====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz-executor/14796 is trying to acquire lock: ffff888067150968 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:532 but task is already holding lock: ffff888067084840 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x994/0x1190 fs/ext4/inode.c:4258 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_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_map_blocks+0x8c4/0x1a50 fs/ext4/inode.c:668 ext4_getblk+0x176/0x670 fs/ext4/inode.c:872 ext4_bread+0x26/0x180 fs/ext4/inode.c:925 ext4_quota_write+0x237/0x580 fs/ext4/super.c:6623 write_blk fs/quota/quota_tree.c:64 [inline] find_free_dqentry fs/quota/quota_tree.c:307 [inline] do_insert_tree+0x1193/0x19c0 fs/quota/quota_tree.c:364 do_insert_tree+0x5c4/0x19c0 fs/quota/quota_tree.c:366 do_insert_tree+0x5c4/0x19c0 fs/quota/quota_tree.c:366 do_insert_tree+0x5c4/0x19c0 fs/quota/quota_tree.c:366 dq_insert_tree fs/quota/quota_tree.c:392 [inline] qtree_write_dquot+0x354/0x4a0 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:497 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6232 dqget+0x713/0xbb0 fs/quota/dquot.c:1010 __dquot_initialize+0x324/0xd00 fs/quota/dquot.c:1539 ext4_rmdir+0x118/0xa60 fs/ext4/namei.c:3201 vfs_rmdir+0x19d/0x410 fs/namei.c:4157 do_rmdir+0x27f/0x710 fs/namei.c:4218 __do_sys_rmdir fs/namei.c:4237 [inline] __se_sys_rmdir fs/namei.c:4235 [inline] __x64_sys_rmdir+0x45/0x50 fs/namei.c:4235 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 (&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:488 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6232 dqget+0x713/0xbb0 fs/quota/dquot.c:1010 __dquot_initialize+0x3a9/0xd00 fs/quota/dquot.c:1539 ext4_rename fs/ext4/namei.c:3882 [inline] ext4_rename2+0x6d5/0x30e0 fs/ext4/namei.c:4272 vfs_rename+0xd57/0x10f0 fs/namei.c:4840 do_renameat2+0x9e9/0xf70 fs/namei.c:4993 __do_sys_rename fs/namei.c:5039 [inline] __se_sys_rename fs/namei.c:5037 [inline] __x64_sys_rename+0x82/0x90 fs/namei.c:5037 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 (&dquot->dq_lock){+.+.}-{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+0x2c66/0x7b50 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1e5/0x2400 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:532 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6212 mark_dquot_dirty fs/quota/dquot.c:397 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:437 __dquot_free_space+0x7c3/0xb80 fs/quota/dquot.c:1964 dquot_free_space_nodirty include/linux/quotaops.h:369 [inline] dquot_free_space include/linux/quotaops.h:374 [inline] dquot_free_block include/linux/quotaops.h:385 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6164 [inline] ext4_free_blocks+0x1b1b/0x24c0 fs/ext4/mballoc.c:6294 ext4_remove_blocks fs/ext4/extents.c:2540 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2706 [inline] ext4_ext_remove_space+0x2106/0x41a0 fs/ext4/extents.c:2954 ext4_ext_truncate+0x182/0x230 fs/ext4/extents.c:4504 ext4_truncate+0xa41/0x1190 fs/ext4/inode.c:4263 ext4_evict_inode+0xb0f/0x1050 fs/ext4/inode.c:291 evict+0x4b6/0x8b0 fs/inode.c:647 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x392/0x410 fs/namei.c:4170 do_rmdir+0x27f/0x710 fs/namei.c:4218 __do_sys_unlinkat fs/namei.c:4398 [inline] __se_sys_unlinkat fs/namei.c:4392 [inline] __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392 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: &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 *** 5 locks held by syz-executor/14796: #0: ffff88805566a460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386 #1: ffff88805ee97198 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff88805ee97198 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_rmdir+0x1b0/0x710 fs/namei.c:4205 #2: ffff88805566a650 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1811 [inline] #2: ffff88805566a650 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:1928 [inline] #2: ffff88805566a650 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x41f/0x1050 fs/ext4/inode.c:245 #3: ffff888067084840 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x994/0x1190 fs/ext4/inode.c:4258 #4: ffffffff8c441798 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312 stack backtrace: CPU: 1 PID: 14796 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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+0x2c66/0x7b50 kernel/locking/lockdep.c:5012 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1e5/0x2400 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:532 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6212 mark_dquot_dirty fs/quota/dquot.c:397 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:437 __dquot_free_space+0x7c3/0xb80 fs/quota/dquot.c:1964 dquot_free_space_nodirty include/linux/quotaops.h:369 [inline] dquot_free_space include/linux/quotaops.h:374 [inline] dquot_free_block include/linux/quotaops.h:385 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6164 [inline] ext4_free_blocks+0x1b1b/0x24c0 fs/ext4/mballoc.c:6294 ext4_remove_blocks fs/ext4/extents.c:2540 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2706 [inline] ext4_ext_remove_space+0x2106/0x41a0 fs/ext4/extents.c:2954 ext4_ext_truncate+0x182/0x230 fs/ext4/extents.c:4504 ext4_truncate+0xa41/0x1190 fs/ext4/inode.c:4263 ext4_evict_inode+0xb0f/0x1050 fs/ext4/inode.c:291 evict+0x4b6/0x8b0 fs/inode.c:647 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x392/0x410 fs/namei.c:4170 do_rmdir+0x27f/0x710 fs/namei.c:4218 __do_sys_unlinkat fs/namei.c:4398 [inline] __se_sys_unlinkat fs/namei.c:4392 [inline] __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392 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: 0033:0x7f5f2edfdf77 Code: 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 b8 07 01 00 00 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:00007fffa2ead7d8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f5f2edfdf77 RDX: 0000000000000200 RSI: 00007fffa2eae980 RDI: 00000000ffffff9c RBP: 00007f5f2ee942ca R08: 0000000000008550 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000207 R12: 00007fffa2eae980 R13: 00007f5f2ee942ca R14: 0000000000079d11 R15: 00007fffa2eb0b40