avcodec/pthread_frame: Fix cleanup during init

In case an error happened when setting up the child threads,
ff_frame_thread_init() would up until now call ff_frame_thread_free()
to clean up all threads set up so far, including the current, not
properly initialized one.
But a half-allocated context needs special handling which
ff_frame_thread_frame_free() doesn't provide.
Notably, if allocating the AVCodecInternal, the codec's private data
or setting the options fails, the codec's close function will be
called (if there is one); it will also be called if the codec's init
function fails, regardless of whether the FF_CODEC_CAP_INIT_CLEANUP
is set. This is not supported by all codecs; in ticket #9099 it led
to a crash.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2021-02-11 13:45:31 +01:00
parent 24ee151402
commit e9b6617579
1 changed files with 67 additions and 70 deletions

View File

@ -64,6 +64,12 @@ enum {
STATE_SETUP_FINISHED,
};
enum {
UNINITIALIZED, ///< Thread has not been created, AVCodec->close mustn't be called
NEEDS_CLOSE, ///< AVCodec->close needs to be called
INITIALIZED, ///< Thread has been properly set up
};
/**
* Context used by codec threads and stored in their AVCodecInternal thread_ctx.
*/
@ -698,27 +704,40 @@ void ff_frame_thread_free(AVCodecContext *avctx, int thread_count)
for (i = 0; i < thread_count; i++) {
PerThreadContext *p = &fctx->threads[i];
AVCodecContext *ctx = p->avctx;
pthread_mutex_lock(&p->mutex);
p->die = 1;
pthread_cond_signal(&p->input_cond);
pthread_mutex_unlock(&p->mutex);
if (ctx->internal) {
if (p->thread_init == INITIALIZED) {
pthread_mutex_lock(&p->mutex);
p->die = 1;
pthread_cond_signal(&p->input_cond);
pthread_mutex_unlock(&p->mutex);
if (p->thread_init)
pthread_join(p->thread, NULL);
p->thread_init=0;
if (codec->close && p->avctx)
codec->close(p->avctx);
pthread_join(p->thread, NULL);
}
if (codec->close && p->thread_init != UNINITIALIZED)
codec->close(ctx);
#if FF_API_THREAD_SAFE_CALLBACKS
release_delayed_buffers(p);
release_delayed_buffers(p);
for (int j = 0; j < p->released_buffers_allocated; j++)
av_frame_free(&p->released_buffers[j]);
av_freep(&p->released_buffers);
#endif
av_frame_free(&p->frame);
}
if (ctx->priv_data) {
if (codec->priv_class)
av_opt_free(ctx->priv_data);
av_freep(&ctx->priv_data);
}
for (i = 0; i < thread_count; i++) {
PerThreadContext *p = &fctx->threads[i];
av_freep(&ctx->slice_offset);
av_buffer_unref(&ctx->internal->pool);
av_freep(&ctx->internal);
av_buffer_unref(&ctx->hw_frames_ctx);
}
av_frame_free(&p->frame);
pthread_mutex_destroy(&p->mutex);
pthread_mutex_destroy(&p->progress_mutex);
@ -727,26 +746,6 @@ void ff_frame_thread_free(AVCodecContext *avctx, int thread_count)
pthread_cond_destroy(&p->output_cond);
av_packet_free(&p->avpkt);
#if FF_API_THREAD_SAFE_CALLBACKS
for (int j = 0; j < p->released_buffers_allocated; j++)
av_frame_free(&p->released_buffers[j]);
av_freep(&p->released_buffers);
#endif
if (p->avctx) {
if (codec->priv_class)
av_opt_free(p->avctx->priv_data);
av_freep(&p->avctx->priv_data);
av_freep(&p->avctx->slice_offset);
}
if (p->avctx) {
av_buffer_unref(&p->avctx->internal->pool);
av_freep(&p->avctx->internal);
av_buffer_unref(&p->avctx->hw_frames_ctx);
}
av_freep(&p->avctx);
}
@ -763,47 +762,37 @@ void ff_frame_thread_free(AVCodecContext *avctx, int thread_count)
avctx->codec = NULL;
}
static av_cold int init_thread(PerThreadContext *p,
static av_cold int init_thread(PerThreadContext *p, int *threads_to_free,
FrameThreadContext *fctx, AVCodecContext *avctx,
AVCodecContext *src, const AVCodec *codec, int first)
{
AVCodecContext *copy = av_malloc(sizeof(AVCodecContext));
AVCodecContext *copy;
int err;
atomic_init(&p->state, STATE_INPUT_READY);
copy = av_memdup(src, sizeof(*src));
if (!copy)
return AVERROR(ENOMEM);
copy->priv_data = NULL;
/* From now on, this PerThreadContext will be cleaned up by
* ff_frame_thread_free in case of errors. */
(*threads_to_free)++;
pthread_mutex_init(&p->mutex, NULL);
pthread_mutex_init(&p->progress_mutex, NULL);
pthread_cond_init(&p->input_cond, NULL);
pthread_cond_init(&p->progress_cond, NULL);
pthread_cond_init(&p->output_cond, NULL);
p->frame = av_frame_alloc();
if (!p->frame) {
av_freep(&copy);
return AVERROR(ENOMEM);
}
p->avpkt = av_packet_alloc();
if (!p->avpkt) {
av_freep(&copy);
return AVERROR(ENOMEM);
}
p->parent = fctx;
p->avctx = copy;
p->parent = fctx;
p->avctx = copy;
if (!copy) {
return AVERROR(ENOMEM);
}
*copy = *src;
copy->internal = av_malloc(sizeof(AVCodecInternal));
if (!copy->internal) {
copy->priv_data = NULL;
return AVERROR(ENOMEM);
}
*copy->internal = *src->internal;
copy->internal = av_memdup(src->internal, sizeof(*src->internal));
if (!copy->internal)
return AVERROR(ENOMEM);
copy->internal->thread_ctx = p;
copy->internal->last_pkt_props = p->avpkt;
copy->delay = avctx->delay;
@ -821,14 +810,22 @@ static av_cold int init_thread(PerThreadContext *p,
}
}
if (!(p->frame = av_frame_alloc()) ||
!(p->avpkt = av_packet_alloc()))
return AVERROR(ENOMEM);
copy->internal->last_pkt_props = p->avpkt;
if (!first)
copy->internal->is_copy = 1;
if (codec->init)
err = codec->init(copy);
if (err < 0) {
if (codec->caps_internal & FF_CODEC_CAP_INIT_CLEANUP)
p->thread_init = NEEDS_CLOSE;
return err;
}
p->thread_init = NEEDS_CLOSE;
if (first)
update_context_from_thread(avctx, copy, 1);
@ -836,9 +833,10 @@ static av_cold int init_thread(PerThreadContext *p,
atomic_init(&p->debug_threads, (copy->debug & FF_DEBUG_THREADS) != 0);
err = AVERROR(pthread_create(&p->thread, NULL, frame_worker_thread, p));
p->thread_init= !err;
if(!p->thread_init)
return err;
if (err < 0)
return err;
p->thread_init = INITIALIZED;
return 0;
}
@ -885,11 +883,11 @@ int ff_frame_thread_init(AVCodecContext *avctx)
if (codec->type == AVMEDIA_TYPE_VIDEO)
avctx->delay = src->thread_count - 1;
for (i = 0; i < thread_count; i++) {
for (i = 0; i < thread_count; ) {
PerThreadContext *p = &fctx->threads[i];
int first = !i;
err = init_thread(p, fctx, avctx, src, codec, first);
err = init_thread(p, &i, fctx, avctx, src, codec, first);
if (err < 0)
goto error;
}
@ -897,8 +895,7 @@ int ff_frame_thread_init(AVCodecContext *avctx)
return 0;
error:
ff_frame_thread_free(avctx, i+1);
ff_frame_thread_free(avctx, i);
return err;
}