mailbox: Off by one in mbox_test_message_read()

We need to leave space for the NUL char.

Fixes: 8ea4484d0c2b ('mailbox: Add generic mechanism for testing Mailbox Controllers')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index a4f10cc4aea3..f82dc8926687 100644
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -143,7 +143,7 @@ static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf,
         int l = 0;
         int ret;
 
-        touser = kzalloc(MBOX_HEXDUMP_MAX_LEN, GFP_KERNEL);
+        touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
         if (!touser)
                 return -ENOMEM;