[SCM] libav/wheezy-security: alac: Limit max_samples_per_frame

[siretart at users.alioth.debian.org]

The following commit has been merged in the wheezy-security branch:
commit 110680c5a2098505400f4fdff4c994020a377d19
Author: Martin Storsjö <martin at martin.st>
Date:   Tue Sep 3 11:54:03 2013 +0300

    alac: Limit max_samples_per_frame
    
    Otherwise buffer size calculations in allocate_buffers could
    overflow later, making the code think a large enough buffer
    actually was allocated.
    
    Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
    CC: libav-stable at libav.org
    Signed-off-by: Martin Storsjö <martin at martin.st>

diff --git a/libavcodec/alac.c b/libavcodec/alac.c
index da78908..23b8951 100644
--- a/libavcodec/alac.c
+++ b/libavcodec/alac.c
@@ -584,6 +584,12 @@ static int alac_set_info(ALACContext *alac)
 
     /* buffer size / 2 ? */
     alac->setinfo_max_samples_per_frame = bytestream_get_be32(&ptr);
+    if (!alac->setinfo_max_samples_per_frame ||
+        alac->setinfo_max_samples_per_frame > INT_MAX / sizeof(int32_t)) {
+        av_log(alac->avctx, AV_LOG_ERROR, "max samples per frame invalid: %u\n",
+               alac->setinfo_max_samples_per_frame);
+        return AVERROR_INVALIDDATA;
+    }
     ptr++;                          /* compatible version */
     alac->setinfo_sample_size           = *ptr++;
     alac->setinfo_rice_historymult      = *ptr++;

-- 
Libav/FFmpeg packaging