syzbot

EXT4-fs (loop2): 1 truncate cleaned up
======================================================
WARNING: possible circular locking dependency detected
6.3.0-rc2-syzkaller-00235-g8d3c682a5e3d #0 Not tainted
------------------------------------------------------
syz-executor.2/10725 is trying to acquire lock:
ffff8880747a9810 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff8880747a9810 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}, at: ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:474

but task is already holding lock:
ffff888087418c90 (&ei->i_data_sem){++++}-{3:3}, at: ext4_setattr+0x14d4/0x1bc0 fs/ext4/inode.c:5588

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&ei->i_data_sem){++++}-{3:3}:
       lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1573
       ext4_update_i_disksize fs/ext4/ext4.h:3384 [inline]
       ext4_xattr_inode_write fs/ext4/xattr.c:1463 [inline]
       ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1612 [inline]
       ext4_xattr_set_entry+0x312d/0x3bf0 fs/ext4/xattr.c:1737
       ext4_xattr_ibody_set+0x121/0x330 fs/ext4/xattr.c:2289
       ext4_xattr_set_handle+0xb9a/0x15c0 fs/ext4/xattr.c:2446
       ext4_xattr_set+0x241/0x3d0 fs/ext4/xattr.c:2560
       __vfs_setxattr+0x460/0x4a0 fs/xattr.c:203
       __vfs_setxattr_noperm+0x12e/0x5e0 fs/xattr.c:237
       vfs_setxattr+0x221/0x420 fs/xattr.c:324
       do_setxattr fs/xattr.c:609 [inline]
       setxattr+0x25d/0x2f0 fs/xattr.c:632
       path_setxattr+0x1c0/0x2a0 fs/xattr.c:651
       __do_sys_setxattr fs/xattr.c:667 [inline]
       __se_sys_setxattr fs/xattr.c:663 [inline]
       __x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:663
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&ea_inode->i_rwsem#7/1){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3098 [inline]
       check_prevs_add kernel/locking/lockdep.c:3217 [inline]
       validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832
       __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
       lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:474
       ext4_xattr_inode_get+0x164/0x430 fs/ext4/xattr.c:551
       ext4_xattr_move_to_block fs/ext4/xattr.c:2641 [inline]
       ext4_xattr_make_inode_space fs/ext4/xattr.c:2743 [inline]
       ext4_expand_extra_isize_ea+0xf28/0x1d10 fs/ext4/xattr.c:2835
       __ext4_expand_extra_isize+0x2f7/0x3d0 fs/ext4/inode.c:5960
       ext4_try_to_expand_extra_isize fs/ext4/inode.c:6003 [inline]
       __ext4_mark_inode_dirty+0x53e/0x870 fs/ext4/inode.c:6081
       ext4_setattr+0x1567/0x1bc0 fs/ext4/inode.c:5591
       notify_change+0xc8b/0xf40 fs/attr.c:482
       do_truncate+0x220/0x300 fs/open.c:66
       handle_truncate fs/namei.c:3219 [inline]
       do_open fs/namei.c:3564 [inline]
       path_openat+0x294e/0x3170 fs/namei.c:3715
       do_filp_open+0x234/0x490 fs/namei.c:3742
       do_sys_openat2+0x13f/0x500 fs/open.c:1348
       do_sys_open fs/open.c:1364 [inline]
       __do_sys_openat fs/open.c:1380 [inline]
       __se_sys_openat fs/open.c:1375 [inline]
       __x64_sys_openat+0x247/0x290 fs/open.c:1375
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 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(&ei->i_data_sem);
                               lock(&ea_inode->i_rwsem#7/1);
                               lock(&ei->i_data_sem);
  lock(&ea_inode->i_rwsem#7/1);

 *** DEADLOCK ***

5 locks held by syz-executor.2/10725:
 #0: ffff888020a60460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:394
 #1: ffff888087418e08 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888087418e08 (&sb->s_type->i_mutex_key#7){++++}-{3:3}, at: do_truncate+0x20c/0x300 fs/open.c:64
 #2: ffff888087418fa8 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock include/linux/fs.h:803 [inline]
 #2: ffff888087418fa8 (mapping.invalidate_lock){++++}-{3:3}, at: ext4_setattr+0xf31/0x1bc0 fs/ext4/inode.c:5548
 #3: ffff888087418c90 (&ei->i_data_sem){++++}-{3:3}, at: ext4_setattr+0x14d4/0x1bc0 fs/ext4/inode.c:5588
 #4: ffff888087418ad0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_trylock_xattr fs/ext4/xattr.h:162 [inline]
 #4: ffff888087418ad0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_try_to_expand_extra_isize fs/ext4/inode.c:6000 [inline]
 #4: ffff888087418ad0 (&ei->xattr_sem){++++}-{3:3}, at: __ext4_mark_inode_dirty+0x4a5/0x870 fs/ext4/inode.c:6081

stack backtrace:
CPU: 1 PID: 10725 Comm: syz-executor.2 Not tainted 6.3.0-rc2-syzkaller-00235-g8d3c682a5e3d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3098 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3832
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1e1/0x520 kernel/locking/lockdep.c:5669
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 ext4_xattr_inode_iget+0x4a3/0x5e0 fs/ext4/xattr.c:474
 ext4_xattr_inode_get+0x164/0x430 fs/ext4/xattr.c:551
 ext4_xattr_move_to_block fs/ext4/xattr.c:2641 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2743 [inline]
 ext4_expand_extra_isize_ea+0xf28/0x1d10 fs/ext4/xattr.c:2835
 __ext4_expand_extra_isize+0x2f7/0x3d0 fs/ext4/inode.c:5960
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6003 [inline]
 __ext4_mark_inode_dirty+0x53e/0x870 fs/ext4/inode.c:6081
 ext4_setattr+0x1567/0x1bc0 fs/ext4/inode.c:5591
 notify_change+0xc8b/0xf40 fs/attr.c:482
 do_truncate+0x220/0x300 fs/open.c:66
 handle_truncate fs/namei.c:3219 [inline]
 do_open fs/namei.c:3564 [inline]
 path_openat+0x294e/0x3170 fs/namei.c:3715
 do_filp_open+0x234/0x490 fs/namei.c:3742
 do_sys_openat2+0x13f/0x500 fs/open.c:1348
 do_sys_open fs/open.c:1364 [inline]
 __do_sys_openat fs/open.c:1380 [inline]
 __se_sys_openat fs/open.c:1375 [inline]
 __x64_sys_openat+0x247/0x290 fs/open.c:1375
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff5eec8c0f9
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:00007ff5ef9a5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff5eedabf80 RCX: 00007ff5eec8c0f9
RDX: 0000000000105a41 RSI: 0000000020000140 RDI: ffffffffffffff9c
RBP: 00007ff5eece7b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000024 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc3108fd2f R14: 00007ff5ef9a5300 R15: 0000000000022000
 </TASK>