From: Zhu Yanjun <yanjun.zhu@linux.dev>
Date: Tue, 5 Jul 2022 18:54:14 -0400
Subject: RDMA/rxe: Fix BUG: KASAN: null-ptr-deref in rxe_qp_do_cleanup
Patch-mainline: v6.0-rc1
Git-commit: 37da51efe6eaa0560f46803c8c436a48a2084da7
References: jsc#PED-1111
The function rxe_create_qp calls rxe_qp_from_init. If some error
occurs, the error handler of function rxe_qp_from_init will set
both scq and rcq to NULL.
Then rxe_create_qp calls rxe_put to handle qp. In the end,
rxe_qp_do_cleanup is called by rxe_put. rxe_qp_do_cleanup directly
accesses scq and rcq before checking them. This will cause
null-ptr-deref error.
The call graph is as below:
rxe_create_qp {
...
rxe_qp_from_init {
...
err1:
...
qp->rcq = NULL; <---rcq is set to NULL
qp->scq = NULL; <---scq is set to NULL
...
}
qp_init:
rxe_put{
...
rxe_qp_do_cleanup {
...
atomic_dec(&qp->scq->num_wq); <--- scq is accessed
...
atomic_dec(&qp->rcq->num_wq); <--- rcq is accessed
}
}
Fixes: 4703b4f0d94a ("RDMA/rxe: Enforce IBA C11-17")
Link: https://lore.kernel.org/r/20220705225414.315478-1-yanjun.zhu@linux.dev
Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Bob Pearson <rpearsonhpe@gmail.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/infiniband/sw/rxe/rxe_qp.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
--- a/drivers/infiniband/sw/rxe/rxe_qp.c
+++ b/drivers/infiniband/sw/rxe/rxe_qp.c
@@ -802,13 +802,15 @@ static void rxe_qp_do_cleanup(struct wor
if (qp->rq.queue)
rxe_queue_cleanup(qp->rq.queue);
- atomic_dec(&qp->scq->num_wq);
- if (qp->scq)
+ if (qp->scq) {
+ atomic_dec(&qp->scq->num_wq);
rxe_put(qp->scq);
+ }
- atomic_dec(&qp->rcq->num_wq);
- if (qp->rcq)
+ if (qp->rcq) {
+ atomic_dec(&qp->rcq->num_wq);
rxe_put(qp->rcq);
+ }
if (qp->pd)
rxe_put(qp->pd);