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| author | Michael Niedermayer <michaelni@gmx.at> | 2012-03-03 03:50:05 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2012-03-03 03:50:05 +0100 |
| commit | 81d4b3af81b52a79f11705ef02d3f48747047404 (patch) | |
| tree | ae219ecaf8a299eb22a45c828072778a0f6795a9 /libavcodec/qpeg.c | |
| parent | 4299dfa5ded84111231a456ad102f65f6f62649e (diff) | |
| download | ffmpeg-81d4b3af81b52a79f11705ef02d3f48747047404.tar.gz | |
qpeg: fix overreads.
qpeg should probably be changed to use the checked bytestream reader.
But for now this fixes it and is significantly less work.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/qpeg.c')
| -rw-r--r-- | libavcodec/qpeg.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/libavcodec/qpeg.c b/libavcodec/qpeg.c index f2dba732bc..2d5ae690ca 100644 --- a/libavcodec/qpeg.c +++ b/libavcodec/qpeg.c @@ -143,7 +143,7 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, if(delta) { /* motion compensation */ - while((code & 0xF0) == 0xF0) { + while(size > 0 && (code & 0xF0) == 0xF0) { if(delta == 1) { int me_idx; int me_w, me_h, me_x, me_y; @@ -210,6 +210,9 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, } else if(code >= 0xC0) { /* copy code: 0xC0..0xDF */ code &= 0x1F; + if(code + 1 > size) + break; + for(i = 0; i <= code; i++) { dst[filled++] = *src++; if(filled >= width) { @@ -227,11 +230,11 @@ static void qpeg_decode_inter(const uint8_t *src, uint8_t *dst, int size, code &= 0x3F; /* codes 0x80 and 0x81 are actually escape codes, skip value minus constant is in the next byte */ - if(!code) - skip = (*src++) + 64; - else if(code == 1) - skip = (*src++) + 320; - else + if(!code) { + skip = (*src++) + 64; size--; + } else if(code == 1) { + skip = (*src++) + 320; size--; + } else skip = code; filled += skip; while( filled >= width) { |