mailbox: mailbox-test: Prevent memory leak

If we set the Signal twice or more, without using it as part of a message,
memory will be re-allocated and the pointer over-written.  Prevent this
potential leak by only allocating memory when there isn't any already.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
This commit is contained in:
Lee Jones 2016-03-23 14:43:42 +00:00 committed by Jassi Brar
parent 17f5f28ffa
commit d1c2f87c9a

View File

@ -59,9 +59,12 @@ static ssize_t mbox_test_signal_write(struct file *filp,
return -EINVAL;
}
tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
if (!tdev->signal)
return -ENOMEM;
/* Only allocate memory if we need to */
if (!tdev->signal) {
tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
if (!tdev->signal)
return -ENOMEM;
}
if (copy_from_user(tdev->signal, userbuf, count)) {
kfree(tdev->signal);