Remove libavutils from the asan suppression list (#5783)

* Remove libavutils from the asan suppression list
- keeps suppression for FFmpegDemuxer from the PyNvVideoCodec
  DALI doesn't have control on
- fixes leaks from libavutils

Signed-off-by: Janusz Lisiecki <[email protected]>

Author: JanuszL

Diff for: dali/operators/reader/loader/video/frames_decoder.cc

@@ -236,6 +236,10 @@ FramesDecoder::FramesDecoder(const char *memory_file, int memory_file_size, bool
 
   int ret = avformat_open_input(&av_state_->ctx_, "", nullptr, nullptr);
   if (ret != 0) {
+    // av_state_->ctx_ is nullified so we need to free the memory here instead of the
+    // AvState destructor which cannot access it through av_state_->ctx_ anymore
+    av_freep(&av_io_context->buffer);
+    avio_context_free(&av_io_context);
     DALI_WARN(make_string("Failed to open video file \"", Filename(), "\", due to ",
                           detail::av_error_string(ret)));
     return;
@@ -284,13 +288,14 @@ void FramesDecoder::CreateAvState(std::unique_ptr<AvState> &av_state, bool init_
     av_state->ctx_->pb = av_io_context;
 
     int ret = avformat_open_input(&av_state->ctx_, "", nullptr, nullptr);
-    DALI_ENFORCE(
-      ret == 0,
-      make_string(
-        "Failed to open video file \"",
-        Filename(),
-        "\", due to ",
-        detail::av_error_string(ret)));
+    if (ret != 0) {
+      // av_state_->ctx_ is nullified so we need to free the memory here instead of the
+      // AvState destructor which cannot access it through av_state_->ctx_ anymore
+      av_freep(&av_io_context->buffer);
+      avio_context_free(&av_io_context);
+      DALI_FAIL(make_string("Failed to open video file \"", Filename(), "\", due to ",
+                            detail::av_error_string(ret)));
+    }
     av_state->stream_id_ = av_find_best_stream(
       av_state->ctx_, AVMEDIA_TYPE_VIDEO, -1, -1, nullptr, 0);
     av_state->codec_params_ = av_state->ctx_->streams[av_state->stream_id_]->codecpar;

Diff for: dali/operators/reader/loader/video/frames_decoder.h

@@ -60,12 +60,15 @@ struct AvState {
     avcodec_free_context(&codec_ctx_);
     if (ctx_ != nullptr) {
       // if we use avio_alloc_context we need a custom deallocator for ctx_->pb
-      if (ctx_->flags & AVFMT_FLAG_CUSTOM_IO) {
-        av_freep(&ctx_->pb->buffer);
-        av_freep(&ctx_->pb);
-      }
+      auto custom_dealloc = ctx_->flags & AVFMT_FLAG_CUSTOM_IO;
+      auto custom_ctx = ctx_->pb;
+      auto custom_buffer = ctx_->pb ? ctx_->pb->buffer : nullptr;
       avformat_close_input(&ctx_);
       avformat_free_context(ctx_);
+      if (custom_dealloc) {
+        av_freep(&custom_buffer);
+        avio_context_free(&custom_ctx);
+      }
     }
 
     ctx_ = nullptr;

Diff for: dali/operators/reader/loader/video_loader.cc

@@ -266,6 +266,14 @@ static int64_t seek_file(void *opaque, int64_t offset, int whence) {
   }
 }
 
+void clean_avformat_context(AVFormatContext **p) {
+  if (*p && (*p)->flags & AVFMT_FLAG_CUSTOM_IO) {
+    if (*p && (*p)->pb) av_freep(&(*p)->pb->buffer);
+    avio_context_free(&(*p)->pb);
+  }
+  avformat_close_input(p);
+}
+
 VideoFile& VideoLoader::get_or_open_file(const std::string &filename) {
   static VideoFile empty_file = {};
   auto& file = open_files_[filename];
@@ -299,12 +307,16 @@ VideoFile& VideoLoader::get_or_open_file(const std::string &filename) {
     // if avformat_open_input fails it frees raw_fmt_ctx so we can release it from unique_ptr
     int ret = avformat_open_input(&tmp_raw_fmt_ctx, NULL, NULL, NULL);
     if (ret < 0) {
+      // avio_ctx->ctx_ is nullified so we need to free the memory here instead of the
+      // AVFormatContext destructor which cannot access it through avio_ctx->ctx_ anymore
+      av_freep(&avio_ctx->buffer);
+      avio_context_free(&avio_ctx);
       DALI_WARN(make_string("Failed to open video file ", filename, " because of ",
                             av_err2str(ret)));
       open_files_.erase(filename);
       return empty_file;
     }
-    file.fmt_ctx_ = make_unique_av<AVFormatContext>(tmp_raw_fmt_ctx, avformat_close_input);
+    file.fmt_ctx_ = make_unique_av<AVFormatContext>(tmp_raw_fmt_ctx, clean_avformat_context);
     LOG_LINE << "File open " << filename << std::endl;
 
     LOG_LINE << "File info fetched for " << filename << std::endl;
@@ -398,6 +410,8 @@ VideoFile& VideoLoader::get_or_open_file(const std::string &filename) {
       if (pkt.stream_index == file.vid_stream_idx_) break;
       av_packet_unref(&pkt);
     }
+    auto pkt_duration = pkt.duration;
+    av_packet_unref(&pkt);
 
     if (ret < 0) {
       DALI_WARN(make_string("Unable to read frame from file :", filename));
@@ -406,10 +420,9 @@ VideoFile& VideoLoader::get_or_open_file(const std::string &filename) {
     }
 
     DALI_ENFORCE(skip_vfr_check_ ||
-      almost_equal(av_q2d(file.frame_base_), pkt.duration * av_q2d(file.stream_base_), 2),
+      almost_equal(av_q2d(file.frame_base_), pkt_duration * av_q2d(file.stream_base_), 2),
       "Variable frame rate videos are unsupported. This heuristic can yield false positives. "
       "The check can be disabled via the skip_vfr_check flag. Check failed for file: " + filename);
-    av_packet_unref(&pkt);
     // empty the read buffer from av_read_frame to save the memory usage
     avformat_flush(file.fmt_ctx_.get());
 

Diff for: qa/leak.sup

@@ -11,8 +11,8 @@ leak:numba
 leak:libmxnet
 leak:libtorch
 leak:libc10
-leak:av_realloc_f
-leak:av_malloc
+# we don't control FFmpegDemuxer destructor so we cannot fix that in DALI
+leak:FFmpegDemuxer
 # tensorflow
 leak:PyInit__pywrap_debug_events_writer
 leak:_pywrap