1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
From 6df0d3e2916c223dbe4262bf1b876dff1cb3f980 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Wed, 12 Dec 2012 12:28:45 +0100
Subject: [PATCH] alsdec: check block length
Upstream-Status: Backport
Commit 6df0d3e2916c223dbe4262bf1b876dff1cb3f980 release/1.0
Fix writing over the end
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 0ceca269b66ec12a23bf0907bd2c220513cdbf16)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
---
libavcodec/alsdec.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index 46dd0b4..1095b01 100644
--- a/gst-libs/ext/libav/libavcodec/alsdec.c
+++ b/gst-libs/ext/libav/libavcodec/alsdec.c
@@ -552,12 +552,15 @@ static void get_block_sizes(ALSDecContext *ctx, unsigned int *div_blocks,
/** Read the block data for a constant block
*/
-static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
+static int read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
{
ALSSpecificConfig *sconf = &ctx->sconf;
AVCodecContext *avctx = ctx->avctx;
GetBitContext *gb = &ctx->gb;
+ if (bd->block_length <= 0)
+ return -1;
+
*bd->raw_samples = 0;
*bd->const_block = get_bits1(gb); // 1 = constant value, 0 = zero block (silence)
bd->js_blocks = get_bits1(gb);
@@ -572,6 +575,8 @@ static void read_const_block_data(ALSDecContext *ctx, ALSBlockData *bd)
// ensure constant block decoding by reusing this field
*bd->const_block = 1;
+
+ return 0;
}
@@ -971,7 +976,8 @@ static int read_block(ALSDecContext *ctx, ALSBlockData *bd)
if (read_var_block_data(ctx, bd))
return -1;
} else {
- read_const_block_data(ctx, bd);
+ if (read_const_block_data(ctx, bd) < 0)
+ return -1;
}
return 0;
--
|
