linux/fs/btrfs
Josef Bacik 820a49dafc btrfs: initialize device::fs_info always
Neal reported a panic trying to use -o rescue=all

  BUG: kernel NULL pointer dereference, address: 0000000000000030
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP NOPTI
  CPU: 0 PID: 696 Comm: mount Tainted: G        W         5.12.0-rc2+ #296
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
  RIP: 0010:btrfs_device_init_dev_stats+0x1d/0x200
  RSP: 0018:ffffafaec1483bb8 EFLAGS: 00010286
  RAX: 0000000000000000 RBX: ffff9a5715bcb298 RCX: 0000000000000070
  RDX: ffff9a5703248000 RSI: ffff9a57052ea150 RDI: ffff9a5715bca400
  RBP: ffff9a57052ea150 R08: 0000000000000070 R09: ffff9a57052ea150
  R10: 000130faf0741c10 R11: 0000000000000000 R12: ffff9a5703700000
  R13: 0000000000000000 R14: ffff9a5715bcb278 R15: ffff9a57052ea150
  FS:  00007f600d122c40(0000) GS:ffff9a577bc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000030 CR3: 0000000112a46005 CR4: 0000000000370ef0
  Call Trace:
   ? btrfs_init_dev_stats+0x1f/0xf0
   ? kmem_cache_alloc+0xef/0x1f0
   btrfs_init_dev_stats+0x5f/0xf0
   open_ctree+0x10cb/0x1720
   btrfs_mount_root.cold+0x12/0xea
   legacy_get_tree+0x27/0x40
   vfs_get_tree+0x25/0xb0
   vfs_kern_mount.part.0+0x71/0xb0
   btrfs_mount+0x10d/0x380
   legacy_get_tree+0x27/0x40
   vfs_get_tree+0x25/0xb0
   path_mount+0x433/0xa00
   __x64_sys_mount+0xe3/0x120
   do_syscall_64+0x33/0x40
   entry_SYSCALL_64_after_hwframe+0x44/0xae

This happens because when we call btrfs_init_dev_stats we do
device->fs_info->dev_root.  However device->fs_info isn't initialized
because we were only calling btrfs_init_devices_late() if we properly
read the device root.  However we don't actually need the device root to
init the devices, this function simply assigns the devices their
->fs_info pointer properly, so this needs to be done unconditionally
always so that we can properly dereference device->fs_info in rescue
cases.

Reported-by: Neal Gompa <ngompa13@gmail.com>
CC: stable@vger.kernel.org # 5.11+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-03-17 19:42:12 +01:00
..
tests btrfs: extend btrfs_rmap_block for specifying a device 2021-02-09 02:46:05 +01:00
acl.c
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
backref.c btrfs: do not warn if we can't find the reloc root when looking up backref 2021-02-08 22:58:56 +01:00
backref.h btrfs: add asserts for deleting backref cache nodes 2021-02-08 22:58:56 +01:00
block-group.c btrfs: fix race between writes to swap files and scrub 2021-02-22 18:07:15 +01:00
block-group.h btrfs: fix race between writes to swap files and scrub 2021-02-22 18:07:15 +01:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
btrfs_inode.h btrfs: make btrfs_dio_private::bytes u32 2021-02-08 22:58:51 +01:00
check-integrity.c btrfs: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: make check_compressed_csum() to be subpage compatible 2021-02-22 17:15:27 +01:00
compression.h btrfs: compression: move declarations to header 2020-10-07 12:06:55 +02:00
ctree.c btrfs: fix race when cloning extent buffer during rewind of an old root 2021-03-16 20:32:17 +01:00
ctree.h btrfs: fix race between writes to swap files and scrub 2021-02-22 18:07:15 +01:00
delalloc-space.c btrfs: fix parameter description of btrfs_inode_rsv_release/btrfs_delalloc_release_space 2021-02-08 22:58:54 +01:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: don't flush from btrfs_delayed_inode_reserve_metadata 2021-03-02 17:17:09 +01:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: account for new extents being deleted in total_bytes_pinned 2021-02-08 22:58:55 +01:00
delayed-ref.h btrfs: only let one thread pre-flush delayed refs in commit 2021-02-08 22:58:56 +01:00
dev-replace.c btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
discard.c btrfs: document now parameter of peek_discard_list 2021-02-08 22:58:53 +01:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: initialize device::fs_info always 2021-03-17 19:42:12 +01:00
disk-io.h btrfs: split alloc_log_tree() 2021-02-09 02:46:07 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
extent_io.c btrfs: subpage: fix wild pointer access during metadata read failure 2021-03-16 11:06:18 +01:00
extent_io.h btrfs: zoned: redirty released extent buffers 2021-02-09 02:46:04 +01:00
extent_map.c btrfs: fix parameter description of btrfs_add_extent_mapping 2021-02-08 22:58:53 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: always pin deleted leaves when there are active tree mod log users 2021-03-16 20:32:22 +01:00
file-item.c btrfs: fix function description formats in file-item.c 2021-02-08 22:58:53 +01:00
file.c btrfs: unlock extents in btrfs_zero_range in case of quota reservation errors 2021-03-02 16:55:44 +01:00
free-space-cache.c btrfs: zoned: do not account freed region of read-only block group as zone_unusable 2021-03-04 16:16:58 +01:00
free-space-cache.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: zoned: remove outdated WARN_ON in direct IO 2021-03-17 19:41:51 +01:00
ioctl.c btrfs: validate qgroup inherit for SNAP_CREATE_V2 ioctl 2021-03-02 16:55:47 +01:00
Kconfig btrfs: switch to iomap for direct IO 2020-10-07 12:06:57 +02:00
locking.c btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00
Makefile btrfs: introduce the skeleton of btrfs_subpage structure 2021-02-08 22:59:01 +01:00
misc.h btrfs: rename tree_entry to rb_simple_node and export it 2020-05-25 11:25:19 +02:00
ordered-data.c btrfs: zoned: use ZONE_APPEND write for zoned mode 2021-02-09 02:46:06 +01:00
ordered-data.h btrfs: zoned: use ZONE_APPEND write for zoned mode 2021-02-09 02:46:06 +01:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: simplify iget helpers 2020-05-25 11:25:37 +02:00
props.h
qgroup.c btrfs: export and rename qgroup_reserve_meta 2021-03-02 16:58:30 +01:00
qgroup.h btrfs: export and rename qgroup_reserve_meta 2021-03-02 16:58:30 +01:00
raid56.c btrfs: fix raid6 qstripe kmap 2021-02-22 17:15:21 +01:00
raid56.h
rcu-string.h btrfs: rcu-string: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
reada.c btrfs: subpage: make readahead work properly 2021-03-16 11:06:21 +01:00
ref-verify.c btrfs: ref-verify: use 'inline void' keyword ordering 2021-03-02 16:55:40 +01:00
ref-verify.h
reflink.c btrfs: fix stale data exposure after cloning a hole with NO_HOLES enabled 2021-02-22 18:07:45 +01:00
reflink.h Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
relocation.c btrfs: zoned: enable relocation on a zoned filesystem 2021-02-09 02:46:07 +01:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: fix race between writes to swap files and scrub 2021-02-22 18:07:15 +01:00
send.c btrfs: send: use struct send_ctx *sctx for btrfs_compare_trees and changed_cb 2021-02-08 22:58:57 +01:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
space-info.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
struct-funcs.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
subpage.c btrfs: integrate page status update for data read path into begin/end_page_read 2021-02-08 22:59:03 +01:00
subpage.h btrfs: integrate page status update for data read path into begin/end_page_read 2021-02-08 22:59:03 +01:00
super.c btrfs: fix spurious free_space_tree remount warning 2021-03-02 16:55:55 +01:00
sysfs.c btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: zoned: redirty released extent buffers 2021-02-09 02:46:04 +01:00
transaction.h btrfs: zoned: redirty released extent buffers 2021-02-09 02:46:04 +01:00
tree-checker.c btrfs: tree-checker: do not error out if extent ref hash doesn't match 2021-02-22 18:07:44 +01:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: zoned: fix linked list corruption after log root tree allocation failure 2021-03-15 16:57:19 +01:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
volumes.c btrfs: do not initialize dev stats if we have no dev_root 2021-03-17 19:42:09 +01:00
volumes.h btrfs: zoned: relocate block group to repair IO failure in zoned filesystems 2021-02-09 02:46:07 +01:00
xattr.c btrfs: fix warning when creating a directory with smack enabled 2021-03-02 17:47:56 +01:00
xattr.h
zlib.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
zoned.c btrfs: zoned: use sector_t for zone sectors 2021-03-04 16:16:55 +01:00
zoned.h btrfs: zoned: extend zoned allocator to use dedicated tree-log block group 2021-02-09 02:46:08 +01:00
zstd.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00