[FFmpeg-cvslog] avcodec/ivi: Move buffer/block end check to caller of ivi_dc_transform()

[Michael Niedermayer]

ffmpeg | branch: release/3.2 | Michael Niedermayer <michael at niedermayer.cc> | Fri Apr 12 00:09:57 2019 +0200| [3b2994552a9882b54c34a401b0f89078c7474b0b] | committer: Michael Niedermayer

avcodec/ivi: Move buffer/block end check to caller of ivi_dc_transform()

Fixes: assertion failure
Fixes: 14078/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_INDEO5_fuzzer-5760571284127744

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 110dce96331529a13cc815d3c852aed9d37f83d0)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3b2994552a9882b54c34a401b0f89078c7474b0b
---

 libavcodec/ivi.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/libavcodec/ivi.c b/libavcodec/ivi.c
index 70f08a8503..993b0196f4 100644
--- a/libavcodec/ivi.c
+++ b/libavcodec/ivi.c
@@ -488,12 +488,6 @@ static int ivi_dec_tile_data_size(GetBitContext *gb)
 static int ivi_dc_transform(IVIBandDesc *band, int *prev_dc, int buf_offs,
                             int blk_size)
 {
-    int buf_size = band->pitch * band->aheight - buf_offs;
-    int min_size = (blk_size - 1) * band->pitch + blk_size;
-
-    if (min_size > buf_size)
-        return AVERROR_INVALIDDATA;
-
     band->dc_transform(prev_dc, band->buf + buf_offs,
                        band->pitch, blk_size);
 
@@ -724,6 +718,11 @@ static int ivi_decode_blocks(GetBitContext *gb, IVIBandDesc *band,
                 if (ret < 0)
                     return ret;
             } else {
+                int buf_size = band->pitch * band->aheight - buf_offs;
+                int min_size = (blk_size - 1) * band->pitch + blk_size;
+
+                if (min_size > buf_size)
+                    return AVERROR_INVALIDDATA;
                 /* block not coded */
                 /* for intra blocks apply the dc slant transform */
                 /* for inter - perform the motion compensation without delta */