Module Name: src
Committed By: bouyer
Date: Sat Mar 9 18:25:30 UTC 2024
Modified Files:
src/external/bsd/tcpdump/dist [netbsd-10]: print-ppp.c
Log Message:
Apply patch, requested by martin in ticket #623:
external/bsd/tcpdump/dist/print-ppp.c patch
Apply upstream commit 32027e199368dad9508965aae8cd8de5b6ab5231
to fix CVE-2020-803:
PPP: When un-escaping, don't allocate a too-large buffer.
The buffer should be big enough to hold the captured data, but it
doesn't need to be big enough to hold the entire on-the-network packet,
if we haven't captured all of it.
fixes PR 57586
To generate a diff of this commit:
cvs rdiff -u -r1.9 -r1.9.14.1 src/external/bsd/tcpdump/dist/print-ppp.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/bsd/tcpdump/dist/print-ppp.c
diff -u src/external/bsd/tcpdump/dist/print-ppp.c:1.9 src/external/bsd/tcpdump/dist/print-ppp.c:1.9.14.1
--- src/external/bsd/tcpdump/dist/print-ppp.c:1.9 Fri Sep 8 14:01:13 2017
+++ src/external/bsd/tcpdump/dist/print-ppp.c Sat Mar 9 18:25:30 2024
@@ -33,7 +33,7 @@
#include <sys/cdefs.h>
#ifndef lint
-__RCSID("$NetBSD: print-ppp.c,v 1.9 2017/09/08 14:01:13 christos Exp $");
+__RCSID("$NetBSD: print-ppp.c,v 1.9.14.1 2024/03/09 18:25:30 bouyer Exp $");
#endif
#ifdef HAVE_CONFIG_H
@@ -1372,19 +1372,29 @@ trunc:
return 0;
}
+/*
+ * Un-escape RFC 1662 PPP in HDLC-like framing, with octet escapes.
+ * The length argument is the on-the-wire length, not the captured
+ * length; we can only un-escape the captured part.
+ */
static void
ppp_hdlc(netdissect_options *ndo,
const u_char *p, int length)
{
+ u_int caplen = ndo->ndo_snapend - p;
u_char *b, *t, c;
const u_char *s;
- int i, proto;
+ u_int i;
+ int proto;
const void *se;
+ if (caplen == 0)
+ return;
+
if (length <= 0)
return;
- b = (u_char *)malloc(length);
+ b = (u_char *)malloc(caplen);
if (b == NULL)
return;
@@ -1393,10 +1403,10 @@ ppp_hdlc(netdissect_options *ndo,
* Do this so that we dont overwrite the original packet
* contents.
*/
- for (s = p, t = b, i = length; i > 0 && ND_TTEST(*s); i--) {
+ for (s = p, t = b, i = caplen; i != 0; i--) {
c = *s++;
if (c == 0x7d) {
- if (i <= 1 || !ND_TTEST(*s))
+ if (i <= 1)
break;
i--;
c = *s++ ^ 0x20;
