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Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/3c5e7318955b/disk-9e947d96.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b9f0f48a2f8b/vmlinux-9e947d96.xz kernel image: https://storage.googleapis.com/syzbot-assets/ddb2172ffb17/bzImage-9e947d96.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d40725440a13ae53e0c4@syzkaller.appspotmail.com EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. ext4 filesystem being mounted at /87/file1 supports timestamps until 2038-01-19 (0x7fffffff) ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.6.3297/16861 is trying to acquire lock: ffff888054410960 (&dquot->dq_lock){+.+.}-{4:4}, at: wait_on_dquot fs/quota/dquot.c:357 [inline] ffff888054410960 (&dquot->dq_lock){+.+.}-{4:4}, at: dqget+0x69d/0xbd0 fs/quota/dquot.c:997 but task is already holding lock: ffff888076702500 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x891/0x1df0 fs/ext4/inode.c:6061 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #10 (&ei->xattr_sem){++++}-{4:4}: down_read+0x45/0x320 kernel/locking/rwsem.c:1574 ext4_readpage_inline+0x36/0x6a0 fs/ext4/inline.c:548 ext4_read_folio+0x15e/0x520 fs/ext4/readpage.c:330 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2520 filemap_create_folio mm/filemap.c:2658 [inline] filemap_get_pages+0xc86/0x1ec0 mm/filemap.c:2720 filemap_read+0x421/0x11e0 mm/filemap.c:2824 ext4_file_read_iter+0x553/0xad0 fs/ext4/file.c:-1 __kernel_read+0x4ca/0x960 fs/read_write.c:532 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline] ima_calc_file_hash+0x451/0x890 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x51b/0xa00 security/integrity/ima/ima_api.c:300 process_measurement+0x1272/0x1c10 security/integrity/ima/ima_main.c:425 ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685 security_file_post_open+0xb3/0x260 security/security.c:2755 do_open fs/namei.c:4847 [inline] path_openat+0x174c/0x20f0 fs/namei.c:5010 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1464 [inline] __se_sys_openat fs/open.c:1459 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1459 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #9 (mapping.invalidate_lock#2){++++}-{4:4}: down_read+0x45/0x320 kernel/locking/rwsem.c:1574 filemap_invalidate_lock_shared include/linux/fs.h:1089 [inline] do_page_cache_ra mm/readahead.c:347 [inline] page_cache_ra_order+0xb37/0xee0 mm/readahead.c:558 do_sync_mmap_readahead+0x75e/0x990 mm/filemap.c:3443 filemap_fault+0x7d9/0x13b0 mm/filemap.c:3597 __do_fault+0x138/0x2a0 mm/memory.c:5565 do_read_fault mm/memory.c:6000 [inline] do_fault mm/memory.c:6134 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0x1a53/0x3750 mm/memory.c:6876 do_user_addr_fault+0x7f6/0x1480 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] copy_from_user_iter lib/iov_iter.c:67 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:302 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] __copy_from_iter lib/iov_iter.c:261 [inline] _copy_from_iter+0x216/0x1660 lib/iov_iter.c:272 copy_from_iter include/linux/uio.h:228 [inline] copy_from_iter_full include/linux/uio.h:245 [inline] skb_do_copy_data_nocache include/net/sock.h:2331 [inline] skb_copy_to_page_nocache include/net/sock.h:2357 [inline] tcp_sendmsg_locked+0x20cf/0x5400 net/ipv4/tcp.c:1310 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1451 sock_sendmsg_nosec+0x10e/0x180 net/socket.c:801 __sock_sendmsg net/socket.c:815 [inline] sock_write_iter+0x2de/0x3e0 net/socket.c:1266 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #8 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x41/0x100 net/core/sock.c:3865 lock_sock include/net/sock.h:1715 [inline] inet_shutdown+0x6a/0x390 net/ipv4/af_inet.c:913 nbd_mark_nsock_dead+0x2cb/0x550 drivers/block/nbd.c:319 recv_work+0x1cee/0x1e10 drivers/block/nbd.c:1030 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #7 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 nbd_handle_cmd drivers/block/nbd.c:1143 [inline] nbd_queue_rq+0x373/0xff0 drivers/block/nbd.c:1207 blk_mq_dispatch_rq_list+0x499/0x1990 block/blk-mq.c:2130 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xd36/0x1580 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_work_fn+0x167/0x2f0 block/blk-mq.c:2545 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #6 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 nbd_queue_rq+0xc1/0xff0 drivers/block/nbd.c:1199 blk_mq_dispatch_rq_list+0x499/0x1990 block/blk-mq.c:2130 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xd36/0x1580 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_work_fn+0x167/0x2f0 block/blk-mq.c:2545 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #5 (set->srcu){.+.+}-{0:0}: srcu_lock_sync include/linux/srcu.h:210 [inline] __synchronize_srcu+0xc9/0x2e0 kernel/rcu/srcutree.c:1462 elevator_switch+0x1e8/0x7b0 block/elevator.c:576 elevator_change+0x2fa/0x480 block/elevator.c:681 elevator_set_default+0x375/0x440 block/elevator.c:754 blk_register_queue+0x3f3/0x4e0 block/blk-sysfs.c:992 __add_disk+0x6b8/0xdb0 block/genhd.c:531 add_disk_fwnode+0x100/0x3a0 block/genhd.c:600 add_disk include/linux/blkdev.h:798 [inline] nbd_dev_add+0x733/0xb60 drivers/block/nbd.c:2026 nbd_init+0x168/0x1f0 drivers/block/nbd.c:2743 do_one_initcall+0x250/0x870 init/main.c:1362 do_initcall_level+0x10a/0x1a0 init/main.c:1424 do_initcalls+0x59/0xa0 init/main.c:1440 kernel_init_freeable+0x29d/0x3e0 init/main.c:1675 kernel_init+0x22/0x1d0 init/main.c:1565 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #4 (&q->elevator_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 elevator_change+0x1af/0x480 block/elevator.c:679 elv_iosched_store+0x504/0x630 block/elevator.c:826 queue_attr_store+0x207/0x2b0 block/blk-sysfs.c:906 kernfs_fop_write_iter+0x3a4/0x540 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&q->q_usage_counter(io)#66){++++}-{0:0}: blk_alloc_queue+0x544/0x690 block/blk-core.c:504 blk_mq_alloc_queue block/blk-mq.c:4431 [inline] __blk_mq_alloc_disk+0x194/0x390 block/blk-mq.c:4478 null_add_dev+0xe82/0x1d70 drivers/block/null_blk/main.c:2017 null_create_dev drivers/block/null_blk/main.c:2114 [inline] null_init+0x1e3/0x390 drivers/block/null_blk/main.c:2178 do_one_initcall+0x250/0x870 init/main.c:1362 do_initcall_level+0x10a/0x1a0 init/main.c:1424 do_initcalls+0x59/0xa0 init/main.c:1440 kernel_init_freeable+0x29d/0x3e0 init/main.c:1675 kernel_init+0x22/0x1d0 init/main.c:1565 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #2 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4375 [inline] fs_reclaim_acquire+0x71/0x100 mm/page_alloc.c:4389 might_alloc include/linux/sched/mm.h:316 [inline] slab_pre_alloc_hook mm/slub.c:4636 [inline] slab_alloc_node mm/slub.c:4974 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_noprof+0xbc/0x710 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] find_tree_dqentry+0x5c/0x1090 fs/quota/quota_tree.c:663 find_dqentry fs/quota/quota_tree.c:716 [inline] qtree_read_dquot+0x5ac/0x8a0 fs/quota/quota_tree.c:736 ocfs2_acquire_dquot+0x2d4/0xb70 fs/ocfs2/quota_global.c:852 dqget+0x725/0xbd0 fs/quota/dquot.c:1002 __dquot_initialize+0x3c8/0xd40 fs/quota/dquot.c:1462 ocfs2_get_init_inode+0x147/0x1c0 fs/ocfs2/namei.c:206 ocfs2_mknod+0x8af/0x21a0 fs/ocfs2/namei.c:315 ocfs2_create+0x195/0x460 fs/ocfs2/namei.c:678 lookup_open+0xee3/0x1970 fs/namei.c:4569 open_last_lookups fs/namei.c:4768 [inline] path_openat+0x710/0x20f0 fs/namei.c:5007 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1464 [inline] __se_sys_openat fs/open.c:1459 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1459 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&ocfs2_sysfile_lock_key[USER_QUOTA_SYSTEM_INODE]){+.+.}-{4:4}: down_write+0x91/0x200 kernel/locking/rwsem.c:1631 inode_lock include/linux/fs.h:1024 [inline] ocfs2_lock_global_qf+0x206/0x400 fs/ocfs2/quota_global.c:313 ocfs2_acquire_dquot+0x28c/0xb70 fs/ocfs2/quota_global.c:842 dqget+0x725/0xbd0 fs/quota/dquot.c:1002 __dquot_initialize+0x3c8/0xd40 fs/quota/dquot.c:1462 ocfs2_get_init_inode+0x147/0x1c0 fs/ocfs2/namei.c:206 ocfs2_mknod+0x8af/0x21a0 fs/ocfs2/namei.c:315 ocfs2_create+0x195/0x460 fs/ocfs2/namei.c:678 lookup_open+0xee3/0x1970 fs/namei.c:4569 open_last_lookups fs/namei.c:4768 [inline] path_openat+0x710/0x20f0 fs/namei.c:5007 do_file_open+0x23e/0x4a0 fs/namei.c:5039 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1464 [inline] __se_sys_openat fs/open.c:1459 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1459 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&dquot->dq_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 wait_on_dquot fs/quota/dquot.c:357 [inline] dqget+0x69d/0xbd0 fs/quota/dquot.c:997 dquot_transfer+0x2ac/0x660 fs/quota/dquot.c:2097 ext4_setattr+0x8a3/0x1df0 fs/ext4/inode.c:6062 notify_change+0xbba/0xea0 fs/attr.c:556 chown_common+0x41c/0x630 fs/open.c:825 vfs_fchown fs/open.c:890 [inline] ksys_fchown+0xe9/0x160 fs/open.c:902 __do_sys_fchown fs/open.c:907 [inline] __se_sys_fchown fs/open.c:905 [inline] __x64_sys_fchown+0x7a/0x90 fs/open.c:905 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &dquot->dq_lock --> mapping.invalidate_lock#2 --> &ei->xattr_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&ei->xattr_sem); lock(mapping.invalidate_lock#2); lock(&ei->xattr_sem); lock(&dquot->dq_lock); *** DEADLOCK *** locks held by syz.6.3297/16861: 3, last CPU#1: #0: ffff88807a788460 (sb_writers#4){++++}-{0:0}, at: mnt_want_write_file+0x60/0x200 fs/namespace.c:575 #1: ffff8880767027c0 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: inode_lock_killable include/linux/fs.h:1029 [inline] #1: ffff8880767027c0 (&type->i_mutex_dir_key#3){++++}-{4:4}, at: chown_common+0x313/0x630 fs/open.c:813 #2: ffff888076702500 (&ei->xattr_sem){++++}-{4:4}, at: ext4_setattr+0x891/0x1df0 fs/ext4/inode.c:6061 stack backtrace: CPU: 1 UID: 0 PID: 16861 Comm: syz.6.3297 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219 check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x197/0x15a0 kernel/locking/mutex.c:821 wait_on_dquot fs/quota/dquot.c:357 [inline] dqget+0x69d/0xbd0 fs/quota/dquot.c:997 dquot_transfer+0x2ac/0x660 fs/quota/dquot.c:2097 ext4_setattr+0x8a3/0x1df0 fs/ext4/inode.c:6062 notify_change+0xbba/0xea0 fs/attr.c:556 chown_common+0x41c/0x630 fs/open.c:825 vfs_fchown fs/open.c:890 [inline] ksys_fchown+0xe9/0x160 fs/open.c:902 __do_sys_fchown fs/open.c:907 [inline] __se_sys_fchown fs/open.c:905 [inline] __x64_sys_fchown+0x7a/0x90 fs/open.c:905 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f97ffd9f559 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:00007f9800cf4028 EFLAGS: 00000246 ORIG_RAX: 000000000000005d RAX: ffffffffffffffda RBX: 00007f9800025fa0 RCX: 00007f97ffd9f559 RDX: 000000000000ee01 RSI: 000000000000ee00 RDI: 0000000000000004 RBP: 00007f97ffe36b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9800026038 R14: 00007f9800025fa0 R15: 00007ffebd0b9088 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup