EXT4-fs (loop5): mounted filesystem without journal. Opts: grpquota,journal_ioprio=0x0000000000000000,quota,,errors=continue. Quota mode: writeback. ext4 filesystem being mounted at /85/file1 supports timestamps until 2038-01-19 (0x7fffffff) ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.5.734/7714 is trying to acquire lock: ffff888021b97020 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x33c/0x1b30 fs/ext4/inode.c:600 but task is already holding lock: ffff88802501c208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x12b/0x190 fs/quota/quota_v2.c:354 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&s->s_dquot.dqio_sem){++++}-{3:3}: down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 v2_read_dquot+0x4a/0x110 fs/quota/quota_v2.c:332 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6232 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x3c3/0xcd0 fs/quota/dquot.c:1517 ext4_mkdir+0x1a5/0xce0 fs/ext4/namei.c:3059 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 (&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+0xf9/0x400 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_iomap_alloc fs/ext4/inode.c:3410 [inline] ext4_iomap_begin+0x81f/0xba0 fs/ext4/inode.c:3460 iomap_iter+0x620/0xdb0 fs/iomap/iter.c:74 __iomap_dio_rw+0xade/0x1b00 fs/iomap/direct-io.c:589 iomap_dio_rw+0x38/0x90 fs/iomap/direct-io.c:676 ext4_dio_write_iter fs/ext4/file.c:540 [inline] ext4_file_write_iter+0x12ad/0x1700 fs/ext4/file.c:660 do_iter_readv_writev+0x47e/0x5f0 fs/read_write.c:-1 do_iter_write+0x205/0x7b0 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_pwritev+0x240/0x3a0 fs/read_write.c:1025 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 (&ei->i_data_sem/2){++++}-{3:3}: 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 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x33c/0x1b30 fs/ext4/inode.c:600 ext4_getblk+0x176/0x670 fs/ext4/inode.c:872 ext4_bread+0x26/0x180 fs/ext4/inode.c:925 ext4_quota_write+0x236/0x580 fs/ext4/super.c:6623 write_blk fs/quota/quota_tree.c:64 [inline] get_free_dqblk+0x387/0x7d0 fs/quota/quota_tree.c:125 do_insert_tree+0x214/0x1970 fs/quota/quota_tree.c:335 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x361/0x4b0 fs/quota/quota_tree.c:411 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:472 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6232 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_transfer+0x1e9/0x460 fs/quota/dquot.c:2146 ext4_setattr+0x735/0x1b60 fs/ext4/inode.c:5477 notify_change+0xbcd/0xee0 fs/attr.c:505 chown_common+0x4a7/0x660 fs/open.c:680 do_fchownat+0x147/0x240 fs/open.c:711 __do_sys_lchown fs/open.c:736 [inline] __se_sys_lchown fs/open.c:734 [inline] __x64_sys_lchown+0x81/0x90 fs/open.c:734 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: &ei->i_data_sem/2 --> &dquot->dq_lock --> &s->s_dquot.dqio_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&s->s_dquot.dqio_sem); lock(&dquot->dq_lock); lock(&s->s_dquot.dqio_sem); lock(&ei->i_data_sem/2); *** DEADLOCK *** 5 locks held by syz.5.734/7714: #0: ffff88802501c460 (sb_writers#5){++++}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386 #1: ffff88807110d3b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff88807110d3b0 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: chown_common+0x3ea/0x660 fs/open.c:674 #2: ffff88807110d088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_setattr+0x728/0x1b60 fs/ext4/inode.c:5476 #3: ffff8880170a2b28 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_acquire+0x63/0x520 fs/quota/dquot.c:460 #4: ffff88802501c208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x12b/0x190 fs/quota/quota_v2.c:354 stack backtrace: CPU: 1 PID: 7714 Comm: syz.5.734 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: 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 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x33c/0x1b30 fs/ext4/inode.c:600 ext4_getblk+0x176/0x670 fs/ext4/inode.c:872 ext4_bread+0x26/0x180 fs/ext4/inode.c:925 ext4_quota_write+0x236/0x580 fs/ext4/super.c:6623 write_blk fs/quota/quota_tree.c:64 [inline] get_free_dqblk+0x387/0x7d0 fs/quota/quota_tree.c:125 do_insert_tree+0x214/0x1970 fs/quota/quota_tree.c:335 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 do_insert_tree+0x5b1/0x1970 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x361/0x4b0 fs/quota/quota_tree.c:411 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:472 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6232 dqget+0x778/0xeb0 fs/quota/dquot.c:988 dquot_transfer+0x1e9/0x460 fs/quota/dquot.c:2146 ext4_setattr+0x735/0x1b60 fs/ext4/inode.c:5477 notify_change+0xbcd/0xee0 fs/attr.c:505 chown_common+0x4a7/0x660 fs/open.c:680 do_fchownat+0x147/0x240 fs/open.c:711 __do_sys_lchown fs/open.c:736 [inline] __se_sys_lchown fs/open.c:734 [inline] __x64_sys_lchown+0x81/0x90 fs/open.c:734 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: 0033:0x7f3ffd6c8dd9 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:00007f3ffb922028 EFLAGS: 00000246 ORIG_RAX: 000000000000005e RAX: ffffffffffffffda RBX: 00007f3ffd941fa0 RCX: 00007f3ffd6c8dd9 RDX: 000000000000ee01 RSI: 000000000000ee00 RDI: 0000200000000200 RBP: 00007f3ffd75ed69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3ffd942038 R14: 00007f3ffd941fa0 R15: 00007ffde48353c8