loop1: detected capacity change from 0 to 512 ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.3256/11758 is trying to acquire lock: ffff8880520ae5e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 but task is already holding lock: ffff8880521f8288 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x9ae/0x12a0 fs/ext4/inode.c:4300 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+0x338/0x1a90 fs/ext4/inode.c:606 ext4_getblk+0x1c5/0x720 fs/ext4/inode.c:892 ext4_bread+0x26/0x170 fs/ext4/inode.c:948 ext4_quota_write+0x237/0x580 fs/ext4/super.c:7223 write_blk fs/quota/quota_tree.c:70 [inline] get_free_dqblk+0x2dc/0x630 fs/quota/quota_tree.c:136 do_insert_tree+0x22b/0x1060 fs/quota/quota_tree.c:347 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 do_insert_tree+0x9f5/0x1060 fs/quota/quota_tree.c:402 dq_insert_tree fs/quota/quota_tree.c:432 [inline] qtree_write_dquot+0x49b/0x5d0 fs/quota/quota_tree.c:451 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:361 dquot_acquire+0x2d5/0x520 fs/quota/dquot.c:500 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6844 dqget+0x713/0xbb0 fs/quota/dquot.c:1013 __dquot_initialize+0x3a9/0xd00 fs/quota/dquot.c:1542 ext4_process_orphan+0x4c/0x2e0 fs/ext4/orphan.c:327 ext4_orphan_cleanup+0xdfe/0x1650 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5578 [inline] ext4_fill_super+0x6cd4/0x77b0 fs/ext4/super.c:5700 get_tree_bdev+0x3e6/0x610 fs/super.c:1377 vfs_get_tree+0x88/0x270 fs/super.c:1584 do_new_mount+0x247/0xa50 fs/namespace.c:3104 do_mount fs/namespace.c:3475 [inline] __do_sys_mount fs/namespace.c:3683 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3660 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 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:491 ext4_acquire_dquot+0x2e3/0x4a0 fs/ext4/super.c:6844 dqget+0x713/0xbb0 fs/quota/dquot.c:1013 __dquot_initialize+0x324/0xd00 fs/quota/dquot.c:1542 ext4_process_orphan+0x4c/0x2e0 fs/ext4/orphan.c:327 ext4_orphan_cleanup+0xdfe/0x1650 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5578 [inline] ext4_fill_super+0x6cd4/0x77b0 fs/ext4/super.c:5700 get_tree_bdev+0x3e6/0x610 fs/super.c:1377 vfs_get_tree+0x88/0x270 fs/super.c:1584 do_new_mount+0x247/0xa50 fs/namespace.c:3104 do_mount fs/namespace.c:3475 [inline] __do_sys_mount fs/namespace.c:3683 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3660 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&dquot->dq_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xb40 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6824 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0x1e3/0x400 fs/quota/dquot.c:440 __dquot_free_space+0x7f8/0xbc0 fs/quota/dquot.c:1967 dquot_free_space_nodirty include/linux/quotaops.h:372 [inline] dquot_free_space include/linux/quotaops.h:377 [inline] dquot_free_block include/linux/quotaops.h:388 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6168 [inline] ext4_free_blocks+0x1bda/0x2650 fs/ext4/mballoc.c:6298 ext4_remove_blocks fs/ext4/extents.c:2541 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2707 [inline] ext4_ext_remove_space+0x1e82/0x43d0 fs/ext4/extents.c:2955 ext4_ext_truncate+0x213/0x370 fs/ext4/extents.c:4499 ext4_truncate+0xa5b/0x12a0 fs/ext4/inode.c:4305 ext4_evict_inode+0xb21/0x10e0 fs/ext4/inode.c:288 evict+0x4b2/0x9d0 fs/inode.c:703 ext4_orphan_cleanup+0xdfe/0x1650 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5578 [inline] ext4_fill_super+0x6cd4/0x77b0 fs/ext4/super.c:5700 get_tree_bdev+0x3e6/0x610 fs/super.c:1377 vfs_get_tree+0x88/0x270 fs/super.c:1584 do_new_mount+0x247/0xa50 fs/namespace.c:3104 do_mount fs/namespace.c:3475 [inline] __do_sys_mount fs/namespace.c:3683 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3660 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 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.1.3256/11758: #0: ffff88804cbda0e0 (&type->s_umount_key#27/1){+.+.}-{3:3}, at: alloc_super+0x1fb/0x930 fs/super.c:228 #1: ffff88804cbda650 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline] #1: ffff88804cbda650 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:2019 [inline] #1: ffff88804cbda650 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x431/0x10e0 fs/ext4/inode.c:242 #2: ffff8880521f8288 (&ei->i_data_sem/2){++++}-{3:3}, at: ext4_truncate+0x9ae/0x12a0 fs/ext4/inode.c:4300 #3: ffffffff8dc750c8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8dc750c8 (dquot_srcu){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline] #3: ffffffff8dc750c8 (dquot_srcu){....}-{0:0}, at: __dquot_free_space+0x172/0xbc0 fs/quota/dquot.c:1940 stack backtrace: CPU: 0 PID: 11758 Comm: syz.1.3256 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2215 check_prev_add kernel/locking/lockdep.c:3162 [inline] check_prevs_add kernel/locking/lockdep.c:3281 [inline] validate_chain kernel/locking/lockdep.c:3897 [inline] __lock_acquire+0x3a03/0x7ea0 kernel/locking/lockdep.c:5171 lock_acquire+0x1bc/0x4a0 kernel/locking/lockdep.c:5790 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12d/0xb40 kernel/locking/mutex.c:747 dquot_commit+0x5a/0x410 fs/quota/dquot.c:535 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6824 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0x1e3/0x400 fs/quota/dquot.c:440 __dquot_free_space+0x7f8/0xbc0 fs/quota/dquot.c:1967 dquot_free_space_nodirty include/linux/quotaops.h:372 [inline] dquot_free_space include/linux/quotaops.h:377 [inline] dquot_free_block include/linux/quotaops.h:388 [inline] ext4_mb_clear_bb fs/ext4/mballoc.c:6168 [inline] ext4_free_blocks+0x1bda/0x2650 fs/ext4/mballoc.c:6298 ext4_remove_blocks fs/ext4/extents.c:2541 [inline] ext4_ext_rm_leaf fs/ext4/extents.c:2707 [inline] ext4_ext_remove_space+0x1e82/0x43d0 fs/ext4/extents.c:2955 ext4_ext_truncate+0x213/0x370 fs/ext4/extents.c:4499 ext4_truncate+0xa5b/0x12a0 fs/ext4/inode.c:4305 ext4_evict_inode+0xb21/0x10e0 fs/ext4/inode.c:288 evict+0x4b2/0x9d0 fs/inode.c:703 ext4_orphan_cleanup+0xdfe/0x1650 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5578 [inline] ext4_fill_super+0x6cd4/0x77b0 fs/ext4/super.c:5700 get_tree_bdev+0x3e6/0x610 fs/super.c:1377 vfs_get_tree+0x88/0x270 fs/super.c:1584 do_new_mount+0x247/0xa50 fs/namespace.c:3104 do_mount fs/namespace.c:3475 [inline] __do_sys_mount fs/namespace.c:3683 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3660 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5bacba0d8a Code: 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 49 89 ca b8 a5 00 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:00007f5bad9b4e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f5bad9b4ee0 RCX: 00007f5bacba0d8a RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 00007f5bad9b4ea0 RBP: 0000200000000040 R08: 00007f5bad9b4ee0 R09: 0000000003018012 R10: 0000000003018012 R11: 0000000000000246 R12: 00002000000001c0 R13: 00007f5bad9b4ea0 R14: 000000000000052a R15: 0000200000001800 EXT4-fs error (device loop1): ext4_do_update_inode:5312: inode #16: comm syz.1.3256: corrupted inode contents EXT4-fs error (device loop1): ext4_dirty_inode:6199: inode #16: comm syz.1.3256: mark_inode_dirty error EXT4-fs error (device loop1): ext4_do_update_inode:5312: inode #16: comm syz.1.3256: corrupted inode contents EXT4-fs error (device loop1): __ext4_ext_dirty:202: inode #16: comm syz.1.3256: mark_inode_dirty error EXT4-fs error (device loop1): ext4_do_update_inode:5312: inode #16: comm syz.1.3256: corrupted inode contents EXT4-fs error (device loop1): __ext4_ext_dirty:202: inode #16: comm syz.1.3256: mark_inode_dirty error EXT4-fs error (device loop1): ext4_do_update_inode:5312: inode #16: comm syz.1.3256: corrupted inode contents EXT4-fs error (device loop1): ext4_truncate:4328: inode #16: comm syz.1.3256: mark_inode_dirty error EXT4-fs error (device loop1): ext4_evict_inode:292: comm syz.1.3256: couldn't truncate inode 16 (err -117) EXT4-fs (loop1): 1 orphan inode deleted EXT4-fs (loop1): mounted filesystem without journal. Quota mode: writeback. ext4 filesystem being mounted at /647/file1 supports timestamps until 2038-01-19 (0x7fffffff)