• Mike Snitzer's avatar
    dm persistent data: handle space map checker creation failure · 62662303
    Mike Snitzer authored
    If CONFIG_DM_DEBUG_SPACE_MAPS is enabled and dm_sm_checker_create()
    fails, dm_tm_create_internal() would still return success even though it
    cleaned up all resources it was supposed to have created.  This will
    lead to a kernel crash:
    
    general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
    ...
    RIP: 0010:[<ffffffff81593659>]  [<ffffffff81593659>] dm_bufio_get_block_size+0x9/0x20
    Call Trace:
      [<ffffffff81599bae>] dm_bm_block_size+0xe/0x10
      [<ffffffff8159b8b8>] sm_ll_init+0x78/0xd0
      [<ffffffff8159c1a6>] sm_ll_new_disk+0x16/0xa0
      [<ffffffff8159c98e>] dm_sm_disk_create+0xfe/0x160
      [<ffffffff815abf6e>] dm_pool_metadata_open+0x16e/0x6a0
      [<ffffffff815aa010>] pool_ctr+0x3f0/0x900
      [<ffffffff8158d565>] dm_table_add_target+0x195/0x450
      [<ffffffff815904c4>] table_load+0xe4/0x330
      [<ffffffff815917ea>] ctl_ioctl+0x15a/0x2c0
      [<ffffffff81591963>] dm_ctl_ioctl+0x13/0x20
      [<ffffffff8116a4f8>] do_vfs_ioctl+0x98/0x560
      [<ffffffff8116aa51>] sys_ioctl+0x91/0xa0
      [<ffffffff81869f52>] system_call_fastpath+0x16/0x1b
    
    Fix the space map checker code to return an appropriate ERR_PTR and have
    dm_sm_disk_create() and dm_tm_create_internal() check for it with
    IS_ERR.
    Reported-by: default avatarVivek Goyal <vgoyal@redhat.com>
    Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
    62662303
dm-space-map-disk.c 7.12 KB