[PATCH 2/3] tcp: Avoid false (but convoluted) positive Coverity CWE-476 warning

[Stefano Brivio <sbrivio@redhat.com>]

If there are no TCP options in the header, tcp_tap_handler() will
pass the corresponding pointer, fetched via packet_get(), as NULL to
tcp_conn_from_sock_finish(), which in turn indirectly calls
tcp_opt_get().

If there are no options, tcp_opt_get() will stop right away because
the option length is indicated as zero. However, if the logic is
complicated enough to follow for static checkers, adding an explicit
check against NULL in tcp_opt_get() is probably a good idea.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 tcp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tcp.c b/tcp.c
index 41210a3..561064e 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1114,7 +1114,7 @@ static int tcp_opt_get(const char *opts, size_t len, uint8_t type_find,
 {
 	uint8_t type, optlen;
 
-	if (!len)
+	if (!opts || !len)
 		return -1;
 
 	for (; len >= 2; opts += optlen, len -= optlen) {
-- 
@@ -1114,7 +1114,7 @@ static int tcp_opt_get(const char *opts, size_t len, uint8_t type_find,
 {
 	uint8_t type, optlen;
 
-	if (!len)
+	if (!opts || !len)
 		return -1;
 
 	for (; len >= 2; opts += optlen, len -= optlen) {
-- 
2.39.1