[FFmpeg-cvslog] mjpeg: Check for interlaced progressive frames

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Fri Mar  2 21:35:58 2012 +0100| [a3f5ee297a7cf9bf21646ec4858d614f36248ff7] | committer: Michael Niedermayer

mjpeg: Check for interlaced progressive frames

Fixes null pointer dereference.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=a3f5ee297a7cf9bf21646ec4858d614f36248ff7
---

 libavcodec/mjpegdec.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index dac0d67..0a9d030 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -312,8 +312,13 @@ int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
         s->first_picture = 0;
     }
 
-    if (s->interlaced && (s->bottom_field == !s->interlace_polarity))
+    if (s->interlaced && (s->bottom_field == !s->interlace_polarity)) {
+        if (s->progressive) {
+            av_log_ask_for_sample(s->avctx, "progressively coded interlaced pictures not supported\n");
+            return AVERROR_INVALIDDATA;
+        }
         return 0;
+    }
 
     /* XXX: not complete test ! */
     pix_fmt_id = (s->h_count[0] << 28) | (s->v_count[0] << 24) |