PF_CAN: dropped non conform CAN skbuff: dev type 280, len 65487
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.0.984/10663 is trying to acquire lock:
ffff88811bd006e8 (&oi->ip_xattr_sem){++++}-{4:4}, at: ocfs2_init_acl+0x2fd/0x7e0

but task is already holding lock:
ffff8881109270e0 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3ab/0x700

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&journal->j_trans_barrier){.+.+}-{4:4}:
       down_read+0x47/0x2e0
       ocfs2_start_trans+0x3ab/0x700
       ocfs2_mknod+0x1181/0x2260
       ocfs2_mkdir+0x181/0x460
       vfs_mkdir+0x413/0x630
       filename_mkdirat+0x285/0x510
       __se_sys_mkdirat+0x35/0x150
       do_syscall_64+0x15f/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (sb_internal#4){.+.+}-{0:0}:
       ocfs2_start_trans+0x2ac/0x700
       ocfs2_setattr+0xcc6/0x1ca0
       notify_change+0xc1a/0xf40
       chown_common+0x466/0x6b0
       do_fchownat+0x14c/0x250
       __x64_sys_lchown+0x85/0xa0
       do_syscall_64+0x15f/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}:
       down_write+0x96/0x200
       ocfs2_try_remove_refcount_tree+0xb6/0x340
       ocfs2_truncate_file+0xdf3/0x14e0
       ocfs2_setattr+0x15e5/0x1ca0
       notify_change+0xc1a/0xf40
       do_truncate+0x1c2/0x250
       path_openat+0x2f89/0x3860
       do_file_open+0x23e/0x4a0
       do_sys_openat2+0x113/0x200
       __x64_sys_open+0x11e/0x150
       do_syscall_64+0x15f/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&oi->ip_xattr_sem){++++}-{4:4}:
       __lock_acquire+0x15a5/0x2cf0
       lock_acquire+0x106/0x350
       down_read+0x47/0x2e0
       ocfs2_init_acl+0x2fd/0x7e0
       ocfs2_mknod+0x1679/0x2260
       ocfs2_create+0x195/0x460
       path_openat+0x1395/0x3860
       do_file_open+0x23e/0x4a0
       do_sys_openat2+0x113/0x200
       __x64_sys_openat+0x138/0x170
       do_syscall_64+0x15f/0xf80
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &oi->ip_xattr_sem --> sb_internal#4 --> &journal->j_trans_barrier

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(&journal->j_trans_barrier);
                               lock(sb_internal#4);
                               lock(&journal->j_trans_barrier);
  rlock(&oi->ip_xattr_sem);

 *** DEADLOCK ***

8 locks held by syz.0.984/10663:
 #0: ffff88811573e410 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff88811bd009a0 (&type->i_mutex_dir_key#11){++++}-{4:4}, at: path_openat+0xb4c/0x3860
 #2: ffff8881a68997a0 (&ocfs2_sysfile_lock_key[INODE_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4840
 #3: ffff888117a941a0 (&ocfs2_sysfile_lock_key[EXTENT_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4840
 #4: ffff888117a95da0 (&ocfs2_sysfile_lock_key[GLOBAL_BITMAP_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_suballoc_bits+0x16d/0x4840
 #5: ffff88811573e600 (sb_internal#4){.+.+}-{0:0}, at: ocfs2_mknod+0x1181/0x2260
 #6: ffff8881109270e0 (&journal->j_trans_barrier){.+.+}-{4:4}, at: ocfs2_start_trans+0x3ab/0x700
 #7: ffff88810378a938 (jbd2_handle#2){.+.+}-{0:0}, at: start_this_handle+0x2054/0x2290

stack backtrace:
CPU: 1 UID: 0 PID: 10663 Comm: syz.0.984 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e1/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x15a5/0x2cf0
 lock_acquire+0x106/0x350
 down_read+0x47/0x2e0
 ocfs2_init_acl+0x2fd/0x7e0
 ocfs2_mknod+0x1679/0x2260
 ocfs2_create+0x195/0x460
 path_openat+0x1395/0x3860
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f162359cdd9
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:00007f162443a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1623815fa0 RCX: 00007f162359cdd9
RDX: 0000000000105042 RSI: 0000200000000340 RDI: ffffffffffffff9c
RBP: 00007f1623632d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1623816038 R14: 00007f1623815fa0 R15: 00007ffcfb197e68
 </TASK>
