| diff --git a/third_party/zlib/deflate.c b/third_party/zlib/deflate.c |
| index a39e62787862..c6053fd1c7ea 100644 |
| --- a/third_party/zlib/deflate.c |
| +++ b/third_party/zlib/deflate.c |
| @@ -318,6 +318,10 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy, |
| s->w_size + window_padding, |
| 2*sizeof(Byte)); |
| s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); |
| + /* Avoid use of uninitialized value, see: |
| + * https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11360 |
| + */ |
| + zmemzero(s->prev, s->w_size * sizeof(Pos)); |
| s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); |
| |
| s->high_water = 0; /* nothing written to s->window yet */ |
