|
 |
6ed69d |
From 4b4cac39ba7988df9d8def32360dd842b707ba74 Mon Sep 17 00:00:00 2001
|
|
|
6ed69d |
From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
|
|
|
6ed69d |
Date: Sat, 8 Jun 2019 17:57:43 -0700
|
|
|
6ed69d |
Subject: [PATCH 01/11] CVE-2019-7572: Fix a buffer overread in
|
|
|
6ed69d |
IMA_ADPCM_nibble If an IMA ADPCM block contained an initial index out of step
|
|
|
6ed69d |
table range (loaded in IMA_ADPCM_decode()), IMA_ADPCM_nibble() blindly used
|
|
|
6ed69d |
this bogus value and that lead to a buffer overread.
|
|
|
6ed69d |
MIME-Version: 1.0
|
|
|
6ed69d |
Content-Type: text/plain; charset=UTF-8
|
|
|
6ed69d |
Content-Transfer-Encoding: 8bit
|
|
|
6ed69d |
|
|
|
6ed69d |
This patch fixes it by moving clamping the index value at the
|
|
|
6ed69d |
beginning of IMA_ADPCM_nibble() function instead of the end after
|
|
|
6ed69d |
an update.
|
|
|
6ed69d |
|
|
|
6ed69d |
CVE-2019-7572
|
|
|
6ed69d |
https://bugzilla.libsdl.org/show_bug.cgi?id=4495
|
|
|
6ed69d |
|
|
|
6ed69d |
Signed-off-by: Petr Písař <ppisar@redhat.com>
|
|
|
6ed69d |
|
|
|
6ed69d |
--HG--
|
|
|
6ed69d |
branch : SDL-1.2
|
|
|
6ed69d |
---
|
|
|
6ed69d |
src/audio/SDL_wave.c | 14 ++++++++------
|
|
|
6ed69d |
1 file changed, 8 insertions(+), 6 deletions(-)
|
|
|
6ed69d |
|
|
|
6ed69d |
diff --git a/src/audio/SDL_wave.c b/src/audio/SDL_wave.c
|
|
|
6ed69d |
index b4ad6c787..ba1fb5252 100644
|
|
|
6ed69d |
--- a/src/audio/SDL_wave.c
|
|
|
6ed69d |
+++ b/src/audio/SDL_wave.c
|
|
|
6ed69d |
@@ -264,6 +264,14 @@ static Sint32 IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state,Uint8 nybble)
|
|
|
6ed69d |
};
|
|
|
6ed69d |
Sint32 delta, step;
|
|
|
6ed69d |
|
|
|
6ed69d |
+ /* Clamp index value. The inital value can be invalid. */
|
|
|
6ed69d |
+ if ( state->index > 88 ) {
|
|
|
6ed69d |
+ state->index = 88;
|
|
|
6ed69d |
+ } else
|
|
|
6ed69d |
+ if ( state->index < 0 ) {
|
|
|
6ed69d |
+ state->index = 0;
|
|
|
6ed69d |
+ }
|
|
|
6ed69d |
+
|
|
|
6ed69d |
/* Compute difference and new sample value */
|
|
|
6ed69d |
step = step_table[state->index];
|
|
|
6ed69d |
delta = step >> 3;
|
|
|
6ed69d |
@@ -275,12 +283,6 @@ static Sint32 IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state,Uint8 nybble)
|
|
|
6ed69d |
|
|
|
6ed69d |
/* Update index value */
|
|
|
6ed69d |
state->index += index_table[nybble];
|
|
|
6ed69d |
- if ( state->index > 88 ) {
|
|
|
6ed69d |
- state->index = 88;
|
|
|
6ed69d |
- } else
|
|
|
6ed69d |
- if ( state->index < 0 ) {
|
|
|
6ed69d |
- state->index = 0;
|
|
|
6ed69d |
- }
|
|
|
6ed69d |
|
|
|
6ed69d |
/* Clamp output sample */
|
|
|
6ed69d |
if ( state->sample > max_audioval ) {
|
|
|
6ed69d |
--
|
|
|
6ed69d |
2.21.0
|
|
|
6ed69d |
|