From d381249bb86d5a4b1a99bb292a7aed034d6d12de Mon Sep 17 00:00:00 2001
From: Daniel Kang <daniel.d.kang@gmail.com>
Date: Thu, 6 Jan 2011 22:12:55 +0000
Subject: [PATCH] Fix a crash when decoding tiff by moving check for invalid
 header up before reading data. Fixes issue 2500.

Patch by Daniel Kang, daniel.d.kang at gmail

Originally committed as revision 26248 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/tiff.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index a23af1ab6f..c1b71dc99a 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -263,6 +263,10 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start, const uint8_t *
         s->height = value;
         break;
     case TIFF_BPP:
+        if(count > 4){
+            av_log(s->avctx, AV_LOG_ERROR, "This format is not supported (bpp=%d, %d components)\n", s->bpp, count);
+            return -1;
+        }
         if(count == 1) s->bpp = value;
         else{
             switch(type){
@@ -278,10 +282,6 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start, const uint8_t *
                 s->bpp = -1;
             }
         }
-        if(count > 4){
-            av_log(s->avctx, AV_LOG_ERROR, "This format is not supported (bpp=%d, %d components)\n", s->bpp, count);
-            return -1;
-        }
         switch(s->bpp*10 + count){
         case 11:
             s->avctx->pix_fmt = PIX_FMT_MONOBLACK;