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possible deadlock in ocfs2_setattr

Status: upstream: reported on 2024/09/22 23:55
Reported-by: syzbot+b7d1ddca885cd6bdb6ce@syzkaller.appspotmail.com
First crash: 5d12h, last: 5d12h
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in ocfs2_setattr ocfs2 C 412 25m 38d 0/28 upstream: reported C repro on 2024/08/21 07:40
linux-5.15 possible deadlock in ocfs2_setattr origin:lts-only C 7 19h43m 7d04h 0/3 upstream: reported C repro on 2024/09/21 07:18

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.1.111-syzkaller #0 Not tainted
------------------------------------------------------
syz.4.42/4545 is trying to acquire lock:
ffff0000f776a650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_setattr+0xb14/0x1b3c fs/ocfs2/file.c:1260

but task is already holding lock:
ffff0000e36822e0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0xb08/0x1b3c fs/ocfs2/file.c:1259

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&oi->ip_alloc_sem){+.+.}-{3:3}:
       down_write+0x5c/0x88 kernel/locking/rwsem.c:1573
       ocfs2_try_remove_refcount_tree+0xb4/0x2f0 fs/ocfs2/refcounttree.c:931
       ocfs2_xattr_set+0x7b8/0x1478 fs/ocfs2/xattr.c:3665
       ocfs2_set_acl+0x410/0x4b4 fs/ocfs2/acl.c:254
       ocfs2_iop_set_acl+0x214/0x358 fs/ocfs2/acl.c:285
       set_posix_acl fs/posix_acl.c:1160 [inline]
       posix_acl_xattr_set+0x2f8/0x398 fs/posix_acl.c:1189
       __vfs_removexattr+0x370/0x38c fs/xattr.c:479
       __vfs_removexattr_locked+0x1d8/0x380 fs/xattr.c:514
       vfs_removexattr+0xe0/0x23c fs/xattr.c:536
       ovl_do_removexattr fs/overlayfs/overlayfs.h:270 [inline]
       ovl_workdir_create+0x400/0x7c8 fs/overlayfs/super.c:821
       ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
       ovl_get_workdir+0x354/0x13d4 fs/overlayfs/super.c:1539
       ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2095
       mount_nodev+0x68/0x104 fs/super.c:1489
       ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2186
       legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
       vfs_get_tree+0x90/0x274 fs/super.c:1573
       do_new_mount+0x278/0x8fc fs/namespace.c:3051
       path_mount+0x590/0xe5c fs/namespace.c:3381
       do_mount fs/namespace.c:3394 [inline]
       __do_sys_mount fs/namespace.c:3602 [inline]
       __se_sys_mount fs/namespace.c:3579 [inline]
       __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3579
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #3 (&oi->ip_xattr_sem){++++}-{3:3}:
       down_read+0x64/0x308 kernel/locking/rwsem.c:1520
       ocfs2_init_acl+0x2c8/0x764 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x1574/0x2560 fs/ocfs2/namei.c:408
       ocfs2_mkdir+0x1a8/0x560 fs/ocfs2/namei.c:655
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4108
       do_mkdirat+0x220/0x510 fs/namei.c:4133
       __do_sys_mkdirat fs/namei.c:4148 [inline]
       __se_sys_mkdirat fs/namei.c:4146 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4146
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #2 (jbd2_handle){++++}-{0:0}:
       start_this_handle+0x1140/0x13ac fs/jbd2/transaction.c:463
       jbd2__journal_start+0x298/0x544 fs/jbd2/transaction.c:520
       jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559
       ocfs2_start_trans+0x3e8/0x73c fs/ocfs2/journal.c:354
       ocfs2_shutdown_local_alloc+0x1d8/0x8d8 fs/ocfs2/localalloc.c:416
       ocfs2_dismount_volume+0x1fc/0x99c fs/ocfs2/super.c:1879
       ocfs2_put_super+0x110/0x3e8 fs/ocfs2/super.c:1609
       generic_shutdown_super+0x130/0x328 fs/super.c:501
       kill_block_super+0x70/0xdc fs/super.c:1470
       deactivate_locked_super+0xac/0x124 fs/super.c:332
       deactivate_super+0xf0/0x110 fs/super.c:363
       cleanup_mnt+0x394/0x41c fs/namespace.c:1186
       __cleanup_mnt+0x20/0x30 fs/namespace.c:1193
       task_work_run+0x240/0x2f0 kernel/task_work.c:203
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       do_notify_resume+0x2148/0x3474 arch/arm64/kernel/signal.c:1132
       prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
       exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
       el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
       down_read+0x64/0x308 kernel/locking/rwsem.c:1520
       ocfs2_start_trans+0x3dc/0x73c fs/ocfs2/journal.c:352
       ocfs2_shutdown_local_alloc+0x1d8/0x8d8 fs/ocfs2/localalloc.c:416
       ocfs2_dismount_volume+0x1fc/0x99c fs/ocfs2/super.c:1879
       ocfs2_put_super+0x110/0x3e8 fs/ocfs2/super.c:1609
       generic_shutdown_super+0x130/0x328 fs/super.c:501
       kill_block_super+0x70/0xdc fs/super.c:1470
       deactivate_locked_super+0xac/0x124 fs/super.c:332
       deactivate_super+0xf0/0x110 fs/super.c:363
       cleanup_mnt+0x394/0x41c fs/namespace.c:1186
       __cleanup_mnt+0x20/0x30 fs/namespace.c:1193
       task_work_run+0x240/0x2f0 kernel/task_work.c:203
       resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
       do_notify_resume+0x2148/0x3474 arch/arm64/kernel/signal.c:1132
       prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
       exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
       el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

-> #0 (sb_internal#2){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3090 [inline]
       check_prevs_add kernel/locking/lockdep.c:3209 [inline]
       validate_chain kernel/locking/lockdep.c:3825 [inline]
       __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
       lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1891 [inline]
       sb_start_intwrite include/linux/fs.h:2013 [inline]
       ocfs2_start_trans+0x260/0x73c fs/ocfs2/journal.c:350
       ocfs2_setattr+0xb14/0x1b3c fs/ocfs2/file.c:1260
       notify_change+0xb58/0xe1c fs/attr.c:499
       ovl_do_notify_change fs/overlayfs/overlayfs.h:142 [inline]
       ovl_workdir_create+0x5d0/0x7c8 fs/overlayfs/super.c:833
       ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
       ovl_get_workdir+0x354/0x13d4 fs/overlayfs/super.c:1539
       ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2095
       mount_nodev+0x68/0x104 fs/super.c:1489
       ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2186
       legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
       vfs_get_tree+0x90/0x274 fs/super.c:1573
       do_new_mount+0x278/0x8fc fs/namespace.c:3051
       path_mount+0x590/0xe5c fs/namespace.c:3381
       do_mount fs/namespace.c:3394 [inline]
       __do_sys_mount fs/namespace.c:3602 [inline]
       __se_sys_mount fs/namespace.c:3579 [inline]
       __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3579
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

other info that might help us debug this:

Chain exists of:
  sb_internal#2 --> &oi->ip_xattr_sem --> &oi->ip_alloc_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_alloc_sem);
                               lock(&oi->ip_xattr_sem);
                               lock(&oi->ip_alloc_sem);
  lock(sb_internal#2);

 *** DEADLOCK ***

5 locks held by syz.4.42/4545:
 #0: ffff0000f3cf00e0 (&type->s_umount_key#48/1){+.+.}-{3:3}, at: alloc_super+0x1b4/0x824 fs/super.c:228
 #1: ffff0000f776a460 (sb_writers#19){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #2: ffff0000e3681808 (&sb->s_type->i_mutex_key#25/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #2: ffff0000e3681808 (&sb->s_type->i_mutex_key#25/1){+.+.}-{3:3}, at: ovl_workdir_create+0x13c/0x7c8 fs/overlayfs/super.c:771
 #3: ffff0000e3682648 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #3: ffff0000e3682648 (&sb->s_type->i_mutex_key#25){+.+.}-{3:3}, at: ovl_workdir_create+0x564/0x7c8 fs/overlayfs/super.c:832
 #4: ffff0000e36822e0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0xb08/0x1b3c fs/ocfs2/file.c:1259

stack backtrace:
CPU: 0 PID: 4545 Comm: syz.4.42 Not tainted 6.1.111-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2048
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3090 [inline]
 check_prevs_add kernel/locking/lockdep.c:3209 [inline]
 validate_chain kernel/locking/lockdep.c:3825 [inline]
 __lock_acquire+0x3338/0x7680 kernel/locking/lockdep.c:5049
 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5662
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1891 [inline]
 sb_start_intwrite include/linux/fs.h:2013 [inline]
 ocfs2_start_trans+0x260/0x73c fs/ocfs2/journal.c:350
 ocfs2_setattr+0xb14/0x1b3c fs/ocfs2/file.c:1260
 notify_change+0xb58/0xe1c fs/attr.c:499
 ovl_do_notify_change fs/overlayfs/overlayfs.h:142 [inline]
 ovl_workdir_create+0x5d0/0x7c8 fs/overlayfs/super.c:833
 ovl_make_workdir fs/overlayfs/super.c:1389 [inline]
 ovl_get_workdir+0x354/0x13d4 fs/overlayfs/super.c:1539
 ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2095
 mount_nodev+0x68/0x104 fs/super.c:1489
 ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2186
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x278/0x8fc fs/namespace.c:3051
 path_mount+0x590/0xe5c fs/namespace.c:3381
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount fs/namespace.c:3579 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3579
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
overlayfs: upper fs does not support tmpfile.
overlayfs: upper fs does not support RENAME_WHITEOUT.
overlayfs: upper fs missing required features.

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/22 23:55 linux-6.1.y e526b12bf916 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_setattr
* Struck through repros no longer work on HEAD.