commit 491f3cbf582e1101ba965144151ea7e6c6c55820
author itojun <itojun> Wed May 10 05:11:27 2000 +0000
committer itojun <itojun> Wed May 10 05:11:27 2000 +0000
tree 762b27df57fe6a89b681aec2558fd7c9e11a8d7b
parent 7fd1be1520c42204a6c7ec62ba34b1dd7b0884bb

correct handling of truncated IPv4 option.

print-ip.c

diff --git a/print-ip.c b/print-ip.c
index 09ae810..0d86de5 100644
--- a/print-ip.c
+++ b/print-ip.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.81 2000-05-01 17:35:45 fenner Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.82 2000-05-10 05:11:27 itojun Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -299,7 +299,15 @@
 	for (; length > 0; cp += len, length -= len) {
 		int tt = *cp;
 
-		len = (tt == IPOPT_NOP || tt == IPOPT_EOL) ? 1 : cp[1];
+		if (tt == IPOPT_NOP || tt == IPOPT_EOL)
+			len = 1;
+		else {
+			if (&cp[1] >= snapend) {
+				printf("[|ip]");
+				return;
+			}
+			len = cp[1];
+		}
 		if (len <= 0) {
 			printf("[|ip op len %d]", len);
 			return;