======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc7-next-20230621-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/26765 is trying to acquire lock:
ffff88803fc2cb90 (&sb->s_type->i_mutex_key
#42){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:771 [inline]
#42){+.+.}-{3:3}, at: f2fs_file_mmap+0x154/0x290 fs/f2fs/file.c:527

but task is already holding lock:
ffff888015f6b120 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:110 [inline]
ffff888015f6b120 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x158/0x3b0 mm/util.c:541

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_lock){++++}-{3:3}:
       __might_fault mm/memory.c:5717 [inline]
       __might_fault+0x115/0x190 mm/memory.c:5710
       _copy_to_user+0x2b/0xc0 lib/usercopy.c:36
       copy_to_user include/linux/uaccess.h:191 [inline]
       fiemap_fill_next_extent+0x217/0x370 fs/ioctl.c:144
       f2fs_xattr_fiemap fs/f2fs/data.c:1922 [inline]
       f2fs_fiemap+0x1375/0x1670 fs/f2fs/data.c:2010
       ioctl_fiemap fs/ioctl.c:219 [inline]
       do_vfs_ioctl+0x478/0x16c0 fs/ioctl.c:810
       __do_sys_ioctl fs/ioctl.c:868 [inline]
       __se_sys_ioctl fs/ioctl.c:856 [inline]
       __x64_sys_ioctl+0x10c/0x210 fs/ioctl.c:856
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&sb->s_type->i_mutex_key#42){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3142 [inline]
       check_prevs_add kernel/locking/lockdep.c:3261 [inline]
       validate_chain kernel/locking/lockdep.c:3876 [inline]
       __lock_acquire+0x2e9d/0x5e20 kernel/locking/lockdep.c:5144
       lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5761
       down_write+0x92/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:771 [inline]
       f2fs_file_mmap+0x154/0x290 fs/f2fs/file.c:527
       call_mmap include/linux/fs.h:1876 [inline]
       mmap_region+0x6cf/0x2570 mm/mmap.c:2669
       do_mmap+0x850/0xee0 mm/mmap.c:1373
       vm_mmap_pgoff+0x1a2/0x3b0 mm/util.c:543
       ksys_mmap_pgoff+0x42b/0x5b0 mm/mmap.c:1419
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_lock);
                               lock(&sb->s_type->i_mutex_key#42);
                               lock(&mm->mmap_lock);
  lock(&sb->s_type->i_mutex_key#42);

 *** DEADLOCK ***

1 lock held by syz-executor.2/26765:
 #0: ffff888015f6b120 (&mm->mmap_lock
){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:110 [inline]
){++++}-{3:3}, at: vm_mmap_pgoff+0x158/0x3b0 mm/util.c:541

stack backtrace:
CPU: 1 PID: 26765 Comm: syz-executor.2 Not tainted 6.4.0-rc7-next-20230621-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 check_noncircular+0x2df/0x3b0 kernel/locking/lockdep.c:2195
 check_prev_add kernel/locking/lockdep.c:3142 [inline]
 check_prevs_add kernel/locking/lockdep.c:3261 [inline]
 validate_chain kernel/locking/lockdep.c:3876 [inline]
 __lock_acquire+0x2e9d/0x5e20 kernel/locking/lockdep.c:5144
 lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5761
 down_write+0x92/0x200 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:771 [inline]
 f2fs_file_mmap+0x154/0x290 fs/f2fs/file.c:527
 call_mmap include/linux/fs.h:1876 [inline]
 mmap_region+0x6cf/0x2570 mm/mmap.c:2669
 do_mmap+0x850/0xee0 mm/mmap.c:1373
 vm_mmap_pgoff+0x1a2/0x3b0 mm/util.c:543
 ksys_mmap_pgoff+0x42b/0x5b0 mm/mmap.c:1419
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1d8d08c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1d8de14168 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f1d8d1ac050 RCX: 00007f1d8d08c389
RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000
RBP: 00007f1d8d0d7493 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffec88ddaaf R14: 00007f1d8de14300 R15: 0000000000022000
 </TASK>