diff --git a/verify.c b/verify.c
index 59f1ddf..c894b60 100644
--- a/verify.c
+++ b/verify.c
@@ -212,7 +212,7 @@
 {
 	void *p = io_u_verify_off(hdr, io_u, header_num);
 	struct vhdr_sha256 *vh = hdr_priv(hdr);
-	uint8_t sha256[128];
+	uint8_t sha256[64];
 	struct sha256_ctx sha256_ctx = {
 		.buf = sha256,
 	};