diff mbox

[v2,4/5] mailbox: mailbox-test: Prevent memory leak

Message ID 1458744223-12164-5-git-send-email-lee.jones@linaro.org
State Accepted
Commit d1c2f87c9a8f79fa8816bbe7de98da38eae2be5e
Headers show

Commit Message

Lee Jones March 23, 2016, 2:43 p.m. UTC
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>

---
 drivers/mailbox/mailbox-test.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

-- 
1.9.1
diff mbox

Patch

diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index 5f4b439..58d0472 100644
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -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);