diff --git a/src/md5/md5c.c b/src/md5/md5c.c
index 4dce058..cfdf97c 100644
--- a/src/md5/md5c.c
+++ b/src/md5/md5c.c
@@ -267,5 +267,5 @@ void MD5_Final(unsigned char *result, MD5_CTX *ctx)
 	result[14] = ctx->d >> 16;
 	result[15] = ctx->d >> 24;
 
-	egg_memset(ctx, 0, sizeof(ctx));
+	egg_memset(ctx, 0, sizeof(*ctx));
 }