avformat: Add max_streams option

This allows user apps to stop OOM due to excessive number of streams

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 1296f84495)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2016-11-18 17:00:30 +01:00
parent 0131f5c376
commit b18a571e23
4 changed files with 13 additions and 1 deletions

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@ -205,6 +205,10 @@ For example to separate the fields with newlines and indention:
ffprobe -dump_separator "
" -i ~/videos/matrixbench_mpeg2.mpg
@end example
@item max_streams @var{integer} (@emph{input})
Specifies the maximum number of streams. This can be used to reject files that
would require too many resources due to a large number of streams.
@end table
@c man end FORMAT OPTIONS

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@ -1884,6 +1884,13 @@ typedef struct AVFormatContext {
* - decoding: set by user through AVOptions (NO direct access)
*/
char *protocol_blacklist;
/**
* The maximum number of streams.
* - encoding: unused
* - decoding: set by user through AVOptions (NO direct access)
*/
int max_streams;
} AVFormatContext;
int av_format_get_probe_score(const AVFormatContext *s);

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@ -103,6 +103,7 @@ static const AVOption avformat_options[] = {
{"format_whitelist", "List of demuxers that are allowed to be used", OFFSET(format_whitelist), AV_OPT_TYPE_STRING, { .str = NULL }, CHAR_MIN, CHAR_MAX, D },
{"protocol_whitelist", "List of protocols that are allowed to be used", OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL }, CHAR_MIN, CHAR_MAX, D },
{"protocol_blacklist", "List of protocols that are not allowed to be used", OFFSET(protocol_blacklist), AV_OPT_TYPE_STRING, { .str = NULL }, CHAR_MIN, CHAR_MAX, D },
{"max_streams", "maximum number of streams", OFFSET(max_streams), AV_OPT_TYPE_INT, { .i64 = INT_MAX }, 0, INT_MAX, D },
{NULL},
};

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@ -4087,7 +4087,7 @@ AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c)
int i;
AVStream **streams;
if (s->nb_streams >= INT_MAX/sizeof(*streams))
if (s->nb_streams >= FFMIN(s->max_streams, INT_MAX/sizeof(*streams)))
return NULL;
streams = av_realloc_array(s->streams, s->nb_streams + 1, sizeof(*streams));
if (!streams)