scsi: core: check for device state in __scsi_remove_target()
authorHannes Reinecke <hare@suse.de>
Wed, 13 Dec 2017 13:21:37 +0000 (14:21 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 22 Feb 2018 14:42:31 +0000 (15:42 +0100)
commit 81b6c999897919d5a16fedc018fe375dbab091c5 upstream.

As it turned out device_get() doesn't use kref_get_unless_zero(), so we
will be always getting a device pointer.  Consequently, we need to check
for the device state in __scsi_remove_target() to avoid tripping over
deleted objects.

Fixes: fbce4d97fd43 ("scsi: fixup kernel warning during rmmod()")
Reported-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Max Ivanov <ivanov.maxim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/scsi/scsi_sysfs.c

index f796bd6..40406c1 100644 (file)
@@ -1383,7 +1383,10 @@ static void __scsi_remove_target(struct scsi_target *starget)
                 * check.
                 */
                if (sdev->channel != starget->channel ||
-                   sdev->id != starget->id ||
+                   sdev->id != starget->id)
+                       continue;
+               if (sdev->sdev_state == SDEV_DEL ||
+                   sdev->sdev_state == SDEV_CANCEL ||
                    !get_device(&sdev->sdev_gendev))
                        continue;
                spin_unlock_irqrestore(shost->host_lock, flags);