diff mbox series

[FFmpeg-devel,1/3] avcodec/jpeglsdec: fix end check for xfrm

Message ID 20220609213741.18029-1-michael@niedermayer.cc
State Accepted
Commit 6a82412bf33108111eb3f63076fd5a51349ae114
Headers show
Series [FFmpeg-devel,1/3] avcodec/jpeglsdec: fix end check for xfrm | expand

Checks

Context Check Description
andriy/make_x86 success Make finished
andriy/make_fate_x86 success Make fate finished

Commit Message

Michael Niedermayer June 9, 2022, 9:37 p.m. UTC 
Fixes: out of array access
Fixes: 47871/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AMV_fuzzer-5646305956855808

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/jpeglsdec.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Comments

Michael Niedermayer June 22, 2022, 12:03 a.m. UTC | #1 
On Thu, Jun 09, 2022 at 11:37:39PM +0200, Michael Niedermayer wrote:
> Fixes: out of array access
> Fixes: 47871/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AMV_fuzzer-5646305956855808
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/jpeglsdec.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

will apply

[...]
diff mbox series

Patch

diff --git a/libavcodec/jpeglsdec.c b/libavcodec/jpeglsdec.c
index 399837cf2f..ab663dc1fc 100644
--- a/libavcodec/jpeglsdec.c
+++ b/libavcodec/jpeglsdec.c
@@ -484,19 +484,19 @@  int ff_jpegls_decode_picture(MJpegDecodeContext *s, int near,
             for (i = 0; i < s->height; i++) {
                 switch(s->xfrm) {
                 case 1:
-                    for (x = off; x < w; x += 3) {
+                    for (x = off; x + 2 < w; x += 3) {
                         src[x  ] += src[x+1] + 128;
                         src[x+2] += src[x+1] + 128;
                     }
                     break;
                 case 2:
-                    for (x = off; x < w; x += 3) {
+                    for (x = off; x + 2 < w; x += 3) {
                         src[x  ] += src[x+1] + 128;
                         src[x+2] += ((src[x  ] + src[x+1])>>1) + 128;
                     }
                     break;
                 case 3:
-                    for (x = off; x < w; x += 3) {
+                    for (x = off; x + 2 < w; x += 3) {
                         int g = src[x+0] - ((src[x+2]+src[x+1])>>2) + 64;
                         src[x+0] = src[x+2] + g + 128;
                         src[x+2] = src[x+1] + g + 128;
@@ -504,7 +504,7 @@  int ff_jpegls_decode_picture(MJpegDecodeContext *s, int near,
                     }
                     break;
                 case 4:
-                    for (x = off; x < w; x += 3) {
+                    for (x = off; x + 2 < w; x += 3) {
                         int r    = src[x+0] - ((                       359 * (src[x+2]-128) + 490) >> 8);
                         int g    = src[x+0] - (( 88 * (src[x+1]-128) - 183 * (src[x+2]-128) +  30) >> 8);
                         int b    = src[x+0] + ((454 * (src[x+1]-128)                        + 574) >> 8);