avcodec/h264_slice: Do not attempt to render into frames already output

Fixes: null pointer dereference
Fixes: 4698/clusterfuzz-testcase-minimized-5096956322906112

This testcase does not reproduce the issue before 03b82b3ab9

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2018-01-03 23:42:01 +01:00
parent 3c0a081a1e
commit 476665d4de

View File

@ -1571,6 +1571,12 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl,
* one except for reference purposes. */
h->first_field = 1;
h->cur_pic_ptr = NULL;
} else if (h->cur_pic_ptr->reference & DELAYED_PIC_REF) {
/* This frame was already output, we cannot draw into it
* anymore.
*/
h->first_field = 1;
h->cur_pic_ptr = NULL;
} else {
/* Second field in complementary pair */
h->first_field = 0;