[FFmpeg-cvslog] avcodec/wavpack: Avoid undefined shift in get_tail()

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Sun Dec 18 17:55:09 2022 +0100| [782c45cf25177db9496e6589909300b0c4ffd2ac] | committer: Michael Niedermayer

avcodec/wavpack: Avoid undefined shift in get_tail()

Fixes: left shift of 1208485947 by 1 places cannot be represented in type 'int'
Fixes: 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352

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 8374a747af247d45eb466fcb4aee90f3ae798aad)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=782c45cf25177db9496e6589909300b0c4ffd2ac
---

 libavcodec/wavpack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
index 3748ac89cc..2e51705019 100644
--- a/libavcodec/wavpack.c
+++ b/libavcodec/wavpack.c
@@ -95,7 +95,7 @@ static av_always_inline unsigned get_tail(GetBitContext *gb, int k)
     e   = (1 << (p + 1)) - k - 1;
     res = p ? get_bits(gb, p) : 0;
     if (res >= e)
-        res = (res << 1) - e + get_bits1(gb);
+        res = res * 2U - e + get_bits1(gb);
     return res;
 }