Commit 784b2c48 authored Dec 04, 2020 by Dave Jiang Committed by Greg Kroah-Hartman Dec 05, 2020

driver core: auxiliary bus: Fix auxiliary bus shutdown null auxdrv ptr



If the probe of the auxdrv failed, the device->driver is set to NULL.
During kernel shutdown, the bus shutdown will call auxdrv->shutdown and
cause an invalid ptr dereference. Add check to make sure device->driver is
not NULL before we proceed.

Fixes: 7de3697e ("Add auxiliary bus support")
Cc: Dave Ertman <david.m.ertman@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/160710040926.1889434.8840329810698403478.stgit@djiang5-desk3.ch.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 5812b32e

drivers/base/auxiliary.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -92,10 +92,15 @@ static int auxiliary_bus_remove(struct device *dev)

		static void auxiliary_bus_shutdown(struct device *dev)
		{
		struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
		struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
		struct auxiliary_driver *auxdrv = NULL;
		struct auxiliary_device *auxdev;

		if (dev->driver) {
		auxdrv = to_auxiliary_drv(dev->driver);
		auxdev = to_auxiliary_dev(dev);
		}

		if (auxdrv->shutdown)
		if (auxdrv && auxdrv->shutdown)
		auxdrv->shutdown(auxdev);
		}