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

[Katerina Barone-Adesi]

ffmpeg | branch: release/0.10 | Katerina Barone-Adesi <katerinab at gmail.com> | Tue Sep 16 01:40:24 2014 +0200| [b989bb7adee0f3286dcaa63c5cd0753eac45f6be] | 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.

(cherry picked from commit 56ac2cbd0464e0146e62c91843e2b1f5e0908504)
Signed-off-by: Diego Biurrun <diego at biurrun.de>

Conflicts:
	libavformat/apetag.c

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b989bb7adee0f3286dcaa63c5cd0753eac45f6be
---

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

diff --git a/libavformat/apetag.c b/libavformat/apetag.c
index 2390bfa..41ba054 100644
--- a/libavformat/apetag.c
+++ b/libavformat/apetag.c
@@ -51,8 +51,10 @@ 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;
+    }
     value = av_malloc(size+1);
     if (!value)
         return AVERROR(ENOMEM);