====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.661/7262 is trying to acquire lock: ffff0000fa6f20a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_acquire+0x60/0x4b8 fs/quota/dquot.c:488 but task is already holding lock: ffff0000f518c990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfec/0x125c fs/jbd2/transaction.c:461 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (jbd2_handle){++++}-{0:0}: wait_transaction_locked+0x184/0x23c fs/jbd2/transaction.c:177 add_transaction_credits+0x104/0xaf0 fs/jbd2/transaction.c:-1 start_this_handle+0x4dc/0x125c fs/jbd2/transaction.c:422 jbd2__journal_start+0x288/0x530 fs/jbd2/transaction.c:520 jbd2_journal_start+0x3c/0x4c fs/jbd2/transaction.c:559 ocfs2_start_trans+0x398/0x6f4 fs/ocfs2/journal.c:376 ocfs2_free_cached_clusters fs/ocfs2/alloc.c:6506 [inline] ocfs2_run_deallocs+0xf08/0x14b0 fs/ocfs2/alloc.c:6569 ocfs2_commit_truncate+0x137c/0x1980 fs/ocfs2/alloc.c:7375 ocfs2_truncate_file+0xc04/0x14dc fs/ocfs2/file.c:505 ocfs2_setattr+0x12a0/0x1950 fs/ocfs2/file.c:1212 notify_change+0xb5c/0xe20 fs/attr.c:499 do_truncate+0x188/0x20c fs/open.c:65 do_sys_ftruncate+0x284/0x318 fs/open.c:193 __do_sys_ftruncate fs/open.c:204 [inline] __se_sys_ftruncate fs/open.c:202 [inline] __arm64_sys_ftruncate+0x60/0x74 fs/open.c:202 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 -> #3 (&journal->j_trans_barrier){.+.+}-{3:3}: down_read+0x64/0x300 kernel/locking/rwsem.c:1520 ocfs2_start_trans+0x38c/0x6f4 fs/ocfs2/journal.c:374 ocfs2_block_group_alloc fs/ocfs2/suballoc.c:703 [inline] ocfs2_reserve_suballoc_bits+0x6a8/0x3d40 fs/ocfs2/suballoc.c:850 ocfs2_reserve_new_inode+0x3c0/0xb58 fs/ocfs2/suballoc.c:1090 ocfs2_mknod+0x7d8/0x212c fs/ocfs2/namei.c:304 ocfs2_create+0x19c/0x51c fs/ocfs2/namei.c:676 lookup_open fs/namei.c:3533 [inline] open_last_lookups fs/namei.c:3601 [inline] path_openat+0xda8/0x27a0 fs/namei.c:3835 do_filp_open+0x198/0x38c fs/namei.c:3865 do_sys_openat2+0x134/0x3fc fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x11c/0x150 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 -> #2 (sb_internal#3){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1897 [inline] sb_start_intwrite include/linux/fs.h:2019 [inline] ocfs2_start_trans+0x20c/0x6f4 fs/ocfs2/journal.c:372 ocfs2_acquire_dquot+0x5d0/0xab0 fs/ocfs2/quota_global.c:848 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ocfs2_get_init_inode+0x140/0x1b4 fs/ocfs2/namei.c:202 ocfs2_mknod+0x7f8/0x212c fs/ocfs2/namei.c:311 ocfs2_create+0x19c/0x51c fs/ocfs2/namei.c:676 lookup_open fs/namei.c:3533 [inline] open_last_lookups fs/namei.c:3601 [inline] path_openat+0xda8/0x27a0 fs/namei.c:3835 do_filp_open+0x198/0x38c fs/namei.c:3865 do_sys_openat2+0x134/0x3fc fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x11c/0x150 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 -> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}: down_write+0x5c/0x88 kernel/locking/rwsem.c:1573 ocfs2_create_local_dquot+0x140/0x1444 fs/ocfs2/quota_local.c:1224 ocfs2_acquire_dquot+0x6dc/0xab0 fs/ocfs2/quota_global.c:871 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ocfs2_get_init_inode+0x140/0x1b4 fs/ocfs2/namei.c:202 ocfs2_mknod+0x7f8/0x212c fs/ocfs2/namei.c:311 ocfs2_create+0x19c/0x51c fs/ocfs2/namei.c:676 lookup_open fs/namei.c:3533 [inline] open_last_lookups fs/namei.c:3601 [inline] path_openat+0xda8/0x27a0 fs/namei.c:3835 do_filp_open+0x198/0x38c fs/namei.c:3865 do_sys_openat2+0x134/0x3fc fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __arm64_sys_openat+0x11c/0x150 fs/open.c:1347 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3504/0x7280 kernel/locking/lockdep.c:5171 lock_acquire+0x210/0x63c kernel/locking/lockdep.c:5790 __mutex_lock_common+0x1a0/0x1f88 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 dquot_acquire+0x60/0x4b8 fs/quota/dquot.c:488 ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6844 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ext4_unlink+0x150/0x714 fs/ext4/namei.c:3365 vfs_unlink+0x2e0/0x4f4 fs/namei.c:4377 do_unlinkat+0x318/0x504 fs/namei.c:4445 __do_sys_unlinkat fs/namei.c:4488 [inline] __se_sys_unlinkat fs/namei.c:4481 [inline] __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4481 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> &journal->j_trans_barrier --> jbd2_handle Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(jbd2_handle); lock(&journal->j_trans_barrier); lock(jbd2_handle); lock(&dquot->dq_lock); *** DEADLOCK *** 4 locks held by syz.2.661/7262: #0: ffff0000dcf62460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e1ae6850 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:799 [inline] #1: ffff0000e1ae6850 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x184/0x504 fs/namei.c:4428 #2: ffff0000e1ae5440 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #2: ffff0000e1ae5440 (&sb->s_type->i_mutex_key#10){++++}-{3:3}, at: vfs_unlink+0xd0/0x4f4 fs/namei.c:4366 #3: ffff0000f518c990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfec/0x125c fs/jbd2/transaction.c:461 stack backtrace: CPU: 1 PID: 7262 Comm: syz.2.661 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2088 check_noncircular+0x290/0x370 kernel/locking/lockdep.c:2215 check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3504/0x7280 kernel/locking/lockdep.c:5171 lock_acquire+0x210/0x63c kernel/locking/lockdep.c:5790 __mutex_lock_common+0x1a0/0x1f88 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 dquot_acquire+0x60/0x4b8 fs/quota/dquot.c:488 ext4_acquire_dquot+0x270/0x420 fs/ext4/super.c:6844 dqget+0x638/0xa98 fs/quota/dquot.c:1013 __dquot_initialize+0x2e4/0xb30 fs/quota/dquot.c:1542 dquot_initialize+0x24/0x34 fs/quota/dquot.c:1604 ext4_unlink+0x150/0x714 fs/ext4/namei.c:3365 vfs_unlink+0x2e0/0x4f4 fs/namei.c:4377 do_unlinkat+0x318/0x504 fs/namei.c:4445 __do_sys_unlinkat fs/namei.c:4488 [inline] __se_sys_unlinkat fs/namei.c:4481 [inline] __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4481 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589