diff options
| author |   Guoqing Jiang <guoqing.jiang@linux.dev> | 2026-08-27 20:55:53 +0800 |
|---|---|---|
| committer |   Leon Romanovsky <leon@kernel.org> | 2026-09-01 03:33:04 -0400 |
| commit | 32cd87f54dd1070020e664ccb0312a9f0fea79b4 (patch) | |
| tree | b029d052ad67f9896848e2501053e7610eff72f4 | |
| parent | Linux 7.3-rc1 (diff) | |
RDMA/siw: Clear association under lock if siw_qp_modify fails in siw_accept
We need to clear cep before release state_lock as siw_qp_llp_close and
siw_qp_modify->siw_qp_llp_close did.
Otherwise if siw_qp_modify() fails in siw_accept(), the QP's state_lock
is released before the error path cleanup. A concurrent ibv_modify_qp()
transitioning the QP to ERROR can race in this window:
siw_accept() ibv_modify_qp(ERROR)
---------------------- ----------------------
siw_qp_modify() fails
up_write(&qp->state_lock)
down_write(&qp->state_lock)
nextstate_from_idle():
if (qp->cep)
siw_cep_put(qp->cep) <- frees cep
qp->cep = NULL
goto error
cep->qp = NULL <- UAF
Clear qp->cep and drop the association reference taken by siw_cep_get(),
all under the write lock held from the initial down_write(&qp->state_lock).
Thread B therefore sees qp->cep == NULL, skips its own put, and cannot free
the cep before siw_accept() is done with it.
Fixes: 6c52fdc244b5 ("rdma/siw: connection management")
Reported-by: Shuangpeng Bai <shuangpeng.kernel@gmail.com>
Link: https://lore.kernel.org/linux-rdma/d6fbe475-a5c2-f975-99b0-a0bd6b6d10e8@linux.dev/T/#m5876c1ff2de8686a9a1173b8f1aa0ff5363a785c
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://patch.msgid.link/20260827125553.12831-1-guoqing.jiang@linux.dev
Acked-by: Bernard Metzler <bernard.metzler@linux.dev>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
| -rw-r--r-- | drivers/infiniband/sw/siw/siw_cm.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c index 0245b25e7271..ed49818793dd 100644 --- a/drivers/infiniband/sw/siw/siw_cm.c +++ b/drivers/infiniband/sw/siw/siw_cm.c @@ -1719,9 +1719,12 @@ int siw_accept(struct iw_cm_id *id, struct iw_cm_conn_param *params) SIW_QP_ATTR_STATE | SIW_QP_ATTR_LLP_HANDLE | SIW_QP_ATTR_ORD | SIW_QP_ATTR_IRD | SIW_QP_ATTR_MPA); + if (rv) { + qp->cep = NULL; + siw_cep_put(cep); + goto error_unlock; + } up_write(&qp->state_lock); - if (rv) - goto error; siw_dbg_cep(cep, "[QP %u]: send mpa reply, %d byte pdata\n", qp_id(qp), params->private_data_len); |