net/bnxt: add null check for mark table

[ upstream commit 8a553bd ]

During the port start, driver ignores mark table allocation failure.
This could cause a segfault due to NULL pointer dereference in
bnxt_set_mark_in_mbuf(). Fix this by checking the pointer validity
before accessing it.

Fixes: b87abb2 ("net/bnxt: support marking packet")

Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>

drivers/net/bnxt/bnxt_rxr.c

@@ -824,6 +824,9 @@ void bnxt_set_mark_in_mbuf(struct bnxt *bp,
 {
 	uint32_t cfa_code = 0;
 
+	if (unlikely(bp->mark_table == NULL))
+		return;
+
 	cfa_code = rte_le_to_cpu_16(rxcmp1->cfa_code);
 	if (!cfa_code)
 		return;