diff --git a/cmd/ztest.c b/cmd/ztest.c
index dc8ac85b6991..35929cbcfffb 100644
--- a/cmd/ztest.c
+++ b/cmd/ztest.c
@@ -8143,7 +8143,7 @@ ztest_raidz_expand_run(ztest_shared_t *zs, spa_t *spa)
 	/* Setup a 1 MiB buffer of random data */
 	uint64_t bufsize = 1024 * 1024;
 	void *buffer = umem_alloc(bufsize, UMEM_NOFAIL);
-	random_get_pseudo_bytes((uint8_t *)&buffer, bufsize);
+	random_get_pseudo_bytes((uint8_t *)buffer, bufsize);
 
 	/*
 	 * Put some data in the pool and then attach a vdev to initiate