syzbot


possible deadlock in ocfs2_truncate_file

Status: upstream: reported on 2024/12/01 05:06
Reported-by: syzbot+3597623c9c1c862c69ec@syzkaller.appspotmail.com
First crash: 20d, last: 20d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in ocfs2_truncate_file 6 15d 80d 0/3 upstream: reported on 2024/10/02 11:36
upstream possible deadlock in ocfs2_truncate_file ocfs2 123 3h44m 119d 0/28 upstream: reported on 2024/08/24 04:12

Sample crash report:
ocfs2: Mounting device (7,5) on (node local, slot 0) with writeback data mode.
======================================================
WARNING: possible circular locking dependency detected
6.1.119-syzkaller #0 Not tainted
------------------------------------------------------
syz.5.669/7351 is trying to acquire lock:
ffff0000d99ee650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ffff0000d99ee650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496

but task is already holding lock:
ffff0000e15d22e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x5c/0x88 kernel/locking/rwsem.c:1573
       ocfs2_try_remove_refcount_tree+0xb4/0x2f0 fs/ocfs2/refcounttree.c:932
       ocfs2_xattr_set+0x7b8/0x1478 fs/ocfs2/xattr.c:3673
       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
       removexattr fs/xattr.c:878 [inline]
       path_removexattr+0x1ec/0x2ec fs/xattr.c:892
       __do_sys_removexattr fs/xattr.c:906 [inline]
       __se_sys_removexattr fs/xattr.c:903 [inline]
       __arm64_sys_removexattr+0x60/0x78 fs/xattr.c:903
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x58/0x13c 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_create+0x1a8/0x560 fs/ocfs2/namei.c:672
       lookup_open fs/namei.c:3482 [inline]
       open_last_lookups fs/namei.c:3550 [inline]
       path_openat+0xeac/0x2548 fs/namei.c:3780
       do_filp_open+0x1bc/0x3cc fs/namei.c:3810
       do_sys_openat2+0x128/0x3e0 fs/open.c:1318
       do_sys_open fs/open.c:1334 [inline]
       __do_sys_openat fs/open.c:1350 [inline]
       __se_sys_openat fs/open.c:1345 [inline]
       __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x58/0x13c 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+0x2080/0x2cb8 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+0x2080/0x2cb8 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#3){.+.+}-{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_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
       ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496
       ocfs2_setattr+0x142c/0x1b5c fs/ocfs2/file.c:1212
       notify_change+0xb58/0xe1c fs/attr.c:499
       do_truncate+0x1c0/0x28c fs/open.c:65
       handle_truncate fs/namei.c:3285 [inline]
       do_open fs/namei.c:3630 [inline]
       path_openat+0x1fa0/0x2548 fs/namei.c:3783
       do_filp_open+0x1bc/0x3cc fs/namei.c:3810
       do_sys_openat2+0x128/0x3e0 fs/open.c:1318
       do_sys_open fs/open.c:1334 [inline]
       __do_sys_openat fs/open.c:1350 [inline]
       __se_sys_openat fs/open.c:1345 [inline]
       __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
       do_el0_svc+0x58/0x13c 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#3 --> &oi->ip_xattr_sem --> &ocfs2_file_ip_alloc_sem_key

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_file_ip_alloc_sem_key);
                               lock(&oi->ip_xattr_sem);
                               lock(&ocfs2_file_ip_alloc_sem_key);
  lock(sb_internal#3);

 *** DEADLOCK ***

3 locks held by syz.5.669/7351:
 #0: ffff0000d99ee460 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
 #1: ffff0000e15d2648 (&sb->s_type->i_mutex_key#40){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff0000e15d2648 (&sb->s_type->i_mutex_key#40){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
 #2: ffff0000e15d22e0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_truncate_file+0x38c/0x1618 fs/ocfs2/file.c:467

stack backtrace:
CPU: 0 PID: 7351 Comm: syz.5.669 Not tainted 6.1.119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
 ocfs2_truncate_file+0x640/0x1618 fs/ocfs2/file.c:496
 ocfs2_setattr+0x142c/0x1b5c fs/ocfs2/file.c:1212
 notify_change+0xb58/0xe1c fs/attr.c:499
 do_truncate+0x1c0/0x28c fs/open.c:65
 handle_truncate fs/namei.c:3285 [inline]
 do_open fs/namei.c:3630 [inline]
 path_openat+0x1fa0/0x2548 fs/namei.c:3783
 do_filp_open+0x1bc/0x3cc fs/namei.c:3810
 do_sys_openat2+0x128/0x3e0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c 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

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/01 05:06 linux-6.1.y e4d90d63d385 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_truncate_file
* Struck through repros no longer work on HEAD.