| Message ID | 20190806213006.25210-5-michael@niedermayer.cc |
|---|---|
| State | Accepted |
| Commit | 859362a6f01dabaf28f189e395724c89b1e89ffd |
| Headers | show |
Aug 6, 2019, 10:30 PM by michael@niedermayer.cc: > This avoids unneeded operations and makes the code faster. > > Fixes: Timeout (12sec -> 9sec) > Fixes: 15724/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PAF_VIDEO_fuzzer-5750842205929472 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/pafvideo.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/pafvideo.c b/libavcodec/pafvideo.c > index 323c662c59..72d5d4b523 100644 > --- a/libavcodec/pafvideo.c > +++ b/libavcodec/pafvideo.c > @@ -55,6 +55,7 @@ typedef struct PAFVideoDecContext { > > int current_frame; > uint8_t *frame[4]; > + int dirty[4]; > int frame_size; > int video_size; > > @@ -187,6 +188,7 @@ static int decode_0(PAFVideoDecContext *c, uint8_t *pkt, uint8_t code) > j = bytestream2_get_le16(&c->gb) + offset; > if (bytestream2_get_bytes_left(&c->gb) < (j - offset) * 16) > return AVERROR_INVALIDDATA; > + c->dirty[page] = 1; > do { > offset++; > if (dst + 3 * c->width + 4 > dend) > @@ -329,9 +331,13 @@ static int paf_video_decode(AVCodecContext *avctx, void *data, > c->pic->palette_has_changed = 1; > } > > + c->dirty[c->current_frame] = 1; > if (code & 0x20) > - for (i = 0; i < 4; i++) > - memset(c->frame[i], 0, c->frame_size); > + for (i = 0; i < 4; i++) { > + if (c->dirty[i]) > + memset(c->frame[i], 0, c->frame_size); > + c->dirty[i] = 0; > + } > The extra code doesn't justify that speedup.
diff --git a/libavcodec/pafvideo.c b/libavcodec/pafvideo.c index 323c662c59..72d5d4b523 100644 --- a/libavcodec/pafvideo.c +++ b/libavcodec/pafvideo.c @@ -55,6 +55,7 @@ typedef struct PAFVideoDecContext { int current_frame; uint8_t *frame[4]; + int dirty[4]; int frame_size; int video_size; @@ -187,6 +188,7 @@ static int decode_0(PAFVideoDecContext *c, uint8_t *pkt, uint8_t code) j = bytestream2_get_le16(&c->gb) + offset; if (bytestream2_get_bytes_left(&c->gb) < (j - offset) * 16) return AVERROR_INVALIDDATA; + c->dirty[page] = 1; do { offset++; if (dst + 3 * c->width + 4 > dend) @@ -329,9 +331,13 @@ static int paf_video_decode(AVCodecContext *avctx, void *data, c->pic->palette_has_changed = 1; } + c->dirty[c->current_frame] = 1; if (code & 0x20) - for (i = 0; i < 4; i++) - memset(c->frame[i], 0, c->frame_size); + for (i = 0; i < 4; i++) { + if (c->dirty[i]) + memset(c->frame[i], 0, c->frame_size); + c->dirty[i] = 0; + } switch (code & 0x0F) { case 0:
This avoids unneeded operations and makes the code faster. Fixes: Timeout (12sec -> 9sec) Fixes: 15724/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PAF_VIDEO_fuzzer-5750842205929472 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/pafvideo.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)