On Wed, 11 Sep 2013, Luca Barbato wrote:

On 11/09/13 22:47, Martin Storsjö wrote:
Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: [email protected]
---
 libavformat/sierravmd.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/libavformat/sierravmd.c b/libavformat/sierravmd.c
index 645b99b..8915001 100644
--- a/libavformat/sierravmd.c
+++ b/libavformat/sierravmd.c
@@ -199,6 +199,10 @@ static int vmd_read_header(AVFormatContext *s)
             avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
             type = chunk[0];
             size = AV_RL32(&chunk[2]);
+            if (size > INT_MAX/2) {
                               ^^^ spaces

Why INT_MAX / 2 btw?

Because we need to be sure that size + BYTES_PER_FRAME_RECORD doesn't wrap. We could explicitly check for INT_MAX - BYTES_PER_FRAME_RECORD, but INT_MAX / 2 gives a bit more marginal since it really shouldn't be all that big mostly anyway (Kostya suggested this for another patch earlier today, http://patches.libav.org/patch/42128/).

I amended this one as well to add spaces around the operator.

// Martin
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