| Message ID | 20220705101501.298395-1-iwona.winiarska@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | peci: cpu: Fix use-after-free in adev_release() | expand |
diff --git a/drivers/peci/cpu.c b/drivers/peci/cpu.c index 68eb61c65d34..de4a7b3e5966 100644 --- a/drivers/peci/cpu.c +++ b/drivers/peci/cpu.c @@ -188,8 +188,6 @@ static void adev_release(struct device *dev) { struct auxiliary_device *adev = to_auxiliary_dev(dev); - auxiliary_device_uninit(adev); - kfree(adev->name); kfree(adev); } @@ -234,6 +232,7 @@ static void unregister_adev(void *_adev) struct auxiliary_device *adev = _adev; auxiliary_device_delete(adev); + auxiliary_device_uninit(adev); } static int devm_adev_add(struct device *dev, int idx)
When auxiliary_device_add() returns an error, auxiliary_device_uninit() is called, which causes refcount for device to be decremented and .release callback will be triggered. Because adev_release() re-calls auxiliary_device_uninit(), it will cause use-after-free: [ 1269.455172] WARNING: CPU: 0 PID: 14267 at lib/refcount.c:28 refcount_warn_saturate+0x110/0x15 [ 1269.464007] refcount_t: underflow; use-after-free. Reported-by: Jianglei Nie <niejianglei2021@163.com> Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com> --- drivers/peci/cpu.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)