The value_len is an uint32 not an int32 per spec. That value must not be truncated, neither by casting to int, nor by any conditional checks, because at the end of get_tag, this value is needed to move forward in parsing. When the len value gets modified, the parsing may break.
Signed-off-by: softworkz <softwo...@hotmail.com> --- v5: Split into pieces as requested libavformat/asfdec_f.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/libavformat/asfdec_f.c b/libavformat/asfdec_f.c index 076b5ab147..d017fae019 100644 --- a/libavformat/asfdec_f.c +++ b/libavformat/asfdec_f.c @@ -218,7 +218,7 @@ static uint64_t get_value(AVIOContext *pb, int type, int type2_size) } } -static void get_tag(AVFormatContext *s, const char *key, int type, int len, int type2_size) +static void get_tag(AVFormatContext *s, const char *key, int type, uint32_t len, int type2_size) { ASFContext *asf = s->priv_data; char *value = NULL; @@ -528,7 +528,7 @@ static int asf_read_ext_stream_properties(AVFormatContext *s, int64_t size) static int asf_read_content_desc(AVFormatContext *s, int64_t size) { AVIOContext *pb = s->pb; - int len1, len2, len3, len4, len5; + uint32_t len1, len2, len3, len4, len5; len1 = avio_rl16(pb); len2 = avio_rl16(pb); @@ -602,25 +602,23 @@ static int asf_read_metadata(AVFormatContext *s, int64_t size) { AVIOContext *pb = s->pb; ASFContext *asf = s->priv_data; - int n, stream_num, name_len_utf16, name_len_utf8, value_len; + int n, name_len_utf8; + uint16_t stream_num, name_len_utf16, value_type; + uint32_t value_len; int ret, i; n = avio_rl16(pb); for (i = 0; i < n; i++) { uint8_t *name; - int value_type; avio_rl16(pb); // lang_list_index - stream_num = avio_rl16(pb); - name_len_utf16 = avio_rl16(pb); - value_type = avio_rl16(pb); /* value_type */ - value_len = avio_rl32(pb); + stream_num = (uint16_t)avio_rl16(pb); + name_len_utf16 = (uint16_t)avio_rl16(pb); + value_type = (uint16_t)avio_rl16(pb); /* value_type */ + value_len = avio_rl32(pb); - if (value_len < 0 || value_len > UINT16_MAX) - return AVERROR_INVALIDDATA; - - name_len_utf8 = 2*name_len_utf16 + 1; - name = av_malloc(name_len_utf8); + name_len_utf8 = 2 * name_len_utf16 + 1; + name = av_malloc(name_len_utf8); if (!name) return AVERROR(ENOMEM); -- 2.30.2.windows.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".