diff --git a/sys/kern/kern_ktrace.c b/sys/kern/kern_ktrace.c
index e6d3b87ed82a..73905c352a5b 100644
--- a/sys/kern/kern_ktrace.c
+++ b/sys/kern/kern_ktrace.c
@@ -1327,6 +1327,8 @@ ktrwrite(struct ktr_desc *ktd, struct ktrace_entry *kte)
 	struct ktr_header *kth;
 	file_t *fp = ktd->ktd_fp;
 	int error;
+
+	memset(&auio, 0, sizeof(auio));
 next:
 	auio.uio_iov = iov = &aiov[0];
 	auio.uio_offset = 0;