dm: fix use-after-free in dm_cleanup_zoned_dev()

dm_cleanup_zoned_dev() uses queue, so it must be called
before blk_cleanup_disk() starts its killing:

blk_cleanup_disk->blk_cleanup_queue()->kobject_put()->blk_release_queue()->
->...RCU...->blk_free_queue_rcu()->kmem_cache_free()

Otherwise, RCU callback may be executed first and
dm_cleanup_zoned_dev() will touch free'd memory:

 BUG: KASAN: use-after-free in dm_cleanup_zoned_dev+0x33/0xd0
 Read of size 8 at addr ffff88805ac6e430 by task dmsetup/681

 CPU: 4 PID: 681 Comm: dmsetup Not tainted 5.17.0-rc2+ #6
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x57/0x7d
  print_address_description.constprop.0+0x1f/0x150
  ? dm_cleanup_zoned_dev+0x33/0xd0
  kasan_report.cold+0x7f/0x11b
  ? dm_cleanup_zoned_dev+0x33/0xd0
  dm_cleanup_zoned_dev+0x33/0xd0
  __dm_destroy+0x26a/0x400
  ? dm_blk_ioctl+0x230/0x230
  ? up_write+0xd8/0x270
  dev_remove+0x156/0x1d0
  ctl_ioctl+0x269/0x530
  ? table_clear+0x140/0x140
  ? lock_release+0xb2/0x750
  ? remove_all+0x40/0x40
  ? rcu_read_lock_sched_held+0x12/0x70
  ? lock_downgrade+0x3c0/0x3c0
  ? rcu_read_lock_sched_held+0x12/0x70
  dm_ctl_ioctl+0xa/0x10
  __x64_sys_ioctl+0xb9/0xf0
  do_syscall_64+0x3b/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fb6dfa95c27

Fixes: bb37d77239af ("dm: introduce zone append emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 082366d..ba1068f 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1645,6 +1645,7 @@ static void cleanup_mapped_device(struct mapped_device *md)
                md->dax_dev = NULL;
        }
 
+       dm_cleanup_zoned_dev(md);
        if (md->disk) {
                spin_lock(&_minor_lock);
                md->disk->private_data = NULL;
@@ -1670,7 +1671,6 @@ static void cleanup_mapped_device(struct mapped_device *md)
        mutex_destroy(&md->swap_bios_lock);
 
        dm_mq_cleanup_mapped_device(md);
-       dm_cleanup_zoned_dev(md);
 }
 
 /*