Btrfs: fix use-after-free problem of the device during device replace
The problem is: Task0(device scan task) Task1(device replace task) scan_one_device() mutex_lock(&uuid_mutex) device = find_device() mutex_lock(&device_list_mutex) lock_chunk() rm_and_free_source_device unlock_chunk() mutex_unlock(&device_list_mutex) check device Destroying the target device if device replace fails also has the same problem. We fix this problem by locking uuid_mutex during destroying source device or target device, just like the device remove operation. It is a temporary solution, we can fix this problem and make the code more clear by atomic counter in the future. Signed-off-by:Miao Xie <miaox@cn.fujitsu.com> Signed-off-by:
Chris Mason <clm@fb.com>
parent
adbbb863
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