From 1e689518d508b96f2a6a6f3bbbb43f00eaf87d01 Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Mon, 18 May 2020 04:43:25 +0200 Subject: [PATCH] avformat/webmdashenc: Don't segfault on invalid arguments The current parsing process for adaptation_sets does not guarantee every adaptation set to contain at least one stream, because the loop exits immediately as soon as the end of the string has been reached, without checking whether the currently active adaptation set group is lacking a stream. This would lead to segfaults lateron as the rest of the code presumed that every adaptation set contains a stream. This commit fixes this by erroring out when the last adaptation set group is incomplete. Signed-off-by: Andreas Rheinhardt --- libavformat/webmdashenc.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/libavformat/webmdashenc.c b/libavformat/webmdashenc.c index fd07b3e34a..3101e0a039 100644 --- a/libavformat/webmdashenc.c +++ b/libavformat/webmdashenc.c @@ -437,8 +437,13 @@ static int parse_adaptation_sets(AVFormatContext *s) } // syntax id=0,streams=0,1,2 id=1,streams=3,4 and so on state = new_set; - while (p < w->adaptation_sets + strlen(w->adaptation_sets)) { - if (state == new_set && *p == ' ') { + while (1) { + if (*p == '\0') { + if (state == new_set) + break; + else + return AVERROR(EINVAL); + } else if (state == new_set && *p == ' ') { p++; continue; } else if (state == new_set && !strncmp(p, "id=", 3)) {