Fix segfault in loose_backend__readstream

If the routine exits with error before stream or hash_ctx is initialized, the
program will segfault when trying to free them.

1 files changed, 10 insertions, 5 deletions

diff --git a/src/odb_loose.c b/src/odb_loose.c
index c37b1eda2..5872a25b3 100644
--- a/src/odb_loose.c
+++ b/src/odb_loose.c
@@ -1028,11 +1028,16 @@ static int loose_backend__readstream(
 
 done:
 	if (error < 0) {
-		git_futils_mmap_free(&stream->map);
-		git_zstream_free(&stream->zstream);
-		git_hash_ctx_cleanup(hash_ctx);
-		git__free(hash_ctx);
-		git__free(stream);
+                if(stream && stream->map.data)
+		        git_futils_mmap_free(&stream->map);
+                if(stream)
+   		        git_zstream_free(&stream->zstream);
+                if(stream)
+                        git__free(stream);
+                if(hash_ctx) {
+   		        git_hash_ctx_cleanup(hash_ctx);
+		        git__free(hash_ctx);
+                }
 	}
 
 	git_buf_dispose(&object_path);