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possible deadlock in ocfs2_truncate_file

Status: upstream: reported C repro on 2024/10/02 11:36
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+505e17155790d5758123@syzkaller.appspotmail.com
First crash: 227d, last: 6d14h
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/03/14 linux-5.15.y (ToT) 0c935c049b5c C [report] possible deadlock in ocfs2_truncate_file
2025/03/14 upstream (ToT) e3a854b577cb C Didn't crash
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in ocfs2_truncate_file ocfs2 603 13d 267d 0/28 upstream: reported on 2024/08/24 04:12
linux-6.1 possible deadlock in ocfs2_truncate_file origin:lts-only C error 13 44d 168d 0/3 upstream: reported C repro on 2024/12/01 05:06
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/03/10 17:19 17m retest repro linux-5.15.y report log

Sample crash report:
ocfs2: Slot 0 on device (7,0) was already allocated to this node!
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.178-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor858/4019 is trying to acquire lock:
ffff0000cb970650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
ffff0000cb970650 (sb_internal#2){.+.+}-{0:0}, at: ocfs2_truncate_file+0x5f8/0x14dc fs/ocfs2/file.c:496

but task is already holding lock:
ffff0000dea8dbe0 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_truncate_file+0x344/0x14dc fs/ocfs2/file.c:467

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_alloc_sem){++++}-{3:3}:
       down_read+0xc0/0x398 kernel/locking/rwsem.c:1498
       ocfs2_read_virt_blocks+0x298/0x960 fs/ocfs2/extent_map.c:976
       ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
       ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
       ocfs2_find_entry+0x3ac/0x2450 fs/ocfs2/dir.c:1080
       ocfs2_rename+0x1c68/0x34f0 fs/ocfs2/namei.c:1568
       vfs_rename+0xac8/0xe04 fs/namei.c:4832
       do_renameat2+0xa00/0x10c0 fs/namei.c:4985
       __do_sys_renameat2 fs/namei.c:5018 [inline]
       __se_sys_renameat2 fs/namei.c:5015 [inline]
       __arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5015
       __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_local_alloc_slide_window fs/ocfs2/localalloc.c:1258 [inline]
       ocfs2_reserve_local_alloc_bits+0x998/0x2474 fs/ocfs2/localalloc.c:668
       ocfs2_reserve_clusters_with_limit+0x194/0xabc fs/ocfs2/suballoc.c:1162
       ocfs2_reserve_clusters+0x3c/0x50 fs/ocfs2/suballoc.c:1223
       ocfs2_mknod+0xe08/0x24f8 fs/ocfs2/namei.c:354
       ocfs2_mkdir+0x184/0x4c8 fs/ocfs2/namei.c:657
       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_local_alloc_slide_window fs/ocfs2/localalloc.c:1258 [inline]
       ocfs2_reserve_local_alloc_bits+0x998/0x2474 fs/ocfs2/localalloc.c:668
       ocfs2_reserve_clusters_with_limit+0x194/0xabc fs/ocfs2/suballoc.c:1162
       ocfs2_reserve_clusters+0x3c/0x50 fs/ocfs2/suballoc.c:1223
       ocfs2_mknod+0xe08/0x24f8 fs/ocfs2/namei.c:354
       ocfs2_mkdir+0x184/0x4c8 fs/ocfs2/namei.c:657
       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:1813 [inline]
       sb_start_intwrite include/linux/fs.h:1930 [inline]
       ocfs2_start_trans+0x2dc/0x804 fs/ocfs2/journal.c:350
       ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
       ocfs2_truncate_file+0x5f8/0x14dc fs/ocfs2/file.c:496
       ocfs2_setattr+0xd78/0x1920 fs/ocfs2/file.c:1215
       notify_change+0xa34/0xcf8 fs/attr.c:505
       do_truncate+0x1c0/0x28c fs/open.c:65
       handle_truncate fs/namei.c:3265 [inline]
       do_open fs/namei.c:3612 [inline]
       path_openat+0x20c4/0x26cc fs/namei.c:3742
       do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
       do_sys_openat2+0x128/0x3e0 fs/open.c:1253
       do_sys_open fs/open.c:1269 [inline]
       __do_sys_openat fs/open.c:1285 [inline]
       __se_sys_openat fs/open.c:1280 [inline]
       __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
       __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 --> jbd2_handle --> &oi->ip_alloc_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_alloc_sem);
                               lock(jbd2_handle);
                               lock(&oi->ip_alloc_sem);
  lock(sb_internal#2);

 *** DEADLOCK ***

3 locks held by syz-executor858/4019:
 #0: ffff0000cb970460 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:377
 #1: ffff0000dea8df48 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #1: ffff0000dea8df48 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
 #2: ffff0000dea8dbe0 (&oi->ip_alloc_sem){++++}-{3:3}, at: ocfs2_truncate_file+0x344/0x14dc fs/ocfs2/file.c:467

stack backtrace:
CPU: 1 PID: 4019 Comm: syz-executor858 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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:1813 [inline]
 sb_start_intwrite include/linux/fs.h:1930 [inline]
 ocfs2_start_trans+0x2dc/0x804 fs/ocfs2/journal.c:350
 ocfs2_orphan_for_truncate fs/ocfs2/file.c:392 [inline]
 ocfs2_truncate_file+0x5f8/0x14dc fs/ocfs2/file.c:496
 ocfs2_setattr+0xd78/0x1920 fs/ocfs2/file.c:1215
 notify_change+0xa34/0xcf8 fs/attr.c:505
 do_truncate+0x1c0/0x28c fs/open.c:65
 handle_truncate fs/namei.c:3265 [inline]
 do_open fs/namei.c:3612 [inline]
 path_openat+0x20c4/0x26cc fs/namei.c:3742
 do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
 do_sys_openat2+0x128/0x3e0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
 __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

Crashes (19):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/24 15:21 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/03/12 22:55 linux-5.15.y c16c81c81336 1a5d9317 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_truncate_file
2025/02/03 12:10 linux-5.15.y c16c81c81336 a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_truncate_file
2025/01/09 11:30 linux-5.15.y 91786f140358 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_truncate_file
2025/01/07 11:18 linux-5.15.y 91786f140358 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in ocfs2_truncate_file
2025/05/11 20:23 linux-5.15.y 3b8db0e4f263 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/04/24 18:49 linux-5.15.y f7347f400572 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/04/24 17:57 linux-5.15.y f7347f400572 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/04/24 03:54 linux-5.15.y f7347f400572 73a168d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/04/02 06:36 linux-5.15.y 0c935c049b5c c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/02/24 14:21 linux-5.15.y c16c81c81336 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/01/20 13:22 linux-5.15.y 4735586da88e f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2025/01/15 15:42 linux-5.15.y 4735586da88e 7315a7cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/12/06 19:37 linux-5.15.y 0a51d2d4527b 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/11/29 03:17 linux-5.15.y 0a51d2d4527b 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/11/27 05:46 linux-5.15.y 0a51d2d4527b 52b38cc1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/10/26 09:14 linux-5.15.y 74cdd62cb470 65e8686b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/10/25 00:01 linux-5.15.y 74cdd62cb470 c79b8ca5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
2024/10/02 11:35 linux-5.15.y 3a5928702e71 02f9582a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 possible deadlock in ocfs2_truncate_file
* Struck through repros no longer work on HEAD.