apetag: Fix APE tag size check

Message ID 20140917140150.B30AF5DE01@aruru.libav.org
State New
Headers show

Commit Message

Janne Grunau Sept. 17, 2014, 2:01 p.m.
Module: libav
Branch: master
Commit: c5560e72d0bb69f8a1ac9536570398f84388f396

Author:    Katerina Barone-Adesi <katerinab@gmail.com>
Committer: Diego Biurrun <diego@biurrun.de>
Date:      Tue Sep 16 01:40:24 2014 +0200

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@libav.org
Signed-off-by: Diego Biurrun <diego@biurrun.de>

---

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

Patch

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;