[FFmpeg-cvslog] avcodec/alsdec: Fix integer overflows of raw_samples in decode_var_block_data()

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Fri Jul 26 15:37:30 2019 +0200| [ebc43bef1fc6b2ebccb57385a0ef0376be4804bc] | committer: Michael Niedermayer

avcodec/alsdec: Fix integer overflows of raw_samples in decode_var_block_data()

This also makes the code consistent with the existing similar MUL64()
in decode_var_block_data()

Fixes: signed integer overflow: -7277630735906765035 + -3272193951413647896 cannot be represented in type 'long'
Fixes: 16015/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5666552818434048

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 fad3ec89b7a664b93b5e29bdb0db0cab0272a0c4)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=ebc43bef1fc6b2ebccb57385a0ef0376be4804bc
---

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

diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c
index b8e4b3dc81..26c496c769 100644
--- a/libavcodec/alsdec.c
+++ b/libavcodec/alsdec.c
@@ -918,7 +918,7 @@ static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
             y = 1 << 6;
 
             for (base = begin; base < end; base++, tab++)
-                y += MUL64(bd->ltp_gain[tab], raw_samples[base]);
+                y += (uint64_t)MUL64(bd->ltp_gain[tab], raw_samples[base]);
 
             raw_samples[ltp_smp] += y >> 7;
         }
@@ -930,7 +930,7 @@ static int decode_var_block_data(ALSDecContext *ctx, ALSBlockData *bd)
             y = 1 << 19;
 
             for (sb = 0; sb < smp; sb++)
-                y += MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
+                y += (uint64_t)MUL64(lpc_cof[sb], raw_samples[-(sb + 1)]);
 
             *raw_samples++ -= y >> 20;
             parcor_to_lpc(smp, quant_cof, lpc_cof);