EXT4-fs (loop6): mounted filesystem without journal. Quota mode: writeback. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.6.1017/7546 is trying to acquire lock: ffff888072cbd228 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 but task is already holding lock: ffff888074f070e0 (&ei->i_data_sem/1){+.+.}-{3:3}, at: swap_inode_boot_loader+0x571/0x10f0 fs/ext4/ioctl.c:426 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ei->i_data_sem/1){+.+.}-{3:3}: down_write_nested+0x39/0x60 kernel/locking/rwsem.c:1689 swap_inode_boot_loader+0x571/0x10f0 fs/ext4/ioctl.c:426 __ext4_ioctl fs/ext4/ioctl.c:1433 [inline] ext4_ioctl+0x1e66/0x4120 fs/ext4/ioctl.c:1623 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #2 (&ei->i_data_sem/2){++++}-{3:3}: down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ext4_map_blocks+0x914/0x1a90 fs/ext4/inode.c:674 ext4_getblk+0x1c5/0x720 fs/ext4/inode.c:892 ext4_bread+0x26/0x170 fs/ext4/inode.c:948 ext4_quota_write+0x237/0x580 fs/ext4/super.c:7228 write_blk fs/quota/quota_tree.c:70 [inline] find_free_dqentry+0x68c/0xc30 fs/quota/quota_tree.c:318 do_insert_tree+0x717/0x1060 fs/quota/quota_tree.c:400 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x49b/0x5d0 fs/quota/quota_tree.c:451 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:361 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:500 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6837 dqget+0x713/0xbb0 fs/quota/dquot.c:1013 __dquot_initialize+0x3a9/0xd00 fs/quota/dquot.c:1542 ext4_mkdir+0x198/0xc90 fs/ext4/namei.c:3061 vfs_mkdir+0x386/0x570 fs/namei.c:4157 do_mkdirat+0x1d8/0x440 fs/namei.c:4182 __do_sys_mkdirat fs/namei.c:4197 [inline] __se_sys_mkdirat fs/namei.c:4195 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4195 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #1 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520 v2_read_dquot+0x4a/0x110 fs/quota/quota_v2.c:335 dquot_acquire+0x152/0x520 fs/quota/dquot.c:491 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6837 dqget+0x713/0xbb0 fs/quota/dquot.c:1013 __dquot_initialize+0x3a9/0xd00 fs/quota/dquot.c:1542 ext4_mkdir+0x198/0xc90 fs/ext4/namei.c:3061 vfs_mkdir+0x386/0x570 fs/namei.c:4157 do_mkdirat+0x1d8/0x440 fs/namei.c:4182 __do_sys_mkdirat fs/namei.c:4197 [inline] __se_sys_mkdirat fs/namei.c:4195 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4195 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #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+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xae0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6817 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:440 __dquot_alloc_space+0x5f6/0xe50 fs/quota/dquot.c:1777 dquot_alloc_space_nodirty include/linux/quotaops.h:293 [inline] dquot_alloc_space+0x1e/0x50 include/linux/quotaops.h:306 swap_inode_boot_loader+0xe76/0x10f0 fs/ext4/ioctl.c:494 __ext4_ioctl fs/ext4/ioctl.c:1433 [inline] ext4_ioctl+0x1e66/0x4120 fs/ext4/ioctl.c:1623 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> &ei->i_data_sem/2 --> &ei->i_data_sem/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem/1); lock(&ei->i_data_sem/2); lock(&ei->i_data_sem/1); lock(&dquot->dq_lock); *** DEADLOCK *** 7 locks held by syz.6.1017/7546: #0: ffff88805deba460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:446 #1: ffff888053702c20 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff888053702c20 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: lock_two_nondirectories+0xf7/0x150 fs/inode.c:1208 #2: ffff888074f07258 (&sb->s_type->i_mutex_key#9/4){+.+.}-{3:3}, at: swap_inode_boot_loader+0x70/0x10f0 fs/ext4/ioctl.c:385 #3: ffff888053702dc0 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:809 [inline] #3: ffff888053702dc0 (mapping.invalidate_lock#2){++++}-{3:3}, at: swap_inode_boot_loader+0x39f/0x10f0 fs/ext4/ioctl.c:402 #4: ffff888053702aa8 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_double_down_write_data_sem+0x28/0x40 fs/ext4/move_extent.c:-1 #5: ffff888074f070e0 (&ei->i_data_sem/1){+.+.}-{3:3}, at: swap_inode_boot_loader+0x571/0x10f0 fs/ext4/ioctl.c:426 #6: ffffffff8da74c48 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #6: ffffffff8da74c48 (dquot_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline] #6: ffffffff8da74c48 (dquot_srcu){....}-{0:0}, at: __dquot_alloc_space+0x16e/0xe50 fs/quota/dquot.c:1741 stack backtrace: CPU: 0 PID: 7546 Comm: syz.6.1017 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x2f8/0x400 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+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xae0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6817 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:440 __dquot_alloc_space+0x5f6/0xe50 fs/quota/dquot.c:1777 dquot_alloc_space_nodirty include/linux/quotaops.h:293 [inline] dquot_alloc_space+0x1e/0x50 include/linux/quotaops.h:306 swap_inode_boot_loader+0xe76/0x10f0 fs/ext4/ioctl.c:494 __ext4_ioctl fs/ext4/ioctl.c:1433 [inline] ext4_ioctl+0x1e66/0x4120 fs/ext4/ioctl.c:1623 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6cec79e1d9 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:00007f6ced6ae028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6ceca25fa0 RCX: 00007f6cec79e1d9 RDX: 0000000000000000 RSI: 0000000000006611 RDI: 0000000000000005 RBP: 00007f6cec835888 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6ceca26038 R14: 00007f6ceca25fa0 R15: 00007fff958e23e8