Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2024-12-29 09:12:07 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

chardev: fix error handling in cdev_device_add()

Browse Source 
While doing fault injection test, I got the following report:

------------[ cut here ]------------
kobject: '(null)' (0000000039956980): is not initialized, yet kobject_put() is being called.
WARNING: CPU: 3 PID: 6306 at kobject_put+0x23d/0x4e0
CPU: 3 PID: 6306 Comm: 283 Tainted: G        W          6.1.0-rc2-00005-g307c1086d7c9 #1253
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:kobject_put+0x23d/0x4e0
Call Trace:
 <TASK>
 cdev_device_add+0x15e/0x1b0
 __iio_device_register+0x13b4/0x1af0 [industrialio]
 __devm_iio_device_register+0x22/0x90 [industrialio]
 max517_probe+0x3d8/0x6b4 [max517]
 i2c_device_probe+0xa81/0xc00

When device_add() is injected fault and returns error, if dev->devt is not set,
cdev_add() is not called, cdev_del() is not needed. Fix this by checking dev->devt
in error path.

Fixes: 233ed09d7f ("chardev: add helper function to register char devs with a struct device")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221202030237.520280-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yang Yingliang 2022-12-02 11:02:37 +08:00 committed by Greg Kroah-Hartman
parent 728ac33892
commit 11fa7fefe3
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/char_dev.c
View File

@ -554,7 +554,7 @@ int cdev_device_add(struct cdev *cdev, struct device *dev)
}
rc = device_add(dev);
if (rc)
if (rc && dev->devt)
cdev_del(cdev);
return rc;