From 654888327e9f655a9d55ad477a9583e90e8c9b5c Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Wed, 8 Jul 2020 15:27:01 +0200 Subject: [PATCH] driver core: Avoid binding drivers to dead devices 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 Cc: stable@vger.kernel.org # v5.1+ Cc: Alexander Duyck Link: https://lore.kernel.org/r/de88a23a6fe0ef70f7cfd13c8aea9ab51b4edab6.1594214103.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/base/dd.c b/drivers/base/dd.c index fce8e35b6367..b29faa24eef8 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -864,7 +864,9 @@ static int __device_attach(struct device *dev, bool allow_async) int ret = 0; device_lock(dev); - if (dev->driver) { + if (dev->p->dead) { + goto out_unlock; + } else if (dev->driver) { if (device_is_bound(dev)) { ret = 1; goto out_unlock;