syzbot

ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
5.15.186-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.25/4421 is trying to acquire lock:
ffff8880782d4e28 (
&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x90/0x110 mm/memory.c:5356

but task is already holding lock:
ffff888072addbe0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_fiemap+0x2a2/0xc40 fs/ocfs2/extent_map.c:755

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}:
       down_read+0x44/0x2e0 kernel/locking/rwsem.c:1498
       ocfs2_read_virt_blocks+0x23f/0x8a0 fs/ocfs2/extent_map.c:976
       ocfs2_read_dir_block fs/ocfs2/dir.c:508 [inline]
       ocfs2_find_entry_el fs/ocfs2/dir.c:715 [inline]
       ocfs2_find_entry+0x3d1/0x1f90 fs/ocfs2/dir.c:1091
       ocfs2_find_files_on_disk+0xdb/0x2f0 fs/ocfs2/dir.c:1995
       ocfs2_lookup_ino_from_name+0x4f/0xf0 fs/ocfs2/dir.c:2017
       _ocfs2_get_system_file_inode fs/ocfs2/sysfile.c:136 [inline]
       ocfs2_get_system_file_inode+0x319/0x760 fs/ocfs2/sysfile.c:112
       ocfs2_init_global_system_inodes+0x316/0x650 fs/ocfs2/super.c:458
       ocfs2_initialize_super fs/ocfs2/super.c:2279 [inline]
       ocfs2_fill_super+0x3dbf/0x4d80 fs/ocfs2/super.c:995
       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

-> #3 (&osb->system_file_mutex){+.+.}-{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
       ocfs2_get_system_file_inode+0x1b5/0x760 fs/ocfs2/sysfile.c:101
       ocfs2_reserve_suballoc_bits+0x139/0x4350 fs/ocfs2/suballoc.c:776
       ocfs2_reserve_new_metadata_blocks+0x400/0x940 fs/ocfs2/suballoc.c:978
       ocfs2_reserve_new_metadata fs/ocfs2/suballoc.c:1021 [inline]
       ocfs2_lock_allocators+0x29b/0x5b0 fs/ocfs2/suballoc.c:2658
       ocfs2_extend_allocation+0x397/0x1760 fs/ocfs2/file.c:588
       ocfs2_allocate_unwritten_extents+0x2e6/0x7b0 fs/ocfs2/file.c:1499
       __ocfs2_change_file_space+0x81d/0xe20 fs/ocfs2/file.c:2026
       ocfs2_fallocate+0x1ee/0x240 fs/ocfs2/file.c:2141
       vfs_fallocate+0x587/0x6f0 fs/open.c:308
       ksys_fallocate fs/open.c:331 [inline]
       __do_sys_fallocate fs/open.c:339 [inline]
       __se_sys_fallocate fs/open.c:337 [inline]
       __x64_sys_fallocate+0xbd/0x100 fs/open.c:337
       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

-> #2 (&oi->ip_alloc_sem){++++}-{3:3}:
       down_write+0x38/0x60 kernel/locking/rwsem.c:1551
       ocfs2_page_mkwrite+0x2ce/0xad0 fs/ocfs2/mmap.c:142
       do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
       do_shared_fault mm/memory.c:4328 [inline]
       do_fault mm/memory.c:4396 [inline]
       handle_pte_fault mm/memory.c:4650 [inline]
       __handle_mm_fault mm/memory.c:4785 [inline]
       handle_mm_fault+0x1d4b/0x43c0 mm/memory.c:4883
       faultin_page mm/gup.c:976 [inline]
       __get_user_pages+0x93e/0x11c0 mm/gup.c:1197
       __get_user_pages_locked mm/gup.c:1442 [inline]
       get_user_pages_unlocked+0x400/0x6f0 mm/gup.c:2222
       __gup_longterm_unlocked mm/gup.c:2823 [inline]
       internal_get_user_pages_fast+0x1c9d/0x2080 mm/gup.c:2911
       iov_iter_get_pages+0x225/0x5b0 lib/iov_iter.c:1544
       dio_refill_pages fs/direct-io.c:173 [inline]
       dio_get_page fs/direct-io.c:217 [inline]
       do_direct_IO fs/direct-io.c:938 [inline]
       do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
       __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
       ocfs2_direct_IO+0x23e/0x2b0 fs/ocfs2/aops.c:2468
       generic_file_read_iter+0x2be/0x490 mm/filemap.c:2772
       ocfs2_file_read_iter+0x469/0xa20 fs/ocfs2/file.c:2592
       call_read_iter include/linux/fs.h:2166 [inline]
       new_sync_read fs/read_write.c:404 [inline]
       vfs_read+0x725/0xcf0 fs/read_write.c:485
       ksys_read+0x14d/0x250 fs/read_write.c:623
       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 (sb_pagefaults#2){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1811 [inline]
       sb_start_pagefault include/linux/fs.h:1910 [inline]
       ocfs2_page_mkwrite+0x18a/0xad0 fs/ocfs2/mmap.c:122
       do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
       do_shared_fault mm/memory.c:4328 [inline]
       do_fault mm/memory.c:4396 [inline]
       handle_pte_fault mm/memory.c:4650 [inline]
       __handle_mm_fault mm/memory.c:4785 [inline]
       handle_mm_fault+0x1d4b/0x43c0 mm/memory.c:4883
       faultin_page mm/gup.c:976 [inline]
       __get_user_pages+0x93e/0x11c0 mm/gup.c:1197
       __get_user_pages_locked mm/gup.c:1442 [inline]
       get_user_pages_unlocked+0x400/0x6f0 mm/gup.c:2222
       __gup_longterm_unlocked mm/gup.c:2823 [inline]
       internal_get_user_pages_fast+0x1c9d/0x2080 mm/gup.c:2911
       iov_iter_get_pages+0x225/0x5b0 lib/iov_iter.c:1544
       dio_refill_pages fs/direct-io.c:173 [inline]
       dio_get_page fs/direct-io.c:217 [inline]
       do_direct_IO fs/direct-io.c:938 [inline]
       do_blockdev_direct_IO fs/direct-io.c:1276 [inline]
       __blockdev_direct_IO+0x1060/0x3c90 fs/direct-io.c:1368
       ocfs2_direct_IO+0x23e/0x2b0 fs/ocfs2/aops.c:2468
       generic_file_read_iter+0x2be/0x490 mm/filemap.c:2772
       ocfs2_file_read_iter+0x469/0xa20 fs/ocfs2/file.c:2592
       call_read_iter include/linux/fs.h:2166 [inline]
       new_sync_read fs/read_write.c:404 [inline]
       vfs_read+0x725/0xcf0 fs/read_write.c:485
       ksys_read+0x14d/0x250 fs/read_write.c:623
       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 (&mm->mmap_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
       __might_fault+0xb3/0x110 mm/memory.c:5357
       _copy_to_user+0x29/0x130 lib/usercopy.c:35
       copy_to_user include/linux/uaccess.h:200 [inline]
       fiemap_fill_next_extent+0x19d/0x360 fs/ioctl.c:144
       ocfs2_fiemap_inline fs/ocfs2/extent_map.c:725 [inline]
       ocfs2_fiemap+0x999/0xc40 fs/ocfs2/extent_map.c:762
       ioctl_fiemap fs/ioctl.c:219 [inline]
       do_vfs_ioctl+0x1464/0x1de0 fs/ioctl.c:814
       __do_sys_ioctl fs/ioctl.c:872 [inline]
       __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860
       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:
  &mm->mmap_lock --> &osb->system_file_mutex --> &ocfs2_file_ip_alloc_sem_key

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_file_ip_alloc_sem_key);
                               lock(&osb->system_file_mutex);
                               lock(&ocfs2_file_ip_alloc_sem_key);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

1 lock held by syz.0.25/4421:
 #0: ffff888072addbe0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_fiemap+0x2a2/0xc40 fs/ocfs2/extent_map.c:755

stack backtrace:
CPU: 1 PID: 4421 Comm: syz.0.25 Not tainted 5.15.186-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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
 __might_fault+0xb3/0x110 mm/memory.c:5357
 _copy_to_user+0x29/0x130 lib/usercopy.c:35
 copy_to_user include/linux/uaccess.h:200 [inline]
 fiemap_fill_next_extent+0x19d/0x360 fs/ioctl.c:144
 ocfs2_fiemap_inline fs/ocfs2/extent_map.c:725 [inline]
 ocfs2_fiemap+0x999/0xc40 fs/ocfs2/extent_map.c:762
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x1464/0x1de0 fs/ioctl.c:814
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl+0x83/0x170 fs/ioctl.c:860
 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: 0033:0x7fdc8db3b929
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:00007fdc8b9a3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdc8dd62fa0 RCX: 00007fdc8db3b929
RDX: 0000200000000200 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007fdc8dbbdb39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdc8dd62fa0 R15: 00007ffcfe449948
 </TASK>