __be16 degrades to integer Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-03-14 02:55:55 +08:00
__be16 sport;
int slen, sfamily;
struct socket *socket = server->ssocket;
struct sockaddr *saddr;
saddr = (struct sockaddr *) &server->dstaddr;
if (server->dstaddr.ss_family == AF_INET6) {
struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
sport = ipv6->sin6_port;
slen = sizeof(struct sockaddr_in6);
sfamily = AF_INET6;
cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
ntohs(sport));
} else {
struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
sport = ipv4->sin_port;
slen = sizeof(struct sockaddr_in);
sfamily = AF_INET;
cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
ntohs(sport));
}
if (socket == NULL) {
Make CIFS mount work in a container. Teach cifs about network namespaces, so mounting uses adresses/routing visible from the container rather than from init context. A container is a chroot on steroids that changes more than just the root filesystem the new processes see. One thing containers can isolate is "network namespaces", meaning each container can have its own set of ethernet interfaces, each with its own own IP address and routing to the outside world. And if you open a socket in _userspace_ from processes within such a container, this works fine. But sockets opened from within the kernel still use a single global networking context in a lot of places, meaning the new socket's address and routing are correct for PID 1 on the host, but are _not_ what userspace processes in the container get to use. So when you mount a network filesystem from within in a container, the mount code in the CIFS driver uses the host's networking context and not the container's networking context, so it gets the wrong address, uses the wrong routing, and may even try to go out an interface that the container can't even access... Bad stuff. This patch copies the mount process's network context into the CIFS structure that stores the rest of the server information for that mount point, and changes the socket open code to use the saved network context instead of the global network context. I.E. "when you attempt to use these addresses, do so relative to THIS set of network interfaces and routing rules, not the old global context from back before we supported containers". The big long HOWTO sets up a test environment on the assumption you've never used ocntainers before. It basically says: 1) configure and build a new kernel that has container support 2) build a new root filesystem that includes the userspace container control package (LXC) 3) package/run them under KVM (so you don't have to mess up your host system in order to play with containers). 4) set up some containers under the KVM system 5) set up contradictory routing in the KVM system and the container so that the host and the container see different things for the same address 6) try to mount a CIFS share from both contexts so you can both force it to work and force it to fail. For a long drawn out test reproduction sequence, see: http://landley.livejournal.com/47024.html http://landley.livejournal.com/47205.html http://landley.livejournal.com/47476.html Signed-off-by: Rob Landley <rlandley@parallels.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-01-23 05:44:05 +08:00
rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
IPPROTO_TCP, &socket, 1);
if (rc < 0) {
cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
server->ssocket = NULL;
return rc;
}
/* BB other socket options to set KEEPALIVE, NODELAY? */
cifs_dbg(FYI, "Socket created\n");
server->ssocket = socket;
socket->sk->sk_allocation = GFP_NOFS;
if (sfamily == AF_INET6)
cifs_reclassify_socket6(socket);
else
cifs_reclassify_socket4(socket);
}
rc = bind_socket(server);
if (rc < 0)
return rc;
/*
* Eventually check for other socket options to change from
* the default. sock_setsockopt not used because it expects
* user space buffer
*/
socket->sk->sk_rcvtimeo = 7 * HZ;
socket->sk->sk_sndtimeo = 5 * HZ;
/* make the bufsizes depend on wsize/rsize and max requests */
if (server->noautotune) {
if (socket->sk->sk_sndbuf < (200 * 1024))
socket->sk->sk_sndbuf = 200 * 1024;
if (socket->sk->sk_rcvbuf < (140 * 1024))
socket->sk->sk_rcvbuf = 140 * 1024;
}
if (server->tcp_nodelay)
tcp_sock_set_nodelay(socket->sk);
cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
socket->sk->sk_sndbuf,
socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
rc = socket->ops->connect(socket, saddr, slen,
server->noblockcnt ? O_NONBLOCK : 0);
/*
* When mounting SMB root file systems, we do not want to block in
* connect. Otherwise bail out and then let cifs_reconnect() perform
* reconnect failover - if possible.
*/
if (server->noblockcnt && rc == -EINPROGRESS)
rc = 0;
cifs: set socket send and receive timeouts before attempting connect Benjamin S. reported that he was unable to suspend his machine while it had a cifs share mounted. The freezer caused this to spew when he tried it: -----------------------[snip]------------------ PM: Syncing filesystems ... done. Freezing user space processes ... (elapsed 0.01 seconds) done. Freezing remaining freezable tasks ... Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0): cifsd S ffff880127f7b1b0 0 1821 2 0x00800000 ffff880127f7b1b0 0000000000000046 ffff88005fe008a8 ffff8800ffffffff ffff880127cee6b0 0000000000011100 ffff880127737fd8 0000000000004000 ffff880127737fd8 0000000000011100 ffff880127f7b1b0 ffff880127736010 Call Trace: [<ffffffff811e85dd>] ? sk_reset_timer+0xf/0x19 [<ffffffff8122cf3f>] ? tcp_connect+0x43c/0x445 [<ffffffff8123374e>] ? tcp_v4_connect+0x40d/0x47f [<ffffffff8126ce41>] ? schedule_timeout+0x21/0x1ad [<ffffffff8126e358>] ? _raw_spin_lock_bh+0x9/0x1f [<ffffffff811e81c7>] ? release_sock+0x19/0xef [<ffffffff8123e8be>] ? inet_stream_connect+0x14c/0x24a [<ffffffff8104485b>] ? autoremove_wake_function+0x0/0x2a [<ffffffffa02ccfe2>] ? ipv4_connect+0x39c/0x3b5 [cifs] [<ffffffffa02cd7b7>] ? cifs_reconnect+0x1fc/0x28a [cifs] [<ffffffffa02cdbdc>] ? cifs_demultiplex_thread+0x397/0xb9f [cifs] [<ffffffff81076afc>] ? perf_event_exit_task+0xb9/0x1bf [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs] [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs] [<ffffffff810444a1>] ? kthread+0x7a/0x82 [<ffffffff81002d14>] ? kernel_thread_helper+0x4/0x10 [<ffffffff81044427>] ? kthread+0x0/0x82 [<ffffffff81002d10>] ? kernel_thread_helper+0x0/0x10 Restarting tasks ... done. -----------------------[snip]------------------ We do attempt to perform a try_to_freeze in cifs_reconnect, but the connection attempt itself seems to be taking longer than 20s to time out. The connect timeout is governed by the socket send and receive timeouts, so we can shorten that period by setting those timeouts before attempting the connect instead of after. Adam Williamson tested the patch and said that it seems to have fixed suspending on his laptop when a cifs share is mounted. Reported-by: Benjamin S <da_joind@gmx.net> Tested-by: Adam Williamson <awilliam@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-21 19:18:26 +08:00
if (rc < 0) {
cifs_dbg(FYI, "Error %d connecting to server\n", rc);
smb3: add dynamic trace points for socket connection In debugging user problems with ip address/DNS issues with smb3 mounts, we sometimes needed additional info on the hostname and ip address. Add two tracepoints, one to show socket connection success and one for failures to connect to the socket. Sample output: mount.cifs-14551 [005] ..... 7636.547906: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445 mount.cifs-14558 [004] ..... 7642.405413: smb3_connect_done: conn_id=0x2 server=smfrench.file.core.windows.net addr=52.239.158.232:445 mount.cifs-14741 [005] ..... 7818.490716: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0 mount.cifs-14810 [000] ..... 7966.380337: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:445/0%0 mount.cifs-14810 [000] ..... 7966.380356: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:139/0%0 mount.cifs-14818 [003] ..... 7986.771992: smb3_connect_done: conn_id=0x5 server=127.0.0.9 addr=127.0.0.9:445 mount.cifs-14825 [008] ..... 8008.178109: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:445 mount.cifs-14825 [008] ..... 8013.298085: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:139 cifsd-14553 [006] ..... 8036.735615: smb3_reconnect: conn_id=0x1 server=localhost current_mid=32 cifsd-14743 [010] ..... 8036.735644: smb3_reconnect: conn_id=0x3 server=::1 current_mid=29 cifsd-14743 [010] ..... 8039.921740: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8042.993894: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8042.993894: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8046.065824: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8046.065824: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8049.137796: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8049.137796: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0 Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 04:56:37 +08:00
trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
cifs: set socket send and receive timeouts before attempting connect Benjamin S. reported that he was unable to suspend his machine while it had a cifs share mounted. The freezer caused this to spew when he tried it: -----------------------[snip]------------------ PM: Syncing filesystems ... done. Freezing user space processes ... (elapsed 0.01 seconds) done. Freezing remaining freezable tasks ... Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0): cifsd S ffff880127f7b1b0 0 1821 2 0x00800000 ffff880127f7b1b0 0000000000000046 ffff88005fe008a8 ffff8800ffffffff ffff880127cee6b0 0000000000011100 ffff880127737fd8 0000000000004000 ffff880127737fd8 0000000000011100 ffff880127f7b1b0 ffff880127736010 Call Trace: [<ffffffff811e85dd>] ? sk_reset_timer+0xf/0x19 [<ffffffff8122cf3f>] ? tcp_connect+0x43c/0x445 [<ffffffff8123374e>] ? tcp_v4_connect+0x40d/0x47f [<ffffffff8126ce41>] ? schedule_timeout+0x21/0x1ad [<ffffffff8126e358>] ? _raw_spin_lock_bh+0x9/0x1f [<ffffffff811e81c7>] ? release_sock+0x19/0xef [<ffffffff8123e8be>] ? inet_stream_connect+0x14c/0x24a [<ffffffff8104485b>] ? autoremove_wake_function+0x0/0x2a [<ffffffffa02ccfe2>] ? ipv4_connect+0x39c/0x3b5 [cifs] [<ffffffffa02cd7b7>] ? cifs_reconnect+0x1fc/0x28a [cifs] [<ffffffffa02cdbdc>] ? cifs_demultiplex_thread+0x397/0xb9f [cifs] [<ffffffff81076afc>] ? perf_event_exit_task+0xb9/0x1bf [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs] [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs] [<ffffffff810444a1>] ? kthread+0x7a/0x82 [<ffffffff81002d14>] ? kernel_thread_helper+0x4/0x10 [<ffffffff81044427>] ? kthread+0x0/0x82 [<ffffffff81002d10>] ? kernel_thread_helper+0x0/0x10 Restarting tasks ... done. -----------------------[snip]------------------ We do attempt to perform a try_to_freeze in cifs_reconnect, but the connection attempt itself seems to be taking longer than 20s to time out. The connect timeout is governed by the socket send and receive timeouts, so we can shorten that period by setting those timeouts before attempting the connect instead of after. Adam Williamson tested the patch and said that it seems to have fixed suspending on his laptop when a cifs share is mounted. Reported-by: Benjamin S <da_joind@gmx.net> Tested-by: Adam Williamson <awilliam@redhat.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-21 19:18:26 +08:00
sock_release(socket);
server->ssocket = NULL;
return rc;
}
smb3: add dynamic trace points for socket connection In debugging user problems with ip address/DNS issues with smb3 mounts, we sometimes needed additional info on the hostname and ip address. Add two tracepoints, one to show socket connection success and one for failures to connect to the socket. Sample output: mount.cifs-14551 [005] ..... 7636.547906: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445 mount.cifs-14558 [004] ..... 7642.405413: smb3_connect_done: conn_id=0x2 server=smfrench.file.core.windows.net addr=52.239.158.232:445 mount.cifs-14741 [005] ..... 7818.490716: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0 mount.cifs-14810 [000] ..... 7966.380337: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:445/0%0 mount.cifs-14810 [000] ..... 7966.380356: smb3_connect_err: rc=-101 conn_id=0x4 server=::2 addr=[::2]:139/0%0 mount.cifs-14818 [003] ..... 7986.771992: smb3_connect_done: conn_id=0x5 server=127.0.0.9 addr=127.0.0.9:445 mount.cifs-14825 [008] ..... 8008.178109: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:445 mount.cifs-14825 [008] ..... 8013.298085: smb3_connect_err: rc=-115 conn_id=0x6 server=124.23.0.9 addr=124.23.0.9:139 cifsd-14553 [006] ..... 8036.735615: smb3_reconnect: conn_id=0x1 server=localhost current_mid=32 cifsd-14743 [010] ..... 8036.735644: smb3_reconnect: conn_id=0x3 server=::1 current_mid=29 cifsd-14743 [010] ..... 8039.921740: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8042.993894: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8042.993894: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8046.065824: smb3_connect_err: rc=-111 conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8046.065824: smb3_connect_err: rc=-111 conn_id=0x3 server=::1 addr=[::1]:445/0%0 cifsd-14553 [008] ..... 8049.137796: smb3_connect_done: conn_id=0x1 server=localhost addr=127.0.0.1:445 cifsd-14743 [010] ..... 8049.137796: smb3_connect_done: conn_id=0x3 server=::1 addr=[::1]:445/0%0 Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 04:56:37 +08:00
trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
if (sport == htons(RFC1001_PORT))
rc = ip_rfc1001_connect(server);
return rc;
}
static int
ip_connect(struct TCP_Server_Info *server)
{
Elminate sparse __CHECK_ENDIAN__ warnings on port conversion Ports are __be16 not unsigned short int Eliminates the remaining fixable endian warnings: ~/cifs-2.6$ make modules C=1 M=fs/cifs CF=-D__CHECK_ENDIAN__ CHECK fs/cifs/connect.c fs/cifs/connect.c:2408:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2408:23: expected unsigned short *sport fs/cifs/connect.c:2408:23: got restricted __be16 *<noident> fs/cifs/connect.c:2410:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2410:23: expected unsigned short *sport fs/cifs/connect.c:2410:23: got restricted __be16 *<noident> fs/cifs/connect.c:2416:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2416:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2416:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2423:24: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2423:24: expected unsigned short [unsigned] [short] <noident> fs/cifs/connect.c:2423:24: got restricted __be16 [usertype] <noident> fs/cifs/connect.c:2326:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2326:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2326:23: got restricted __be16 [usertype] sin6_port fs/cifs/connect.c:2330:23: warning: incorrect type in assignment (different base types) fs/cifs/connect.c:2330:23: expected unsigned short [unsigned] sport fs/cifs/connect.c:2330:23: got restricted __be16 [usertype] sin_port fs/cifs/connect.c:2394:22: warning: restricted __be16 degrades to integer Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-03-14 02:55:55 +08:00
__be16 *sport;
struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
if (server->dstaddr.ss_family == AF_INET6)
sport = &addr6->sin6_port;
else
sport = &addr->sin_port;
if (*sport == 0) {
int rc;
/* try with 445 port at first */
*sport = htons(CIFS_PORT);
rc = generic_ip_connect(server);
if (rc >= 0)
return rc;
/* if it failed, try with 139 port */
*sport = htons(RFC1001_PORT);
}
return generic_ip_connect(server);
}
void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
{
/*
* If we are reconnecting then should we check to see if
* any requested capabilities changed locally e.g. via
* remount but we can not do much about it here
* if they have (even if we could detect it by the following)
* Perhaps we could add a backpointer to array of sb from tcon
* or if we change to make all sb to same share the same
* sb as NFS - then we only have one backpointer to sb.
* What if we wanted to mount the server share twice once with
* and once without posixacls or posix paths?
*/
__u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
if (ctx && ctx->no_linux_ext) {
tcon->fsUnixInfo.Capability = 0;
tcon->unix_ext = 0; /* Unix Extensions disabled */
cifs_dbg(FYI, "Linux protocol extensions disabled\n");
return;
} else if (ctx)
tcon->unix_ext = 1; /* Unix Extensions supported */
if (!tcon->unix_ext) {
cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
return;
}
if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
__u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
/*
* check for reconnect case in which we do not
* want to change the mount behavior if we can avoid it
*/
if (ctx == NULL) {
/*
* turn off POSIX ACL and PATHNAMES if not set
* originally at mount time
*/
if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
cifs_dbg(VFS, "POSIXPATH support change\n");
cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
} else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
cifs_dbg(VFS, "possible reconnect error\n");
cifs_dbg(VFS, "server disabled POSIX path support\n");
}
}
if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
cifs_dbg(VFS, "per-share encryption not supported yet\n");
cap &= CIFS_UNIX_CAP_MASK;
if (ctx && ctx->no_psx_acl)
cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
cifs_dbg(FYI, "negotiated posix acl support\n");
if (cifs_sb)
cifs_sb->mnt_cifs_flags |=
CIFS_MOUNT_POSIXACL;
}
if (ctx && ctx->posix_paths == 0)
cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
cifs_dbg(FYI, "negotiate posix pathnames\n");
if (cifs_sb)
cifs_sb->mnt_cifs_flags |=
CIFS_MOUNT_POSIX_PATHS;
}
cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
#ifdef CONFIG_CIFS_DEBUG2
if (cap & CIFS_UNIX_FCNTL_CAP)
cifs_dbg(FYI, "FCNTL cap\n");
if (cap & CIFS_UNIX_EXTATTR_CAP)
cifs_dbg(FYI, "EXTATTR cap\n");
if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
cifs_dbg(FYI, "POSIX path cap\n");
if (cap & CIFS_UNIX_XATTR_CAP)
cifs_dbg(FYI, "XATTR cap\n");
if (cap & CIFS_UNIX_POSIX_ACL_CAP)
cifs_dbg(FYI, "POSIX ACL cap\n");
if (cap & CIFS_UNIX_LARGE_READ_CAP)
cifs_dbg(FYI, "very large read cap\n");
if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
cifs_dbg(FYI, "very large write cap\n");
if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
cifs_dbg(FYI, "transport encryption cap\n");
if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
cifs_dbg(FYI, "mandatory transport encryption cap\n");
#endif /* CIFS_DEBUG2 */
if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
if (ctx == NULL)
cifs_dbg(FYI, "resetting capabilities failed\n");
else
cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
}
}
}
int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
{
struct smb3_fs_context *ctx = cifs_sb->ctx;
INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
spin_lock_init(&cifs_sb->tlink_tree_lock);
cifs_sb->tlink_tree = RB_ROOT;
cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n",
ctx->file_mode, ctx->dir_mode);
/* this is needed for ASCII cp to Unicode converts */
if (ctx->iocharset == NULL) {
/* load_nls_default cannot return null */
cifs_sb->local_nls = load_nls_default();
} else {
cifs_sb->local_nls = load_nls(ctx->iocharset);
if (cifs_sb->local_nls == NULL) {
cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
ctx->iocharset);
return -ELIBACC;
}
}
ctx->local_nls = cifs_sb->local_nls;
smb3_update_mnt_flags(cifs_sb);
if (ctx->direct_io)
cifs_dbg(FYI, "mounting share using direct i/o\n");
if (ctx->cache_ro) {
cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
} else if (ctx->cache_rw) {
cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
CIFS_MOUNT_RW_CACHE);
}
if ((ctx->cifs_acl) && (ctx->dynperm))
cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
if (ctx->prepath) {
cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
if (cifs_sb->prepath == NULL)
return -ENOMEM;
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
}
return 0;
}
/* Release all succeed connections */
static inline void mount_put_conns(struct mount_ctx *mnt_ctx)
{
int rc = 0;
if (mnt_ctx->tcon)
cifs_put_tcon(mnt_ctx->tcon);
else if (mnt_ctx->ses)
cifs_put_smb_ses(mnt_ctx->ses);
else if (mnt_ctx->server)
cifs_put_tcp_session(mnt_ctx->server, 0);
mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
free_xid(mnt_ctx->xid);
}
/* Get connections for tcp, ses and tcon */
static int mount_get_conns(struct mount_ctx *mnt_ctx)
{
int rc = 0;
struct TCP_Server_Info *server = NULL;
struct cifs_ses *ses = NULL;
struct cifs_tcon *tcon = NULL;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
unsigned int xid;
xid = get_xid();
/* get a reference to a tcp session */
server = cifs_get_tcp_session(ctx);
if (IS_ERR(server)) {
rc = PTR_ERR(server);
server = NULL;
goto out;
}
/* get a reference to a SMB session */
ses = cifs_get_smb_ses(server, ctx);
if (IS_ERR(ses)) {
rc = PTR_ERR(ses);
ses = NULL;
goto out;
}
if ((ctx->persistent == true) && (!(ses->server->capabilities &
SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
cifs_server_dbg(VFS, "persistent handles not supported by server\n");
rc = -EOPNOTSUPP;
goto out;
}
/* search for existing tcon to this server share */
tcon = cifs_get_tcon(ses, ctx);
if (IS_ERR(tcon)) {
rc = PTR_ERR(tcon);
tcon = NULL;
goto out;
}
/* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
if (tcon->posix_extensions)
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
/* tell server which Unix caps we support */
if (cap_unix(tcon->ses)) {
/*
* reset of caps checks mount to see if unix extensions disabled
* for just this mount.
*/
reset_cifs_unix_caps(xid, tcon, cifs_sb, ctx);
if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
(le64_to_cpu(tcon->fsUnixInfo.Capability) &
CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
rc = -EACCES;
goto out;
}
} else
tcon->unix_ext = 0; /* server does not support them */
/* do not care if a following call succeed - informational */
if (!tcon->pipe && server->ops->qfs_tcon) {
server->ops->qfs_tcon(xid, tcon, cifs_sb);
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
if (tcon->fsDevInfo.DeviceCharacteristics &
cpu_to_le32(FILE_READ_ONLY_DEVICE))
cifs_dbg(VFS, "mounted to read only share\n");
else if ((cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_RW_CACHE) == 0)
cifs_dbg(VFS, "read only mount of RW share\n");
/* no need to log a RW mount of a typical RW share */
}
/*
* The cookie is initialized from volume info returned above.
* Inside cifs_fscache_get_super_cookie it checks
* that we do not get super cookie twice.
*/
cifs_fscache_get_super_cookie(tcon);
}
/*
* Clamp the rsize/wsize mount arguments if they are too big for the server
* and set the rsize/wsize to the negotiated values if not passed in by
* the user on mount
*/
if ((cifs_sb->ctx->wsize == 0) ||
(cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
if ((cifs_sb->ctx->rsize == 0) ||
(cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
out:
mnt_ctx->server = server;
mnt_ctx->ses = ses;
mnt_ctx->tcon = tcon;
mnt_ctx->xid = xid;
return rc;
}
static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
struct cifs_tcon *tcon)
{
struct tcon_link *tlink;
/* hang the tcon off of the superblock */
tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
if (tlink == NULL)
return -ENOMEM;
tlink->tl_uid = ses->linux_uid;
tlink->tl_tcon = tcon;
tlink->tl_time = jiffies;
set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
cifs_sb->master_tlink = tlink;
spin_lock(&cifs_sb->tlink_tree_lock);
tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
spin_unlock(&cifs_sb->tlink_tree_lock);
queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
TLINK_IDLE_EXPIRE);
return 0;
}
#ifdef CONFIG_CIFS_DFS_UPCALL
/* Get unique dfs connections */
static int mount_get_dfs_conns(struct mount_ctx *mnt_ctx)
{
int rc;
mnt_ctx->fs_ctx->nosharesock = true;
rc = mount_get_conns(mnt_ctx);
if (mnt_ctx->server) {
cifs_dbg(FYI, "%s: marking tcp session as a dfs connection\n", __func__);
spin_lock(&cifs_tcp_ses_lock);
mnt_ctx->server->is_dfs_conn = true;
spin_unlock(&cifs_tcp_ses_lock);
}
return rc;
}
/*
* cifs_build_path_to_root returns full path to root when we do not have an
* existing connection (tcon)
*/
static char *
build_unc_path_to_root(const struct smb3_fs_context *ctx,
const struct cifs_sb_info *cifs_sb, bool useppath)
{
char *full_path, *pos;
unsigned int pplen = useppath && ctx->prepath ?
strlen(ctx->prepath) + 1 : 0;
unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1);
if (unc_len > MAX_TREE_SIZE)
return ERR_PTR(-EINVAL);
full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
if (full_path == NULL)
return ERR_PTR(-ENOMEM);
memcpy(full_path, ctx->UNC, unc_len);
pos = full_path + unc_len;
if (pplen) {
*pos = CIFS_DIR_SEP(cifs_sb);
memcpy(pos + 1, ctx->prepath, pplen);
pos += pplen;
}
*pos = '\0'; /* add trailing null */
convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
return full_path;
}
/*
* expand_dfs_referral - Update cifs_sb from dfs referral path
*
* cifs_sb->ctx->mount_options will be (re-)allocated to a string containing updated options for the
* submount. Otherwise it will be left untouched.
*/
static int expand_dfs_referral(struct mount_ctx *mnt_ctx, const char *full_path,
struct dfs_info3_param *referral)
{
int rc;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
char *fake_devname = NULL, *mdata = NULL;
mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options, full_path + 1, referral,
&fake_devname);
if (IS_ERR(mdata)) {
rc = PTR_ERR(mdata);
mdata = NULL;
} else {
/*
* We can not clear out the whole structure since we no longer have an explicit
* function to parse a mount-string. Instead we need to clear out the individual
* fields that are no longer valid.
*/
kfree(ctx->prepath);
ctx->prepath = NULL;
rc = cifs_setup_volume_info(ctx, mdata, fake_devname);
}
kfree(fake_devname);
kfree(cifs_sb->ctx->mount_options);
cifs_sb->ctx->mount_options = mdata;
return rc;
}
#endif
/* TODO: all callers to this are broken. We are not parsing mount_options here
* we should pass a clone of the original context?
*/
int
cifs_setup_volume_info(struct smb3_fs_context *ctx, const char *mntopts, const char *devname)
{
int rc;
if (devname) {
cifs_dbg(FYI, "%s: devname=%s\n", __func__, devname);
rc = smb3_parse_devname(devname, ctx);
if (rc) {
cifs_dbg(VFS, "%s: failed to parse %s: %d\n", __func__, devname, rc);
return rc;
}
}
if (mntopts) {
char *ip;
rc = smb3_parse_opt(mntopts, "ip", &ip);
if (rc) {
cifs_dbg(VFS, "%s: failed to parse ip options: %d\n", __func__, rc);
return rc;
}
rc = cifs_convert_address((struct sockaddr *)&ctx->dstaddr, ip, strlen(ip));
kfree(ip);
if (!rc) {
cifs_dbg(VFS, "%s: failed to convert ip address\n", __func__);
return -EINVAL;
}
}
if (ctx->nullauth) {
cifs_dbg(FYI, "Anonymous login\n");
kfree(ctx->username);
ctx->username = NULL;
} else if (ctx->username) {
/* BB fixme parse for domain name here */
cifs_dbg(FYI, "Username: %s\n", ctx->username);
} else {
cifs_dbg(VFS, "No username specified\n");
/* In userspace mount helper we can get user name from alternate
locations such as env variables and files on disk */
return -EINVAL;
}
return 0;
}
static int
cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
unsigned int xid,
struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb,
char *full_path,
int added_treename)
{
int rc;
char *s;
char sep, tmp;
int skip = added_treename ? 1 : 0;
sep = CIFS_DIR_SEP(cifs_sb);
s = full_path;
rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
while (rc == 0) {
/* skip separators */
while (*s == sep)
s++;
if (!*s)
break;
/* next separator */
while (*s && *s != sep)
s++;
/*
* if the treename is added, we then have to skip the first
* part within the separators
*/
if (skip) {
skip = 0;
continue;
}
/*
* temporarily null-terminate the path at the end of
* the current component
*/
tmp = *s;
*s = 0;
rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
full_path);
*s = tmp;
}
return rc;
}
/*
* Check if path is remote (e.g. a DFS share). Return -EREMOTE if it is,
* otherwise 0.
*/
static int is_path_remote(struct mount_ctx *mnt_ctx)
{
int rc;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct TCP_Server_Info *server = mnt_ctx->server;
unsigned int xid = mnt_ctx->xid;
struct cifs_tcon *tcon = mnt_ctx->tcon;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
char *full_path;
if (!server->ops->is_path_accessible)
return -EOPNOTSUPP;
/*
* cifs_build_path_to_root works only when we have a valid tcon
*/
full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
tcon->Flags & SMB_SHARE_IS_IN_DFS);
if (full_path == NULL)
return -ENOMEM;
cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
full_path);
if (rc != 0 && rc != -EREMOTE) {
kfree(full_path);
return rc;
}
if (rc != -EREMOTE) {
rc = cifs_are_all_path_components_accessible(server, xid, tcon,
cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
if (rc != 0) {
cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
rc = 0;
}
}
kfree(full_path);
return rc;
}
#ifdef CONFIG_CIFS_DFS_UPCALL
static void set_root_ses(struct mount_ctx *mnt_ctx)
{
if (mnt_ctx->ses) {
spin_lock(&cifs_tcp_ses_lock);
mnt_ctx->ses->ses_count++;
spin_unlock(&cifs_tcp_ses_lock);
dfs_cache_add_refsrv_session(&mnt_ctx->mount_id, mnt_ctx->ses);
}
mnt_ctx->root_ses = mnt_ctx->ses;
}
static int is_dfs_mount(struct mount_ctx *mnt_ctx, bool *isdfs, struct dfs_cache_tgt_list *root_tl)
{
int rc;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
*isdfs = true;
rc = mount_get_conns(mnt_ctx);
/*
* If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally
* try to get an DFS referral (even cached) to determine whether it is an DFS mount.
*
* Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
* to respond with PATH_NOT_COVERED to requests that include the prefix.
*/
if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||
dfs_cache_find(mnt_ctx->xid, mnt_ctx->ses, cifs_sb->local_nls, cifs_remap(cifs_sb),
ctx->UNC + 1, NULL, root_tl)) {
if (rc)
return rc;
/* Check if it is fully accessible and then mount it */
rc = is_path_remote(mnt_ctx);
if (!rc)
*isdfs = false;
else if (rc != -EREMOTE)
return rc;
}
return 0;
}
static int connect_dfs_target(struct mount_ctx *mnt_ctx, const char *full_path,
const char *ref_path, struct dfs_cache_tgt_iterator *tit)
{
int rc;
struct dfs_info3_param ref = {};
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
char *oldmnt = cifs_sb->ctx->mount_options;
rc = dfs_cache_get_tgt_referral(ref_path, tit, &ref);
if (rc)
goto out;
rc = expand_dfs_referral(mnt_ctx, full_path, &ref);
if (rc)
goto out;
/* Connect to new target only if we were redirected (e.g. mount options changed) */
if (oldmnt != cifs_sb->ctx->mount_options) {
mount_put_conns(mnt_ctx);
rc = mount_get_dfs_conns(mnt_ctx);
}
if (!rc) {
if (cifs_is_referral_server(mnt_ctx->tcon, &ref))
set_root_ses(mnt_ctx);
rc = dfs_cache_update_tgthint(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,
cifs_remap(cifs_sb), ref_path, tit);
}
out:
free_dfs_info_param(&ref);
return rc;
}
static int connect_dfs_root(struct mount_ctx *mnt_ctx, struct dfs_cache_tgt_list *root_tl)
{
int rc;
char *full_path;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
struct dfs_cache_tgt_iterator *tit;
/* Put initial connections as they might be shared with other mounts. We need unique dfs
* connections per mount to properly failover, so mount_get_dfs_conns() must be used from
* now on.
*/
mount_put_conns(mnt_ctx);
mount_get_dfs_conns(mnt_ctx);
full_path = build_unc_path_to_root(ctx, cifs_sb, true);
if (IS_ERR(full_path))
return PTR_ERR(full_path);
mnt_ctx->origin_fullpath = dfs_cache_canonical_path(ctx->UNC, cifs_sb->local_nls,
cifs_remap(cifs_sb));
if (IS_ERR(mnt_ctx->origin_fullpath)) {
rc = PTR_ERR(mnt_ctx->origin_fullpath);
mnt_ctx->origin_fullpath = NULL;
goto out;
}
/* Try all dfs root targets */
for (rc = -ENOENT, tit = dfs_cache_get_tgt_iterator(root_tl);
tit; tit = dfs_cache_get_next_tgt(root_tl, tit)) {
rc = connect_dfs_target(mnt_ctx, full_path, mnt_ctx->origin_fullpath + 1, tit);
if (!rc) {
mnt_ctx->leaf_fullpath = kstrdup(mnt_ctx->origin_fullpath, GFP_KERNEL);
if (!mnt_ctx->leaf_fullpath)
rc = -ENOMEM;
break;
}
}
out:
kfree(full_path);
return rc;
}
static int __follow_dfs_link(struct mount_ctx *mnt_ctx)
{
int rc;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
char *full_path;
struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
struct dfs_cache_tgt_iterator *tit;
full_path = build_unc_path_to_root(ctx, cifs_sb, true);
if (IS_ERR(full_path))
return PTR_ERR(full_path);
kfree(mnt_ctx->leaf_fullpath);
mnt_ctx->leaf_fullpath = dfs_cache_canonical_path(full_path, cifs_sb->local_nls,
cifs_remap(cifs_sb));
if (IS_ERR(mnt_ctx->leaf_fullpath)) {
rc = PTR_ERR(mnt_ctx->leaf_fullpath);
mnt_ctx->leaf_fullpath = NULL;
goto out;
}
/* Get referral from dfs link */
rc = dfs_cache_find(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,
cifs_remap(cifs_sb), mnt_ctx->leaf_fullpath + 1, NULL, &tl);
if (rc)
goto out;
/* Try all dfs link targets */
for (rc = -ENOENT, tit = dfs_cache_get_tgt_iterator(&tl);
tit; tit = dfs_cache_get_next_tgt(&tl, tit)) {
rc = connect_dfs_target(mnt_ctx, full_path, mnt_ctx->leaf_fullpath + 1, tit);
if (!rc) {
rc = is_path_remote(mnt_ctx);
break;
}
}
out:
kfree(full_path);
dfs_cache_free_tgts(&tl);
return rc;
}
static int follow_dfs_link(struct mount_ctx *mnt_ctx)
{
int rc;
struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
char *full_path;
int num_links = 0;
full_path = build_unc_path_to_root(ctx, cifs_sb, true);
if (IS_ERR(full_path))
return PTR_ERR(full_path);
kfree(mnt_ctx->origin_fullpath);
mnt_ctx->origin_fullpath = dfs_cache_canonical_path(full_path, cifs_sb->local_nls,
cifs_remap(cifs_sb));
kfree(full_path);
if (IS_ERR(mnt_ctx->origin_fullpath)) {
rc = PTR_ERR(mnt_ctx->origin_fullpath);
mnt_ctx->origin_fullpath = NULL;
return rc;
}
do {
rc = __follow_dfs_link(mnt_ctx);
if (!rc || rc != -EREMOTE)
break;
} while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS);
return rc;
}
/* Set up DFS referral paths for failover */
static void setup_server_referral_paths(struct mount_ctx *mnt_ctx)
{
struct TCP_Server_Info *server = mnt_ctx->server;
server->origin_fullpath = mnt_ctx->origin_fullpath;
server->leaf_fullpath = mnt_ctx->leaf_fullpath;
server->current_fullpath = mnt_ctx->leaf_fullpath;
mnt_ctx->origin_fullpath = mnt_ctx->leaf_fullpath = NULL;
}
int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
{
int rc;
struct mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
bool isdfs;
rc = is_dfs_mount(&mnt_ctx, &isdfs, &tl);
if (rc)
goto error;
if (!isdfs)
goto out;
uuid_gen(&mnt_ctx.mount_id);
rc = connect_dfs_root(&mnt_ctx, &tl);
dfs_cache_free_tgts(&tl);
if (rc)
goto error;
rc = is_path_remote(&mnt_ctx);
if (rc == -EREMOTE)
rc = follow_dfs_link(&mnt_ctx);
if (rc)
goto error;
setup_server_referral_paths(&mnt_ctx);
/*
* After reconnecting to a different server, unique ids won't match anymore, so we disable
* serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
*/
cifs_autodisable_serverino(cifs_sb);
/*
* Force the use of prefix path to support failover on DFS paths that resolve to targets
* that have different prefix paths.
*/
cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
kfree(cifs_sb->prepath);
cifs_sb->prepath = ctx->prepath;
ctx->prepath = NULL;
uuid_copy(&cifs_sb->dfs_mount_id, &mnt_ctx.mount_id);
out:
free_xid(mnt_ctx.xid);
cifs_try_adding_channels(cifs_sb, mnt_ctx.ses);
return mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
error:
dfs_cache_put_refsrv_sessions(&mnt_ctx.mount_id);
kfree(mnt_ctx.origin_fullpath);
kfree(mnt_ctx.leaf_fullpath);
mount_put_conns(&mnt_ctx);
return rc;
}
#else
int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
{
int rc = 0;
struct mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
rc = mount_get_conns(&mnt_ctx);
if (rc)
goto error;
if (mnt_ctx.tcon) {
rc = is_path_remote(&mnt_ctx);
if (rc == -EREMOTE)
rc = -EOPNOTSUPP;
if (rc)
goto error;
}
free_xid(mnt_ctx.xid);
return mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
error:
mount_put_conns(&mnt_ctx);
return rc;
}
#endif
/*
* Issue a TREE_CONNECT request.
*/
int
CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
const char *tree, struct cifs_tcon *tcon,
const struct nls_table *nls_codepage)
{
struct smb_hdr *smb_buffer;
struct smb_hdr *smb_buffer_response;
TCONX_REQ *pSMB;
TCONX_RSP *pSMBr;
unsigned char *bcc_ptr;
int rc = 0;
int length;
__u16 bytes_left, count;
if (ses == NULL)
return -EIO;
smb_buffer = cifs_buf_get();
if (smb_buffer == NULL)
return -ENOMEM;
smb_buffer_response = smb_buffer;
header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
NULL /*no tid */ , 4 /*wct */ );
smb_buffer->Mid = get_next_mid(ses->server);
smb_buffer->Uid = ses->Suid;
pSMB = (TCONX_REQ *) smb_buffer;
pSMBr = (TCONX_RSP *) smb_buffer_response;
pSMB->AndXCommand = 0xFF;
pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
bcc_ptr = &pSMB->Password[0];
if (tcon->pipe || (ses->server->sec_mode & SECMODE_USER)) {
pSMB->PasswordLength = cpu_to_le16(1); /* minimum */
*bcc_ptr = 0; /* password is null byte */
bcc_ptr++; /* skip password */
/* already aligned so no need to do it below */
}
if (ses->server->sign)
smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
if (ses->capabilities & CAP_STATUS32) {
smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
}
if (ses->capabilities & CAP_DFS) {
smb_buffer->Flags2 |= SMBFLG2_DFS;
}
if (ses->capabilities & CAP_UNICODE) {
smb_buffer->Flags2 |= SMBFLG2_UNICODE;
length =
cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
6 /* max utf8 char length in bytes */ *
(/* server len*/ + 256 /* share len */), nls_codepage);
bcc_ptr += 2 * length; /* convert num 16 bit words to bytes */
bcc_ptr += 2; /* skip trailing null */
} else { /* ASCII */
strcpy(bcc_ptr, tree);
bcc_ptr += strlen(tree) + 1;
}
strcpy(bcc_ptr, "?????");
bcc_ptr += strlen("?????");
bcc_ptr += 1;
count = bcc_ptr - &pSMB->Password[0];
be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
pSMB->ByteCount = cpu_to_le16(count);
rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
0);
/* above now done in SendReceive */
if (rc == 0) {
bool is_unicode;
tcon->tidStatus = CifsGood;
tcon->need_reconnect = false;
tcon->tid = smb_buffer_response->Tid;
bcc_ptr = pByteArea(smb_buffer_response);
bytes_left = get_bcc(smb_buffer_response);
length = strnlen(bcc_ptr, bytes_left - 2);
if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
is_unicode = true;
else
is_unicode = false;
/* skip service field (NB: this field is always ASCII) */
if (length == 3) {
if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
(bcc_ptr[2] == 'C')) {
cifs_dbg(FYI, "IPC connection\n");
tcon->ipc = true;
tcon->pipe = true;
}
} else if (length == 2) {
if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
/* the most common case */
cifs_dbg(FYI, "disk share connection\n");
}
}
bcc_ptr += length + 1;
bytes_left -= (length + 1);
strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
/* mostly informational -- no need to fail on error here */
kfree(tcon->nativeFileSystem);
tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
bytes_left, is_unicode,
nls_codepage);
cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
if ((smb_buffer_response->WordCount == 3) ||
(smb_buffer_response->WordCount == 7))
/* field is in same location */
tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
else
tcon->Flags = 0;
cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
}
cifs_buf_release(smb_buffer);
return rc;
}
static void delayed_free(struct rcu_head *p)
{
struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
unload_nls(cifs_sb->local_nls);
smb3_cleanup_fs_context(cifs_sb->ctx);
kfree(cifs_sb);
}
void
cifs_umount(struct cifs_sb_info *cifs_sb)
{
struct rb_root *root = &cifs_sb->tlink_tree;
struct rb_node *node;
struct tcon_link *tlink;
cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
spin_lock(&cifs_sb->tlink_tree_lock);
while ((node = rb_first(root))) {
tlink = rb_entry(node, struct tcon_link, tl_rbnode);
cifs_get_tlink(tlink);
clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
rb_erase(node, root);
spin_unlock(&cifs_sb->tlink_tree_lock);
cifs_put_tlink(tlink);
spin_lock(&cifs_sb->tlink_tree_lock);
}
spin_unlock(&cifs_sb->tlink_tree_lock);
kfree(cifs_sb->prepath);
#ifdef CONFIG_CIFS_DFS_UPCALL
dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
#endif
call_rcu(&cifs_sb->rcu, delayed_free);
}
int
cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
{
int rc = 0;
struct TCP_Server_Info *server = cifs_ses_server(ses);
if (!server->ops->need_neg || !server->ops->negotiate)
return -ENOSYS;
/* only send once per connect */
if (!server->ops->need_neg(server))
return 0;
rc = server->ops->negotiate(xid, ses);
if (rc == 0) {
spin_lock(&GlobalMid_Lock);
cifs: don't allow cifs_reconnect to exit with NULL socket pointer It's possible for the following set of events to happen: cifsd calls cifs_reconnect which reconnects the socket. A userspace process then calls cifs_negotiate_protocol to handle the NEGOTIATE and gets a reply. But, while processing the reply, cifsd calls cifs_reconnect again. Eventually the GlobalMid_Lock is dropped and the reply from the earlier NEGOTIATE completes and the tcpStatus is set to CifsGood. cifs_reconnect then goes through and closes the socket and sets the pointer to zero, but because the status is now CifsGood, the new socket is not created and cifs_reconnect exits with the socket pointer set to NULL. Fix this by only setting the tcpStatus to CifsGood if the tcpStatus is CifsNeedNegotiate, and by making sure that generic_ip_connect is always called at least once in cifs_reconnect. Note that this is not a perfect fix for this issue. It's still possible that the NEGOTIATE reply is handled after the socket has been closed and reconnected. In that case, the socket state will look correct but it no NEGOTIATE was performed on it be for the wrong socket. In that situation though the server should just shut down the socket on the next attempted send, rather than causing the oops that occurs today. Cc: <stable@kernel.org> # .38.x: fd88ce9: [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood Reported-and-Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-11 04:14:57 +08:00
if (server->tcpStatus == CifsNeedNegotiate)
server->tcpStatus = CifsGood;
else
rc = -EHOSTDOWN;
spin_unlock(&GlobalMid_Lock);
}
return rc;
}
int
cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
struct nls_table *nls_info)
{
int rc = -ENOSYS;
struct TCP_Server_Info *server = cifs_ses_server(ses);
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
if (!ses->binding) {
ses->capabilities = server->capabilities;
if (!linuxExtEnabled)
cifs: try opening channels after mounting After doing mount() successfully we call cifs_try_adding_channels() which will open as many channels as it can. Channels are closed when the master session is closed. The master connection becomes the first channel. ,-------------> global cifs_tcp_ses_list <-------------------------. | | '- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-' (master con) (chan#1 con) (chan#2 con) | ^ ^ ^ v '--------------------|--------------------' cifs_ses | - chan_count = 3 | - chans[] ---------------------' - smb3signingkey[] (master signing key) Note how channel connections don't have sessions. That's because cifs_ses can only be part of one linked list (list_head are internal to the elements). For signing keys, each channel has its own signing key which must be used only after the channel has been bound. While it's binding it must use the master session signing key. For encryption keys, since channel connections do not have sessions attached we must now find matching session by looping over all sessions in smb2_get_enc_key(). Each channel is opened like a regular server connection but at the session setup request step it must set the SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to. Finally, while sending in compound_send_recv() for requests that aren't negprot, ses-setup or binding related, use a channel by cycling through the available ones (round-robin). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-20 12:31:10 +08:00
ses->capabilities &= (~server->vals->cap_unix);
if (ses->auth_key.response) {
cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
ses->auth_key.response);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
ses->auth_key.len = 0;
}
}
cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
server->sec_mode, server->capabilities, server->timeAdj);
if (server->ops->sess_setup)
rc = server->ops->sess_setup(xid, ses, nls_info);
if (rc)
cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
return rc;
}
static int
cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
{
ctx->sectype = ses->sectype;
/* krb5 is special, since we don't need username or pw */
if (ctx->sectype == Kerberos)
return 0;
return cifs_set_cifscreds(ctx, ses);
}
static struct cifs_tcon *
cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
{
int rc;
struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
struct cifs_ses *ses;
struct cifs_tcon *tcon = NULL;
struct smb3_fs_context *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (ctx == NULL)
return ERR_PTR(-ENOMEM);
ctx->local_nls = cifs_sb->local_nls;
ctx->linux_uid = fsuid;
ctx->cred_uid = fsuid;
ctx->UNC = master_tcon->treeName;
ctx->retry = master_tcon->retry;
ctx->nocase = master_tcon->nocase;
ctx->nohandlecache = master_tcon->nohandlecache;
ctx->local_lease = master_tcon->local_lease;
ctx->no_lease = master_tcon->no_lease;
ctx->resilient = master_tcon->use_resilient;
ctx->persistent = master_tcon->use_persistent;
ctx->handle_timeout = master_tcon->handle_timeout;
ctx->no_linux_ext = !master_tcon->unix_ext;
ctx->linux_ext = master_tcon->posix_extensions;
ctx->sectype = master_tcon->ses->sectype;
ctx->sign = master_tcon->ses->sign;
ctx->seal = master_tcon->seal;
ctx->witness = master_tcon->use_witness;
rc = cifs_set_vol_auth(ctx, master_tcon->ses);
if (rc) {
tcon = ERR_PTR(rc);
goto out;
}
/* get a reference for the same TCP session */
spin_lock(&cifs_tcp_ses_lock);
++master_tcon->ses->server->srv_count;
spin_unlock(&cifs_tcp_ses_lock);
ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
if (IS_ERR(ses)) {
tcon = (struct cifs_tcon *)ses;
cifs_put_tcp_session(master_tcon->ses->server, 0);
goto out;
}
tcon = cifs_get_tcon(ses, ctx);
if (IS_ERR(tcon)) {
cifs_put_smb_ses(ses);
goto out;
}
if (cap_unix(ses))
reset_cifs_unix_caps(0, tcon, NULL, ctx);
out:
kfree(ctx->username);
kfree_sensitive(ctx->password);
kfree(ctx);
return tcon;
}
struct cifs_tcon *
cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
{
return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
}
/* find and return a tlink with given uid */
static struct tcon_link *
tlink_rb_search(struct rb_root *root, kuid_t uid)
{
struct rb_node *node = root->rb_node;
struct tcon_link *tlink;
while (node) {
tlink = rb_entry(node, struct tcon_link, tl_rbnode);
if (uid_gt(tlink->tl_uid, uid))
node = node->rb_left;
else if (uid_lt(tlink->tl_uid, uid))
node = node->rb_right;
else
return tlink;
}
return NULL;
}
/* insert a tcon_link into the tree */
static void
tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
{
struct rb_node **new = &(root->rb_node), *parent = NULL;
struct tcon_link *tlink;
while (*new) {
tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
parent = *new;
if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
new = &((*new)->rb_left);
else
new = &((*new)->rb_right);
}
rb_link_node(&new_tlink->tl_rbnode, parent, new);
rb_insert_color(&new_tlink->tl_rbnode, root);
}
/*
* Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
* current task.
*
* If the superblock doesn't refer to a multiuser mount, then just return
* the master tcon for the mount.
*
* First, search the rbtree for an existing tcon for this fsuid. If one
* exists, then check to see if it's pending construction. If it is then wait
* for construction to complete. Once it's no longer pending, check to see if
* it failed and either return an error or retry construction, depending on
* the timeout.
*
* If one doesn't exist then insert a new tcon_link struct into the tree and
* try to construct a new one.
*/
struct tcon_link *
cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
{
int ret;
kuid_t fsuid = current_fsuid();
struct tcon_link *tlink, *newtlink;
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
spin_lock(&cifs_sb->tlink_tree_lock);
tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
if (tlink)
cifs_get_tlink(tlink);
spin_unlock(&cifs_sb->tlink_tree_lock);
if (tlink == NULL) {
newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
if (newtlink == NULL)
return ERR_PTR(-ENOMEM);
newtlink->tl_uid = fsuid;
newtlink->tl_tcon = ERR_PTR(-EACCES);
set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
cifs_get_tlink(newtlink);
spin_lock(&cifs_sb->tlink_tree_lock);
/* was one inserted after previous search? */
tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
if (tlink) {
cifs_get_tlink(tlink);
spin_unlock(&cifs_sb->tlink_tree_lock);
kfree(newtlink);
goto wait_for_construction;
}
tlink = newtlink;
tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
spin_unlock(&cifs_sb->tlink_tree_lock);
} else {
wait_for_construction:
ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
TASK_INTERRUPTIBLE);
if (ret) {
cifs_put_tlink(tlink);
sched: Remove proliferation of wait_on_bit() action functions The current "wait_on_bit" interface requires an 'action' function to be provided which does the actual waiting. There are over 20 such functions, many of them identical. Most cases can be satisfied by one of just two functions, one which uses io_schedule() and one which just uses schedule(). So: Rename wait_on_bit and wait_on_bit_lock to wait_on_bit_action and wait_on_bit_lock_action to make it explicit that they need an action function. Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io which are *not* given an action function but implicitly use a standard one. The decision to error-out if a signal is pending is now made based on the 'mode' argument rather than being encoded in the action function. All instances of the old wait_on_bit and wait_on_bit_lock which can use the new version have been changed accordingly and their action functions have been discarded. wait_on_bit{_lock} does not return any specific error code in the event of a signal so the caller must check for non-zero and interpolate their own error code as appropriate. The wait_on_bit() call in __fscache_wait_on_invalidate() was ambiguous as it specified TASK_UNINTERRUPTIBLE but used fscache_wait_bit_interruptible as an action function. David Howells confirms this should be uniformly "uninterruptible" The main remaining user of wait_on_bit{,_lock}_action is NFS which needs to use a freezer-aware schedule() call. A comment in fs/gfs2/glock.c notes that having multiple 'action' functions is useful as they display differently in the 'wchan' field of 'ps'. (and /proc/$PID/wchan). As the new bit_wait{,_io} functions are tagged "__sched", they will not show up at all, but something higher in the stack. So the distinction will still be visible, only with different function names (gds2_glock_wait versus gfs2_glock_dq_wait in the gfs2/glock.c case). Since first version of this patch (against 3.15) two new action functions appeared, on in NFS and one in CIFS. CIFS also now uses an action function that makes the same freezer aware schedule call as NFS. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: David Howells <dhowells@redhat.com> (fscache, keys) Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2) Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-07 13:16:04 +08:00
return ERR_PTR(-ERESTARTSYS);
}
/* if it's good, return it */
if (!IS_ERR(tlink->tl_tcon))
return tlink;
/* return error if we tried this already recently */
if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
cifs_put_tlink(tlink);
return ERR_PTR(-EACCES);
}
if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
goto wait_for_construction;
}
tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
if (IS_ERR(tlink->tl_tcon)) {
cifs_put_tlink(tlink);
return ERR_PTR(-EACCES);
}
return tlink;
}
/*
* periodic workqueue job that scans tcon_tree for a superblock and closes
* out tcons.
*/
static void
cifs_prune_tlinks(struct work_struct *work)
{
struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
prune_tlinks.work);
struct rb_root *root = &cifs_sb->tlink_tree;
struct rb_node *node;
struct rb_node *tmp;
struct tcon_link *tlink;
/*
* Because we drop the spinlock in the loop in order to put the tlink
* it's not guarded against removal of links from the tree. The only
* places that remove entries from the tree are this function and
* umounts. Because this function is non-reentrant and is canceled
* before umount can proceed, this is safe.
*/
spin_lock(&cifs_sb->tlink_tree_lock);
node = rb_first(root);
while (node != NULL) {
tmp = node;
node = rb_next(tmp);
tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
atomic_read(&tlink->tl_count) != 0 ||
time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
continue;
cifs_get_tlink(tlink);
clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
rb_erase(tmp, root);
spin_unlock(&cifs_sb->tlink_tree_lock);
cifs_put_tlink(tlink);
spin_lock(&cifs_sb->tlink_tree_lock);
}
spin_unlock(&cifs_sb->tlink_tree_lock);
queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
TLINK_IDLE_EXPIRE);
}
#ifdef CONFIG_CIFS_DFS_UPCALL
static void mark_tcon_tcp_ses_for_reconnect(struct cifs_tcon *tcon)
{
int i;
for (i = 0; i < tcon->ses->chan_count; i++) {
spin_lock(&GlobalMid_Lock);
if (tcon->ses->chans[i].server->tcpStatus != CifsExiting)
tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
spin_unlock(&GlobalMid_Lock);
}
}
/* Update dfs referral path of superblock */
static int update_server_fullpath(struct TCP_Server_Info *server, struct cifs_sb_info *cifs_sb,
const char *target)
{
int rc = 0;
size_t len = strlen(target);
char *refpath, *npath;
if (unlikely(len < 2 || *target != '\\'))
return -EINVAL;
if (target[1] == '\\') {
len += 1;
refpath = kmalloc(len, GFP_KERNEL);
if (!refpath)
return -ENOMEM;
scnprintf(refpath, len, "%s", target);
} else {
len += sizeof("\\");
refpath = kmalloc(len, GFP_KERNEL);
if (!refpath)
return -ENOMEM;
scnprintf(refpath, len, "\\%s", target);
}
npath = dfs_cache_canonical_path(refpath, cifs_sb->local_nls, cifs_remap(cifs_sb));
kfree(refpath);
if (IS_ERR(npath)) {
rc = PTR_ERR(npath);
} else {
mutex_lock(&server->refpath_lock);
kfree(server->leaf_fullpath);
server->leaf_fullpath = npath;
mutex_unlock(&server->refpath_lock);
server->current_fullpath = server->leaf_fullpath;
}
return rc;
}
static int target_share_matches_server(struct TCP_Server_Info *server, const char *tcp_host,
size_t tcp_host_len, char *share, bool *target_match)
{
int rc = 0;
const char *dfs_host;
size_t dfs_host_len;
*target_match = true;
extract_unc_hostname(share, &dfs_host, &dfs_host_len);
/* Check if hostnames or addresses match */
if (dfs_host_len != tcp_host_len || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) {
cifs_dbg(FYI, "%s: %.*s doesn't match %.*s\n", __func__, (int)dfs_host_len,
dfs_host, (int)tcp_host_len, tcp_host);
rc = match_target_ip(server, dfs_host, dfs_host_len, target_match);
if (rc)
cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc);
}
return rc;
}
static int __tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, char *tree, bool islink,
struct dfs_cache_tgt_list *tl)
{
int rc;
struct TCP_Server_Info *server = tcon->ses->server;
const struct smb_version_operations *ops = server->ops;
struct cifs_tcon *ipc = tcon->ses->tcon_ipc;
char *share = NULL, *prefix = NULL;
const char *tcp_host;
size_t tcp_host_len;
struct dfs_cache_tgt_iterator *tit;
bool target_match;
extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);
tit = dfs_cache_get_tgt_iterator(tl);
if (!tit) {
rc = -ENOENT;
goto out;
}
/* Try to tree connect to all dfs targets */
for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
const char *target = dfs_cache_get_tgt_name(tit);
struct dfs_cache_tgt_list ntl = DFS_CACHE_TGT_LIST_INIT(ntl);
kfree(share);
kfree(prefix);
share = prefix = NULL;
/* Check if share matches with tcp ses */
rc = dfs_cache_get_tgt_share(server->current_fullpath + 1, tit, &share, &prefix);
if (rc) {
cifs_dbg(VFS, "%s: failed to parse target share: %d\n", __func__, rc);
break;
}
rc = target_share_matches_server(server, tcp_host, tcp_host_len, share,
&target_match);
if (rc)
break;
if (!target_match) {
rc = -EHOSTUNREACH;
continue;
}
if (ipc->need_reconnect) {
scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
rc = ops->tree_connect(xid, ipc->ses, tree, ipc, cifs_sb->local_nls);
if (rc)
break;
}
scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
if (!islink) {
rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
break;
}
/*
* If no dfs referrals were returned from link target, then just do a TREE_CONNECT
* to it. Otherwise, cache the dfs referral and then mark current tcp ses for
* reconnect so either the demultiplex thread or the echo worker will reconnect to
* newly resolved target.
*/
if (dfs_cache_find(xid, tcon->ses, cifs_sb->local_nls, cifs_remap(cifs_sb), target,
NULL, &ntl)) {
rc = ops->tree_connect(xid, tcon->ses, tree, tcon, cifs_sb->local_nls);
if (rc)
continue;
rc = dfs_cache_noreq_update_tgthint(server->current_fullpath + 1, tit);
if (!rc)
rc = cifs_update_super_prepath(cifs_sb, prefix);
} else {
/* Target is another dfs share */
rc = update_server_fullpath(server, cifs_sb, target);
dfs_cache_free_tgts(tl);
if (!rc) {
rc = -EREMOTE;
list_replace_init(&ntl.tl_list, &tl->tl_list);
} else
dfs_cache_free_tgts(&ntl);
}
break;
}
out:
kfree(share);
kfree(prefix);
return rc;
}
static int tree_connect_dfs_target(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, char *tree, bool islink,
struct dfs_cache_tgt_list *tl)
{
int rc;
int num_links = 0;
struct TCP_Server_Info *server = tcon->ses->server;
do {
rc = __tree_connect_dfs_target(xid, tcon, cifs_sb, tree, islink, tl);
if (!rc || rc != -EREMOTE)
break;
} while (rc = -ELOOP, ++num_links < MAX_NESTED_LINKS);
/*
* If we couldn't tree connect to any targets from last referral path, then retry from
* original referral path.
*/
if (rc && server->current_fullpath != server->origin_fullpath) {
server->current_fullpath = server->origin_fullpath;
mark_tcon_tcp_ses_for_reconnect(tcon);
}
dfs_cache_free_tgts(tl);
return rc;
}
int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
{
int rc;
struct TCP_Server_Info *server = tcon->ses->server;
const struct smb_version_operations *ops = server->ops;
struct super_block *sb = NULL;
struct cifs_sb_info *cifs_sb;
struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
char *tree;
struct dfs_info3_param ref = {0};
tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);
if (!tree)
return -ENOMEM;
if (tcon->ipc) {
scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
goto out;
}
sb = cifs_get_tcp_super(server);
if (IS_ERR(sb)) {
rc = PTR_ERR(sb);
cifs_dbg(VFS, "%s: could not find superblock: %d\n", __func__, rc);
goto out;
}
cifs_sb = CIFS_SB(sb);
/* If it is not dfs or there was no cached dfs referral, then reconnect to same share */
if (!server->current_fullpath ||
dfs_cache_noreq_find(server->current_fullpath + 1, &ref, &tl)) {
rc = ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, cifs_sb->local_nls);
goto out;
}
rc = tree_connect_dfs_target(xid, tcon, cifs_sb, tree, ref.server_type == DFS_TYPE_LINK,
&tl);
free_dfs_info_param(&ref);
out:
kfree(tree);
cifs_put_tcp_super(sb);
return rc;
}
#else
int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
{
const struct smb_version_operations *ops = tcon->ses->server->ops;
return ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
}
#endif