[FFmpeg-cvslog] avcodec/pixlet: Fixes: undefined shift in av_mod_uintp2()

Michael Niedermayer git at videolan.org
Sun Aug 20 22:15:33 EEST 2017


ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Fri Aug 18 16:42:59 2017 +0200| [8754ccd3b319fdf4e2beed5657a3e327999c64ce] | committer: Michael Niedermayer

avcodec/pixlet: Fixes: undefined shift in av_mod_uintp2()

Fixes: runtime error: shift exponent 4294967289 is too large for 32-bit type 'int'
Fixes: 3030/clusterfuzz-testcase-minimized-4649809254285312

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=8754ccd3b319fdf4e2beed5657a3e327999c64ce
---

 libavcodec/pixlet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/pixlet.c b/libavcodec/pixlet.c
index 088226bdda..a9cfe085c9 100644
--- a/libavcodec/pixlet.c
+++ b/libavcodec/pixlet.c
@@ -262,7 +262,7 @@ static int read_high_coeffs(AVCodecContext *avctx, uint8_t *src, int16_t *dst, i
 
         flag = 0;
 
-        if (state * 4ULL > 0xFF || i >= size)
+        if ((uint64_t)state > 0xFF / 4 || i >= size)
             continue;
 
         pfx = ((state + 8) >> 5) + (state ? ff_clz(state): 32) - 24;



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