diff options
author | Dan Carpenter <dan.carpenter@linaro.org> | 2023-05-05 12:22:09 +0300 |
---|---|---|
committer | Jassi Brar <jaswinder.singh@linaro.org> | 2023-05-31 13:26:44 -0500 |
commit | 8fe72b76db79d694858e872370df49676bc3be8c (patch) | |
tree | ec9258209d71992eaf76b2c9368a0dfdecda155a /drivers/mailbox | |
parent | 884fe9da1b7ccbea31b118f902fbc78f58366b4a (diff) | |
download | lwn-8fe72b76db79d694858e872370df49676bc3be8c.tar.gz lwn-8fe72b76db79d694858e872370df49676bc3be8c.zip |
mailbox: mailbox-test: fix a locking issue in mbox_test_message_write()
There was a bug where this code forgot to unlock the tdev->mutex if the
kzalloc() failed. Fix this issue, by moving the allocation outside the
lock.
Fixes: 2d1e952a2b8e ("mailbox: mailbox-test: Fix potential double-free in mbox_test_message_write()")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Lee Jones <lee@kernel.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Diffstat (limited to 'drivers/mailbox')
-rw-r--r-- | drivers/mailbox/mailbox-test.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index c4a705c30331..fc6a12a51b40 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -98,6 +98,7 @@ static ssize_t mbox_test_message_write(struct file *filp, size_t count, loff_t *ppos) { struct mbox_test_device *tdev = filp->private_data; + char *message; void *data; int ret; @@ -113,12 +114,13 @@ static ssize_t mbox_test_message_write(struct file *filp, return -EINVAL; } - mutex_lock(&tdev->mutex); - - tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL); - if (!tdev->message) + message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL); + if (!message) return -ENOMEM; + mutex_lock(&tdev->mutex); + + tdev->message = message; ret = copy_from_user(tdev->message, userbuf, count); if (ret) { ret = -EFAULT; |