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| author | Kostya Shishkov <kostya.shishkov@gmail.com> | 2012-05-03 20:10:36 +0200 |
|---|---|---|
| committer | Kostya Shishkov <kostya.shishkov@gmail.com> | 2012-05-06 09:31:52 +0200 |
| commit | 8099187e897ddc90cb3902332c76fb2542dac308 (patch) | |
| tree | 6aa4b182b799c08cdf92fd4838f4d727d2592217 | |
| parent | 96f7590efd470f5e82084309a8d312d28becdaa8 (diff) | |
| download | ffmpeg-8099187e897ddc90cb3902332c76fb2542dac308.tar.gz | |
dfa: add some checks to ensure that decoder won't write past frame end
| -rw-r--r-- | libavcodec/dfa.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/libavcodec/dfa.c b/libavcodec/dfa.c index 788e9ca90a..4fe6519a93 100644 --- a/libavcodec/dfa.c +++ b/libavcodec/dfa.c @@ -164,6 +164,8 @@ static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height } else if (bitbuf & (mask << 1)) { frame += bytestream2_get_le16(gb) * 2; } else { + if (frame_end - frame < width + 2) + return AVERROR_INVALIDDATA; frame[0] = frame[1] = frame[width] = frame[width + 1] = bytestream2_get_byte(gb); frame += 2; @@ -224,6 +226,7 @@ static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height const uint8_t *frame_end = frame + width * height; uint8_t *line_ptr; int count, i, v, lines, segments; + int y = 0; lines = bytestream2_get_le16(gb); if (lines > height) @@ -234,10 +237,12 @@ static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height return -1; segments = bytestream2_get_le16u(gb); while ((segments & 0xC000) == 0xC000) { + unsigned skip_lines = -(int16_t)segments; unsigned delta = -((int16_t)segments * width); - if (frame_end - frame <= delta) + if (frame_end - frame <= delta || y + lines + skip_lines > height) return -1; frame += delta; + y += skip_lines; segments = bytestream2_get_le16(gb); } if (segments & 0x8000) { @@ -246,6 +251,7 @@ static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height } line_ptr = frame; frame += width; + y++; while (segments--) { if (frame - line_ptr <= bytestream2_peek_byte(gb)) return -1; |