syzbot

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.5.2131/13152 is trying to acquire lock:
ffff8880568bc990 (jbd2_handle){++++}-{0:0}, at: wait_transaction_locked+0x19f/0x270 fs/jbd2/transaction.c:178

but task is already holding lock:
ffff88805f0dd0e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x3a6/0x6f0 fs/ocfs2/journal.c:374

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (&journal->j_trans_barrier){.+.+}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_start_trans+0x3a6/0x6f0 fs/ocfs2/journal.c:374
       ocfs2_modify_bh+0xe0/0x4c0 fs/ocfs2/quota_local.c:101
       ocfs2_local_read_info+0x13c8/0x1750 fs/ocfs2/quota_local.c:764
       dquot_load_quota_sb+0x756/0xac0 fs/quota/dquot.c:2463
       dquot_load_quota_inode+0x2d8/0x5d0 fs/quota/dquot.c:2500
       ocfs2_enable_quotas+0x1c5/0x490 fs/ocfs2/super.c:927
       ocfs2_fill_super+0x3cd2/0x50f0 fs/ocfs2/super.c:1140
       mount_bdev+0x287/0x3c0 fs/super.c:1400
       legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
       vfs_get_tree+0x88/0x270 fs/super.c:1530
       do_new_mount+0x24a/0xa40 fs/namespace.c:3034
       do_mount fs/namespace.c:3377 [inline]
       __do_sys_mount fs/namespace.c:3585 [inline]
       __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #4 (sb_internal#3){.+.+}-{0:0}:
       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+0x2a7/0x6f0 fs/ocfs2/journal.c:372
       ocfs2_acquire_dquot+0x688/0xb10 fs/ocfs2/quota_global.c:848
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8ab/0x2510 fs/ocfs2/namei.c:310
       ocfs2_create+0x192/0x420 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3470 [inline]
       open_last_lookups fs/namei.c:3540 [inline]
       path_openat+0x11db/0x2fa0 fs/namei.c:3747
       do_filp_open+0x1e2/0x410 fs/namei.c:3777
       do_sys_openat2+0x150/0x4b0 fs/open.c:1255
       do_sys_open fs/open.c:1271 [inline]
       __do_sys_openat fs/open.c:1287 [inline]
       __se_sys_openat fs/open.c:1282 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1282
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #3 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_create_local_dquot+0x199/0x1850 fs/ocfs2/quota_local.c:1224
       ocfs2_acquire_dquot+0x7ed/0xb10 fs/ocfs2/quota_global.c:871
       dqget+0x778/0xeb0 fs/quota/dquot.c:988
       __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517
       ocfs2_get_init_inode+0x144/0x1b0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x8ab/0x2510 fs/ocfs2/namei.c:310
       ocfs2_create+0x192/0x420 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3470 [inline]
       open_last_lookups fs/namei.c:3540 [inline]
       path_openat+0x11db/0x2fa0 fs/namei.c:3747
       do_filp_open+0x1e2/0x410 fs/namei.c:3777
       do_sys_openat2+0x150/0x4b0 fs/open.c:1255
       do_sys_open fs/open.c:1271 [inline]
       __do_sys_openat fs/open.c:1287 [inline]
       __se_sys_openat fs/open.c:1282 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1282
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #2 (&dquot->dq_lock){+.+.}-{3:3}:
       __mutex_lock_common+0x1e3/0x2400 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
       ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6212
       mark_dquot_dirty fs/quota/dquot.c:372 [inline]
       mark_all_dquot_dirty+0x1e3/0x400 fs/quota/dquot.c:412
       __dquot_alloc_space+0x5d0/0xe20 fs/quota/dquot.c:1752
       dquot_alloc_space_nodirty include/linux/quotaops.h:297 [inline]
       dquot_alloc_space include/linux/quotaops.h:310 [inline]
       dquot_alloc_block include/linux/quotaops.h:334 [inline]
       ext4_mb_new_blocks+0xfb1/0x4820 fs/ext4/mballoc.c:5750
       ext4_ext_map_blocks+0x18ab/0x65e0 fs/ext4/extents.c:4357
       ext4_map_blocks+0x98e/0x1b30 fs/ext4/inode.c:675
       ext4_getblk+0x176/0x670 fs/ext4/inode.c:872
       ext4_bread+0x26/0x180 fs/ext4/inode.c:925
       ext4_append+0x2be/0x560 fs/ext4/namei.c:83
       ext4_init_new_dir+0x2a2/0x940 fs/ext4/namei.c:3030
       ext4_mkdir+0x4fb/0xce0 fs/ext4/namei.c:3076
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1df/0x5b0 fs/namei.c:4098
       __do_sys_mkdirat fs/namei.c:4113 [inline]
       __se_sys_mkdirat fs/namei.c:4111 [inline]
       __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4111
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&ei->i_data_sem){++++}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ext4_map_blocks+0x33c/0x1b30 fs/ext4/inode.c:600
       ext4_append+0x232/0x560 fs/ext4/namei.c:75
       ext4_init_new_dir+0x2a2/0x940 fs/ext4/namei.c:3030
       ext4_mkdir+0x4fb/0xce0 fs/ext4/namei.c:3076
       vfs_mkdir+0x387/0x570 fs/namei.c:4073
       do_mkdirat+0x1df/0x5b0 fs/namei.c:4098
       __do_sys_mkdir fs/namei.c:4118 [inline]
       __se_sys_mkdir fs/namei.c:4116 [inline]
       __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4116
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #0 (jbd2_handle){++++}-{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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
       lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
       wait_transaction_locked+0x1bb/0x270 fs/jbd2/transaction.c:178
       add_transaction_credits+0x103/0xc80 fs/jbd2/transaction.c:242
       start_this_handle+0x74d/0x15c0 fs/jbd2/transaction.c:423
       jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
       jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:560
       ocfs2_start_trans+0x3b2/0x6f0 fs/ocfs2/journal.c:376
       ocfs2_update_inode_atime+0xed/0x5a0 fs/ocfs2/file.c:257
       ocfs2_inode_lock_atime+0x338/0x530 fs/ocfs2/dlmglue.c:2606
       ocfs2_file_read_iter+0x3c3/0xa80 fs/ocfs2/file.c:2583
       call_read_iter include/linux/fs.h:2167 [inline]
       generic_file_splice_read+0x3ef/0x5f0 fs/splice.c:311
       do_splice_to fs/splice.c:807 [inline]
       splice_direct_to_actor+0x423/0xc10 fs/splice.c:881
       do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008
       do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249
       __do_sys_sendfile64 fs/read_write.c:1317 [inline]
       __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  jbd2_handle --> sb_internal#3 --> &journal->j_trans_barrier

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&journal->j_trans_barrier);
                               lock(sb_internal#3);
                               lock(&journal->j_trans_barrier);
  lock(jbd2_handle);

 *** DEADLOCK ***

3 locks held by syz.5.2131/13152:
 #0: ffff88801bdf6460 (sb_writers#22){.+.+}-{0:0}, at: do_sendfile+0x5d9/0xeb0 fs/read_write.c:1248
 #1: ffff88801bdf6650 (sb_internal#3){.+.+}-{0:0}, at: ocfs2_update_inode_atime+0xed/0x5a0 fs/ocfs2/file.c:257
 #2: ffff88805f0dd0e8 (&journal->j_trans_barrier){.+.+}-{3:3}, at: ocfs2_start_trans+0x3a6/0x6f0 fs/ocfs2/journal.c:374

stack backtrace:
CPU: 0 PID: 13152 Comm: syz.5.2131 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 check_noncircular+0x296/0x330 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+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 wait_transaction_locked+0x1bb/0x270 fs/jbd2/transaction.c:178
 add_transaction_credits+0x103/0xc80 fs/jbd2/transaction.c:242
 start_this_handle+0x74d/0x15c0 fs/jbd2/transaction.c:423
 jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:521
 jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:560
 ocfs2_start_trans+0x3b2/0x6f0 fs/ocfs2/journal.c:376
 ocfs2_update_inode_atime+0xed/0x5a0 fs/ocfs2/file.c:257
 ocfs2_inode_lock_atime+0x338/0x530 fs/ocfs2/dlmglue.c:2606
 ocfs2_file_read_iter+0x3c3/0xa80 fs/ocfs2/file.c:2583
 call_read_iter include/linux/fs.h:2167 [inline]
 generic_file_splice_read+0x3ef/0x5f0 fs/splice.c:311
 do_splice_to fs/splice.c:807 [inline]
 splice_direct_to_actor+0x423/0xc10 fs/splice.c:881
 do_splice_direct+0x1d4/0x2f0 fs/splice.c:1008
 do_sendfile+0x5fc/0xeb0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f457b3dddd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4579637028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f457b656fa0 RCX: 00007f457b3dddd9
RDX: 0000000000000000 RSI: 000000000000000a RDI: 000000000000000a
RBP: 00007f457b473d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f457b657038 R14: 00007f457b656fa0 R15: 00007ffd558d96a8
 </TASK>
syz.5.2131 (13152) used greatest stack depth: 19000 bytes left