avcodec/mjpegdec: Fix context fields becoming inconsistent

Fixes out of array access
Fixes: asan_heap-oob_1ca4f85_2760_cov_144449187_miss_congeniality_pegasus_ljpg.avi
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 0eecf40935)

Conflicts:

	libavcodec/mjpegdec.c
(cherry picked from commit 32d3acac727f3f4a6489ca129a5ea4ccdfcb34a5)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-11-25 13:53:06 +01:00
parent ec640e10b2
commit aebfcf7d62

View File

@ -1376,6 +1376,8 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
}
if (id == AV_RL32("LJIF")) {
int rgb = s->rgb;
int pegasus_rct = s->pegasus_rct;
if (s->avctx->debug & FF_DEBUG_PICT_INFO)
av_log(s->avctx, AV_LOG_INFO,
"Pegasus lossless jpeg header found\n");
@ -1385,17 +1387,27 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
skip_bits(&s->gb, 16); /* unknwon always 0? */
switch (get_bits(&s->gb, 8)) {
case 1:
s->rgb = 1;
s->pegasus_rct = 0;
rgb = 1;
pegasus_rct = 0;
break;
case 2:
s->rgb = 1;
s->pegasus_rct = 1;
rgb = 1;
pegasus_rct = 1;
break;
default:
av_log(s->avctx, AV_LOG_ERROR, "unknown colorspace\n");
}
len -= 9;
if (s->got_picture)
if (rgb != s->rgb || pegasus_rct != s->pegasus_rct) {
av_log(s->avctx, AV_LOG_WARNING, "Mismatching LJIF tag\n");
goto out;
}
s->rgb = rgb;
s->pegasus_rct = pegasus_rct;
goto out;
}