[3.13.y.z extended stable] Patch "lzo: properly check for overruns" has been added to staging queue
Kamal Mostafa
kamal at canonical.com
Tue Jul 15 21:29:56 UTC 2014
This is a note to let you know that I have just added a patch titled
lzo: properly check for overruns
to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue
This patch is scheduled to be released in version 3.13.11.5.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
------
>From 4d8abfc21c7144267acfefb166c06e5c12424b15 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Date: Fri, 20 Jun 2014 22:00:53 -0700
Subject: lzo: properly check for overruns
commit 206a81c18401c0cde6e579164f752c4b147324ce upstream.
The lzo decompressor can, if given some really crazy data, possibly
overrun some variable types. Modify the checking logic to properly
detect overruns before they happen.
Reported-by: "Don A. Bailey" <donb at securitymouse.com>
Tested-by: "Don A. Bailey" <donb at securitymouse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
lib/lzo/lzo1x_decompress_safe.c | 62 +++++++++++++++++++++++++++--------------
1 file changed, 41 insertions(+), 21 deletions(-)
diff --git a/lib/lzo/lzo1x_decompress_safe.c b/lib/lzo/lzo1x_decompress_safe.c
index 569985d..8563081 100644
--- a/lib/lzo/lzo1x_decompress_safe.c
+++ b/lib/lzo/lzo1x_decompress_safe.c
@@ -19,11 +19,31 @@
#include <linux/lzo.h>
#include "lzodefs.h"
-#define HAVE_IP(x) ((size_t)(ip_end - ip) >= (size_t)(x))
-#define HAVE_OP(x) ((size_t)(op_end - op) >= (size_t)(x))
-#define NEED_IP(x) if (!HAVE_IP(x)) goto input_overrun
-#define NEED_OP(x) if (!HAVE_OP(x)) goto output_overrun
-#define TEST_LB(m_pos) if ((m_pos) < out) goto lookbehind_overrun
+#define HAVE_IP(t, x) \
+ (((size_t)(ip_end - ip) >= (size_t)(t + x)) && \
+ (((t + x) >= t) && ((t + x) >= x)))
+
+#define HAVE_OP(t, x) \
+ (((size_t)(op_end - op) >= (size_t)(t + x)) && \
+ (((t + x) >= t) && ((t + x) >= x)))
+
+#define NEED_IP(t, x) \
+ do { \
+ if (!HAVE_IP(t, x)) \
+ goto input_overrun; \
+ } while (0)
+
+#define NEED_OP(t, x) \
+ do { \
+ if (!HAVE_OP(t, x)) \
+ goto output_overrun; \
+ } while (0)
+
+#define TEST_LB(m_pos) \
+ do { \
+ if ((m_pos) < out) \
+ goto lookbehind_overrun; \
+ } while (0)
int lzo1x_decompress_safe(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len)
@@ -58,14 +78,14 @@ int lzo1x_decompress_safe(const unsigned char *in, size_t in_len,
while (unlikely(*ip == 0)) {
t += 255;
ip++;
- NEED_IP(1);
+ NEED_IP(1, 0);
}
t += 15 + *ip++;
}
t += 3;
copy_literal_run:
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
- if (likely(HAVE_IP(t + 15) && HAVE_OP(t + 15))) {
+ if (likely(HAVE_IP(t, 15) && HAVE_OP(t, 15))) {
const unsigned char *ie = ip + t;
unsigned char *oe = op + t;
do {
@@ -81,8 +101,8 @@ copy_literal_run:
} else
#endif
{
- NEED_OP(t);
- NEED_IP(t + 3);
+ NEED_OP(t, 0);
+ NEED_IP(t, 3);
do {
*op++ = *ip++;
} while (--t > 0);
@@ -95,7 +115,7 @@ copy_literal_run:
m_pos -= t >> 2;
m_pos -= *ip++ << 2;
TEST_LB(m_pos);
- NEED_OP(2);
+ NEED_OP(2, 0);
op[0] = m_pos[0];
op[1] = m_pos[1];
op += 2;
@@ -119,10 +139,10 @@ copy_literal_run:
while (unlikely(*ip == 0)) {
t += 255;
ip++;
- NEED_IP(1);
+ NEED_IP(1, 0);
}
t += 31 + *ip++;
- NEED_IP(2);
+ NEED_IP(2, 0);
}
m_pos = op - 1;
next = get_unaligned_le16(ip);
@@ -137,10 +157,10 @@ copy_literal_run:
while (unlikely(*ip == 0)) {
t += 255;
ip++;
- NEED_IP(1);
+ NEED_IP(1, 0);
}
t += 7 + *ip++;
- NEED_IP(2);
+ NEED_IP(2, 0);
}
next = get_unaligned_le16(ip);
ip += 2;
@@ -154,7 +174,7 @@ copy_literal_run:
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
if (op - m_pos >= 8) {
unsigned char *oe = op + t;
- if (likely(HAVE_OP(t + 15))) {
+ if (likely(HAVE_OP(t, 15))) {
do {
COPY8(op, m_pos);
op += 8;
@@ -164,7 +184,7 @@ copy_literal_run:
m_pos += 8;
} while (op < oe);
op = oe;
- if (HAVE_IP(6)) {
+ if (HAVE_IP(6, 0)) {
state = next;
COPY4(op, ip);
op += next;
@@ -172,7 +192,7 @@ copy_literal_run:
continue;
}
} else {
- NEED_OP(t);
+ NEED_OP(t, 0);
do {
*op++ = *m_pos++;
} while (op < oe);
@@ -181,7 +201,7 @@ copy_literal_run:
#endif
{
unsigned char *oe = op + t;
- NEED_OP(t);
+ NEED_OP(t, 0);
op[0] = m_pos[0];
op[1] = m_pos[1];
op += 2;
@@ -194,15 +214,15 @@ match_next:
state = next;
t = next;
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
- if (likely(HAVE_IP(6) && HAVE_OP(4))) {
+ if (likely(HAVE_IP(6, 0) && HAVE_OP(4, 0))) {
COPY4(op, ip);
op += t;
ip += t;
} else
#endif
{
- NEED_IP(t + 3);
- NEED_OP(t);
+ NEED_IP(t, 3);
+ NEED_OP(t, 0);
while (t > 0) {
*op++ = *ip++;
t--;
--
1.9.1
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