Do more length checking. From OpenBSD.

diff --git a/print-sl.c b/print-sl.c
index fb6a59ceb586992318d18af3762d1d0a665994df..bd410ce21a28ff49e0128c4022645cae73e5fa07 100644 (file)
--- a/print-sl.c
+++ b/print-sl.c
@@ -62,7 +62,7 @@ sl_if_print(netdissect_options *ndo,
        register u_int length = h->len;
        register const struct ip *ip;
 
-       if (caplen < SLIP_HDRLEN) {
+       if (caplen < SLIP_HDRLEN || length < SLIP_HDRLEN) {
                ND_PRINT((ndo, "%s", tstr));
                return (caplen);
        }