[FFmpeg-cvslog] apetag: Fix APE tag size check

[Katerina Barone-Adesi]

ffmpeg | branch: master | Katerina Barone-Adesi <katerinab at gmail.com> | Tue Sep 16 01:40:24 2014 +0200| [c5560e72d0bb69f8a1ac9536570398f84388f396] | committer: Diego Biurrun

apetag: Fix APE tag size check

The size variable is (correctly) unsigned, but is passed to several functions
which take signed parameters, such as avio_read, sometimes after having
numbers added to it. So ensure that size remains within the bounds that
these functions can handle.

CC: libav-stable at libav.org
Signed-off-by: Diego Biurrun <diego at biurrun.de>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c5560e72d0bb69f8a1ac9536570398f84388f396
---

 libavformat/apetag.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libavformat/apetag.c b/libavformat/apetag.c
index 22884ef..bd8d0ed 100644
--- a/libavformat/apetag.c
+++ b/libavformat/apetag.c
@@ -57,8 +57,10 @@ static int ape_tag_read_field(AVFormatContext *s)
         av_log(s, AV_LOG_WARNING, "Invalid APE tag key '%s'.\n", key);
         return -1;
     }
-    if (size >= UINT_MAX)
-        return -1;
+    if (size > INT32_MAX - FF_INPUT_BUFFER_PADDING_SIZE) {
+        av_log(s, AV_LOG_ERROR, "APE tag size too large.\n");
+        return AVERROR_INVALIDDATA;
+    }
     if (flags & APE_TAG_FLAG_IS_BINARY) {
         uint8_t filename[1024];
         enum AVCodecID id;