[FFmpeg-cvslog] avcodec/bintext: sanity check dimensions

[Michael Niedermayer]

ffmpeg | branch: release/3.0 | Michael Niedermayer <michael at niedermayer.cc> | Mon Feb 26 21:17:08 2018 +0100| [add3c2468e960767c7fc7232ab8a492f8c55e65b] | committer: Michael Niedermayer

avcodec/bintext: sanity check dimensions

Fixes: Timeout
Fixes: 6277/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_XBIN_fuzzer-6047202288861184

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 090c0abff9c8b27304614f15d9464dbf4ea59833)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=add3c2468e960767c7fc7232ab8a492f8c55e65b
---

 libavcodec/bintext.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/libavcodec/bintext.c b/libavcodec/bintext.c
index 90bbe67b59..d967317671 100644
--- a/libavcodec/bintext.c
+++ b/libavcodec/bintext.c
@@ -35,6 +35,8 @@
 #include "bintext.h"
 #include "internal.h"
 
+#define FONT_WIDTH 8
+
 typedef struct XbinContext {
     AVFrame *frame;
     int palette[16];
@@ -91,6 +93,9 @@ static av_cold int decode_init(AVCodecContext *avctx)
             break;
         }
     }
+    if (avctx->width < FONT_WIDTH || avctx->height < s->font_height)
+        return AVERROR_INVALIDDATA;
+
 
     s->frame = av_frame_alloc();
     if (!s->frame)
@@ -113,8 +118,6 @@ av_unused static void hscroll(AVCodecContext *avctx)
     }
 }
 
-#define FONT_WIDTH 8
-
 /**
  * Draw character to screen
  */