From 0d81c0a10ee822e6198ab0c0868ac7e22ca9ac4e Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Sat, 21 Mar 2020 17:23:52 +0100 Subject: avformat: Redo cleanup of demuxers upon read_header() failure If reading the header fails, the demuxer's read_close() function (if existing) is not called automatically; instead several demuxers call it via "goto fail" in read_header(). This commit intends to change this by adding an internal flag for demuxers that can be used to set on a per-AVInputFormat basis whether read_close() should be called generically after an error during read_header(). The flag controlling this behaviour needs to be added because it might be unsafe to call read_close() generally (e.g. this might lead to read_close() being called twice and this might e.g. lead to double-frees if av_free() is used instead of av_freep(); or a size field has not been reset after freeing the elements (see the mov demuxer for an example of this)). Signed-off-by: Andreas Rheinhardt --- libavformat/internal.h | 6 ++++++ libavformat/utils.c | 5 ++++- 2 files changed, 10 insertions(+), 1 deletion(-) (limited to 'libavformat') diff --git a/libavformat/internal.h b/libavformat/internal.h index c6adf7b872..240de9e289 100644 --- a/libavformat/internal.h +++ b/libavformat/internal.h @@ -42,6 +42,12 @@ # define hex_dump_debug(class, buf, size) do { if (0) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size); } while(0) #endif +/** + * For an AVInputFormat with this flag set read_close() needs to be called + * by the caller upon read_header() failure. + */ +#define FF_FMT_INIT_CLEANUP (1 << 0) + typedef struct AVCodecTag { enum AVCodecID id; unsigned int tag; diff --git a/libavformat/utils.c b/libavformat/utils.c index 0df14682a4..998fddf270 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -566,8 +566,11 @@ int avformat_open_input(AVFormatContext **ps, const char *filename, ff_id3v2_read_dict(s->pb, &s->internal->id3v2_meta, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta); if (s->iformat->read_header) - if ((ret = s->iformat->read_header(s)) < 0) + if ((ret = s->iformat->read_header(s)) < 0) { + if (s->iformat->flags_internal & FF_FMT_INIT_CLEANUP) + goto close; goto fail; + } if (!s->metadata) { s->metadata = s->internal->id3v2_meta; -- cgit v1.2.3