loop0: detected capacity change from 0 to 512 ext4 filesystem being mounted at /root/syzkaller.WZtAmN/183/file0 supports timestamps until 2038-01-19 (0x7fffffff) ====================================================== WARNING: possible circular locking dependency detected 6.1.138-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor559/4690 is trying to acquire lock: ffff8880707853e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 but task is already holding lock: ffff8880705970e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x903/0x1b60 fs/ext4/inode.c:672 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&ei->i_data_sem/2){++++}-{3:3}: down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520 ext4_map_blocks+0x316/0x1b60 fs/ext4/inode.c:604 ext4_getblk+0x1ab/0x6d0 fs/ext4/inode.c:890 ext4_bread+0x26/0x170 fs/ext4/inode.c:946 ext4_quota_read+0x180/0x380 fs/ext4/super.c:7143 read_blk fs/quota/quota_tree.c:61 [inline] find_tree_dqentry+0x1cd/0xf30 fs/quota/quota_tree.c:671 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_tree_dqentry+0x6b0/0xf30 fs/quota/quota_tree.c:698 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x558/0x7f0 fs/quota/quota_tree.c:736 v2_read_dquot+0xc0/0x110 fs/quota/quota_v2.c:336 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6798 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x328/0xcb0 fs/quota/dquot.c:1517 ext4_process_orphan+0x54/0x300 fs/ext4/orphan.c:329 ext4_orphan_cleanup+0xbd3/0x1400 fs/ext4/orphan.c:474 __ext4_fill_super fs/ext4/super.c:5523 [inline] ext4_fill_super+0x7b5e/0x80d0 fs/ext4/super.c:5654 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3057 do_mount fs/namespace.c:3400 [inline] __do_sys_mount fs/namespace.c:3608 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3585 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 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:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6798 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517 ext4_mkdir+0x16c/0xc50 fs/ext4/namei.c:3059 vfs_mkdir+0x387/0x570 fs/namei.c:4106 do_mkdirat+0x1d0/0x430 fs/namei.c:4131 __do_sys_mkdir fs/namei.c:4151 [inline] __se_sys_mkdir fs/namei.c:4149 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: 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+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6778 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5fc/0xe60 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xf74/0x4720 fs/ext4/mballoc.c:5727 ext4_ext_map_blocks+0x143c/0x66d0 fs/ext4/extents.c:4339 ext4_map_blocks+0x9d1/0x1b60 fs/ext4/inode.c:679 ext4_getblk+0x1ab/0x6d0 fs/ext4/inode.c:890 ext4_bread+0x26/0x170 fs/ext4/inode.c:946 ext4_append+0x2c3/0x560 fs/ext4/namei.c:83 ext4_init_new_dir+0x2b8/0x570 fs/ext4/namei.c:3030 ext4_mkdir+0x47d/0xc50 fs/ext4/namei.c:3076 vfs_mkdir+0x387/0x570 fs/namei.c:4106 do_mkdirat+0x1d0/0x430 fs/namei.c:4131 __do_sys_mkdir fs/namei.c:4151 [inline] __se_sys_mkdir fs/namei.c:4149 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Chain exists of: &dquot->dq_lock --> &s->s_dquot.dqio_sem --> &ei->i_data_sem/2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->i_data_sem/2); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); lock(&dquot->dq_lock); *** DEADLOCK *** 4 locks held by syz-executor559/4690: #0: ffff88802fa1e460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:393 #1: ffff888073ad1810 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff888073ad1810 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3876 #2: ffff8880705970e0 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x903/0x1b60 fs/ext4/inode.c:672 #3: ffffffff8ca74b08 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8ca74b08 (dquot_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline] #3: ffffffff8ca74b08 (dquot_srcu){....}-{0:0}, at: __dquot_alloc_space+0x173/0xe60 fs/quota/dquot.c:1716 stack backtrace: CPU: 0 PID: 4690 Comm: syz-executor559 Not tainted 6.1.138-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 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+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6778 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_alloc_space+0x5fc/0xe60 fs/quota/dquot.c:1752 dquot_alloc_space_nodirty include/linux/quotaops.h:300 [inline] dquot_alloc_space include/linux/quotaops.h:313 [inline] dquot_alloc_block include/linux/quotaops.h:337 [inline] ext4_mb_new_blocks+0xf74/0x4720 fs/ext4/mballoc.c:5727 ext4_ext_map_blocks+0x143c/0x66d0 fs/ext4/extents.c:4339 ext4_map_blocks+0x9d1/0x1b60 fs/ext4/inode.c:679 ext4_getblk+0x1ab/0x6d0 fs/ext4/inode.c:890 ext4_bread+0x26/0x170 fs/ext4/inode.c:946 ext4_append+0x2c3/0x560 fs/ext4/namei.c:83 ext4_init_new_dir+0x2b8/0x570 fs/ext4/namei.c:3030 ext4_mkdir+0x47d/0xc50 fs/ext4/namei.c:3076 vfs_mkdir+0x387/0x570 fs/namei.c:4106 do_mkdirat+0x1d0/0x430 fs/namei.c:4131 __do_sys_mkdir fs/namei.c:4151 [inline] __se_sys_mkdir fs/namei.c:4149 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f3feddcc3a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff889e1cd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f3feddcc3a9 RDX: 00007f3feddcb540 RSI: 0000000000000000 RDI: 0000200000000400 RBP: 00002000000008c0 R08: 0000000000000514 R09: 0000200000001200 R10: 00007fff889e1ba0 R11: 0000000000000246 R12: 00007fff889e1d0c R13: 00000000000000b7 R14: 431bde82d7b634db R15: 00007fff889e1d40