| From 0f95d441e4b5d7512cc5c326c8668a120e048eda Mon Sep 17 00:00:00 2001 |
| From: Guy Harris <guy@alum.mit.edu> |
| Date: Wed, 22 Oct 2014 12:31:21 -0700 |
| Subject: [PATCH] Do bounds checking when unescaping PPP. |
| |
| Clean up a const issue while we're at it. |
| |
| Upstream commit 0f95d441e4b5d. |
| |
| Signed-off-by: Baruch Siach <baruch@tkos.co.il> |
| --- |
| print-ppp.c | 16 ++++++++-------- |
| 1 file changed, 8 insertions(+), 8 deletions(-) |
| |
| diff --git a/print-ppp.c b/print-ppp.c |
| index 8e098f05a953..9a983e6179cd 100644 |
| --- a/print-ppp.c |
| +++ b/print-ppp.c |
| @@ -1351,14 +1351,15 @@ static void |
| ppp_hdlc(netdissect_options *ndo, |
| const u_char *p, int length) |
| { |
| - u_char *b, *s, *t, c; |
| + u_char *b, *t, c; |
| + const u_char *s; |
| int i, proto; |
| const void *se; |
| |
| if (length <= 0) |
| return; |
| |
| - b = (uint8_t *)malloc(length); |
| + b = (u_char *)malloc(length); |
| if (b == NULL) |
| return; |
| |
| @@ -1367,14 +1368,13 @@ ppp_hdlc(netdissect_options *ndo, |
| * Do this so that we dont overwrite the original packet |
| * contents. |
| */ |
| - for (s = (u_char *)p, t = b, i = length; i > 0; i--) { |
| + for (s = p, t = b, i = length; i > 0 && ND_TTEST(*s); i--) { |
| c = *s++; |
| if (c == 0x7d) { |
| - if (i > 1) { |
| - i--; |
| - c = *s++ ^ 0x20; |
| - } else |
| - continue; |
| + if (i <= 1 || !ND_TTEST(*s)) |
| + break; |
| + i--; |
| + c = *s++ ^ 0x20; |
| } |
| *t++ = c; |
| } |
| -- |
| 2.1.3 |
| |