[tcp] Fix potential NULL pointer dereference

Detected using Valgrind. Signed-off-by: Michael Brown <mcb30@ipxe.org>
ipxe · May 8, 2012 · 52dd4ba · 52dd4ba
1 parent e844297
commit 52dd4ba
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/net/tcp.c b/src/net/tcp.c
@@ -1143,7 +1143,7 @@ static int tcp_rx ( struct io_buffer *iobuf,
 	flags = tcphdr->flags;
 	tcp_rx_opts ( tcp, ( ( ( void * ) tcphdr ) + sizeof ( *tcphdr ) ),
 		      ( hlen - sizeof ( *tcphdr ) ), &options );
-	if ( options.tsopt )
+	if ( tcp && options.tsopt )
 		tcp->ts_val = ntohl ( options.tsopt->tsval );
 	iob_pull ( iobuf, hlen );
 	len = iob_len ( iobuf );