RDMA/rxe: Fix unsafe drain work queue code

If create_qp does not fully succeed it is possible for qp cleanup
code to attempt to drain the send or recv work queues before the
queues have been created causing a seg fault. This patch checks
to see if the queues exist before attempting to drain them.

Link: https://lore.kernel.org/r/20230620135519.9365-3-rpearsonhpe@gmail.com
Reported-by: syzbot+2da1965168e7dbcba136@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-rdma/00000000000012d89205fe7cfe00@google.com/raw
Fixes: 49dc9c1f0c7e ("RDMA/rxe: Cleanup reset state handling in rxe_resp.c")
Fixes: fbdeb828a21f ("RDMA/rxe: Cleanup error state handling in rxe_comp.c")
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/sw/rxe/rxe_comp.c b/drivers/infiniband/sw/rxe/rxe_comp.c
index 5111735..d0bdc2d 100644 (file)
--- a/drivers/infiniband/sw/rxe/rxe_comp.c
+++ b/drivers/infiniband/sw/rxe/rxe_comp.c
@@ -597,6 +597,10 @@ static void flush_send_queue(struct rxe_qp *qp, bool notify)
        struct rxe_queue *q = qp->sq.queue;
        int err;
 
+       /* send queue never got created. nothing to do. */
+       if (!qp->sq.queue)
+               return;
+
        while ((wqe = queue_head(q, q->type))) {
                if (notify) {
                        err = flush_send_wqe(qp, wqe);

diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
index 64c64f5..da470a9 100644 (file)
--- a/drivers/infiniband/sw/rxe/rxe_resp.c
+++ b/drivers/infiniband/sw/rxe/rxe_resp.c
@@ -1469,6 +1469,10 @@ static void flush_recv_queue(struct rxe_qp *qp, bool notify)
                return;
        }
 
+       /* recv queue not created. nothing to do. */
+       if (!qp->rq.queue)
+               return;
+
        while ((wqe = queue_head(q, q->type))) {
                if (notify) {
                        err = flush_recv_wqe(qp, wqe);