[FFmpeg-devel] [PATCH 3/3] avcodec/bink: disallow odd positioned scaled blocks

[Michael Niedermayer]

Fixes: out of array access
Fixes: 47911/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_BINK_fuzzer-6194020855971840

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/bink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/bink.c b/libavcodec/bink.c
index ce740ad275..ed4406d97d 100644
--- a/libavcodec/bink.c
+++ b/libavcodec/bink.c
@@ -1088,7 +1088,7 @@ static int bink_decode_plane(BinkContext *c, AVFrame *frame, GetBitContext *gb,
         for (bx = 0; bx < bw; bx++, dst += 8, prev += 8) {
             blk = get_value(c, BINK_SRC_BLOCK_TYPES);
             // 16x16 block type on odd line means part of the already decoded block, so skip it
-            if ((by & 1) && blk == SCALED_BLOCK) {
+            if (((by & 1) || (bx & 1)) && blk == SCALED_BLOCK) {
                 bx++;
                 dst  += 8;
                 prev += 8;
-- 
2.17.1