[FFmpeg-devel] [PATCH 2/4] avcodec/agm: Fix overflow of signed shift

Michael Niedermayer michael at niedermayer.cc
Mon Jul 1 01:16:49 EEST 2019


Fixes: left shift of 1 by 31 places cannot be represented in type 'int'
Fixes: 15328/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AGM_fuzzer-5637545171353600

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/agm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/agm.c b/libavcodec/agm.c
index a499c09082..2c4c9805e9 100644
--- a/libavcodec/agm.c
+++ b/libavcodec/agm.c
@@ -918,7 +918,7 @@ static void get_tree_codes(uint32_t *codes, Node *nodes, int idx, uint32_t pfx,
         codes[idx] = pfx;
     } else if (idx >= 0) {
         get_tree_codes(codes, nodes, nodes[idx].child[0], pfx + (0 << bitpos), bitpos + 1);
-        get_tree_codes(codes, nodes, nodes[idx].child[1], pfx + (1 << bitpos), bitpos + 1);
+        get_tree_codes(codes, nodes, nodes[idx].child[1], pfx + (1U << bitpos), bitpos + 1);
     }
 }
 
-- 
2.22.0



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