syzbot

======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc5-syzkaller-00024-g5f63595ebd82 #0 Not tainted
------------------------------------------------------
syz-executor241/6969 is trying to acquire lock:
ffff88803114c090 (&sbi->lock
){+.+.}-{3:3}, at: reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27

but task is already holding lock:
ffff888017344da8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:110 [inline]
ffff888017344da8 (&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:5732 [inline]
       __might_fault+0x115/0x190 mm/memory.c:5725
       reiserfs_ioctl+0x1d2/0x330 fs/reiserfs/ioctl.c:96
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl fs/ioctl.c:856 [inline]
       __x64_sys_ioctl+0x197/0x210 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 (&sbi->lock
){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3113 [inline]
       check_prevs_add kernel/locking/lockdep.c:3232 [inline]
       validate_chain kernel/locking/lockdep.c:3847 [inline]
       __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088
       lock_acquire kernel/locking/lockdep.c:5705 [inline]
       lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747
       reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27
       reiserfs_dirty_inode+0xd2/0x260 fs/reiserfs/super.c:704
       __mark_inode_dirty+0x1e0/0xd60 fs/fs-writeback.c:2424
       generic_update_time fs/inode.c:1859 [inline]
       inode_update_time fs/inode.c:1872 [inline]
       touch_atime+0x687/0x740 fs/inode.c:1944
       file_accessed include/linux/fs.h:2198 [inline]
       generic_file_mmap+0x119/0x150 mm/filemap.c:3600
       call_mmap include/linux/fs.h:1873 [inline]
       mmap_region+0x694/0x28d0 mm/mmap.c:2652
       do_mmap+0x831/0xf60 mm/mmap.c:1394
       vm_mmap_pgoff+0x1a2/0x3b0 mm/util.c:543
       ksys_mmap_pgoff+0x41f/0x5a0 mm/mmap.c:1440
       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(&sbi->lock);
                               lock(&mm->mmap_lock);
  lock(&sbi->lock);

 *** DEADLOCK ***

2 locks held by syz-executor241/6969:
 #0: ffff888017344da8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:110 [inline]
 #0: ffff888017344da8 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x158/0x3b0 mm/util.c:541
 #1: ffff88802def2460 (sb_writers#10){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2198 [inline]
 #1: ffff88802def2460 (sb_writers#10){.+.+}-{0:0}, at: generic_file_mmap+0x119/0x150 mm/filemap.c:3600

stack backtrace:
CPU: 2 PID: 6969 Comm: syz-executor241 Not tainted 6.4.0-rc5-syzkaller-00024-g5f63595ebd82 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2188
 check_prev_add kernel/locking/lockdep.c:3113 [inline]
 check_prevs_add kernel/locking/lockdep.c:3232 [inline]
 validate_chain kernel/locking/lockdep.c:3847 [inline]
 __lock_acquire+0x2fcd/0x5f30 kernel/locking/lockdep.c:5088
 lock_acquire kernel/locking/lockdep.c:5705 [inline]
 lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747
 reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27
 reiserfs_dirty_inode+0xd2/0x260 fs/reiserfs/super.c:704
 __mark_inode_dirty+0x1e0/0xd60 fs/fs-writeback.c:2424
 generic_update_time fs/inode.c:1859 [inline]
 inode_update_time fs/inode.c:1872 [inline]
 touch_atime+0x687/0x740 fs/inode.c:1944
 file_accessed include/linux/fs.h:2198 [inline]
 generic_file_mmap+0x119/0x150 mm/filemap.c:3600
 call_mmap include/linux/fs.h:1873 [inline]
 mmap_region+0x694/0x28d0 mm/mmap.c:2652
 do_mmap+0x831/0xf60 mm/mmap.c:1394
 vm_mmap_pgoff+0x1a2/0x3b0 mm/util.c:543
 ksys_mmap_pgoff+0x41f/0x5a0 mm/mmap.c:1440
 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: 0033:0x7f31bb5b0a99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 15 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:00007f31bb55c2e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000020 RCX: 00007f31bb5b0a99
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007f31bb6367a8 R08: 0000000000000006 R09: 0000000000000000
R10: 0000000000028011 R11: 0000000000000246 R12: 00007f31bb6367a0
R13: 00007f31bb6031f8 R14: 7366726573696572 R15: 632e79726f6d656d
 </TASK>