Commit Graph

96 Commits

Author SHA1 Message Date
Enzo Matsumiya d7173623bf cifs: use ALIGN() and round_up() macros
Improve code readability by using existing macros:

Replace hardcoded alignment computations (e.g. (len + 7) & ~0x7) by
ALIGN()/IS_ALIGNED() macros.

Also replace (DIV_ROUND_UP(len, 8) * 8) with ALIGN(len, 8), which, if
not optimized by the compiler, has the overhead of a multiplication
and a division. Do the same for roundup() by replacing it by round_up()
(division-less version, but requires the multiple to be a power of 2,
which is always the case for us).

And remove some unnecessary checks where !IS_ALIGNED() would fit, but
calling round_up() directly is fine as it's a no-op if the value is
already aligned.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-10-13 09:36:39 -05:00
Enzo Matsumiya 1f3d5477b9 cifs: secmech: use shash_desc directly, remove sdesc
The struct sdesc is just a wrapper around shash_desc, with exact same
memory layout. Replace the hashing TFMs with shash_desc as it's what's
passed to the crypto API anyway.

Also remove the crypto_shash pointers as they can be accessed via
shash_desc->tfm (and are actually only used in the setkey calls).

Adapt cifs_{alloc,free}_hash functions to this change.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-10-07 23:08:39 -05:00
Enzo Matsumiya 68ed14496b cifs: remove unused server parameter from calc_smb_size()
This parameter is unused by the called function

Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-08-17 18:07:13 -05:00
Ronnie Sahlberg 05b98fd2da cifs: Move cached-dir functions into a separate file
Also rename crfid to cfid to have consistent naming for this variable.

This commit does not change any logic.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-08-11 10:33:18 -05:00
Enzo Matsumiya da3847894f smb2: small refactor in smb2_check_message()
If the command is SMB2_IOCTL, OutputLength and OutputContext are
optional and can be zero, so return early and skip calculated length
check.

Move the mismatched length message to the end of the check, to avoid
unnecessary logs when the check was not a real miscalculation.

Also change the pr_warn_once() to a pr_warn() so we're sure to get a
log for the real mismatches.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-08-01 01:34:44 -05:00
Yu Zhe 0f46608ae7 cifs: remove unnecessary type castings
remove unnecessary void* type castings.

Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-08-01 01:34:44 -05:00
Steve French 35a2b533a2 smb3: add trace point for oplock not found
In order to debug problems with server potentially
sending us an oplock that we don't recognize (or a race
with close and oplock break) it would be helpful to have
a dynamic trace point for this case.  New tracepoint
is called trace_smb3_oplock_not_found

Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-22 00:46:08 -05:00
Steve French fb253d5ba3 smb3: add trace point for lease not found issue
When trying to debug problems with server sending us a
lease we don't recognize, it would be helpful to have
a dynamic trace point for this case.  New tracepoint
is called trace_smb3_lease_not_found

Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-21 23:56:16 -05:00
Enzo Matsumiya 71081e7ac1 cifs: print TIDs as hex
Makes these debug messages easier to read

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-05-20 17:46:22 -05:00
Jakob Koschel 00c796eecb cifs: remove check of list iterator against head past the loop body
When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.

While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-04-04 12:01:22 -05:00
Steve French 113be37d87 [smb3] move more common protocol header definitions to smbfs_common
We have duplicated definitions for various SMB3 PDUs in
fs/ksmbd and fs/cifs.  Some had already been moved to
fs/smbfs_common/smb2pdu.h

Move definitions for
- error response
- query info and various related protocol flags
- various lease handling flags and the create lease context

to smbfs_common/smb2pdu.h to reduce code duplication

Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-25 10:40:56 -05:00
Paulo Alcantara 351a59dace cifs: fix bad fids sent over wire
The client used to partially convert the fids to le64, while storing
or sending them by using host endianness.  This broke the client on
big-endian machines.  Instead of converting them to le64, store them
as opaque integers and then avoid byteswapping when sending them over
wire.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-23 15:20:14 -05:00
Yang Li 3ac5f2f257 cifs: Fix smb311_update_preauth_hash() kernel-doc comment
Add the description of @server in smb311_update_preauth_hash()
kernel-doc comment to remove warning found by running scripts/kernel-doc,
which is caused by using 'make W=1'.
fs/cifs/smb2misc.c:856: warning: Function parameter or member 'server'
not described in 'smb311_update_preauth_hash'

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-15 10:08:33 -06:00
Shyam Prasad N f486ef8e20 cifs: use the chans_need_reconnect bitmap for reconnect status
We use the concept of "binding" when one of the secondary channel
is in the process of connecting/reconnecting to the server. Till this
binding process completes, and the channel is bound to an existing session,
we redirect traffic from other established channels on the binding channel,
effectively blocking all traffic till individual channels get reconnected.

With my last set of commits, we can get rid of this binding serialization.
We now have a bitmap of connection states for each channel. We will use
this bitmap instead for tracking channel status.

Having a bitmap also now enables us to keep the session alive, as long
as even a single channel underneath is alive.

Unfortunately, this also meant that we need to supply the tcp connection
info for the channel during all negotiate and session setup functions.
These changes have resulted in a slightly bigger code churn.
However, I expect perf and robustness improvements in the mchan scenario
after this change.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-02 20:38:46 -06:00
Ronnie Sahlberg c462870bf8 cifs: Move SMB2_Create definitions to the shared area
Move all SMB2_Create definitions (except contexts) into the shared area.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 09:55:36 -05:00
Ronnie Sahlberg 0d35e382e4 cifs: Create a new shared file holding smb2 pdu definitions
This file will contain all the definitions we need for SMB2 packets
and will follow the naming convention of MS-SMB2.PDF as closely
as possible to make it easier to cross-reference beween the definitions
and the standard.

The content of this file will mostly consist of migration of existing
definitions in the cifs/smb2.pdu.h and ksmbd/smb2pdu.h files
with some additional tweaks as the two files have diverged.

This patch introduces the new smbfs_common/smb2pdu.h file
and migrates the SMB2 header as well as TREE_CONNECT and TREE_DISCONNECT
to the shared file.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-11-05 09:50:57 -05:00
Steve French 099dd788e3 cifs: remove pathname for file from SPDX header
checkpatch complains about source files with filenames (e.g. in
these cases just below the SPDX header in comments at the top of
various files in fs/cifs). It also is helpful to change this now
so will be less confusing when the parent directory is renamed
e.g. from fs/cifs to fs/smb_client (or fs/smbfs)

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-09-13 14:51:10 -05:00
Dan Carpenter 1689b0b554 cifs: fix NULL dereference in smb2_check_message()
This code sets "ses" to NULL which will lead to a NULL dereference on
the second iteration through the loop.

Fixes: 85346c17e425 ("cifs: convert list_for_each to entry variant in smb2misc.c")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-23 13:04:36 -05:00
Steve French 929be906fa cifs: use SPDX-Licence-Identifier
Add SPDX license identifier and replace license boilerplate.
Corrects various checkpatch errors with the older format for
noting the LGPL license.

Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:17 -05:00
Baokun Li 647f592734 cifs: convert list_for_each to entry variant in smb2misc.c
convert list_for_each() to list_for_each_entry() where
applicable.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-06-20 21:28:17 -05:00
Ronnie Sahlberg ed20f54a3c cifs: add a timestamp to track when the lease of the cached dir was taken
and clear the timestamp when we receive a lease break.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-04-25 16:28:23 -05:00
Vincent Whitchurch 219481a8f9 cifs: Silently ignore unknown oplock break handle
Make SMB2 not print out an error when an oplock break is received for an
unknown handle, similar to SMB1.  The debug message which is printed for
these unknown handles may also be misleading, so fix that too.

The SMB2 lease break path is not affected by this patch.

Without this, a program which writes to a file from one thread, and
opens, reads, and writes the same file from another thread triggers the
below errors several times a minute when run against a Samba server
configured with "smb2 leases = no".

 CIFS: VFS: \\192.168.0.1 No task to wake, unknown frame received! NumMids 2
 00000000: 424d53fe 00000040 00000000 00000012  .SMB@...........
 00000010: 00000001 00000000 ffffffff ffffffff  ................
 00000020: 00000000 00000000 00000000 00000000  ................
 00000030: 00000000 00000000 00000000 00000000  ................

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-26 18:05:26 -05:00
Paulo Alcantara 04ad69c342 cifs: do not send close in compound create+close requests
In case of interrupted syscalls, prevent sending CLOSE commands for
compound CREATE+CLOSE requests by introducing an
CIFS_CP_CREATE_CLOSE_OP flag to indicate lower layers that it should
not send a CLOSE command to the MIDs corresponding the compound
CREATE+CLOSE request.

A simple reproducer:

    #!/bin/bash

    mount //server/share /mnt -o username=foo,password=***
    tc qdisc add dev eth0 root netem delay 450ms
    stat -f /mnt &>/dev/null & pid=$!
    sleep 0.01
    kill $pid
    tc qdisc del dev eth0 root
    umount /mnt

Before patch:

    ...
    6 0.256893470 192.168.122.2 → 192.168.122.15 SMB2 402 Create Request File: ;GetInfo Request FS_INFO/FileFsFullSizeInformation;Close Request
    7 0.257144491 192.168.122.15 → 192.168.122.2 SMB2 498 Create Response File: ;GetInfo Response;Close Response
    9 0.260798209 192.168.122.2 → 192.168.122.15 SMB2 146 Close Request File:
   10 0.260841089 192.168.122.15 → 192.168.122.2 SMB2 130 Close Response, Error: STATUS_FILE_CLOSED

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:23:22 -06:00
Paulo Alcantara bf1bc694b6 cifs: print MIDs in decimal notation
The MIDs are mostly printed as decimal, so let's make it consistent.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-08 21:22:31 -06:00
Steve French 607dfc79c3 cifs: remove various function description warnings
When compiling with W=1 I noticed various functions that
did not follow proper style in describing (in the comments)
the parameters passed in to the function. For example:

fs/cifs/inode.c:2236: warning: Function parameter or member 'mode' not described in 'cifs_wait_bit_killable'

I did not address the style warnings in two of the six files
(connect.c and misc.c) in order to reduce risk of merge
conflict with pending patches. We can update those later.

Signed-off-by: Steve French <stfrench@microsoft.com>
2020-12-14 09:16:23 -06:00
Steve French 145024e3e4 SMB3.1.1: update comments clarifying SPNEGO info in negprot response
Trivial changes to clarify confusing comment about
SPNEGO blog (and also one length comparisons in negotiate
context parsing).

Suggested-by: Tom Talpey <tom@talpey.com>
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-12-13 19:12:07 -06:00
Steve French bc7c4129d4 SMB3.1.1: remove confusing mount warning when no SPNEGO info on negprot rsp
Azure does not send an SPNEGO blob in the negotiate protocol response,
so we shouldn't assume that it is there when validating the location
of the first negotiate context.  This avoids the potential confusing
mount warning:

   CIFS: Invalid negotiate context offset

CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-12-13 19:12:07 -06:00
Paul Aurich baf57b56d3 cifs: Fix leak when handling lease break for cached root fid
Handling a lease break for the cached root didn't free the
smb2_lease_break_work allocation, resulting in a leak:

    unreferenced object 0xffff98383a5af480 (size 128):
      comm "cifsd", pid 684, jiffies 4294936606 (age 534.868s)
      hex dump (first 32 bytes):
        c0 ff ff ff 1f 00 00 00 88 f4 5a 3a 38 98 ff ff  ..........Z:8...
        88 f4 5a 3a 38 98 ff ff 80 88 d6 8a ff ff ff ff  ..Z:8...........
      backtrace:
        [<0000000068957336>] smb2_is_valid_oplock_break+0x1fa/0x8c0
        [<0000000073b70b9e>] cifs_demultiplex_thread+0x73d/0xcc0
        [<00000000905fa372>] kthread+0x11c/0x150
        [<0000000079378e4e>] ret_from_fork+0x22/0x30

Avoid this leak by only allocating when necessary.

Fixes: a93864d939 ("cifs: add lease tracking to the cached root fid")
Signed-off-by: Paul Aurich <paul@darkrain42.org>
CC: Stable <stable@vger.kernel.org> # v4.18+
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-08-02 18:00:25 -05:00
Steve French 8668115cf2 smb3: fix unneeded error message on change notify
We should not be logging a warning repeatedly on change notify.

CC: Stable <stable@vger.kernel.org> # v5.6+
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2020-07-08 03:59:02 -05:00
Joe Perches a0a3036b81 cifs: Standardize logging output
Use pr_fmt to standardize all logging for fs/cifs.

Some logging output had no CIFS: specific prefix.

Now all output has one of three prefixes:

o CIFS:
o CIFS: VFS:
o Root-CIFS:

Miscellanea:

o Convert printks to pr_<level>
o Neaten macro definitions
o Remove embedded CIFS: prefixes from formats
o Convert "illegal" to "invalid"
o Coalesce formats
o Add missing '\n' format terminations
o Consolidate multiple cifs_dbg continuations into single calls
o More consistent use of upper case first word output logging
o Multiline statement argument alignment and wrapping

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 00:10:18 -05:00
Aurelien Aptel e79b0332ae cifs: ignore cached share root handle closing errors
Fix tcon use-after-free and NULL ptr deref.

Customer system crashes with the following kernel log:

[462233.169868] CIFS VFS: Cancelling wait for mid 4894753 cmd: 14       => a QUERY DIR
[462233.228045] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.305922] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.306205] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347060] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347107] CIFS VFS: Close unmatched open
[462233.347113] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
...
    [exception RIP: cifs_put_tcon+0xa0] (this is doing tcon->ses->server)
 #6 [...] smb2_cancelled_close_fid at ... [cifs]
 #7 [...] process_one_work at ...
 #8 [...] worker_thread at ...
 #9 [...] kthread at ...

The most likely explanation we have is:

* When we put the last reference of a tcon (refcount=0), we close the
  cached share root handle.
* If closing a handle is interrupted, SMB2_close() will
  queue a SMB2_close() in a work thread.
* The queued object keeps a tcon ref so we bump the tcon
  refcount, jumping from 0 to 1.
* We reach the end of cifs_put_tcon(), we free the tcon object despite
  it now having a refcount of 1.
* The queued work now runs, but the tcon, ses & server was freed in
  the meantime resulting in a crash.

THREAD 1
========
cifs_put_tcon                 => tcon refcount reach 0
  SMB2_tdis
   close_shroot_lease
    close_shroot_lease_locked => if cached root has lease && refcount = 0
     smb2_close_cached_fid    => if cached root valid
      SMB2_close              => retry close in a thread if interrupted
       smb2_handle_cancelled_close
        __smb2_handle_cancelled_close    => !! tcon refcount bump 0 => 1 !!
         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
         queue_work(cifsiod_wq, &cancelled->work) => queue work
 tconInfoFree(tcon);    ==> freed!
 cifs_put_smb_ses(ses); ==> freed!

THREAD 2 (workqueue)
========
smb2_cancelled_close_fid
  SMB2_close(0, cancelled->tcon, ...); => use-after-free of tcon
  cifs_put_tcon(cancelled->tcon);      => tcon refcount reach 0 second time
  *CRASH*

Fixes: d919131935 ("CIFS: Close cached root handle only if it has a lease")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-04-07 12:40:40 -05:00
Paulo Alcantara (SUSE) 0a5a98863c cifs: Fix memory allocation in __smb2_handle_cancelled_cmd()
__smb2_handle_cancelled_cmd() is called under a spin lock held in
cifs_mid_q_entry_release(), so make its memory allocation GFP_ATOMIC.

This issue was observed when running xfstests generic/028:

[ 1722.589204] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72064 cmd: 5
[ 1722.590687] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72065 cmd: 17
[ 1722.593529] CIFS VFS: \\192.168.30.26 Cancelling wait for mid 72066 cmd: 6
[ 1723.039014] BUG: sleeping function called from invalid context at mm/slab.h:565
[ 1723.040710] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 30877, name: cifsd
[ 1723.045098] CPU: 3 PID: 30877 Comm: cifsd Not tainted 5.5.0-rc4+ #313
[ 1723.046256] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 1723.048221] Call Trace:
[ 1723.048689]  dump_stack+0x97/0xe0
[ 1723.049268]  ___might_sleep.cold+0xd1/0xe1
[ 1723.050069]  kmem_cache_alloc_trace+0x204/0x2b0
[ 1723.051051]  __smb2_handle_cancelled_cmd+0x40/0x140 [cifs]
[ 1723.052137]  smb2_handle_cancelled_mid+0xf6/0x120 [cifs]
[ 1723.053247]  cifs_mid_q_entry_release+0x44d/0x630 [cifs]
[ 1723.054351]  ? cifs_reconnect+0x26a/0x1620 [cifs]
[ 1723.055325]  cifs_demultiplex_thread+0xad4/0x14a0 [cifs]
[ 1723.056458]  ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.057365]  ? kvm_sched_clock_read+0x14/0x30
[ 1723.058197]  ? sched_clock+0x5/0x10
[ 1723.058838]  ? sched_clock_cpu+0x18/0x110
[ 1723.059629]  ? lockdep_hardirqs_on+0x17d/0x250
[ 1723.060456]  kthread+0x1ab/0x200
[ 1723.061149]  ? cifs_handle_standard+0x2c0/0x2c0 [cifs]
[ 1723.062078]  ? kthread_create_on_node+0xd0/0xd0
[ 1723.062897]  ret_from_fork+0x3a/0x50

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Fixes: 9150c3adbf ("CIFS: Close open handle after interrupted close")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2020-01-26 19:24:17 -06:00
Pavel Shilovsky 9bd4540836 CIFS: Properly process SMB3 lease breaks
Currenly we doesn't assume that a server may break a lease
from RWH to RW which causes us setting a wrong lease state
on a file and thus mistakenly flushing data and byte-range
locks and purging cached data on the client. This leads to
performance degradation because subsequent IOs go directly
to the server.

Fix this by propagating new lease state and epoch values
to the oplock break handler through cifsFileInfo structure
and removing the use of cifsInodeInfo flags for that. It
allows to avoid some races of several lease/oplock breaks
using those flags in parallel.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25 01:17:12 -06:00
Aurelien Aptel d70e9fa558 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>
2019-11-25 01:16:30 -06:00
Pavel Shilovsky fa9c236249 CIFS: Fix SMB2 oplock break processing
Even when mounting modern protocol version the server may be
configured without supporting SMB2.1 leases and the client
uses SMB2 oplock to optimize IO performance through local caching.

However there is a problem in oplock break handling that leads
to missing a break notification on the client who has a file
opened. It latter causes big latencies to other clients that
are trying to open the same file.

The problem reproduces when there are multiple shares from the
same server mounted on the client. The processing code tries to
match persistent and volatile file ids from the break notification
with an open file but it skips all share besides the first one.
Fix this by looking up in all shares belonging to the server that
issued the oplock break.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25 01:16:30 -06:00
Ronnie Sahlberg 87bc2376ff smb3: add debug messages for closing unmatched open
Helps distinguish between an interrupted close and a truly
unmatched open.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25 01:14:53 -06:00
Pavel Shilovsky 9150c3adbf CIFS: Close open handle after interrupted close
If Close command is interrupted before sending a request
to the server the client ends up leaking an open file
handle. This wastes server resources and can potentially
block applications that try to remove the file or any
directory containing this file.

Fix this by putting the close command into a worker queue,
so another thread retries it later.

Cc: Stable <stable@vger.kernel.org>
Tested-by: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25 01:14:53 -06:00
Steve French 037d050724 smb3: remove confusing dmesg when mounting with encryption ("seal")
The smb2/smb3 message checking code was logging to dmesg when mounting
with encryption ("seal") for compounded SMB3 requests.  When encrypted
the whole frame (including potentially multiple compounds) is read
so the length field is longer than in the case of non-encrypted
case (where length field will match the the calculated length for
the particular SMB3 request in the compound being validated).

Avoids the warning on mount (with "seal"):

   "srv rsp padded more than expected. Length 384 not ..."

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-11-25 01:14:53 -06:00
Aurelien Aptel b98749cac4 CIFS: keep FileInfo handle live during oplock break
In the oplock break handler, writing pending changes from pages puts
the FileInfo handle. If the refcount reaches zero it closes the handle
and waits for any oplock break handler to return, thus causing a deadlock.

To prevent this situation:

* We add a wait flag to cifsFileInfo_put() to decide whether we should
  wait for running/pending oplock break handlers

* We keep an additionnal reference of the SMB FileInfo handle so that
  for the rest of the handler putting the handle won't close it.
  - The ref is bumped everytime we queue the handler via the
    cifs_queue_oplock_break() helper.
  - The ref is decremented at the end of the handler

This bug was triggered by xfstest 464.

Also important fix to address the various reports of
oops in smb2_push_mandatory_locks

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-04-16 09:38:38 -05:00
Pavel Shilovsky 7b9b9edb49 CIFS: Do not reset lease state to NONE on lease break
Currently on lease break the client sets a caching level twice:
when oplock is detected and when oplock is processed. While the
1st attempt sets the level to the value provided by the server,
the 2nd one resets the level to None unconditionally.
This happens because the oplock/lease processing code was changed
to avoid races between page cache flushes and oplock breaks.
The commit c11f1df500 ("cifs: Wait for writebacks to complete
before attempting write.") fixed the races for oplocks but didn't
apply the same changes for leases resulting in overwriting the
server granted value to None. Fix this by properly processing
lease breaks.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2019-03-04 20:05:35 -06:00
Ronnie Sahlberg eca0045238 cifs: add credits from unmatched responses/messages
We should add any credits granted to us from unmatched server responses.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-03-04 20:05:34 -06:00
Ronnie Sahlberg 2e5700bdde smb3: add credits we receive from oplock/break PDUs
Otherwise we gradually leak credits leading to potential
hung session.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-01-24 14:52:06 -06:00
Steve French 25f2573512 smb3: minor debugging clarifications in rfc1001 len processing
I ran into some cases where server was returning the wrong length
on frames but I couldn't easily match them to the command in the
network trace (or server logs) since I need the command and/or
multiplex id to find the offending SMB2/SMB3 command.  Add these
two fields to the log message. In the case of padding too much
it may not be a problem in all cases but might have correlated
to a network disconnect case in some problems we have been
looking at. In the case of frame too short is even more important.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-09-02 23:21:42 -05:00
Ronnie Sahlberg e6c47dd0da cifs: check if SMB2 PDU size has been padded and suppress the warning
Some SMB2/3 servers, Win2016 but possibly others too, adds padding
not only between PDUs in a compound but also to the final PDU.
This padding extends the PDU to a multiple of 8 bytes.

Check if the unexpected length looks like this might be the case
and avoid triggering the log messages for :

  "SMB2 server sent bad RFC1001 len %d not %d\n"

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-23 15:10:46 -05:00
Steve French 0fdfef9aa7 smb3: simplify code by removing CONFIG_CIFS_SMB311
We really, really want to be encouraging use of secure dialects,
and SMB3.1.1 offers useful security features, and will soon
be the recommended dialect for many use cases. Simplify the code
by removing the CONFIG_CIFS_SMB311 ifdef so users don't disable
it in the build, and create compatibility and/or security issues
with modern servers - many of which have been supporting this
dialect for multiple years.

Also clarify some of the Kconfig text for cifs.ko about
SMB3.1.1 and current supported features in the module.

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07 14:15:56 -05:00
Steve French d819d298c7 smb3: fix corrupt path in subdirs on smb311 with posix
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15 02:38:08 -05:00
Ronnie Sahlberg a93864d939 cifs: add lease tracking to the cached root fid
Use a read lease for the cached root fid so that we can detect
when the content of the directory changes (via a break) at which time
we close the handle. On next access to the root the handle will be reopened
and cached again.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-15 02:38:07 -05:00
Aurelien Aptel 8ddecf5fd7 CIFS: Fix NULL ptr deref
cifs->master_tlink is NULL against Win Server 2016 (which is
strange.. not sure why) and is dereferenced in cifs_sb_master_tcon().

move master_tlink getter to cifsglob.h so it can be used from
smb2misc.c

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-06-07 08:31:31 -05:00
Ronnie Sahlberg 8ce79ec359 cifs: update multiplex loop to handle compounded responses
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-06-02 18:36:26 -05:00
Ronnie Sahlberg 1fc6ad2f10 cifs: remove header_preamble_size where it is always 0
Since header_preamble_size is 0 for SMB2+ we can remove it in those
code paths that are only invoked from SMB2.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-06-01 09:14:30 -05:00