]> git.baikalelectronics.ru Git - kernel.git/commit
libnvdimm/pmem: Fix crash triggered when I/O in-flight during unbind
authorsumiyawang <sumiyawang@tencent.com>
Sun, 22 Aug 2021 11:49:09 +0000 (19:49 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 6 Oct 2021 13:42:38 +0000 (15:42 +0200)
commit4ef3447638327fad91ce5f419db728954d45b46e
tree71a62a278dc55c4c703de866fb3e3bef14b5723f
parent6619bd653d384768a67e34a3b02f9328b7944976
libnvdimm/pmem: Fix crash triggered when I/O in-flight during unbind

commit 32b2397c1e56f33b0b1881def965bb89bd12f448 upstream.

There is a use after free crash when the pmem driver tears down its
mapping while I/O is still inbound.

This is triggered by driver unbind, "ndctl destroy-namespace", while I/O
is in flight.

Fix the sequence of blk_cleanup_queue() vs memunmap().

The crash signature is of the form:

 BUG: unable to handle page fault for address: ffffc90080200000
 CPU: 36 PID: 9606 Comm: systemd-udevd
 Call Trace:
  ? pmem_do_bvec+0xf9/0x3a0
  ? xas_alloc+0x55/0xd0
  pmem_rw_page+0x4b/0x80
  bdev_read_page+0x86/0xb0
  do_mpage_readpage+0x5d4/0x7a0
  ? lru_cache_add+0xe/0x10
  mpage_readpages+0xf9/0x1c0
  ? bd_link_disk_holder+0x1a0/0x1a0
  blkdev_readpages+0x1d/0x20
  read_pages+0x67/0x1a0

  ndctl Call Trace in vmcore:
  PID: 23473  TASK: ffff88c4fbbe8000  CPU: 1   COMMAND: "ndctl"
  __schedule
  schedule
  blk_mq_freeze_queue_wait
  blk_freeze_queue
  blk_cleanup_queue
  pmem_release_queue
  devm_action_release
  release_nodes
  devres_release_all
  device_release_driver_internal
  device_driver_detach
  unbind_store

Cc: <stable@vger.kernel.org>
Signed-off-by: sumiyawang <sumiyawang@tencent.com>
Reviewed-by: yongduan <yongduan@tencent.com>
Link: https://lore.kernel.org/r/1629632949-14749-1-git-send-email-sumiyawang@tencent.com
Fixes: d067adc5a1a3 ("mm/devm_memremap_pages: fix final page put race")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[tyhicks: Minor contextual change in pmem_attach_disk() due to the
 transition to 'struct range' not yet taking place. Preserve the
 memcpy() call rather than initializing the range struct. That change
 was introduced in v5.10 with commit a4574f63edc6 ("mm/memremap_pages:
 convert to 'struct range'")]
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/nvdimm/pmem.c