pack: check pack_window_open return
diff --git a/src/pack.c b/src/pack.c
index d9e8bf2..71d321a 100644
--- a/src/pack.c
+++ b/src/pack.c
@@ -844,7 +844,10 @@ static int packfile_unpack_compressed(
unsigned int window_len;
unsigned char *in;
- in = pack_window_open(p, mwindow, *position, &window_len);
+ if ((in = pack_window_open(p, mwindow, *position, &window_len)) == NULL) {
+ error = -1;
+ goto out;
+ }
if ((error = git_zstream_set_input(&zstream, in, window_len)) < 0 ||
(error = git_zstream_get_output_chunk(data + total, &bytes, &zstream)) < 0) {