TencentOS-kernel/fs
Lior Ribak 7677bc43ad binfmt_misc: fix possible deadlock in bm_register_write
commit e7850f4d844e0acfac7e570af611d89deade3146 upstream.

There is a deadlock in bm_register_write:

First, in the begining of the function, a lock is taken on the binfmt_misc
root inode with inode_lock(d_inode(root)).

Then, if the user used the MISC_FMT_OPEN_FILE flag, the function will call
open_exec on the user-provided interpreter.

open_exec will call a path lookup, and if the path lookup process includes
the root of binfmt_misc, it will try to take a shared lock on its inode
again, but it is already locked, and the code will get stuck in a deadlock

To reproduce the bug:
$ echo ":iiiii:E::ii::/proc/sys/fs/binfmt_misc/bla:F" > /proc/sys/fs/binfmt_misc/register

backtrace of where the lock occurs (#5):
0  schedule () at ./arch/x86/include/asm/current.h:15
1  0xffffffff81b51237 in rwsem_down_read_slowpath (sem=0xffff888003b202e0, count=<optimized out>, state=state@entry=2) at kernel/locking/rwsem.c:992
2  0xffffffff81b5150a in __down_read_common (state=2, sem=<optimized out>) at kernel/locking/rwsem.c:1213
3  __down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1222
4  down_read (sem=<optimized out>) at kernel/locking/rwsem.c:1355
5  0xffffffff811ee22a in inode_lock_shared (inode=<optimized out>) at ./include/linux/fs.h:783
6  open_last_lookups (op=0xffffc9000022fe34, file=0xffff888004098600, nd=0xffffc9000022fd10) at fs/namei.c:3177
7  path_openat (nd=nd@entry=0xffffc9000022fd10, op=op@entry=0xffffc9000022fe34, flags=flags@entry=65) at fs/namei.c:3366
8  0xffffffff811efe1c in do_filp_open (dfd=<optimized out>, pathname=pathname@entry=0xffff8880031b9000, op=op@entry=0xffffc9000022fe34) at fs/namei.c:3396
9  0xffffffff811e493f in do_open_execat (fd=fd@entry=-100, name=name@entry=0xffff8880031b9000, flags=<optimized out>, flags@entry=0) at fs/exec.c:913
10 0xffffffff811e4a92 in open_exec (name=<optimized out>) at fs/exec.c:948
11 0xffffffff8124aa84 in bm_register_write (file=<optimized out>, buffer=<optimized out>, count=19, ppos=<optimized out>) at fs/binfmt_misc.c:682
12 0xffffffff811decd2 in vfs_write (file=file@entry=0xffff888004098500, buf=buf@entry=0xa758d0 ":iiiii:E::ii::i:CF
", count=count@entry=19, pos=pos@entry=0xffffc9000022ff10) at fs/read_write.c:603
13 0xffffffff811defda in ksys_write (fd=<optimized out>, buf=0xa758d0 ":iiiii:E::ii::i:CF
", count=19) at fs/read_write.c:658
14 0xffffffff81b49813 in do_syscall_64 (nr=<optimized out>, regs=0xffffc9000022ff58) at arch/x86/entry/common.c:46
15 0xffffffff81c0007c in entry_SYSCALL_64 () at arch/x86/entry/entry_64.S:120

To solve the issue, the open_exec call is moved to before the write
lock is taken by bm_register_write

Link: https://lkml.kernel.org/r/20210228224414.95962-1-liorribak@gmail.com
Fixes: 948b701a607f1 ("binfmt_misc: add persistent opened binary handler for containers")
Signed-off-by: Lior Ribak <liorribak@gmail.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:53:12 +08:00
..
9p 9P: Cast to loff_t before multiplying 2021-03-16 16:40:11 +08:00
adfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
affs fs/affs: release old buffer head on error path 2021-04-12 12:52:38 +08:00
afs rxrpc: Fix deadlock around release of dst cached on udp tunnel 2021-04-12 12:51:53 +08:00
autofs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
befs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
bfs bfs: don't use WARNING: string when it's just info. 2021-03-16 16:43:53 +08:00
btrfs btrfs: fix warning when creating a directory with smack enabled 2021-04-12 12:52:51 +08:00
cachefiles cachefiles: Handle readpage error correctly 2021-03-16 16:40:14 +08:00
ceph ceph: fix race in concurrent __ceph_remove_cap invocations 2021-03-16 16:43:35 +08:00
cifs cifs: return proper error code in statfs(2) 2021-04-12 12:52:58 +08:00
coda Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
configfs configfs: fix a use-after-free in __configfs_open_file 2021-04-12 12:53:11 +08:00
cramfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
crypto fscrypt: remove kernel-internal constants from UAPI header 2021-03-16 16:43:49 +08:00
debugfs debugfs: do not attempt to create a new file before the filesystem is initalized 2021-04-12 12:52:10 +08:00
devpts Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
dlm fs: dlm: fix configfs memory leak 2021-03-16 16:39:15 +08:00
ecryptfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
efivarfs efivarfs: revert "fix memory leak in efivarfs_create()" 2021-03-16 16:41:45 +08:00
efs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
erofs erofs: fix shift-out-of-bounds of blkszbits 2021-04-12 12:52:44 +08:00
exportfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ext2 ext2: don't update mtime on COW faults 2021-03-16 16:35:36 +08:00
ext4 ext4: fix potential htree index checksum corruption 2021-04-12 12:52:30 +08:00
f2fs f2fs: fix to set/clear I_LINKABLE under i_lock 2021-04-12 12:52:48 +08:00
fat fat: don't allow to mount if the FAT length == 0 2021-03-16 16:29:12 +08:00
freevxfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fscache Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fuse fuse: fix bad inode 2021-04-12 12:51:05 +08:00
gfs2 gfs2: Recursive gfs2_quota_hold in gfs2_iomap_end 2021-04-12 12:52:40 +08:00
hfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
hfsplus hfsplus: fix crash and filesystem corruption when deleting files 2021-03-16 16:26:16 +08:00
hostfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
hpfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
hugetlbfs mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page 2021-04-12 12:51:56 +08:00
iomap iomap: fix WARN_ON_ONCE() from unprivileged users 2021-03-16 16:39:20 +08:00
isofs isofs: release buffer head before return 2021-04-12 12:52:25 +08:00
jbd2 jbd2: fix up sparse warnings in checkpoint code 2021-03-16 16:40:54 +08:00
jffs2 jffs2: fix use after free in jffs2_sum_write_data() 2021-04-12 12:52:22 +08:00
jfs JFS: more checks for invalid superblock 2021-04-12 12:52:43 +08:00
kernfs kernfs: do not call fsnotify() with name without a parent 2021-03-16 16:33:35 +08:00
lockd lockd: don't use interval-based rebinding over TCP 2021-03-16 16:42:59 +08:00
minix fs/minix: remove expected error message in block_to_path() 2021-03-16 16:34:21 +08:00
nfs NFSv4.2: fix return value of _nfs4_get_security_label() 2021-04-12 12:53:11 +08:00
nfs_common nfs_common: need lock during iterate through the list 2021-03-16 16:43:09 +08:00
nfsd nfsd: register pernet ops last, unregister first 2021-04-12 12:52:28 +08:00
nilfs2 nilfs2: fix null pointer dereference at nilfs_segctor_do_construct() 2021-03-16 16:29:04 +08:00
nls Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
notify fanotify: fix ignore mask logic for events on child and on dir 2021-03-16 16:28:58 +08:00
ntfs ntfs: check for valid standard information attribute 2021-04-12 12:52:08 +08:00
ocfs2 ocfs2: fix a use after free on error 2021-04-12 12:52:31 +08:00
omfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
openpromfs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
orangefs orangefs: get rid of knob code... 2021-03-16 16:34:10 +08:00
overlayfs ovl: expand warning in ovl_d_real() 2021-04-12 12:52:06 +08:00
proc proc: fix lookup in /proc/net subdirectories after setns(2) 2021-04-12 12:51:06 +08:00
pstore pstore: Fix typo in compression option name 2021-04-12 12:52:36 +08:00
qnx4 Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
qnx6 Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
quota quota: Fix memory leak when handling corrupted quota file 2021-04-12 12:52:22 +08:00
ramfs ramfs: fix nommu mmap with gaps in the page cache 2021-03-16 16:38:58 +08:00
reiserfs reiserfs: add check for an invalid ih_entry_count 2021-03-16 16:43:52 +08:00
romfs romfs: fix uninitialized memory leak in romfs_dev_read() 2021-03-16 16:34:28 +08:00
squashfs squashfs: add more sanity checks in xattr id lookup 2021-04-12 12:52:00 +08:00
sysfs sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output 2021-04-12 12:52:49 +08:00
sysv Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
tracefs Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
ubifs ubifs: Fix error return code in alloc_wbufs() 2021-04-12 12:52:22 +08:00
udf udf: fix silent AED tagLocation corruption 2021-04-12 12:53:02 +08:00
ufs fs/ufs: avoid potential u32 multiplication overflow 2021-03-16 16:34:21 +08:00
unicode Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
verity Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
xfs xfs: Fix assert failure in xfs_setattr_size() 2021-04-12 12:52:44 +08:00
Kconfig Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Kconfig.binfmt Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
Makefile Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
aio.c aio: fix async fsync creds 2021-03-16 16:28:58 +08:00
anon_inodes.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
attr.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
bad_inode.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
binfmt_aout.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
binfmt_elf.c fs/binfmt_elf.c: allocate initialized memory in fill_thread_core_info() 2021-03-16 16:28:37 +08:00
binfmt_elf_fdpic.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
binfmt_em86.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
binfmt_flat.c binfmt_flat: revert "binfmt_flat: don't offset the data start" 2021-03-16 16:34:43 +08:00
binfmt_misc.c binfmt_misc: fix possible deadlock in bm_register_write 2021-04-12 12:53:12 +08:00
binfmt_script.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
block_dev.c bdev: Reduce time holding bd_mutex in sync in blkdev_close() 2021-03-16 16:37:13 +08:00
buffer.c fs: Don't invalidate page buffers in block_write_full_page() 2021-03-16 16:39:56 +08:00
char_dev.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
compat.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
compat_binfmt_elf.c BACKPORT: Split the old READ_IMPLIES_EXEC workaround from executable 2021-03-16 16:43:59 +08:00
compat_ioctl.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
coredump.c coredump: fix core_pattern parse error 2021-03-16 16:42:04 +08:00
d_path.c fs: fix NULL dereference due to data race in prepend_path() 2021-03-16 16:38:47 +08:00
dax.c mm: provide a saner PTE walking API for modules 2021-04-12 12:52:09 +08:00
dcache.c fix dget_parent() fastpath race 2021-03-16 16:36:39 +08:00
dcookies.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
direct-io.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
drop_caches.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
eventfd.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
eventpoll.c ep_create_wakeup_source(): dentry name can change under you... 2021-03-16 16:37:52 +08:00
exec.c exec: Transform exec_update_mutex into a rw_semaphore 2021-04-12 12:51:05 +08:00
fcntl.c fcntl: Fix potential deadlock in send_sig{io, urg}() 2021-03-16 16:43:54 +08:00
fhandle.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
file.c fix multiplication overflow in copy_fdtable() 2021-03-16 16:28:07 +08:00
file_table.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
filesystems.c fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() 2021-03-16 16:26:14 +08:00
fs-writeback.c fs: fix lazytime expiration handling in __writeback_single_inode() 2021-04-12 12:51:42 +08:00
fs_context.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fs_parser.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fs_pin.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fs_struct.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fs_types.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
fsopen.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
inode.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
internal.h Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
io_uring.c io_uring: Fix current->fs handling in io_sq_wq_submit_work() 2021-04-12 12:51:41 +08:00
ioctl.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
libfs.c libfs: fix error cast of negative value in simple_attr_write() 2021-03-16 16:41:24 +08:00
locks.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
mbcache.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
mount.h Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
mpage.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
namei.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
namespace.c fs/namespace.c: WARN if mnt_count has become negative 2021-03-16 16:43:56 +08:00
no-block.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
nsfs.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
open.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
pipe.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
pnode.c propagate_one(): mnt_set_mountpoint() needs mount_lock 2021-03-16 16:27:06 +08:00
pnode.h mount: fix mounting of detached mounts onto targets that reside on shared mounts 2021-04-12 12:52:58 +08:00
posix_acl.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
proc_namespace.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
read_write.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
readdir.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
select.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
seq_file.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
signalfd.c fs/signalfd.c: fix inconsistent return codes for signalfd4 2021-03-16 16:34:34 +08:00
splice.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
stack.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
stat.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
statfs.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
super.c vfs: remove lockdep bogosity in __sb_start_write 2021-03-16 16:41:11 +08:00
sync.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
timerfd.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
userfaultfd.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
utimes.c Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces. 2021-03-16 11:01:34 +08:00
xattr.c xattr: break delegations in {set,remove}xattr 2021-03-16 16:33:08 +08:00