Fix rfcnb library potential NULL pointer dereference

Malformed RFCNB packet may lead to crash.

 Detected by Coverity Scan. Issue 740355.

diff --git a/lib/rfcnb/rfcnb-io.c b/lib/rfcnb/rfcnb-io.c
index fea3b2829a12b0233dbf6edb53cdcc0ad8faee50..f628f1b3f5b849eca67d74e7c5ad527fb46762b1 100644 (file)
--- a/lib/rfcnb/rfcnb-io.c
+++ b/lib/rfcnb/rfcnb-io.c
@@ -382,7 +382,7 @@ RFCNB_Get_Pkt(struct RFCNB_Con *con, struct RFCNB_Pkt *pkt, int len)
         offset = RFCNB_Pkt_Hdr_Len;     /* Otherwise skip the header       */
     }
 
-    frag_len = pkt_frag->len;
+    frag_len = (pkt_frag ? pkt_frag->len : 0);
 
     if (more <= frag_len)       /* If len left to get less than frag space */
         this_len = more;        /* Get the rest ...                        */