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| author | Guangguan Wang <guangguan.wang@linux.alibaba.com> | 2024-12-11 17:21:16 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-27 13:58:47 +0100 |
| commit | 2627c3e8646932dfc7b9722c88c2e1ffcf7a9fb2 (patch) | |
| tree | 24141948485235dd51efbffc13a6c5976f5452fd /net | |
| parent | 06518a75de0ac4f2738f239c37f76b2ced67eaa3 (diff) | |
| download | linux-2627c3e8646932dfc7b9722c88c2e1ffcf7a9fb2.tar.gz linux-2627c3e8646932dfc7b9722c88c2e1ffcf7a9fb2.tar.bz2 linux-2627c3e8646932dfc7b9722c88c2e1ffcf7a9fb2.zip | |
net/smc: protect link down work from execute after lgr freed
[ Upstream commit 2b33eb8f1b3e8c2f87cfdbc8cc117f6bdfabc6ec ]
link down work may be scheduled before lgr freed but execute
after lgr freed, which may result in crash. So it is need to
hold a reference before shedule link down work, and put the
reference after work executed or canceled.
The relevant crash call stack as follows:
list_del corruption. prev->next should be ffffb638c9c0fe20,
but was 0000000000000000
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:51!
invalid opcode: 0000 [#1] SMP NOPTI
CPU: 6 PID: 978112 Comm: kworker/6:119 Kdump: loaded Tainted: G #1
Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 2221b89 04/01/2014
Workqueue: events smc_link_down_work [smc]
RIP: 0010:__list_del_entry_valid.cold+0x31/0x47
RSP: 0018:ffffb638c9c0fdd8 EFLAGS: 00010086
RAX: 0000000000000054 RBX: ffff942fb75e5128 RCX: 0000000000000000
RDX: ffff943520930aa0 RSI: ffff94352091fc80 RDI: ffff94352091fc80
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffb638c9c0fc38
R10: ffffb638c9c0fc30 R11: ffffffffa015eb28 R12: 0000000000000002
R13: ffffb638c9c0fe20 R14: 0000000000000001 R15: ffff942f9cd051c0
FS: 0000000000000000(0000) GS:ffff943520900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f25214000 CR3: 000000025fbae004 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
rwsem_down_write_slowpath+0x17e/0x470
smc_link_down_work+0x3c/0x60 [smc]
process_one_work+0x1ac/0x350
worker_thread+0x49/0x2f0
? rescuer_thread+0x360/0x360
kthread+0x118/0x140
? __kthread_bind_mask+0x60/0x60
ret_from_fork+0x1f/0x30
Fixes: 541afa10c126 ("net/smc: add smcr_port_err() and smcr_link_down() processing")
Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/smc/smc_core.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 3d5c542cd231..3c626c014d1d 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -1767,7 +1767,9 @@ void smcr_link_down_cond_sched(struct smc_link *lnk) { if (smc_link_downing(&lnk->state)) { trace_smcr_link_down(lnk, __builtin_return_address(0)); - schedule_work(&lnk->link_down_wrk); + smcr_link_hold(lnk); /* smcr_link_put in link_down_wrk */ + if (!schedule_work(&lnk->link_down_wrk)) + smcr_link_put(lnk); } } @@ -1799,11 +1801,14 @@ static void smc_link_down_work(struct work_struct *work) struct smc_link_group *lgr = link->lgr; if (list_empty(&lgr->list)) - return; + goto out; wake_up_all(&lgr->llc_msg_waiter); down_write(&lgr->llc_conf_mutex); smcr_link_down(link); up_write(&lgr->llc_conf_mutex); + +out: + smcr_link_put(link); /* smcr_link_hold by schedulers of link_down_work */ } static int smc_vlan_by_tcpsk_walk(struct net_device *lower_dev, |