This fixes undefined behavior and other issues. No testcase, this was found by code review
Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> --- libavformat/mpeg.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/libavformat/mpeg.c b/libavformat/mpeg.c index 781c3162d6..fdc808dc50 100644 --- a/libavformat/mpeg.c +++ b/libavformat/mpeg.c @@ -756,12 +756,17 @@ static int vobsub_read_header(AVFormatContext *s) } fname_len = strlen(vobsub->sub_name); - ext = vobsub->sub_name - 3 + fname_len; - if (fname_len < 4 || *(ext - 1) != '.') { + if (fname_len < 4) { av_log(s, AV_LOG_ERROR, "The input index filename is too short " "to guess the associated .SUB file\n"); return AVERROR_INVALIDDATA; } + ext = vobsub->sub_name + fname_len - 3; + if (*(ext - 1) != '.' || strchr(ext, '/')) { + av_log(s, AV_LOG_ERROR, "The input index filename needs to have a 3 letter extension " + "to guess the associated .SUB file\n"); + return AVERROR_INVALIDDATA; + } memcpy(ext, !strncmp(ext, "IDX", 3) ? "SUB" : "sub", 3); av_log(s, AV_LOG_VERBOSE, "IDX/SUB: %s -> %s\n", s->url, vobsub->sub_name); } -- 2.17.1 _______________________________________________ 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".