diff --git a/crypto/gf128mul.c b/crypto/gf128mul.c
index df35e4c..5276607 100644
--- a/crypto/gf128mul.c
+++ b/crypto/gf128mul.c
@@ -182,7 +182,7 @@ void gf128mul_lle(be128 *r, const be128 *b)
 	for (i = 0; i < 7; ++i)
 		gf128mul_x_lle(&p[i + 1], &p[i]);
 
-	memset(r, 0, sizeof(r));
+	memset(r, 0, sizeof(*r));
 	for (i = 0;;) {
 		u8 ch = ((u8 *)b)[15 - i];
 
@@ -220,7 +220,7 @@ void gf128mul_bbe(be128 *r, const be128 *b)
 	for (i = 0; i < 7; ++i)
 		gf128mul_x_bbe(&p[i + 1], &p[i]);
 
-	memset(r, 0, sizeof(r));
+	memset(r, 0, sizeof(*r));
 	for (i = 0;;) {
 		u8 ch = ((u8 *)b)[i];