[FFmpeg-devel] [PATCH 1/3] avcodec/bonk: Use unsigned in predictor_init_state() to avoid undefined behavior

[Michael Niedermayer]

Fixes: signed integer overflow: -5010 * -717450 cannot be represented in type 'int'
Fixes: 53370/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_BONK_fuzzer-4945644204195840

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

diff --git a/libavcodec/bonk.c b/libavcodec/bonk.c
index ebe8e46d70..df5a80b06e 100644
--- a/libavcodec/bonk.c
+++ b/libavcodec/bonk.c
@@ -277,10 +277,10 @@ static int predictor_calc_error(int *k, int *state, int order, int error)
     return x;
 }
 
-static void predictor_init_state(int *k, int *state, int order)
+static void predictor_init_state(int *k, unsigned *state, int order)
 {
     for (int i = order - 2; i >= 0; i--) {
-        int x = state[i];
+        unsigned x = state[i];
 
         for (int j = 0, p = i + 1; p < order; j++, p++) {
             int tmp = x + shift_down(k[j] * state[p], LATTICE_SHIFT);
-- 
2.17.1