Add bounds checking.

diff --git a/print-aodv.c b/print-aodv.c
index b1539a9abb5815d58a0ea09b76b355de5a4b7a15..c5f662237448982a8b58701a18c6c5285728a738 100644 (file)
--- a/print-aodv.c
+++ b/print-aodv.c
@@ -32,7 +32,7 @@
 
 #ifndef lint
 static const char rcsid[] _U_ =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-aodv.c,v 1.10 2003-11-16 09:36:12 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-aodv.c,v 1.11 2004-03-24 00:30:19 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -143,20 +143,30 @@ aodv_rrep(const union aodv *ap, const u_char *dat, u_int length)
 }
 
 static void
-aodv_rerr(const union aodv *ap, u_int length)
+aodv_rerr(const union aodv *ap, const u_char *dat, u_int length)
 {
+       u_int i;
        const struct rerr_unreach *dp = NULL;
-       int i, j, n, trunc;
+       int n, trunc;
 
-       i = length - offsetof(struct aodv_rerr, r);
-       j = sizeof(ap->rerr.r.dest[0]);
+       if (snapend < dat) {
+               printf(" [|aodv]");
+               return;
+       }
+       i = min(length, (u_int)(snapend - dat));
+       if (i < offsetof(struct aodv_rerr, r)) {
+               printf(" [|rerr]");
+               return;
+       }
+       i -= offsetof(struct aodv_rerr, r);
        dp = &ap->rerr.r.dest[0];
-       n = ap->rerr.rerr_dc * j;
+       n = ap->rerr.rerr_dc * sizeof(ap->rerr.r.dest[0]);
        printf(" rerr %s [items %u] [%u]:",
            ap->rerr.rerr_flags & RERR_NODELETE ? "[D]" : "",
            ap->rerr.rerr_dc, length);
-       trunc = n - (i/j);
-       for (; i -= j >= 0; ++dp) {
+       trunc = n - (i/sizeof(ap->rerr.r.dest[0]));
+       for (; i >= sizeof(ap->rerr.r.dest[0]);
+           ++dp, i -= sizeof(ap->rerr.r.dest[0])) {
                printf(" {%s}(%ld)", ipaddr_string(&dp->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp->u_ds));
        }
@@ -416,7 +426,7 @@ aodv_print(const u_char *dat, u_int length, int is_ip6)
                if (is_ip6)
                        aodv_v6_rerr(ap, length);
                else
-                       aodv_rerr(ap, length);
+                       aodv_rerr(ap, dat, length);
                break;
 
        case AODV_RREP_ACK: