diff --git a/drivers/char/random.c b/drivers/char/random.c
index e1d41b8a1d36..eb2e8a5d8a66 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -550,7 +550,7 @@ static void _mix_pool_bytes(struct entropy_store *r, const void *in,
 	unsigned long i, tap1, tap2, tap3, tap4, tap5;
 	int input_rotate;
 	int wordmask = r->poolinfo->poolwords - 1;
-	const char *bytes = in;
+	const unsigned char *bytes = in;
 	__u32 w;
 
 	tap1 = r->poolinfo->tap1;