diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 78923a9f534522c7737de57f0918b81fa53a7201..8fc04b4f311f72c802a1df13af7108e3082a1b3f 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -810,11 +810,11 @@ static ssize_t kmsg_writev(struct kiocb *iocb, const struct iovec *iv,
 			   unsigned long count, loff_t pos)
 {
 	char *line, *p;
-	int len, i;
+	int i;
 	ssize_t ret = -EFAULT;
+	size_t len = iov_length(iv, count);
 
-	len = iov_length(iv, count);
-	line = p = kmalloc(len + 1, GFP_KERNEL);
+	line = kmalloc(len + 1, GFP_KERNEL);
 	if (line == NULL)
 		return -ENOMEM;
 
@@ -822,6 +822,7 @@ static ssize_t kmsg_writev(struct kiocb *iocb, const struct iovec *iv,
 	 * copy all vectors into a single string, to ensure we do
 	 * not interleave our log line with other printk calls
 	 */
+	p = line;
 	for (i = 0; i < count; i++) {
 		if (copy_from_user(p, iv[i].iov_base, iv[i].iov_len))
 			goto out;