From b18a571e2355a6fb0dcb7ff7de18d36694eb65bd Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Fri, 18 Nov 2016 17:00:30 +0100 Subject: [PATCH] avformat: Add max_streams option This allows user apps to stop OOM due to excessive number of streams Signed-off-by: Michael Niedermayer (cherry picked from commit 1296f844955e513d19051c962656f829479d4fb9) Signed-off-by: Michael Niedermayer --- doc/formats.texi | 4 ++++ libavformat/avformat.h | 7 +++++++ libavformat/options_table.h | 1 + libavformat/utils.c | 2 +- 4 files changed, 13 insertions(+), 1 deletion(-) diff --git a/doc/formats.texi b/doc/formats.texi index 2c068c1046..a2d72e6572 100644 --- a/doc/formats.texi +++ b/doc/formats.texi @@ -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 diff --git a/libavformat/avformat.h b/libavformat/avformat.h index 818184e5a8..4e7c615d33 100644 --- a/libavformat/avformat.h +++ b/libavformat/avformat.h @@ -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); diff --git a/libavformat/options_table.h b/libavformat/options_table.h index 3b74d1b2fd..930813a9d1 100644 --- a/libavformat/options_table.h +++ b/libavformat/options_table.h @@ -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}, }; diff --git a/libavformat/utils.c b/libavformat/utils.c index 7c53050f03..f1198c0079 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -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)