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driver: core: Fix list corruption after device_del()
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commit 66482f6 upstream.

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: e2ae9bc ("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>
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tiwai authored and gregkh committed Dec 30, 2020
1 parent 0c500d6 commit c260623
Showing 1 changed file with 1 addition and 1 deletion.
2 changes: 1 addition & 1 deletion drivers/base/core.c
Expand Up @@ -1386,7 +1386,7 @@ 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);

/*
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