linux/fs
Jens Axboe 7271ef3a93 io_uring: fix recursive completion locking on oveflow flush
syszbot reports a scenario where we recurse on the completion lock
when flushing an overflow:

1 lock held by syz-executor287/6816:
 #0: ffff888093cdb4d8 (&ctx->completion_lock){....}-{2:2}, at: io_cqring_overflow_flush+0xc6/0xab0 fs/io_uring.c:1333

stack backtrace:
CPU: 1 PID: 6816 Comm: syz-executor287 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1f0/0x31e lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:2391 [inline]
 check_deadlock kernel/locking/lockdep.c:2432 [inline]
 validate_chain+0x69a4/0x88a0 kernel/locking/lockdep.c:3202
 __lock_acquire+0x1161/0x2ab0 kernel/locking/lockdep.c:4426
 lock_acquire+0x160/0x730 kernel/locking/lockdep.c:5005
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0x67/0x80 kernel/locking/spinlock.c:167
 spin_lock_irq include/linux/spinlock.h:379 [inline]
 io_queue_linked_timeout fs/io_uring.c:5928 [inline]
 __io_queue_async_work fs/io_uring.c:1192 [inline]
 __io_queue_deferred+0x36a/0x790 fs/io_uring.c:1237
 io_cqring_overflow_flush+0x774/0xab0 fs/io_uring.c:1359
 io_ring_ctx_wait_and_kill+0x2a1/0x570 fs/io_uring.c:7808
 io_uring_release+0x59/0x70 fs/io_uring.c:7829
 __fput+0x34f/0x7b0 fs/file_table.c:281
 task_work_run+0x137/0x1c0 kernel/task_work.c:135
 exit_task_work include/linux/task_work.h:25 [inline]
 do_exit+0x5f3/0x1f20 kernel/exit.c:806
 do_group_exit+0x161/0x2d0 kernel/exit.c:903
 __do_sys_exit_group+0x13/0x20 kernel/exit.c:914
 __se_sys_exit_group+0x10/0x10 kernel/exit.c:912
 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:912
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by passing back the link from __io_queue_async_work(), and
then let the caller handle the queueing of the link. Take care to also
punt the submission reference put to the caller, as we're holding the
completion lock for the __io_queue_defer() case. Hence we need to mark
the io_kiocb appropriately for that case.

Reported-by: syzbot+996f91b6ec3812c48042@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-10 15:19:25 -06:00
..
9p 9p: read only once on O_NONBLOCK 2020-03-27 09:29:56 +00:00
adfs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
affs block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
afs afs: Fix interruption of operations 2020-07-15 15:49:04 -07:00
autofs autofs: switch to kernel_write 2020-07-08 08:27:56 +02:00
befs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
bfs docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
btrfs These are the latest RCU bits for v5.9: 2020-08-03 14:31:33 -07:00
cachefiles cachefiles: switch to kernel_write 2020-07-08 08:27:56 +02:00
ceph ceph: skip checking caps when session reconnecting and releasing reqs 2020-06-01 13:22:53 +02:00
cifs Revert "cifs: Fix the target file was deleted when rename failed." 2020-07-23 15:44:11 -05:00
coda docs: filesystems: convert coda.txt to ReST 2020-05-05 09:22:21 -06:00
configfs A fair amount of stuff this time around, dominated by yet another massive 2020-06-01 15:45:27 -07:00
cramfs docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
crypto fscrypt: don't load ->i_crypt_info before it's known to be valid 2020-07-30 14:21:50 -07:00
debugfs Merge 5.7-rc3 into driver-core-next 2020-04-27 09:34:55 +02:00
devpts
dlm dlm for 5.8 2020-06-05 16:43:16 -07:00
ecryptfs A fair amount of stuff this time around, dominated by yet another massive 2020-06-01 15:45:27 -07:00
efivarfs efi/efivars: Expose RT service availability via efivars abstraction 2020-07-09 10:14:29 +03:00
efs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
erofs erofs: fix partially uninitialized misuse in z_erofs_onlinepage_fixup 2020-06-24 09:47:44 +08:00
exfat exfat: fix name_hash computation on big endian systems 2020-07-21 10:44:19 +09:00
exportfs
ext2 mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
ext4 ext4: add inline encryption support 2020-07-08 10:29:43 -07:00
f2fs f2fs: add inline encryption support 2020-07-08 10:29:43 -07:00
fat fat: improve the readahead for FAT entries 2020-06-04 19:06:25 -07:00
freevxfs
fscache Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-06-03 16:27:18 -07:00
fuse fuse: Fix parameter for FS_IOC_{GET,SET}FLAGS 2020-07-15 14:18:20 +02:00
gfs2 gfs2: Rework read and page fault locking 2020-07-07 23:40:12 +02:00
hfs block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
hfsplus block: remove the error_sector argument to blkdev_issue_flush 2020-05-22 08:45:46 -06:00
hostfs hostfs: Use kasprintf() instead of fixed buffer formatting 2020-03-29 23:23:00 +02:00
hpfs hpfs: fix warning due to superfluous semicolon 2020-06-06 10:08:17 -07:00
hugetlbfs mmap locking API: convert mmap_sem API comments 2020-06-09 09:39:14 -07:00
iomap New code for 5.8: 2020-06-13 12:44:30 -07:00
isofs isofs: remove a stale comment 2020-07-08 16:20:01 -06:00
jbd2 This is the second round of ext4 commits for 5.8 merge window. It 2020-06-15 09:32:10 -07:00
jffs2 jffs2: Replace zero-length array with flexible-array 2020-06-15 23:08:31 -05:00
jfs block: move struct block_device to blk_types.h 2020-06-24 09:16:02 -06:00
kernfs mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
lockd proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
minix
nfs SUNRPC reverting d03727b248 ("NFSv4 fix CLOSE not waiting for direct IO compeletion") 2020-07-17 14:47:38 -04:00
nfs_common
nfsd nfsd4: fix NULL dereference in nfsd/clients display code 2020-07-22 16:47:14 -04:00
nilfs2 nilfs2: fix null pointer dereference at nilfs_segctor_do_construct() 2020-06-10 19:14:17 -07:00
nls treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
notify treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
ntfs block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
ocfs2 ocfs2: fix value of OCFS2_INVALID_SLOT 2020-06-26 00:27:37 -07:00
omfs fs: convert mpage_readpages to mpage_readahead 2020-06-02 10:59:07 -07:00
openpromfs
orangefs orangefs: a conversion and a cleanup... 2020-06-05 16:44:36 -07:00
overlayfs ovl: fix lookup of indexed hardlinks with metacopy 2020-07-16 07:24:47 +02:00
proc for-5.9/block-20200802 2020-08-03 11:57:03 -07:00
pstore Merge branch 'uaccess.__copy_from_user' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-01 16:18:46 -07:00
qnx4
qnx6 fs: convert mpage_readpages to mpage_readahead 2020-06-02 10:59:07 -07:00
quota block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
ramfs fs_parse: fold fs_parameter_desc/fs_parameter_spec 2020-02-07 14:48:37 -05:00
reiserfs block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
romfs treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
squashfs squashfs: fix length field overlap check in metadata reading 2020-07-24 12:42:41 -07:00
sysfs RDMA 5.8 merge window pull request 2020-06-05 14:05:57 -07:00
sysv docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
tracefs
ubifs mm: remove the pgprot argument to __vmalloc 2020-06-02 10:59:11 -07:00
udf for-5.8/block-2020-06-01 2020-06-02 15:29:19 -07:00
ufs
unicode .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
vboxsf vboxsf: don't use the source name in the bdi name 2020-05-07 08:45:47 -06:00
verity fs-verity: use smp_load_acquire() for ->i_verity_info 2020-07-21 16:02:41 -07:00
xfs for-5.9/io_uring-20200802 2020-08-03 13:01:22 -07:00
zonefs zonefs: count pages after truncating the iterator 2020-07-20 17:59:31 +09:00
aio.c aio: Replace zero-length array with flexible-array 2020-06-15 23:08:25 -05:00
anon_inodes.c
attr.c
bad_inode.c fs: move the fiemap definitions out of fs.h 2020-06-03 23:16:55 -04:00
binfmt_aout.c exec: Rename flush_old_exec begin_new_exec 2020-05-07 16:55:47 -05:00
binfmt_elf.c Merge branch 'uaccess.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-10 16:02:54 -07:00
binfmt_elf_fdpic.c Merge branch 'uaccess.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-10 16:02:54 -07:00
binfmt_em86.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
binfmt_flat.c Merge branch 'uaccess.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-10 16:02:54 -07:00
binfmt_misc.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
binfmt_script.c Merge branch 'akpm' (patches from Andrew) 2020-06-04 19:18:29 -07:00
block_dev.c for-5.9/io_uring-20200802 2020-08-03 13:01:22 -07:00
buffer.c for-5.9/block-20200802 2020-08-03 11:57:03 -07:00
char_dev.c vfs: allow unprivileged whiteout creation 2020-05-14 16:44:23 +02:00
compat.c
compat_binfmt_elf.c Split the old READ_IMPLIES_EXEC workaround from executable PT_GNU_STACK 2020-06-05 13:45:21 -07:00
coredump.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
d_path.c
dax.c dax,iomap: Add helper dax_iomap_zero() to zero a range 2020-04-02 19:15:03 -07:00
dcache.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-06-03 16:27:18 -07:00
dcookies.c
direct-io.c block: remove the bd_queue field from struct block_device 2020-07-01 08:08:20 -06:00
drop_caches.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
eventfd.c eventfd: convert to f_op->read_iter() 2020-05-06 22:33:43 -04:00
eventpoll.c epoll: call final ep_events_available() check under the lock 2020-05-14 10:00:35 -07:00
exec.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
fcntl.c fcntl: Distribute switch variables for initialization 2020-03-03 10:55:06 -05:00
fhandle.c
file.c fix multiplication overflow in copy_fdtable() 2020-05-19 18:29:36 -04:00
file_table.c Revert "fs: Do not check if there is a fsnotify watcher on pseudo inodes" 2020-06-29 09:40:55 -07:00
filesystems.c fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() 2020-04-10 15:36:22 -07:00
fs-writeback.c A lot of bug fixes and cleanups for ext4, including: 2020-06-05 16:19:28 -07:00
fs_context.c vfs: don't parse "silent" option 2020-05-14 16:44:25 +02:00
fs_parser.c fs_parse: remove pr_notice() about each validation 2020-04-02 09:35:26 -07:00
fs_pin.c
fs_struct.c
fs_types.c
fsopen.c add prefix to fs_context->log 2020-02-07 14:48:35 -05:00
inode.c AFS Changes 2020-06-05 16:26:36 -07:00
internal.h block: move block-related definitions out of fs.h 2020-06-24 09:16:02 -06:00
io-wq.c io-wq: update hash bits 2020-07-25 09:47:44 -06:00
io-wq.h io_uring/io-wq: move RLIMIT_FSIZE to io-wq 2020-07-24 13:00:44 -06:00
io_uring.c io_uring: fix recursive completion locking on oveflow flush 2020-08-10 15:19:25 -06:00
ioctl.c fs: remove the access_ok() check in ioctl_fiemap 2020-06-03 23:16:55 -04:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Kconfig.binfmt treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
libfs.c block: remove the error_sector argument to blkdev_issue_flush 2020-05-22 08:45:46 -06:00
locks.c File locking fix for v5.9. 2020-08-03 10:46:41 -07:00
Makefile exfat: add Kconfig and Makefile 2020-03-05 21:00:40 -05:00
mbcache.c
mount.h proc/mounts: add cursor 2020-05-14 16:44:24 +02:00
mpage.c fs: convert mpage_readpages to mpage_readahead 2020-06-02 10:59:07 -07:00
namei.c vfs: clean up posix_acl_permission() logic aroudn MAY_NOT_BLOCK 2020-06-08 11:04:19 -07:00
namespace.c fuse: reject options on reconfigure via fsconfig(2) 2020-07-14 14:45:41 +02:00
no-block.c
nsfs.c nsproxy: attach to namespaces via pidfds 2020-05-13 11:41:22 +02:00
open.c Merge branch 'akpm' (patches from Andrew) 2020-06-02 12:21:36 -07:00
pipe.c Notifications over pipes + Keyring notifications 2020-06-13 09:56:21 -07:00
pnode.c propagate_one(): mnt_set_mountpoint() needs mount_lock 2020-04-27 10:37:14 -04:00
pnode.h
posix_acl.c vfs: clean up posix_acl_permission() logic aroudn MAY_NOT_BLOCK 2020-06-08 11:04:19 -07:00
proc_namespace.c Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2020-06-04 13:54:34 -07:00
read_write.c fs: remove __vfs_read 2020-07-08 08:27:57 +02:00
readdir.c readdir.c: get rid of the last __put_user(), drop now-useless access_ok() 2020-05-01 20:29:54 -04:00
select.c pselect6() and friends: take handling the combined 6th/7th args into helper 2020-05-29 19:10:42 -04:00
seq_file.c fs/seq_file.c: seq_read: Update pr_info_ratelimited 2020-06-04 19:06:25 -07:00
signalfd.c
splice.c Notifications over pipes + Keyring notifications 2020-06-13 09:56:21 -07:00
stack.c
stat.c New code for 5.8: 2020-06-02 19:45:12 -07:00
statfs.c
super.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-06-10 16:09:11 -07:00
sync.c overlayfs update for 5.8 2020-06-09 15:40:50 -07:00
timerfd.c
userfaultfd.c userfaultfd: simplify fault handling 2020-08-03 11:25:16 -07:00
utimes.c utimensat: AT_EMPTY_PATH support 2020-05-14 16:44:24 +02:00
xattr.c xattr: fix uninitialized out-param 2020-04-09 15:33:09 -04:00