There is a current limit of 1920 registered dmb buffers per ISM device
for smc-d. One link group can contain 255 connections, each connection
is using one dmb buffer. When the connection is closed then the
registered buffer is held in a queue and is reused by the next
connection. When a link group is 'full' then another link group is
created and uses an own buffer pool. The link groups are added to a
list using list_add() which puts a new link group to the first position
in the list.
In the situation that many connections are opened (>1920) and a few of
them stay open while others are closed quickly we end up with at least 8
link groups. For a new connection a matching link group is looked up,
iterating over the list of link groups. The trailing 7 link groups
all have registered dmb buffers which could be reused, while the first
link group has only a few dmb buffers and then hit the 1920 limit.
Because the first link group is not full (255 connection limit not
reached) it is chosen and finally the connection falls back to TCP
because there is no dmb buffer available in this link group.
There are multiple ways to fix that: using list_add_tail() allows
to scan older link groups first for free buffers which ensures that
buffers are reused first. This fixes the problem for smc-r link groups
as well. For smc-d there is an even better way to address this problem
because smc-d does not have the 255 connections per link group limit.
So fix the problem for smc-d by allowing large link groups.
Fixes: c6ba7c9ba4 ("net/smc: add base infrastructure for SMC-D and ISM")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To get a send slot smc_wr_tx_get_free_slot() is called, which might
wait for a free slot. When smc_wr_tx_get_free_slot() returns there is a
check if the connection was killed in the meantime. In that case don't
only return an error, but also put back the free slot.
Fixes: b290098092 ("net/smc: cancel send and receive for terminated socket")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rxrpc_sendmsg() returns EPIPE if there's an outstanding error, such as if
rxrpc_recvmsg() indicating ENODATA if there's nothing for it to read.
Change rxrpc_recvmsg() to return EAGAIN instead if there's nothing to read
as this particular error doesn't get stored in ->sk_err by the networking
core.
Also change rxrpc_sendmsg() so that it doesn't fail with delayed receive
errors (there's no way for it to report which call, if any, the error was
caused by).
Fixes: 17926a7932 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a listen socket is closed then all non-accepted sockets in its
accept queue are to be released. Inside __smc_release() the helper
smc_restore_fallback_changes() restores the changes done to the socket
without to check if the clcsocket has a file set. This can result in
a crash. Fix this by checking the file pointer first.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: f536dffc0b ("net/smc: fix closing of fallback SMC sockets")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Two buffers are allocated for each SMC connection. Each buffer is
added to a buffer list after creation. When the second buffer
allocation fails, the first buffer is freed but not deleted from
the list. This might result in crashes when another connection picks
up the freed buffer later and starts to work with it.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 6511aad3f0 ("net/smc: change smc_buf_free function parameters")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The dma related ...sync_sg... functions check the link state before the
dma function is actually called. But the check in smc_link_usable()
allows links in ACTIVATING state which are not yet mapped to dma memory.
Under high load it may happen that the sync_sg functions are called for
such a link which results in an debug output like
DMA-API: mlx5_core 0002:00:00.0: device driver tries to sync
DMA memory it has not allocated [device address=0x0000000103370000]
[size=65536 bytes]
To fix that introduce a helper to check for the link state ACTIVE and
use it where appropriate. And move the link state update to ACTIVATING
to the end of smcr_link_init() when most initial setup is done.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: d854fcbfae ("net/smc: add new link state and related helpers")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As smc client the delete link requests are assigned to the flow when
_any_ flow is active. This may break other flows that do not expect
delete link requests during their handling. Fix that by assigning the
request only when an add link flow is active. With that fix the code
for smc client and smc server is the same, so remove the separate
handling.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 9ec6bf19ec ("net/smc: llc_del_link_work and use the LLC flow for delete link")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a new ib device is up smc will send an add link invitation to the
peer if needed. This is currently done with rudimentary flow control.
Under high workload these add link invitations can disturb other llc
flows because they arrive unexpected. Fix this by integrating the
invitations into the normal llc event flow and handle them as a flow.
While at it, check for already assigned requests in the flow before
the new add link request is assigned.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 1f90a05d9f ("net/smc: add smcr_port_add() and smcr_link_up() processing")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To be save from unexpected or late llc response messages check if the
arrived message fits to the current flow type and drop out-of-flow
messages. And drop it when there is already a response assigned to
the flow.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: ef79d439cd ("net/smc: process llc responses in tasklet context")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before an smc ib device is used the first time for an smc link it is
lazily initialized. When there are 2 active link groups and a new ib
device is brought online then it might happen that 2 link creations run
in parallel and enter smc_ib_setup_per_ibdev(). Both allocate new send
and receive completion queues on the device, but only one set of them
keeps assigned and the other leaks.
Fix that by protecting the setup and cleanup code using a mutex.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: f3c1deddb2 ("net/smc: separate function for link initialization")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For new rdma connections the SMC server assigns the link and sends the
link data in the clc accept message. To match the correct link use not
only the qp_num but also the gid and the mac of the links. If there are
equal qp_nums for different links the wrong link would be chosen.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 0fb0b02bd6 ("net/smc: adapt SMC client code to use the LLC flow")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a link-down condition we notify the SMC server and expect that the
server will finally trigger the link clear processing on the client
side. This could fail when anything along this notification path goes
wrong. Clear the link as part of SMC client link-down processing to
prevent dangling links.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 541afa10c1 ("net/smc: add smcr_port_err() and smcr_link_down() processing")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A delete link could arrive during confirm link processing. Handle this
situation directly in smc_llc_srv_conf_link() rather than using the
logic in smc_llc_wait() to avoid the unexpected message handling there.
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Fixes: 1551c95b61 ("net/smc: final part of add link processing as SMC server")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Validate MAC address before copying the same to outgoing frame
skb destination address. Since a node can have zero mac
address for Link B until a valid frame is received over
that link, this fix address the issue of a zero MAC address
being in the packet.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For small Ethernet frames with size less than minimum size 66 for HSR
vs 60 for regular Ethernet frames, hsr driver currently doesn't pad the
frame to make it minimum size. This results in incorrect LSDU size being
populated in the HSR tag for these frames. Fix this by padding the frame
to the minimum size applicable for HSR.
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When nfc_register_device fails in nci_register_device,
destroy_workqueue() shouled be called to destroy ndev->tx_wq.
Fixes: 3c1c0f5dc8 ("NFC: NCI: Fix nci_register_device init sequence")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
KASAN report null-ptr-deref error when register_netdev() failed:
KASAN: null-ptr-deref in range [0x00000000000003c0-0x00000000000003c7]
CPU: 2 PID: 422 Comm: ip Not tainted 5.8.0-rc4+ #12
Call Trace:
ip6gre_init_net+0x4ab/0x580
? ip6gre_tunnel_uninit+0x3f0/0x3f0
ops_init+0xa8/0x3c0
setup_net+0x2de/0x7e0
? rcu_read_lock_bh_held+0xb0/0xb0
? ops_init+0x3c0/0x3c0
? kasan_unpoison_shadow+0x33/0x40
? __kasan_kmalloc.constprop.0+0xc2/0xd0
copy_net_ns+0x27d/0x530
create_new_namespaces+0x382/0xa30
unshare_nsproxy_namespaces+0xa1/0x1d0
ksys_unshare+0x39c/0x780
? walk_process_tree+0x2a0/0x2a0
? trace_hardirqs_on+0x4a/0x1b0
? _raw_spin_unlock_irq+0x1f/0x30
? syscall_trace_enter+0x1a7/0x330
? do_syscall_64+0x1c/0xa0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x56/0xa0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
ip6gre_tunnel_uninit() has set 'ign->fb_tunnel_dev' to NULL, later
access to ign->fb_tunnel_dev cause null-ptr-deref. Fix it by saving
'ign->fb_tunnel_dev' to local variable ndev.
Fixes: dafabb6590 ("ip6_gre: fix use-after-free in ip6gre_tunnel_lookup()")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Restore previous behavior of CAP_SYS_ADMIN wrt loading networking
BPF programs, from Maciej Żenczykowski.
2) Fix dropped broadcasts in mac80211 code, from Seevalamuthu
Mariappan.
3) Slay memory leak in nl80211 bss color attribute parsing code, from
Luca Coelho.
4) Get route from skb properly in ip_route_use_hint(), from Miaohe Lin.
5) Don't allow anything other than ARPHRD_ETHER in llc code, from Eric
Dumazet.
6) xsk code dips too deeply into DMA mapping implementation internals.
Add dma_need_sync and use it. From Christoph Hellwig
7) Enforce power-of-2 for BPF ringbuf sizes. From Andrii Nakryiko.
8) Check for disallowed attributes when loading flow dissector BPF
programs. From Lorenz Bauer.
9) Correct packet injection to L3 tunnel devices via AF_PACKET, from
Jason A. Donenfeld.
10) Don't advertise checksum offload on ipa devices that don't support
it. From Alex Elder.
11) Resolve several issues in TCP MD5 signature support. Missing memory
barriers, bogus options emitted when using syncookies, and failure
to allow md5 key changes in established states. All from Eric
Dumazet.
12) Fix interface leak in hsr code, from Taehee Yoo.
13) VF reset fixes in hns3 driver, from Huazhong Tan.
14) Make loopback work again with ipv6 anycast, from David Ahern.
15) Fix TX starvation under high load in fec driver, from Tobias
Waldekranz.
16) MLD2 payload lengths not checked properly in bridge multicast code,
from Linus Lüssing.
17) Packet scheduler code that wants to find the inner protocol
currently only works for one level of VLAN encapsulation. Allow
Q-in-Q situations to work properly here, from Toke
Høiland-Jørgensen.
18) Fix route leak in l2tp, from Xin Long.
19) Resolve conflict between the sk->sk_user_data usage of bpf reuseport
support and various protocols. From Martin KaFai Lau.
20) Fix socket cgroup v2 reference counting in some situations, from
Cong Wang.
21) Cure memory leak in mlx5 connection tracking offload support, from
Eli Britstein.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
mlxsw: pci: Fix use-after-free in case of failed devlink reload
mlxsw: spectrum_router: Remove inappropriate usage of WARN_ON()
net: macb: fix call to pm_runtime in the suspend/resume functions
net: macb: fix macb_suspend() by removing call to netif_carrier_off()
net: macb: fix macb_get/set_wol() when moving to phylink
net: macb: mark device wake capable when "magic-packet" property present
net: macb: fix wakeup test in runtime suspend/resume routines
bnxt_en: fix NULL dereference in case SR-IOV configuration fails
libbpf: Fix libbpf hashmap on (I)LP32 architectures
net/mlx5e: CT: Fix memory leak in cleanup
net/mlx5e: Fix port buffers cell size value
net/mlx5e: Fix 50G per lane indication
net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash
net/mlx5e: Fix VXLAN configuration restore after function reload
net/mlx5e: Fix usage of rcu-protected pointer
net/mxl5e: Verify that rpriv is not NULL
net/mlx5: E-Switch, Fix vlan or qos setting in legacy mode
net/mlx5: Fix eeprom support for SFP module
cgroup: Fix sock_cgroup_data on big-endian.
selftests: bpf: Fix detach from sockmap tests
...
Reshuffle the (__)kernel_read and (__)kernel_write helpers, and ensure
all users of in-kernel file I/O use them if they don't use iov_iter
based methods already.
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Merge tag 'cleanup-kernel_read_write' of git://git.infradead.org/users/hch/misc
Pull in-kernel read and write op cleanups from Christoph Hellwig:
"Cleanup in-kernel read and write operations
Reshuffle the (__)kernel_read and (__)kernel_write helpers, and ensure
all users of in-kernel file I/O use them if they don't use iov_iter
based methods already.
The new WARN_ONs in combination with syzcaller already found a missing
input validation in 9p. The fix should be on your way through the
maintainer ASAP".
[ This is prep-work for the real changes coming 5.9 ]
* tag 'cleanup-kernel_read_write' of git://git.infradead.org/users/hch/misc:
fs: remove __vfs_read
fs: implement kernel_read using __kernel_read
integrity/ima: switch to using __kernel_read
fs: add a __kernel_read helper
fs: remove __vfs_write
fs: implement kernel_write using __kernel_write
fs: check FMODE_WRITE in __kernel_write
fs: unexport __kernel_write
bpfilter: switch to kernel_write
autofs: switch to kernel_write
cachefiles: switch to kernel_write
Several users of kallsyms_show_value() were performing checks not
during "open". Refactor everything needed to gain proper checks against
file->f_cred for modules, kprobes, and bpf.
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Merge tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull kallsyms fix from Kees Cook:
"Refactor kallsyms_show_value() users for correct cred.
I'm not delighted by the timing of getting these changes to you, but
it does fix a handful of kernel address exposures, and no one has
screamed yet at the patches.
Several users of kallsyms_show_value() were performing checks not
during "open". Refactor everything needed to gain proper checks
against file->f_cred for modules, kprobes, and bpf"
* tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests: kmod: Add module address visibility test
bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok()
kprobes: Do not expose probe addresses to non-CAP_SYSLOG
module: Do not expose section addresses to non-CAP_SYSLOG
module: Refactor section attr into bin attribute
kallsyms: Refactor kallsyms_show_value() to take cred
If the genlmsg_put() call in ethnl_default_dumpit() fails, we bail out
without checking if we already have some messages in current skb like we do
with ethnl_default_dump_one() failure later. Therefore if existing messages
almost fill up the buffer so that there is not enough space even for
netlink and genetlink header, we lose all prepared messages and return and
error.
Rather than duplicating the skb->len check, move the genlmsg_put(),
genlmsg_cancel() and genlmsg_end() calls into ethnl_default_dump_one().
This is also more logical as all message composition will be in
ethnl_default_dump_one() and only iteration logic will be left in
ethnl_default_dumpit().
Fixes: 728480f124 ("ethtool: default handlers for GET requests")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When tcf_block_get() fails inside atm_tc_init(),
atm_tc_put() is called to release the qdisc p->link.q.
But the flow->ref prevents it to do so, as the flow->ref
is still zero.
Fix this by moving the p->link.ref initialization before
tcf_block_get().
Fixes: 6529eaba33 ("net: sched: introduce tcf block infractructure")
Reported-and-tested-by: syzbot+d411cff6ab29cc2c311b@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When evaluating access control over kallsyms visibility, credentials at
open() time need to be used, not the "current" creds (though in BPF's
case, this has likely always been the same). Plumb access to associated
file->f_cred down through bpf_dump_raw_ok() and its callers now that
kallsysm_show_value() has been refactored to take struct cred.
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 7105e828c0 ("bpf: allow for correlation of maps and helpers in dump")
Signed-off-by: Kees Cook <keescook@chromium.org>
A scenario has been observed where a 'bc_init' message for a link is not
retransmitted if it fails to be received by the peer. This leads to the
peer never establishing the link fully and it discarding all other data
received on the link. In this scenario the message is lost in transit to
the peer.
The issue is traced to the 'nxt_retr' field of the skb not being
initialised for links that aren't a bc_sndlink. This leads to the
comparison in tipc_link_advance_transmq() that gates whether to attempt
retransmission of a message performing in an undesirable way.
Depending on the relative value of 'jiffies', this comparison:
time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr)
may return true or false given that 'nxt_retr' remains at the
uninitialised value of 0 for non bc_sndlinks.
This is most noticeable shortly after boot when jiffies is initialised
to a high value (to flush out rollover bugs) and we compare a jiffies of,
say, 4294940189 to zero. In that case time_before returns 'true' leading
to the skb not being retransmitted.
The fix is to ensure that all skbs have a valid 'nxt_retr' time set for
them and this is achieved by refactoring the setting of this value into
a central function.
With this fix, transmission losses of 'bc_init' messages do not stall
the link establishment forever because the 'bc_init' message is
retransmitted and the link eventually establishes correctly.
Fixes: 382f598fb6 ("tipc: reduce duplicate packets for unicast traffic")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the tx path of l2tp, l2tp_xmit_skb() calls skb_dst_set() to set
skb's dst. However, it will eventually call inet6_csk_xmit() or
ip_queue_xmit() where skb's dst will be overwritten by:
skb_dst_set_noref(skb, dst);
without releasing the old dst in skb. Then it causes dst/dev refcnt leak:
unregister_netdevice: waiting for eth0 to become free. Usage count = 1
This can be reproduced by simply running:
# modprobe l2tp_eth && modprobe l2tp_ip
# sh ./tools/testing/selftests/net/l2tp.sh
So before going to inet6_csk_xmit() or ip_queue_xmit(), skb's dst
should be dropped. This patch is to fix it by removing skb_dst_set()
from l2tp_xmit_skb() and moving skb_dst_drop() into l2tp_xmit_core().
Fixes: 3557baabf2 ("[L2TP]: PPP over L2TP driver core")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: James Chapman <jchapman@katalix.com>
Tested-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CLC proposal messages of future SMCD versions could be larger than SMCD
V1 CLC proposal messages.
To enable toleration in SMC V1 the receival of CLC proposal messages
is adapted:
* accept larger length values in CLC proposal
* check trailing eye catcher for incoming CLC proposal with V1 length only
* receive the whole CLC proposal even in cases it does not fit into the
V1 buffer
Fixes: e7b7a64a84 ("smc: support variable CLC proposal messages")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The similar smc_ib_devices spinlock has been converted to a mutex.
Protecting the smcd_dev_list by a mutex is possible as well. This
patch converts the smcd_dev_list spinlock to a mutex.
Fixes: c6ba7c9ba4 ("net/smc: add base infrastructure for SMC-D and ISM")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tests showed this BUG:
[572555.252867] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
[572555.252876] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 131031, name: smcapp
[572555.252879] INFO: lockdep is turned off.
[572555.252883] CPU: 1 PID: 131031 Comm: smcapp Tainted: G O 5.7.0-rc3uschi+ #356
[572555.252885] Hardware name: IBM 3906 M03 703 (LPAR)
[572555.252887] Call Trace:
[572555.252896] [<00000000ac364554>] show_stack+0x94/0xe8
[572555.252901] [<00000000aca1f400>] dump_stack+0xa0/0xe0
[572555.252906] [<00000000ac3c8c10>] ___might_sleep+0x260/0x280
[572555.252910] [<00000000acdc0c98>] __mutex_lock+0x48/0x940
[572555.252912] [<00000000acdc15c2>] mutex_lock_nested+0x32/0x40
[572555.252975] [<000003ff801762d0>] mlx5_lag_get_roce_netdev+0x30/0xc0 [mlx5_core]
[572555.252996] [<000003ff801fb3aa>] mlx5_ib_get_netdev+0x3a/0xe0 [mlx5_ib]
[572555.253007] [<000003ff80063848>] smc_pnet_find_roce_resource+0x1d8/0x310 [smc]
[572555.253011] [<000003ff800602f0>] __smc_connect+0x1f0/0x3e0 [smc]
[572555.253015] [<000003ff80060634>] smc_connect+0x154/0x190 [smc]
[572555.253022] [<00000000acbed8d4>] __sys_connect+0x94/0xd0
[572555.253025] [<00000000acbef620>] __s390x_sys_socketcall+0x170/0x360
[572555.253028] [<00000000acdc6800>] system_call+0x298/0x2b8
[572555.253030] INFO: lockdep is turned off.
Function smc_pnet_find_rdma_dev() might be called from
smc_pnet_find_roce_resource(). It holds the smc_ib_devices list
spinlock while calling infiniband op get_netdev(). At least for mlx5
the get_netdev operation wants mutex serialization, which conflicts
with the smc_ib_devices spinlock.
This patch switches the smc_ib_devices spinlock into a mutex to
allow sleeping when calling get_netdev().
Fixes: a4cf0443c4 ("smc: introduce SMC as an IB-client")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wait for pending sends only when smc_switch_conns() found a link to move
the connections to. Do not wait during link freeing, this can lead to
permanent hang situations. And refuse to provide a new tx slot on an
unusable link.
Fixes: c6f02ebeea ("net/smc: switch connections to alternate link")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There might be races in scenarios where both SMC link groups are on the
same system. Prevent that by creating separate wait queues for LLC flows
and messages. Switch to non-interruptable versions of wait_event() and
wake_up() for the llc flow waiter to make sure the waiters get control
sequentially. Fine tune the llc_flow_lock to include the assignment of
the message. Write to system log when an unexpected message was
dropped. And remove an extra indirection and use the existing local
variable lgr in smc_llc_enqueue().
Fixes: 555da9af82 ("net/smc: add event-based llc_flow framework")
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While pipes don't really need sb_writers projection, __kernel_write is an
interface better kept private, and the additional rw_verify_area does not
hurt here.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit e57f61858b ("net: bridge: mcast: fix stale nsrcs pointer in
igmp3/mld2 report handling") introduced a bug in the IPv6 header payload
length check which would potentially lead to rejecting a valid MLD2 Report:
The check needs to take into account the 2 bytes for the "Number of
Sources" field in the "Multicast Address Record" before reading it.
And not the size of a pointer to this field.
Fixes: e57f61858b ("net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling")
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
When tcf_ct_act execute the tcf_lastuse_update should
be update or the used stats never update
filter protocol ip pref 3 flower chain 0
filter protocol ip pref 3 flower chain 0 handle 0x1
eth_type ipv4
dst_ip 1.1.1.1
ip_flags frag/firstfrag
skip_hw
not_in_hw
action order 1: ct zone 1 nat pipe
index 1 ref 1 bind 1 installed 103 sec used 103 sec
Action statistics:
Sent 151500 bytes 101 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
cookie 4519c04dc64a1a295787aab13b6a50fb
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
The RFC 8684 mandates that no-data DATA FIN packets should carry
a DSS with 0 sequence number and data len equal to 1. Currently,
on FIN retransmission we re-use the existing mapping; if the previous
fin transmission was part of a partially acked data packet, we could
end-up writing in the egress packet a non-compliant DSS.
The above will be detected by a "Bad mapping" warning on the receiver
side.
This change addresses the issue explicitly checking for 0 len packet
when adding the DATA_FIN option.
Fixes: 6d0060f600 ("mptcp: Write MPTCP DSS headers to outgoing data packets")
Reported-by: syzbot+42a07faa5923cfaeb9c9@syzkaller.appspotmail.com
Tested-by: Christoph Paasch <cpaasch@apple.com>
Reviewed-by: Christoph Paasch <cpaasch@apple.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv4 ping sockets don't set fl4.fl4_icmp_{type,code}, which leads to
incomplete IPsec ACQUIRE messages being sent to userspace. Currently,
both raw sockets and IPv6 ping sockets set those fields.
Expected output of "ip xfrm monitor":
acquire proto esp
sel src 10.0.2.15/32 dst 8.8.8.8/32 proto icmp type 8 code 0 dev ens4
policy src 10.0.2.15/32 dst 8.8.8.8/32
<snip>
Currently with ping sockets:
acquire proto esp
sel src 10.0.2.15/32 dst 8.8.8.8/32 proto icmp type 0 code 0 dev ens4
policy src 10.0.2.15/32 dst 8.8.8.8/32
<snip>
The Libreswan test suite found this problem after Fedora changed the
value for the sysctl net.ipv4.ping_group_range.
Fixes: c319b4d76b ("net: ipv4: add IPPROTO_ICMP socket kind")
Reported-by: Paul Wouters <pwouters@redhat.com>
Tested-by: Paul Wouters <pwouters@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we clone a socket in sk_clone_lock(), its sk_cgrp_data is
copied, so the cgroup refcnt must be taken too. And, unlike the
sk_alloc() path, sock_update_netprioidx() is not called here.
Therefore, it is safe and necessary to grab the cgroup refcnt
even when cgroup_sk_alloc is disabled.
sk_clone_lock() is in BH context anyway, the in_interrupt()
would terminate this function if called there. And for sk_alloc()
skcd->val is always zero. So it's safe to factor out the code
to make it more readable.
The global variable 'cgroup_sk_alloc_disabled' is used to determine
whether to take these reference counts. It is impossible to make
the reference counting correct unless we save this bit of information
in skcd->val. So, add a new bit there to record whether the socket
has already taken the reference counts. This obviously relies on
kmalloc() to align cgroup pointers to at least 4 bytes,
ARCH_KMALLOC_MINALIGN is certainly larger than that.
This bug seems to be introduced since the beginning, commit
d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
tried to fix it but not compeletely. It seems not easy to trigger until
the recent commit 090e28b229
("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged.
Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reported-by: Daniël Sonck <dsonck92@gmail.com>
Reported-by: Zhang Qiang <qiang.zhang@windriver.com>
Tested-by: Cameron Berkenpas <cam@neo-zeon.de>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Thomas reported a regression with IPv6 and anycast using the following
reproducer:
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding
ip -6 a add fc12::1/16 dev lo
sleep 2
echo "pinging lo"
ping6 -c 2 fc12::
The conversion of addrconf_f6i_alloc to use ip6_route_info_create missed
the use of fib6_is_reject which checks addresses added to the loopback
interface and sets the REJECT flag as needed. Update fib6_is_reject for
loopback checks to handle RTF_ANYCAST addresses.
Fixes: c7a1ce397a ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create")
Reported-by: thomas.gambier@nexedi.com
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Brian reported a crash in IPv6 code when using rpfilter with a setup
running FRR and external nexthop objects. The root cause of the crash
is fib6_select_path setting fib6_nh in the result to NULL because of
an improper check for nexthop objects.
More specifically, rpfilter invokes ip6_route_lookup with flowi6_oif
set causing fib6_select_path to be called with have_oif_match set.
fib6_select_path has early check on have_oif_match and jumps to the
out label which presumes a builtin fib6_nh. This path is invalid for
nexthop objects; for external nexthops fib6_select_path needs to just
return if the fib6_nh has already been set in the result otherwise it
returns after the call to nexthop_path_fib6_result. Update the check
on have_oif_match to not bail on external nexthops.
Update selftests for this problem.
Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Reported-by: Brian Rak <brak@choopa.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Use kvfree() to release vmalloc()'ed areas in ipset, from Eric Dumazet.
2) UAF in nfnetlink_queue from the nf_conntrack_update() path.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There are a couple of places in net/sched/ that check skb->protocol and act
on the value there. However, in the presence of VLAN tags, the value stored
in skb->protocol can be inconsistent based on whether VLAN acceleration is
enabled. The commit quoted in the Fixes tag below fixed the users of
skb->protocol to use a helper that will always see the VLAN ethertype.
However, most of the callers don't actually handle the VLAN ethertype, but
expect to find the IP header type in the protocol field. This means that
things like changing the ECN field, or parsing diffserv values, stops
working if there's a VLAN tag, or if there are multiple nested VLAN
tags (QinQ).
To fix this, change the helper to take an argument that indicates whether
the caller wants to skip the VLAN tags or not. When skipping VLAN tags, we
make sure to skip all of them, so behaviour is consistent even in QinQ
mode.
To make the helper usable from the ECN code, move it to if_vlan.h instead
of pkt_sched.h.
v3:
- Remove empty lines
- Move vlan variable definitions inside loop in skb_protocol()
- Also use skb_protocol() helper in IP{,6}_ECN_decapsulate() and
bpf_skb_ecn_set_ce()
v2:
- Use eth_type_vlan() helper in skb_protocol()
- Also fix code that reads skb->protocol directly
- Change a couple of 'if/else if' statements to switch constructs to avoid
calling the helper twice
Reported-by: Ilya Ponetayev <i.ponetaev@ndmsystems.com>
Fixes: d8b9605d26 ("net: sched: fix skb->protocol use in case of accelerated vlan path")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
leak and a module unloading bug in the /proc/fs/nfsd/clients/ code, and
a compile warning.
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Merge tag 'nfsd-5.8-1' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
"Fixes for a umask bug on exported filesystems lacking ACL support, a
leak and a module unloading bug in the /proc/fs/nfsd/clients/ code,
and a compile warning"
* tag 'nfsd-5.8-1' of git://linux-nfs.org/~bfields/linux:
SUNRPC: Add missing definition of ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
nfsd: fix nfsdfs inode reference count leak
nfsd4: fix nfsdfs reference count loop
nfsd: apply umask on fs without ACL support
This essentially reverts commit 7212303268 ("tcp: md5: reject TCP_MD5SIG
or TCP_MD5SIG_EXT on established sockets")
Mathieu reported that many vendors BGP implementations can
actually switch TCP MD5 on established flows.
Quoting Mathieu :
Here is a list of a few network vendors along with their behavior
with respect to TCP MD5:
- Cisco: Allows for password to be changed, but within the hold-down
timer (~180 seconds).
- Juniper: When password is initially set on active connection it will
reset, but after that any subsequent password changes no network
resets.
- Nokia: No notes on if they flap the tcp connection or not.
- Ericsson/RedBack: Allows for 2 password (old/new) to co-exist until
both sides are ok with new passwords.
- Meta-Switch: Expects the password to be set before a connection is
attempted, but no further info on whether they reset the TCP
connection on a change.
- Avaya: Disable the neighbor, then set password, then re-enable.
- Zebos: Would normally allow the change when socket connected.
We can revert my prior change because commit 9424e2e7ad ("tcp: md5: fix potential
overestimation of TCP option space") removed the leak of 4 kernel bytes to
the wire that was the main reason for my patch.
While doing my investigations, I found a bug when a MD5 key is changed, leading
to these commits that stable teams want to consider before backporting this revert :
Commit 6a2febec33 ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()")
Commit e6ced831ef ("tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriers")
Fixes: 7212303268 "tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets"
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whenever tcp_try_rmem_schedule() returns an error, we are under
trouble and should make sure to wakeup readers so that they
can drain socket queues and eventually make room.
Fixes: 03f45c883c ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When no full socket is available, skbs are sent over a per-netns
control socket. Its sk_mark is temporarily adjusted to match that
of the real (request or timewait) socket or to reflect an incoming
skb, so that the outgoing skb inherits this in __ip_make_skb.
Introduction of the socket cookie mark field broke this. Now the
skb is set through the cookie and cork:
<caller> # init sockc.mark from sk_mark or cmsg
ip_append_data
ip_setup_cork # convert sockc.mark to cork mark
ip_push_pending_frames
ip_finish_skb
__ip_make_skb # set skb->mark to cork mark
But I missed these special control sockets. Update all callers of
__ip(6)_make_skb that were originally missed.
For IPv6, the same two icmp(v6) paths are affected. The third
case is not, as commit 92e55f412c ("tcp: don't annotate
mark on control socket from tcp_v6_send_response()") replaced
the ctl_sk->sk_mark with passing the mark field directly as a
function argument. That commit predates the commit that
introduced the bug.
Fixes: c6af0c227a ("ip: support SO_MARK cmsg")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reported-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whenever cookie_init_timestamp() has been used to encode
ECN,SACK,WSCALE options, we can not remove the TS option in the SYNACK.
Otherwise, tcp_synack_options() will still advertize options like WSCALE
that we can not deduce later when receiving the packet from the client
to complete 3WHS.
Note that modern linux TCP stacks wont use MD5+TS+SACK in a SYN packet,
but we can not know for sure that all TCP stacks have the same logic.
Before the fix a tcpdump would exhibit this wrong exchange :
10:12:15.464591 IP C > S: Flags [S], seq 4202415601, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 456965269 ecr 0,nop,wscale 8], length 0
10:12:15.464602 IP S > C: Flags [S.], seq 253516766, ack 4202415602, win 65535, options [nop,nop,md5 valid,mss 1400,nop,nop,sackOK,nop,wscale 8], length 0
10:12:15.464611 IP C > S: Flags [.], ack 1, win 256, options [nop,nop,md5 valid], length 0
10:12:15.464678 IP C > S: Flags [P.], seq 1:13, ack 1, win 256, options [nop,nop,md5 valid], length 12
10:12:15.464685 IP S > C: Flags [.], ack 13, win 65535, options [nop,nop,md5 valid], length 0
After this patch the exchange looks saner :
11:59:59.882990 IP C > S: Flags [S], seq 517075944, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 1751508483 ecr 0,nop,wscale 8], length 0
11:59:59.883002 IP S > C: Flags [S.], seq 1902939253, ack 517075945, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 1751508479 ecr 1751508483,nop,wscale 8], length 0
11:59:59.883012 IP C > S: Flags [.], ack 1, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508479], length 0
11:59:59.883114 IP C > S: Flags [P.], seq 1:13, ack 1, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508479], length 12
11:59:59.883122 IP S > C: Flags [.], ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508483], length 0
11:59:59.883152 IP S > C: Flags [P.], seq 1:13, ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508484 ecr 1751508483], length 12
11:59:59.883170 IP C > S: Flags [.], ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508484 ecr 1751508484], length 0
Of course, no SACK block will ever be added later, but nothing should break.
Technically, we could remove the 4 nops included in MD5+TS options,
but again some stacks could break seeing not conventional alignment.
Fixes: 4957faade1 ("TCPCT part 1g: Responder Cookie => Initiator")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Karsten Graul