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possible deadlock in ocfs2_setattr

Status: upstream: reported C repro on 2024/09/21 07:18
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+50d7961da48e2cadc59a@syzkaller.appspotmail.com
First crash: 7d07h, last: 21h47m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2024/09/21 linux-5.15.y (ToT) 3a5928702e71 C [report] possible deadlock in ocfs2_setattr
2024/09/21 upstream (ToT) 1868f9d0260e C Didn't crash
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in ocfs2_setattr ocfs2 C 412 2h29m 38d 0/28 upstream: reported C repro on 2024/08/21 07:40
linux-6.1 possible deadlock in ocfs2_setattr 1 5d14h 5d14h 0/3 upstream: reported on 2024/09/22 23:55

Sample crash report:
=======================================================
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.167-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor221/4017 is trying to acquire lock:
ffff0000caf7e650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_setattr+0x94c/0x191c fs/ocfs2/file.c:1263

but task is already holding lock:
ffff0000ddad5be0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0x940/0x191c fs/ocfs2/file.c:1262

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+0xbc/0x12c kernel/locking/rwsem.c:1551
       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:947 [inline]
       posix_acl_xattr_set+0x2cc/0x378 fs/posix_acl.c:966
       __vfs_removexattr+0x370/0x38c fs/xattr.c:470
       __vfs_removexattr_locked+0x1d8/0x380 fs/xattr.c:505
       vfs_removexattr+0xe0/0x23c fs/xattr.c:527
       ovl_workdir_create+0x360/0x624 fs/overlayfs/super.c:818
       ovl_make_workdir fs/overlayfs/super.c:1374 [inline]
       ovl_get_workdir+0x344/0x1110 fs/overlayfs/super.c:1524
       ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2080
       mount_nodev+0x68/0x104 fs/super.c:1444
       ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2171
       legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
       vfs_get_tree+0x90/0x274 fs/super.c:1528
       do_new_mount+0x278/0x8fc fs/namespace.c:3005
       path_mount+0x594/0x101c fs/namespace.c:3335
       do_mount fs/namespace.c:3348 [inline]
       __do_sys_mount fs/namespace.c:3556 [inline]
       __se_sys_mount fs/namespace.c:3533 [inline]
       __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3533
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #3 (&oi->ip_xattr_sem){++++}-{3:3}:
       down_read+0xc0/0x398 kernel/locking/rwsem.c:1498
       ocfs2_init_acl+0x2d0/0x778 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x1558/0x24f8 fs/ocfs2/namei.c:408
       ocfs2_mkdir+0x184/0x4c8 fs/ocfs2/namei.c:655
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4065
       do_mkdirat+0x20c/0x610 fs/namei.c:4090
       __do_sys_mkdirat fs/namei.c:4105 [inline]
       __se_sys_mkdirat fs/namei.c:4103 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #2 (jbd2_handle){.+.+}-{0:0}:
       start_this_handle+0xfc0/0x12a4 fs/jbd2/transaction.c:464
       jbd2__journal_start+0x29c/0x7b4 fs/jbd2/transaction.c:521
       jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:560
       ocfs2_start_trans+0x468/0x804 fs/ocfs2/journal.c:354
       ocfs2_mknod+0xe68/0x24f8 fs/ocfs2/namei.c:359
       ocfs2_mkdir+0x184/0x4c8 fs/ocfs2/namei.c:655
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4065
       do_mkdirat+0x20c/0x610 fs/namei.c:4090
       __do_sys_mkdirat fs/namei.c:4105 [inline]
       __se_sys_mkdirat fs/namei.c:4103 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #1 (&journal->j_trans_barrier){.+.+}-{3:3}:
       down_read+0xc0/0x398 kernel/locking/rwsem.c:1498
       ocfs2_start_trans+0x45c/0x804 fs/ocfs2/journal.c:352
       ocfs2_mknod+0xe68/0x24f8 fs/ocfs2/namei.c:359
       ocfs2_mkdir+0x184/0x4c8 fs/ocfs2/namei.c:655
       vfs_mkdir+0x334/0x4e4 fs/namei.c:4065
       do_mkdirat+0x20c/0x610 fs/namei.c:4090
       __do_sys_mkdirat fs/namei.c:4105 [inline]
       __se_sys_mkdirat fs/namei.c:4103 [inline]
       __arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4103
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

-> #0 (sb_internal#2){.+.+}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
       lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1811 [inline]
       sb_start_intwrite include/linux/fs.h:1928 [inline]
       ocfs2_start_trans+0x2dc/0x804 fs/ocfs2/journal.c:350
       ocfs2_setattr+0x94c/0x191c fs/ocfs2/file.c:1263
       notify_change+0xa34/0xcf8 fs/attr.c:505
       ovl_workdir_create+0x498/0x624 fs/overlayfs/super.c:830
       ovl_make_workdir fs/overlayfs/super.c:1374 [inline]
       ovl_get_workdir+0x344/0x1110 fs/overlayfs/super.c:1524
       ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2080
       mount_nodev+0x68/0x104 fs/super.c:1444
       ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2171
       legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
       vfs_get_tree+0x90/0x274 fs/super.c:1528
       do_new_mount+0x278/0x8fc fs/namespace.c:3005
       path_mount+0x594/0x101c fs/namespace.c:3335
       do_mount fs/namespace.c:3348 [inline]
       __do_sys_mount fs/namespace.c:3556 [inline]
       __se_sys_mount fs/namespace.c:3533 [inline]
       __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3533
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
       el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
       el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
       el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

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-executor221/4017:
 #0: ffff0000caf720e0 (&type->s_umount_key#41/1){+.+.}-{3:3}, at: alloc_super+0x1b8/0x844 fs/super.c:229
 #1: ffff0000caf7e460 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:377
 #2: ffff0000ddad5108 (&sb->s_type->i_mutex_key#17/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
 #2: ffff0000ddad5108 (&sb->s_type->i_mutex_key#17/1){+.+.}-{3:3}, at: ovl_workdir_create+0x130/0x624 fs/overlayfs/super.c:768
 #3: ffff0000ddad5f48 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #3: ffff0000ddad5f48 (&sb->s_type->i_mutex_key#19){+.+.}-{3:3}, at: ovl_workdir_create+0x46c/0x624 fs/overlayfs/super.c:829
 #4: ffff0000ddad5be0 (&oi->ip_alloc_sem){+.+.}-{3:3}, at: ocfs2_setattr+0x940/0x191c fs/ocfs2/file.c:1262

stack backtrace:
CPU: 1 PID: 4017 Comm: syz-executor221 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call trace:
 dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __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:2011
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012
 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623
 percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
 __sb_start_write include/linux/fs.h:1811 [inline]
 sb_start_intwrite include/linux/fs.h:1928 [inline]
 ocfs2_start_trans+0x2dc/0x804 fs/ocfs2/journal.c:350
 ocfs2_setattr+0x94c/0x191c fs/ocfs2/file.c:1263
 notify_change+0xa34/0xcf8 fs/attr.c:505
 ovl_workdir_create+0x498/0x624 fs/overlayfs/super.c:830
 ovl_make_workdir fs/overlayfs/super.c:1374 [inline]
 ovl_get_workdir+0x344/0x1110 fs/overlayfs/super.c:1524
 ovl_fill_super+0x15b4/0x2254 fs/overlayfs/super.c:2080
 mount_nodev+0x68/0x104 fs/super.c:1444
 ovl_mount+0x3c/0x50 fs/overlayfs/super.c:2171
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:611
 vfs_get_tree+0x90/0x274 fs/super.c:1528
 do_new_mount+0x278/0x8fc fs/namespace.c:3005
 path_mount+0x594/0x101c fs/namespace.c:3335
 do_mount fs/namespace.c:3348 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount fs/namespace.c:3533 [inline]
 __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3533
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
overlayfs: upper fs does not support tmpfile.
overlayfs: upper fs does not support RENAME_WHITEOUT.
overlayfs: upper fs missing required features.

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/21 10:42 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/21 09:48 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/21 08:59 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/21 08:08 linux-5.15.y 3a5928702e71 6f888b75 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/27 16:31 linux-5.15.y 3a5928702e71 9314348a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/26 11:03 linux-5.15.y 3a5928702e71 0d19f247 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
2024/09/21 07:17 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_setattr
* Struck through repros no longer work on HEAD.