driver core: Avoid binding drivers to dead devices
authorLukas Wunner <lukas@wunner.de>
Wed, 8 Jul 2020 13:27:01 +0000 (15:27 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 21 Aug 2020 11:07:26 +0000 (13:07 +0200)
commit45274806f28da5d87dae2a056325bab97d164351
tree853525235b33428629f9279e4e0e716a2da840e4
parent7b897c98b23ebf3258492c6f61a4ea22bd5939f6
driver core: Avoid binding drivers to dead devices

commit 654888327e9f655a9d55ad477a9583e90e8c9b5c upstream.

Commit 3451a495ef24 ("driver core: Establish order of operations for
device_add and device_del via bitflag") sought to prevent asynchronous
driver binding to a device which is being removed.  It added a
per-device "dead" flag which is checked in the following code paths:

* asynchronous binding in __driver_attach_async_helper()
*  synchronous binding in device_driver_attach()
* asynchronous binding in __device_attach_async_helper()

It did *not* check the flag upon:

*  synchronous binding in __device_attach()

However __device_attach() may also be called asynchronously from:

deferred_probe_work_func()
  bus_probe_device()
    device_initial_probe()
      __device_attach()

So if the commit's intention was to check the "dead" flag in all
asynchronous code paths, then a check is also necessary in
__device_attach().  Add the missing check.

Fixes: 3451a495ef24 ("driver core: Establish order of operations for device_add and device_del via bitflag")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v5.1+
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/de88a23a6fe0ef70f7cfd13c8aea9ab51b4edab6.1594214103.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/base/dd.c