EXT4-fs error (device loop4): ext4_readdir:263: inode #2: block 3: comm syz-executor: path /174/file0: bad entry in directory: rec_len is smaller than minimal - offset=60, inode=113, rec_len=0, size=2048 fake=0 ====================================================== WARNING: possible circular locking dependency detected 5.15.185-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor/4173 is trying to acquire lock: ffff888061c44268 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507 but task is already holding lock: ffff888061e62060 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x96d/0x10d0 fs/ext4/inode.c:4245 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+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_read+0x1b3/0x3a0 fs/ext4/super.c:6545 read_blk fs/quota/quota_tree.c:55 [inline] find_tree_dqentry+0x188/0xb30 fs/quota/quota_tree.c:617 find_tree_dqentry+0x3eb/0xb30 fs/quota/quota_tree.c:635 find_tree_dqentry+0x3eb/0xb30 fs/quota/quota_tree.c:635 find_tree_dqentry+0x3eb/0xb30 fs/quota/quota_tree.c:635 find_dqentry fs/quota/quota_tree.c:647 [inline] qtree_read_dquot+0x13c/0x680 fs/quota/quota_tree.c:667 v2_read_dquot+0xc0/0x110 fs/quota/quota_v2.c:333 dquot_acquire+0x152/0x520 fs/quota/dquot.c:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6200 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:4975 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:3010 do_mount fs/namespace.c:3353 [inline] __do_sys_mount fs/namespace.c:3561 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3538 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:463 ext4_acquire_dquot+0x2d9/0x4a0 fs/ext4/super.c:6200 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:4975 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:3010 do_mount fs/namespace.c:3353 [inline] __do_sys_mount fs/namespace.c:3561 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3538 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+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __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:6180 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_free_space+0x7ca/0xb90 fs/quota/dquot.c:1942 dquot_free_space_nodirty include/linux/quotaops.h:376 [inline] dquot_free_space include/linux/quotaops.h:381 [inline] dquot_free_block include/linux/quotaops.h:392 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6156 [inline] ext4_free_blocks+0x1af5/0x2480 fs/ext4/mballoc.c:6286 ext4_remove_blocks fs/ext4/extents.c:2523 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2689 [inline] ext4_ext_remove_space+0x1eaa/0x4390 fs/ext4/extents.c:2937 ext4_ext_truncate+0x192/0x240 fs/ext4/extents.c:4471 ext4_truncate+0x9f1/0x10d0 fs/ext4/inode.c:4250 ext4_evict_inode+0xb43/0x1080 fs/ext4/inode.c:289 evict+0x485/0x870 fs/inode.c:647 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x3b4/0x430 fs/namei.c:4162 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_unlinkat fs/namei.c:4390 [inline] __se_sys_unlinkat fs/namei.c:4384 [inline] __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4384 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/4173: #0: ffff88807e30e460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:377 #1: ffff888061e67198 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:822 [inline] #1: ffff888061e67198 (&type->i_mutex_dir_key#4/1){+.+.}-{3:3}, at: do_rmdir+0x1b2/0x710 fs/namei.c:4197 #2: ffff88807e30e650 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1811 [inline] #2: ffff88807e30e650 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:1928 [inline] #2: ffff88807e30e650 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x444/0x1080 fs/ext4/inode.c:243 #3: ffff888061e62060 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x96d/0x10d0 fs/ext4/inode.c:4245 #4: ffffffff8c23fd58 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 0 PID: 4173 Comm: syz-executor Not tainted 5.15.185-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 __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:6180 mark_dquot_dirty fs/quota/dquot.c:372 [inline] mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412 __dquot_free_space+0x7ca/0xb90 fs/quota/dquot.c:1942 dquot_free_space_nodirty include/linux/quotaops.h:376 [inline] dquot_free_space include/linux/quotaops.h:381 [inline] dquot_free_block include/linux/quotaops.h:392 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6156 [inline] ext4_free_blocks+0x1af5/0x2480 fs/ext4/mballoc.c:6286 ext4_remove_blocks fs/ext4/extents.c:2523 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2689 [inline] ext4_ext_remove_space+0x1eaa/0x4390 fs/ext4/extents.c:2937 ext4_ext_truncate+0x192/0x240 fs/ext4/extents.c:4471 ext4_truncate+0x9f1/0x10d0 fs/ext4/inode.c:4250 ext4_evict_inode+0xb43/0x1080 fs/ext4/inode.c:289 evict+0x485/0x870 fs/inode.c:647 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x3b4/0x430 fs/namei.c:4162 do_rmdir+0x295/0x710 fs/namei.c:4210 __do_sys_unlinkat fs/namei.c:4390 [inline] __se_sys_unlinkat fs/namei.c:4384 [inline] __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4384 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: 0033:0x7f2c4cf74f07 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 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:00007ffdd151efe8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f2c4cf74f07 RDX: 0000000000000200 RSI: 00007ffdd1520190 RDI: 00000000ffffff9c RBP: 00007f2c4cff7925 R08: 000055558df7b66b R09: 0000000000000000 R10: 0000000000001000 R11: 0000000000000207 R12: 00007ffdd1520190 R13: 00007f2c4cff7925 R14: 0000000000022b8b R15: 00007ffdd1522350 EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.' EXT4-fs warning (device loop4): ext4_empty_dir:3147: inode #12: comm syz-executor: directory missing '.'