[dpdk-dev] [PATCH v2 1/2] net: check that seg is valid before dereference

[Chas Williams <3chas3@gmail.com>]

If the overall pkt_len and segment lengths are out of agreement,
it is possible for the seg to be NULL after the loop. Add assert
to check this condition in debug builds. Otherwise, return failure.

Fixes: c442fed81bb9 ("net: add function to calculate checksum in mbuf")

Signed-off-by: Chas Williams <3chas3@gmail.com>
---
 lib/librte_net/rte_ip.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index fcd1eb342..b2bb5d7b9 100644
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -225,6 +225,9 @@ rte_raw_cksum_mbuf(const struct rte_mbuf *m, uint32_t off, uint32_t len,
 			break;
 		off -= seglen;
 	}
+	RTE_ASSERT(seg != NULL);
+	if (seg == NULL)
+		return -1;
 	seglen -= off;
 	buf = rte_pktmbuf_mtod_offset(seg, const char *, off);
 	if (seglen >= len) {
-- 
2.26.2