linux/fs
Minchan Kim ad8d869343 kernfs: fix NULL dereferencing in kernfs_remove
kernfs_remove supported NULL kernfs_node param to bail out but revent
per-fs lock change introduced regression that dereferencing the
param without NULL check so kernel goes crash.

This patch checks the NULL kernfs_node in kernfs_remove and if so,
just return.

Quote from bug report by Jirka

```
The bug is triggered by running NAS Parallel benchmark suite on
SuperMicro servers with 2x Xeon(R) Gold 6126 CPU. Here is the error
log:

[  247.035564] BUG: kernel NULL pointer dereference, address: 0000000000000008
[  247.036009] #PF: supervisor read access in kernel mode
[  247.036009] #PF: error_code(0x0000) - not-present page
[  247.036009] PGD 0 P4D 0
[  247.036009] Oops: 0000 [#1] PREEMPT SMP PTI
[  247.058060] CPU: 1 PID: 6546 Comm: umount Not tainted
5.16.0393c3714081a53795bbff0e985d24146def6f57f+ #16
[  247.058060] Hardware name: Supermicro Super Server/X11DDW-L, BIOS
2.0b 03/07/2018
[  247.058060] RIP: 0010:kernfs_remove+0x8/0x50
[  247.058060] Code: 4c 89 e0 5b 5d 41 5c 41 5d 41 5e c3 49 c7 c4 f4
ff ff ff eb b2 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1f 44 00 00
41 54 55 <48> 8b 47 08 48 89 fd 48 85 c0 48 0f 44 c7 4c 8b 60 50 49 83
c4 60
[  247.058060] RSP: 0018:ffffbbfa48a27e48 EFLAGS: 00010246
[  247.058060] RAX: 0000000000000001 RBX: ffffffff89e31f98 RCX: 0000000080200018
[  247.058060] RDX: 0000000080200019 RSI: fffff6760786c900 RDI: 0000000000000000
[  247.058060] RBP: ffffffff89e31f98 R08: ffff926b61b24d00 R09: 0000000080200018
[  247.122048] R10: ffff926b61b24d00 R11: ffff926a8040c000 R12: ffff927bd09a2000
[  247.122048] R13: ffffffff89e31fa0 R14: dead000000000122 R15: dead000000000100
[  247.122048] FS:  00007f01be0a8c40(0000) GS:ffff926fa8e40000(0000)
knlGS:0000000000000000
[  247.122048] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  247.122048] CR2: 0000000000000008 CR3: 00000001145c6003 CR4: 00000000007706e0
[  247.122048] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  247.122048] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  247.122048] PKRU: 55555554
[  247.122048] Call Trace:
[  247.122048]  <TASK>
[  247.122048]  rdt_kill_sb+0x29d/0x350
[  247.122048]  deactivate_locked_super+0x36/0xa0
[  247.122048]  cleanup_mnt+0x131/0x190
[  247.122048]  task_work_run+0x5c/0x90
[  247.122048]  exit_to_user_mode_prepare+0x229/0x230
[  247.122048]  syscall_exit_to_user_mode+0x18/0x40
[  247.122048]  do_syscall_64+0x48/0x90
[  247.122048]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[  247.122048] RIP: 0033:0x7f01be2d735b
```

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215696
Link: https://lore.kernel.org/lkml/CAE4VaGDZr_4wzRn2___eDYRtmdPaGGJdzu_LCSkJYuY9BEO3cw@mail.gmail.com/
Fixes: 393c371408 (kernfs: switch global kernfs_rwsem lock to per-fs lock)
Cc: stable@vger.kernel.org
Reported-by: Jirka Hladky <jhladky@redhat.com>
Tested-by: Jirka Hladky <jhladky@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Link: https://lore.kernel.org/r/20220427172152.3505364-1-minchan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-27 19:32:07 +02:00
..
9p Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
adfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
affs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
afs Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
autofs
befs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
bfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
btrfs for-5.18-rc1-tag 2022-04-05 08:59:37 -07:00
cachefiles Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
ceph Filesystem/VFS changes for 5.18, part two 2022-04-01 13:50:50 -07:00
cifs cifs: update internal module number 2022-04-04 22:40:14 -05:00
coda Folio changes for 5.18 2022-03-22 17:03:12 -07:00
configfs configfs: fix a race in configfs_{,un}register_subsystem() 2022-02-22 18:30:28 +01:00
cramfs
crypto fs: Remove ->readpages address space operation 2022-04-01 13:45:33 -04:00
debugfs debugfs: Document that debugfs_create functions need not be error checked 2022-02-25 11:56:13 +01:00
devpts fsnotify: fix fsnotify hooks in pseudo filesystems 2022-01-24 14:17:02 +01:00
dlm driver core changes for 5.17-rc1 2022-01-12 11:11:34 -08:00
ecryptfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
efivarfs
efs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
erofs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
exfat Description for this pull request: 2022-04-01 14:20:24 -07:00
exportfs
ext2 \n 2022-03-25 17:38:15 -07:00
ext4 ext4: Correct ext4_journalled_dirty_folio() conversion 2022-04-01 14:40:44 -04:00
f2fs f2fs: Get the superblock from the mapping instead of the page 2022-04-01 14:40:44 -04:00
fat Merge branch 'akpm' (patches from Andrew) 2022-03-24 14:14:07 -07:00
freevxfs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
fscache Netfs prep for write helpers 2022-03-31 15:49:36 -07:00
fuse fs: Remove ->readpages address space operation 2022-04-01 13:45:33 -04:00
gfs2 gfs2 fixes 2022-03-31 15:57:50 -07:00
hfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
hfsplus Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
hostfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
hpfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
hugetlbfs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
iomap iomap: Simplify is_partially_uptodate a little 2022-04-01 14:40:43 -04:00
isofs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
jbd2 Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
jffs2 This pull request contains fixes for JFFS2, UBI and UBIFS 2022-03-31 16:09:41 -07:00
jfs A couple bug fixes 2022-03-29 18:17:30 -07:00
kernfs kernfs: fix NULL dereferencing in kernfs_remove 2022-04-27 19:32:07 +02:00
ksmbd six ksmbd server fixes 2022-04-01 14:39:28 -07:00
lockd NFSD: Move svc_serv_ops::svo_function into struct svc_serv 2022-02-28 10:26:40 -05:00
minix Merge branch 'akpm' (patches from Andrew) 2022-03-24 14:14:07 -07:00
netfs netfs: Split some core bits out into their own file 2022-03-18 09:29:05 +00:00
nfs NFS client bugfixes for Linux 5.18 2022-04-08 07:39:17 -10:00
nfs_common
nfsd Folio changes for 5.18 2022-03-22 17:03:12 -07:00
nilfs2 nilfs2: get rid of nilfs_mapping_init() 2022-04-01 11:46:09 -07:00
nls
notify fsnotify: remove redundant parameter judgment 2022-03-14 09:05:25 +01:00
ntfs ntfs: Correct mark_ntfs_record_dirty() folio conversion 2022-04-01 14:40:44 -04:00
ntfs3 Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
ocfs2 ocfs2: fix crash when mount with quota enabled 2022-04-01 11:46:09 -07:00
omfs fs: Convert __set_page_dirty_buffers to block_dirty_folio 2022-03-16 13:37:04 -04:00
openpromfs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
orangefs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
overlayfs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
proc Updates to Tracing: 2022-04-03 12:26:01 -07:00
pstore pstore: Don't use semaphores in always-atomic-context code 2022-03-15 11:08:23 -07:00
qnx4 fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
qnx6 fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
quota quota: make dquot_quota_sync return errors from ->sync_fs 2022-01-30 08:59:47 -08:00
ramfs
reiserfs \n 2022-03-25 17:38:15 -07:00
romfs fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
smbfs_common smb3: fix ksmbd bigendian bug in oplock break, and move its struct to smbfs_common 2022-03-31 09:38:53 -05:00
squashfs Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
sysfs kobject: kobj_type: remove default_attrs 2022-04-05 15:39:19 +02:00
sysv Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
tracefs tracefs: Set the group ownership in apply_options() not parse_options() 2022-02-25 21:05:04 -05:00
ubifs This pull request contains fixes for JFFS2, UBI and UBIFS 2022-03-31 16:09:41 -07:00
udf \n 2022-03-25 17:38:15 -07:00
ufs Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
unicode kbuild: unify cmd_copy and cmd_shipped 2022-02-14 10:37:32 +09:00
vboxsf Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
verity fs: Remove ->readpages address space operation 2022-04-01 13:45:33 -04:00
xfs Bug fixes for 5.18: 2022-04-01 19:30:44 -07:00
zonefs for-5.18/write-streams-2022-03-18 2022-03-26 11:51:46 -07:00
aio.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf_fdpic.c coredump: Snapshot the vmas in do_coredump 2022-03-08 12:55:29 -06:00
binfmt_elf_test.c binfmt_elf: Introduce KUnit test 2022-03-03 20:38:56 -08:00
binfmt_elf.c execve updates for v5.18-rc1 2022-03-21 19:16:02 -07:00
binfmt_flat.c coredump: Don't compile flat_core_dump when coredumps are disabled 2022-03-09 10:37:07 -06:00
binfmt_misc.c Fix regression due to "fs: move binfmt_misc sysctl to its own file" 2022-02-09 09:50:02 -08:00
binfmt_script.c
buffer.c filemap: Remove AOP_FLAG_CONT_EXPAND 2022-04-01 14:40:44 -04:00
char_dev.c
compat_binfmt_elf.c binfmt_elf: Introduce KUnit test 2022-03-03 20:38:56 -08:00
coredump.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
d_path.c
dax.c dax for 5.18 2022-03-24 18:12:09 -07:00
dcache.c mm: dcache: use kmem_cache_alloc_lru() to allocate dentry 2022-03-22 15:57:03 -07:00
direct-io.c block: remove the per-bio/request write hint 2022-03-07 12:45:57 -07:00
drop_caches.c
eventfd.c
eventpoll.c eventpoll: simplify sysctl declaration with register_sysctl() 2022-01-22 08:33:35 +02:00
exec.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
fcntl.c fs: remove fs.f_write_hint 2022-03-08 17:55:03 -07:00
fhandle.c
file_table.c SUNRPC: Ensure we flush any closed sockets before xs_xprt_free() 2022-04-07 16:19:47 -04:00
file.c fs: fix fd table size alignment properly 2022-03-29 23:29:18 -07:00
filesystems.c
fs_context.c vfs: fs_context: fix up param length parsing in legacy_parse_param 2022-01-18 09:23:19 +02:00
fs_parser.c
fs_pin.c
fs_struct.c
fs_types.c
fs-writeback.c Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
fsopen.c
init.c
inode.c fs: introduce alloc_inode_sb() to allocate filesystems specific inode 2022-03-22 15:57:03 -07:00
internal.h Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
io_uring.c io_uring: fix race between timeout flush and removal 2022-04-08 14:50:05 -06:00
io-wq.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
io-wq.h io_uring: defer file assignment 2022-04-07 11:17:28 -06:00
ioctl.c Fixes for 5.18-rc1: 2022-04-01 19:35:56 -07:00
Kconfig Folio changes for 5.18 2022-03-22 17:03:12 -07:00
Kconfig.binfmt execve updates for v5.18-rc1 2022-03-21 19:16:02 -07:00
kernel_read_file.c
libfs.c fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio 2022-03-16 13:37:05 -04:00
locks.c fs: move locking sysctls where they are used 2022-01-22 08:33:36 +02:00
Makefile Fix from Christoph Hellwig merging the CONFIG_UNICODE_UTF8_DATA into the 2022-02-01 11:13:24 -08:00
mbcache.c
mount.h
mpage.c for-5.18/alloc-cleanups-2022-03-25 2022-03-26 11:59:30 -07:00
namei.c \n 2022-01-28 17:51:31 +02:00
namespace.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
no-block.c
nsfs.c
open.c fs: remove fs.f_write_hint 2022-03-08 17:55:03 -07:00
pipe.c fs/pipe.c: local vars have to match types of proper pipe_inode_info fields 2022-03-23 19:00:34 -07:00
pnode.c
pnode.h
posix_acl.c
proc_namespace.c
read_write.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2022-04-01 19:57:03 -07:00
readdir.c
remap_range.c Filesystem folio changes for 5.18 2022-03-22 18:26:56 -07:00
select.c select: Fix indefinitely sleeping task in poll_schedule_timeout() 2022-01-11 09:03:05 -08:00
seq_file.c seq_file: fix NULL pointer arithmetic warning 2022-02-01 11:31:55 -05:00
signalfd.c Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
splice.c mm: Convert remove_mapping() to take a folio 2022-03-21 12:59:01 -04:00
stack.c
stat.c io-uring: Make statx API stable 2022-03-10 09:33:55 -07:00
statfs.c
super.c vfs: make freeze_super abort when sync_filesystem returns error 2022-01-30 08:59:47 -08:00
sync.c vfs: make sync_filesystem return errors from ->sync_fs 2022-01-30 08:59:47 -08:00
sysctls.c fs: move namespace sysctls and declare fs base directory 2022-01-22 08:33:36 +02:00
timerfd.c
userfaultfd.c userfaultfd: provide unmasked address on page-fault 2022-03-22 15:57:08 -07:00
utimes.c
xattr.c