X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/9169e4e1949c3fa879f0a2f98cfbd8c444743c27..e69972a8ef1ddbf73924e42f76f53a1f9d0aab0a:/print-ip.c?ds=sidebyside

diff --git a/print-ip.c b/print-ip.c
index 7cec6404..23ba99c9 100644
--- a/print-ip.c
+++ b/print-ip.c
@@ -377,7 +377,10 @@ ip_print(netdissect_options *ndo,
 	/*
 	 * Cut off the snapshot length to the end of the IP payload.
 	 */
-	nd_push_snapend(ndo, bp + len);
+	if (!nd_push_snaplen(ndo, bp, len)) {
+		(*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
+			"%s: can't push snaplen on buffer stack", __func__);
+	}
 
 	len -= hlen;
 
@@ -471,8 +474,18 @@ ip_print(netdissect_options *ndo,
 				     GET_IPADDR_STRING(ip->ip_src),
 				     GET_IPADDR_STRING(ip->ip_dst));
 		}
+		/*
+		 * Do a bounds check before calling ip_demux_print().
+		 * At least the header data is required.
+		 */
+		if (!ND_TTEST_LEN((const u_char *)ip, hlen)) {
+			ND_PRINT(" [remaining caplen(%u) < header length(%u)]",
+				 ND_BYTES_AVAILABLE_AFTER((const u_char *)ip),
+				 hlen);
+			nd_trunc_longjmp(ndo);
+		}
 		ip_demux_print(ndo, (const u_char *)ip + hlen, len, 4,
-		    off & IP_MF, GET_U_1(ip->ip_ttl), nh, bp);
+			       off & IP_MF, GET_U_1(ip->ip_ttl), nh, bp);
 	} else {
 		/*
 		 * Ultra quiet now means that all this stuff should be