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| author | Cheng Xu <chengyou@linux.alibaba.com> | 2022-04-24 16:01:03 +0800 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2022-05-04 20:59:54 -0300 |
| commit | ef91271c65c12d36e4c2b61c61d4849fb6d11aa0 (patch) | |
| tree | 2995445a2fffbfb79041d7329724d094c2e2ef95 /drivers | |
| parent | 1c9043ae0667a43bd87beeebbdd4bed674713629 (diff) | |
| download | lwn-ef91271c65c12d36e4c2b61c61d4849fb6d11aa0.tar.gz lwn-ef91271c65c12d36e4c2b61c61d4849fb6d11aa0.zip | |
RDMA/siw: Fix a condition race issue in MPA request processing
The calling of siw_cm_upcall and detaching new_cep with its listen_cep
should be atomistic semantics. Otherwise siw_reject may be called in a
temporary state, e,g, siw_cm_upcall is called but the new_cep->listen_cep
has not being cleared.
This fixes a WARN:
WARNING: CPU: 7 PID: 201 at drivers/infiniband/sw/siw/siw_cm.c:255 siw_cep_put+0x125/0x130 [siw]
CPU: 2 PID: 201 Comm: kworker/u16:22 Kdump: loaded Tainted: G E 5.17.0-rc7 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: iw_cm_wq cm_work_handler [iw_cm]
RIP: 0010:siw_cep_put+0x125/0x130 [siw]
Call Trace:
<TASK>
siw_reject+0xac/0x180 [siw]
iw_cm_reject+0x68/0xc0 [iw_cm]
cm_work_handler+0x59d/0xe20 [iw_cm]
process_one_work+0x1e2/0x3b0
worker_thread+0x50/0x3a0
? rescuer_thread+0x390/0x390
kthread+0xe5/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
Fixes: 6c52fdc244b5 ("rdma/siw: connection management")
Link: https://lore.kernel.org/r/d528d83466c44687f3872eadcb8c184528b2e2d4.1650526554.git.chengyou@linux.alibaba.com
Reported-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/infiniband/sw/siw/siw_cm.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c index 7acdd3c3a599..17f34d584cd9 100644 --- a/drivers/infiniband/sw/siw/siw_cm.c +++ b/drivers/infiniband/sw/siw/siw_cm.c @@ -968,14 +968,15 @@ static void siw_accept_newconn(struct siw_cep *cep) siw_cep_set_inuse(new_cep); rv = siw_proc_mpareq(new_cep); - siw_cep_set_free(new_cep); - if (rv != -EAGAIN) { siw_cep_put(cep); new_cep->listen_cep = NULL; - if (rv) + if (rv) { + siw_cep_set_free(new_cep); goto error; + } } + siw_cep_set_free(new_cep); } return; |