net/bnxt: avoid null pointer dereference

Commit "bd0a14c99f65" enables the creation of a dedicated completion
ring for asynchronous event handling instead of handling these
events on a receive completion ring on non Stingray Platforms.

This causes a segfault due to NULL pointer dereference in
bnxt_alloc_async_cp_ring() on stingray. Fix this by checking the
pointer validity before accessing it.

Fixes: bd0a14c99f65 ("net/bnxt: use dedicated CPR for async events")
Cc: stable@dpdk.org
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Rahul Gupta <rahul.gupta@broadcom.com>
Reviewed-by: Lance Richardson <lance.richardson@broadcom.com>

diff --git a/drivers/net/bnxt/bnxt_ring.c b/drivers/net/bnxt/bnxt_ring.c
index 2f57e03..ec17783 100644 (file)
--- a/drivers/net/bnxt/bnxt_ring.c
+++ b/drivers/net/bnxt/bnxt_ring.c
@@ -694,13 +694,15 @@ err_out:
 int bnxt_alloc_async_cp_ring(struct bnxt *bp)
 {
        struct bnxt_cp_ring_info *cpr = bp->async_cp_ring;
-       struct bnxt_ring *cp_ring = cpr->cp_ring_struct;
+       struct bnxt_ring *cp_ring;
        uint8_t ring_type;
        int rc;
 
-       if (BNXT_NUM_ASYNC_CPR(bp) == 0)
+       if (BNXT_NUM_ASYNC_CPR(bp) == 0 || cpr == NULL)
                return 0;
 
+       cp_ring = cpr->cp_ring_struct;
+
        if (BNXT_HAS_NQ(bp))
                ring_type = HWRM_RING_ALLOC_INPUT_RING_TYPE_NQ;
        else