====================================================== WARNING: possible circular locking dependency detected 5.15.188-syzkaller #0 Not tainted ------------------------------------------------------ syz.4.986/8775 is trying to acquire lock: ffff88807e843450 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_map_blocks+0x32f/0x1b30 fs/ext4/inode.c:598 but task is already holding lock: ffff888059664208 (&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:6203 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+0xaa9/0x12e0 fs/ext4/orphan.c:474 ext4_fill_super+0x9288/0x9a00 fs/ext4/super.c:4973 mount_bdev+0x287/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3014 do_mount fs/namespace.c:3357 [inline] __do_sys_mount fs/namespace.c:3565 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3542 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+0x1eb/0x2390 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:6183 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+0xf68/0x4940 fs/ext4/mballoc.c:5739 ext4_ext_map_blocks+0x146f/0x64e0 fs/ext4/extents.c:4341 ext4_map_blocks+0x981/0x1b30 fs/ext4/inode.c:673 ext4_getblk+0x16d/0x630 fs/ext4/inode.c:870 ext4_bread+0x26/0x180 fs/ext4/inode.c:923 ext4_append+0x2c3/0x560 fs/ext4/namei.c:83 ext4_add_entry+0xa34/0xf70 fs/ext4/namei.c:2511 ext4_add_nondir+0x93/0x270 fs/ext4/namei.c:2845 ext4_create+0x2e0/0x460 fs/ext4/namei.c:2891 vfs_create+0x2db/0x460 fs/namei.c:3162 do_mknodat+0x39d/0x620 fs/namei.c:3994 __do_sys_mknod fs/namei.c:4027 [inline] __se_sys_mknod fs/namei.c:4025 [inline] __x64_sys_mknod+0x8a/0xa0 fs/namei.c:4025 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x32f/0x1b30 fs/ext4/inode.c:598 ext4_getblk+0x16d/0x630 fs/ext4/inode.c:870 ext4_bread+0x26/0x180 fs/ext4/inode.c:923 ext4_quota_write+0x230/0x570 fs/ext4/super.c:6594 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:6203 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517 ext4_rmdir+0x104/0x9f0 fs/ext4/namei.c:3201 vfs_rmdir+0x1b2/0x430 fs/namei.c:4149 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_rmdir fs/namei.c:4229 [inline] __se_sys_rmdir fs/namei.c:4227 [inline] __x64_sys_rmdir+0x45/0x50 fs/namei.c:4227 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.4.986/8775: #0: ffff888059664460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:377 #1: ffff88807e8403f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff88807e8403f0 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_rmdir+0x1b2/0x710 fs/namei.c:4197 #2: ffff88807e842bd0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #2: ffff88807e842bd0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_rmdir+0xf4/0x430 fs/namei.c:4139 #3: ffff888072dfd068 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_acquire+0x63/0x520 fs/quota/dquot.c:460 #4: ffff888059664208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x12b/0x190 fs/quota/quota_v2.c:354 stack backtrace: CPU: 0 PID: 8775 Comm: syz.4.986 Not tainted 5.15.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498 ext4_map_blocks+0x32f/0x1b30 fs/ext4/inode.c:598 ext4_getblk+0x16d/0x630 fs/ext4/inode.c:870 ext4_bread+0x26/0x180 fs/ext4/inode.c:923 ext4_quota_write+0x230/0x570 fs/ext4/super.c:6594 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:6203 dqget+0x778/0xeb0 fs/quota/dquot.c:988 __dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517 ext4_rmdir+0x104/0x9f0 fs/ext4/namei.c:3201 vfs_rmdir+0x1b2/0x430 fs/namei.c:4149 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_rmdir fs/namei.c:4229 [inline] __se_sys_rmdir fs/namei.c:4227 [inline] __x64_sys_rmdir+0x45/0x50 fs/namei.c:4227 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: 0033:0x7f19e3e26929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f19e1c6d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 00007f19e404e080 RCX: 00007f19e3e26929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000080 RBP: 00007f19e3ea8ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f19e404e080 R15: 00007ffddbb11de8 EXT4-fs error (device loop4): ext4_empty_dir:3145: inode #12: block 32: comm syz.4.986: bad entry in directory: rec_len % 4 != 0 - offset=0, inode=12, rec_len=106, size=2048 fake=1 EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz.4.986: directory missing '.'