From: Iwona Winiarska iwona.winiarska@intel.com
[ Upstream commit 1c11289b34ab67ed080bbe0f1855c4938362d9cf ]
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 Link: https://lore.kernel.org/r/20220705101501.298395-1-iwona.winiarska@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/peci/cpu.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/peci/cpu.c b/drivers/peci/cpu.c index 68eb61c65d345..de4a7b3e5966e 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)