This is a note to let you know that I've just added the patch titled

driver: core: Fix list corruption after device_del()

to my driver-core git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git in the driver-core-testing branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will be merged to the driver-core-next branch sometime soon, after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.

From 66482f640755b31cb94371ff6cef17400cda6db5 Mon Sep 17 00:00:00 2001

From: Takashi Iwai tiwai@suse.de Date: Tue, 8 Dec 2020 20:03:26 +0100 Subject: driver: core: Fix list corruption after device_del()

The device_links_purge() function (called from device_del()) tries to remove the links.needs_suppliers list entry, but it's using list_del(), hence it doesn't initialize after the removal. This is OK for normal cases where device_del() is called via device_destroy(). However, it's not guaranteed that the device object will be really deleted soon after device_del(). In a minor case like HD-audio codec reconfiguration that re-initializes the device after device_del(), it may lead to a crash by the corrupted list entry.

As a simple fix, replace list_del() with list_del_init() in order to make the list intact after the device_del() call.

Fixes: e2ae9bcc4aaa ("driver core: Add support for linking devices during device addition") Cc: stable@vger.kernel.org Reviewed-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Takashi Iwai tiwai@suse.de Link: https://lore.kernel.org/r/20201208190326.27531-1-tiwai@suse.de Cc: Saravana Kannan saravanak@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/base/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c index 1165a80f8010..ba5a3cac6571 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1384,7 +1384,7 @@ static void device_links_purge(struct device *dev) return;

mutex_lock(&wfs_lock); - list_del(&dev->links.needs_suppliers); + list_del_init(&dev->links.needs_suppliers); mutex_unlock(&wfs_lock);

/*