diff options
| author | Yang Yingliang <yangyingliang@huawei.com> | 2021-10-11 21:21:14 +0800 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2021-10-15 21:05:33 +0200 |
| commit | 789c1093f02c436b320d78a739f9610c8271cb73 (patch) | |
| tree | 65076af5708f1c12ef9eb2926237bb62ee30800b /include/linux/rtc.h | |
| parent | 7caadcfa8a7c6f8e754d982b99d959a222e7f863 (diff) | |
rtc: class: don't call cdev_device_del() when cdev_device_add() failed
I got a null-ptr-deref report when doing fault injection test:
general protection fault, probably for non-canonical address 0xdffffc0000000022: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000110-0x0000000000000117]
RIP: 0010:device_del+0x132/0xdc0
Call Trace:
cdev_device_del+0x1a/0x80
devm_rtc_unregister_device+0x37/0x80
release_nodes+0xc3/0x3b0
If cdev_device_add() fails, 'dev->p' is not set, it causes
null-ptr-deref when calling cdev_device_del(). Registering
character device is optional, we don't return error code
here, so introduce a new flag 'RTC_NO_CDEV' to indicate
if it has character device, cdev_device_del() is called
when this bit is not set.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211011132114.3663509-1-yangyingliang@huawei.com
Diffstat (limited to 'include/linux/rtc.h')
| -rw-r--r-- | include/linux/rtc.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/rtc.h b/include/linux/rtc.h index bd611e26291d..354e0843ab17 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -80,6 +80,7 @@ struct rtc_timer { /* flags */ #define RTC_DEV_BUSY 0 +#define RTC_NO_CDEV 1 struct rtc_device { struct device dev; |