avcodec/decode: Fix leaks upon subtitle decoding errors

Up until now, various subtitle decoders have not cleaned up
the AVSubtitle on error; this task must not be left to the user
because the documentation explicitly states that the AVSubtitle
"must be freed with avsubtitle_free if *got_sub_ptr is set"
(which it isn't on error).
Leaks happen upon failure in ff_ass_add_rect() or in
ass_decode_frame(); freeing generically also allows to remove
now redundant freeing code in pgssubdec and dvbsubdec.
While just at it, also reset got_sub_ptr generically on error.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2021-12-10 22:05:20 +01:00
parent d59f454ed2
commit cee04cbfe1
3 changed files with 9 additions and 11 deletions

View File

@ -834,8 +834,14 @@ int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
sub->pts = av_rescale_q(avpkt->pts,
avctx->pkt_timebase, AV_TIME_BASE_Q);
ret = avctx->codec->decode(avctx, sub, got_sub_ptr, pkt);
av_assert1((ret >= 0) >= !!*got_sub_ptr &&
!!*got_sub_ptr >= !!sub->num_rects);
if (pkt == avci->buffer_pkt) // did we recode?
av_packet_unref(avci->buffer_pkt);
if (ret < 0) {
*got_sub_ptr = 0;
avsubtitle_free(sub);
return ret;
}
av_assert1(!sub->num_rects || *got_sub_ptr);
if (sub->num_rects && !sub->end_display_time && avpkt->duration &&
avctx->pkt_timebase.num) {
@ -863,9 +869,6 @@ int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
if (*got_sub_ptr)
avctx->frame_number++;
if (pkt == avci->buffer_pkt) // did we recode?
av_packet_unref(avci->buffer_pkt);
}
return ret;

View File

@ -1715,8 +1715,6 @@ static int dvbsub_decode(AVCodecContext *avctx,
end:
if (ret < 0) {
*got_sub_ptr = 0;
avsubtitle_free(sub);
return ret;
} else {
if (ctx->compute_edt == 1)

View File

@ -667,11 +667,8 @@ static int decode(AVCodecContext *avctx, void *data, int *got_sub_ptr,
break;
}
if (ret < 0 && (ret == AVERROR(ENOMEM) ||
avctx->err_recognition & AV_EF_EXPLODE)) {
avsubtitle_free(data);
*got_sub_ptr = 0;
avctx->err_recognition & AV_EF_EXPLODE))
return ret;
}
buf += segment_length;
}