[FFmpeg-devel] [PATCH 4/4] avcodec/sonic: Check channels before deallocating

[Michael Niedermayer]

Fixes: heap-buffer-overflow
Fixes: 25744/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SONIC_fuzzer-5172961169113088

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/sonic.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/libavcodec/sonic.c b/libavcodec/sonic.c
index fa4ecc3a7a..d09de6156b 100644
--- a/libavcodec/sonic.c
+++ b/libavcodec/sonic.c
@@ -980,12 +980,11 @@ static av_cold int sonic_decode_close(AVCodecContext *avctx)
     av_freep(&s->int_samples);
     av_freep(&s->tap_quant);
     av_freep(&s->predictor_k);
-
-    for (i = 0; i < s->channels; i++)
-    {
-        av_freep(&s->predictor_state[i]);
-        av_freep(&s->coded_samples[i]);
-    }
+    if (s->channels <= MAX_CHANNELS)
+        for (i = 0; i < s->channels; i++) {
+            av_freep(&s->predictor_state[i]);
+            av_freep(&s->coded_samples[i]);
+        }
 
     return 0;
 }
-- 
2.17.1