syzbot

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.19/6001 is trying to acquire lock:
ffff88805955db90 (&oi->ip_alloc_sem){+.+.}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xb6/0x360 fs/ocfs2/refcounttree.c:932

but task is already holding lock:
ffff88805955dc18 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xa4/0x360 fs/ocfs2/refcounttree.c:931

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_xattr_sem){++++}-{4:4}:
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1631
       ocfs2_xattr_set_handle+0x3f7/0x820 fs/ocfs2/xattr.c:3545
       ocfs2_init_security_set+0xbd/0xe0 fs/ocfs2/xattr.c:7365
       ocfs2_mknod+0x16c8/0x2240 fs/ocfs2/namei.c:423
       ocfs2_create+0x195/0x460 fs/ocfs2/namei.c:677
       lookup_open fs/namei.c:4508 [inline]
       open_last_lookups fs/namei.c:4608 [inline]
       path_openat+0x1344/0x3850 fs/namei.c:4856
       do_file_open+0x23e/0x4a0 fs/namei.c:4888
       do_sys_openat2+0x115/0x200 fs/open.c:1368
       do_sys_open fs/open.c:1374 [inline]
       __do_sys_openat fs/open.c:1390 [inline]
       __se_sys_openat fs/open.c:1385 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1385
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&journal->j_trans_barrier){.+.+}-{4:4}:
       down_read+0x97/0x200 kernel/locking/rwsem.c:1574
       ocfs2_start_trans+0x3ac/0x700 fs/ocfs2/journal.c:369
       ocfs2_block_group_alloc fs/ocfs2/suballoc.c:801 [inline]
       ocfs2_reserve_suballoc_bits+0x7b7/0x4850 fs/ocfs2/suballoc.c:950
       ocfs2_reserve_new_metadata_blocks+0x415/0x9a0 fs/ocfs2/suballoc.c:1100
       ocfs2_mknod+0x10e1/0x2240 fs/ocfs2/namei.c:351
       ocfs2_create+0x195/0x460 fs/ocfs2/namei.c:677
       lookup_open fs/namei.c:4508 [inline]
       open_last_lookups fs/namei.c:4608 [inline]
       path_openat+0x1344/0x3850 fs/namei.c:4856
       do_file_open+0x23e/0x4a0 fs/namei.c:4888
       do_sys_openat2+0x115/0x200 fs/open.c:1368
       do_sys_open fs/open.c:1374 [inline]
       __do_sys_openat fs/open.c:1390 [inline]
       __se_sys_openat fs/open.c:1385 [inline]
       __x64_sys_openat+0x138/0x170 fs/open.c:1385
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal#2){.+.+}-{0:0}:
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs/super.h:19 [inline]
       sb_start_intwrite include/linux/fs/super.h:177 [inline]
       ocfs2_start_trans+0x2ac/0x700 fs/ocfs2/journal.c:367
       ocfs2_orphan_for_truncate fs/ocfs2/file.c:397 [inline]
       ocfs2_truncate_file+0x634/0x14b0 fs/ocfs2/file.c:506
       ocfs2_setattr+0x1641/0x1d10 fs/ocfs2/file.c:1224
       notify_change+0xbb8/0xec0 fs/attr.c:556
       do_truncate+0x1c2/0x250 fs/open.c:68
       handle_truncate fs/namei.c:4305 [inline]
       do_open fs/namei.c:4704 [inline]
       path_openat+0x3009/0x3850 fs/namei.c:4859
       do_file_open+0x23e/0x4a0 fs/namei.c:4888
       do_sys_openat2+0x115/0x200 fs/open.c:1368
       do_sys_open fs/open.c:1374 [inline]
       __do_sys_open fs/open.c:1382 [inline]
       __se_sys_open fs/open.c:1378 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1378
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&oi->ip_alloc_sem){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5237
       lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1631
       ocfs2_try_remove_refcount_tree+0xb6/0x360 fs/ocfs2/refcounttree.c:932
       ocfs2_truncate_file+0xe90/0x14b0 fs/ocfs2/file.c:527
       ocfs2_setattr+0x1641/0x1d10 fs/ocfs2/file.c:1224
       notify_change+0xbb8/0xec0 fs/attr.c:556
       do_truncate+0x1c2/0x250 fs/open.c:68
       handle_truncate fs/namei.c:4305 [inline]
       do_open fs/namei.c:4704 [inline]
       path_openat+0x3009/0x3850 fs/namei.c:4859
       do_file_open+0x23e/0x4a0 fs/namei.c:4888
       do_sys_openat2+0x115/0x200 fs/open.c:1368
       do_sys_open fs/open.c:1374 [inline]
       __do_sys_open fs/open.c:1382 [inline]
       __se_sys_open fs/open.c:1378 [inline]
       __x64_sys_open+0x11e/0x150 fs/open.c:1378
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &oi->ip_alloc_sem --> &journal->j_trans_barrier --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(&journal->j_trans_barrier);
                               lock(&oi->ip_xattr_sem);
  lock(&oi->ip_alloc_sem);

 *** DEADLOCK ***

3 locks held by syz.2.19/6001:
 #0: ffff88805a786500 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
 #1: ffff88805955df40 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:1029 [inline]
 #1: ffff88805955df40 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: do_truncate+0x18f/0x250 fs/open.c:63
 #2: ffff88805955dc18 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_try_remove_refcount_tree+0xa4/0x360 fs/ocfs2/refcounttree.c:931

stack backtrace:
CPU: 0 UID: 0 PID: 6001 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x1520/0x2ce0 kernel/locking/lockdep.c:5237
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1631
 ocfs2_try_remove_refcount_tree+0xb6/0x360 fs/ocfs2/refcounttree.c:932
 ocfs2_truncate_file+0xe90/0x14b0 fs/ocfs2/file.c:527
 ocfs2_setattr+0x1641/0x1d10 fs/ocfs2/file.c:1224
 notify_change+0xbb8/0xec0 fs/attr.c:556
 do_truncate+0x1c2/0x250 fs/open.c:68
 handle_truncate fs/namei.c:4305 [inline]
 do_open fs/namei.c:4704 [inline]
 path_openat+0x3009/0x3850 fs/namei.c:4859
 do_file_open+0x23e/0x4a0 fs/namei.c:4888
 do_sys_openat2+0x115/0x200 fs/open.c:1368
 do_sys_open fs/open.c:1374 [inline]
 __do_sys_open fs/open.c:1382 [inline]
 __se_sys_open fs/open.c:1378 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1378
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb1c649ce59
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:00007fb1c5afe028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fb1c6715fa0 RCX: 00007fb1c649ce59
RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000300
RBP: 00007fb1c6532e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb1c6716038 R14: 00007fb1c6715fa0 R15: 00007ffe98b6c998
 </TASK>