According to the include/linux/watchdog.h WDIOC_SETOPTIONS is classified as 'read from device' ioctl call: #define WDIOC_SETOPTIONS _IOR(WATCHDOG_IOCTL_BASE, 4, int) However, the driver 'mpcore_wdt' performs 'copy_from_user' only if _IOC_WRITE is set, thus the local variable 'uarg' which is used in WDIOC_SETOPTIONS handling remains uninitialized. The proper way to fix this is to bind WDIOC_SETOPTIONS to _IOW, but this will break compatibility. So adding additional condition for performing 'copy_from_user'. Signed-off-by: Vitaly Kuzmichev --- drivers/watchdog/mpcore_wdt.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) --- a/drivers/watchdog/mpcore_wdt.c +++ b/drivers/watchdog/mpcore_wdt.c @@ -235,7 +235,8 @@ static long mpcore_wdt_ioctl(struct file if (_IOC_DIR(cmd) && _IOC_SIZE(cmd) > sizeof(uarg)) return -ENOTTY; - if (_IOC_DIR(cmd) & _IOC_WRITE) { + if ((_IOC_DIR(cmd) & _IOC_WRITE) + || cmd == WDIOC_SETOPTIONS) { ret = copy_from_user(&uarg, (void __user *)arg, _IOC_SIZE(cmd)); if (ret) return -EFAULT;