[FFmpeg-cvslog] avcodec/apedec: Fix 2 integer overflows

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Thu Nov 14 16:38:36 2019 +0100| [1d7226ee65046e9261d36db00e33c7b7833e9fa2] | committer: Michael Niedermayer

avcodec/apedec: Fix 2 integer overflows

Fixes: signed integer overflow: 2119056926 - -134217728 cannot be represented in type 'int'
Fixes: 18728/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APE_fuzzer-5747539563511808

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 6e15ba2d1f688c61759001839811b11903de9ce0)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1d7226ee65046e9261d36db00e33c7b7833e9fa2
---

 libavcodec/apedec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/apedec.c b/libavcodec/apedec.c
index 310ef3037f..cd9b5476b9 100644
--- a/libavcodec/apedec.c
+++ b/libavcodec/apedec.c
@@ -1230,7 +1230,7 @@ static void predictor_decode_mono_3950(APEContext *ctx, int count)
             p->buf = p->historybuffer;
         }
 
-        p->filterA[0] = currentA + ((int)(p->filterA[0] * 31U) >> 5);
+        p->filterA[0] = currentA + (unsigned)((int)(p->filterA[0] * 31U) >> 5);
         *(decoded0++) = p->filterA[0];
     }
 
@@ -1290,7 +1290,7 @@ static void do_apply_filter(APEContext *ctx, int version, APEFilter *f,
             else
                 *f->adaptcoeffs = 0;
 
-            f->avg += (absres - f->avg) / 16;
+            f->avg += (int)(absres - (unsigned)f->avg) / 16;
 
             f->adaptcoeffs[-1] >>= 1;
             f->adaptcoeffs[-2] >>= 1;