ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock

When user_dlm_destroy_lock failed, it didn't clean up the flags it set
before exit. For USER_LOCK_IN_TEARDOWN, if this function fails because of
lock is still in used, next time when unlink invokes this function, it
will return succeed, and then unlink will remove inode and dentry if lock
is not in used(file closed), but the dlm lock is still linked in dlm lock
resource, then when bast come in, it will trigger a panic due to
user-after-free. See the following panic call trace. To fix this,
USER_LOCK_IN_TEARDOWN should be reverted if fail. And also error should
be returned if USER_LOCK_IN_TEARDOWN is set to let user know that unlink
fail.

For the case of ocfs2_dlm_unlock failure, besides USER_LOCK_IN_TEARDOWN,
USER_LOCK_BUSY is also required to be cleared. Even though spin lock is
released in between, but USER_LOCK_IN_TEARDOWN is still set, for
USER_LOCK_BUSY, if before every place that waits on this flag,
USER_LOCK_IN_TEARDOWN is checked to bail out, that will make sure no flow
waits on the busy flag set by user_dlm_destroy_lock(), then we can
simplely revert USER_LOCK_BUSY when ocfs2_dlm_unlock fails. Fix
user_dlm_cluster_lock() which is the only function not following this.

[ 941.336392] (python,26174,16):dlmfs_unlink:562 ERROR: unlink
004fb0000060000b5a90b8c847b72e1, error -16 from destroy
[ 989.757536] ------------[ cut here ]------------
[ 989.757709] kernel BUG at fs/ocfs2/dlmfs/userdlm.c:173!
[ 989.757876] invalid opcode: 0000 [#1] SMP
[ 989.758027] Modules linked in: ksplice_2zhuk2jr_ib_ipoib_new(O)
ksplice_2zhuk2jr(O) mptctl mptbase xen_netback xen_blkback xen_gntalloc
xen_gntdev xen_evtchn cdc_ether usbnet mii ocfs2 jbd2 rpcsec_gss_krb5
auth_rpcgss nfsv4 nfsv3 nfs_acl nfs fscache lockd grace ocfs2_dlmfs
ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs bnx2fc
fcoe libfcoe libfc scsi_transport_fc sunrpc ipmi_devintf bridge stp llc
rds_rdma rds bonding ib_sdp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad
rdma_cm ib_cm iw_cm falcon_lsm_serviceable(PE) falcon_nf_netcontain(PE)
mlx4_vnic falcon_kal(E) falcon_lsm_pinned_13402(E) mlx4_ib ib_sa ib_mad
ib_core ib_addr xenfs xen_privcmd dm_multipath iTCO_wdt iTCO_vendor_support
pcspkr sb_edac edac_core i2c_i801 lpc_ich mfd_core ipmi_ssif i2c_core ipmi_si
ipmi_msghandler
[ 989.760686] ioatdma sg ext3 jbd mbcache sd_mod ahci libahci ixgbe dca ptp
pps_core vxlan udp_tunnel ip6_udp_tunnel megaraid_sas mlx4_core crc32c_intel
be2iscsi bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi ipv6 cxgb3 mdio
libiscsi_tcp qla4xxx iscsi_boot_sysfs libiscsi scsi_transport_iscsi wmi
dm_mirror dm_region_hash dm_log dm_mod [last unloaded:
ksplice_2zhuk2jr_ib_ipoib_old]
[ 989.761987] CPU: 10 PID: 19102 Comm: dlm_thread Tainted: P OE
4.1.12-124.57.1.el6uek.x86_64 #2
[ 989.762290] Hardware name: Oracle Corporation ORACLE SERVER
X5-2/ASM,MOTHERBOARD,1U, BIOS 30350100 06/17/2021
[ 989.762599] task: ffff880178af6200 ti: ffff88017f7c8000 task.ti:
ffff88017f7c8000
[ 989.762848] RIP: e030:[<ffffffffc07d4316>] [<ffffffffc07d4316>]
__user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs]
[ 989.763185] RSP: e02b:ffff88017f7cbcb8 EFLAGS: 00010246
[ 989.763353] RAX: 0000000000000000 RBX: ffff880174d48008 RCX:
0000000000000003
[ 989.763565] RDX: 0000000000120012 RSI: 0000000000000003 RDI:
ffff880174d48170
[ 989.763778] RBP: ffff88017f7cbcc8 R08: ffff88021f4293b0 R09:
0000000000000000
[ 989.763991] R10: ffff880179c8c000 R11: 0000000000000003 R12:
ffff880174d48008
[ 989.764204] R13: 0000000000000003 R14: ffff880179c8c000 R15:
ffff88021db7a000
[ 989.764422] FS: 0000000000000000(0000) GS:ffff880247480000(0000)
knlGS:ffff880247480000
[ 989.764685] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 989.764865] CR2: ffff8000007f6800 CR3: 0000000001ae0000 CR4:
0000000000042660
[ 989.765081] Stack:
[ 989.765167] 0000000000000003 ffff880174d48040 ffff88017f7cbd18
ffffffffc07d455f
[ 989.765442] ffff88017f7cbd88 ffffffff816fb639 ffff88017f7cbd38
ffff8800361b5600
[ 989.765717] ffff88021db7a000 ffff88021f429380 0000000000000003
ffffffffc0453020
[ 989.765991] Call Trace:
[ 989.766093] [<ffffffffc07d455f>] user_bast+0x5f/0xf0 [ocfs2_dlmfs]
[ 989.766287] [<ffffffff816fb639>] ? schedule_timeout+0x169/0x2d0
[ 989.766475] [<ffffffffc0453020>] ? o2dlm_lock_ast_wrapper+0x20/0x20
[ocfs2_stack_o2cb]
[ 989.766738] [<ffffffffc045303a>] o2dlm_blocking_ast_wrapper+0x1a/0x20
[ocfs2_stack_o2cb]
[ 989.767010] [<ffffffffc0864ec6>] dlm_do_local_bast+0x46/0xe0 [ocfs2_dlm]
[ 989.767217] [<ffffffffc084f5cc>] ? dlm_lockres_calc_usage+0x4c/0x60
[ocfs2_dlm]
[ 989.767466] [<ffffffffc08501f1>] dlm_thread+0xa31/0x1140 [ocfs2_dlm]
[ 989.767662] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.767834] [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[ 989.768006] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.768178] [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[ 989.768349] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.768521] [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[ 989.768693] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.768893] [<ffffffff816f78ce>] ? __schedule+0x23e/0x810
[ 989.769067] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.769241] [<ffffffff810ce4d0>] ? wait_woken+0x90/0x90
[ 989.769411] [<ffffffffc084f7c0>] ? dlm_kick_thread+0x80/0x80 [ocfs2_dlm]
[ 989.769617] [<ffffffff810a8bbb>] kthread+0xcb/0xf0
[ 989.769774] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.769945] [<ffffffff816f78da>] ? __schedule+0x24a/0x810
[ 989.770117] [<ffffffff810a8af0>] ? kthread_create_on_node+0x180/0x180
[ 989.770321] [<ffffffff816fdaa1>] ret_from_fork+0x61/0x90
[ 989.770492] [<ffffffff810a8af0>] ? kthread_create_on_node+0x180/0x180
[ 989.770689] Code: d0 00 00 00 f0 45 7d c0 bf 00 20 00 00 48 89 83 c0 00 00
00 48 89 83 c8 00 00 00 e8 55 c1 8c c0 83 4b 04 10 48 83 c4 08 5b 5d c3 <0f>
0b 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 41 54 53 48 83
[ 989.771892] RIP [<ffffffffc07d4316>]
__user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs]
[ 989.772174] RSP <ffff88017f7cbcb8>
[ 989.772704] ---[ end trace ebd1e38cebcc93a8 ]---
[ 989.772907] Kernel panic - not syncing: Fatal exception
[ 989.773173] Kernel Offset: disabled

Link: https://lkml.kernel.org/r/20220518235224.87100-2-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ocfs2: dlmfs: don't clear USER_LOCK_ATTACHED when destroying lock

The following function is the only place that checks USER_LOCK_ATTACHED.
This flag is set when lock request is granted through user_ast() and only
the following function will clear it.

Checking of this flag here is to make sure ocfs2_dlm_unlock is not issued
if this lock is never granted. For example, lock file is created and then
get removed, open file never happens.

Clearing the flag here is not necessary because this is the only function
that checks it, if another flow is executing user_dlm_destroy_lock(), it
will bail out at the beginning because of USER_LOCK_IN_TEARDOWN and never
check USER_LOCK_ATTACHED. Drop the clear, so we don't need take care of
it for the following error handling patch.

int user_dlm_destroy_lock(struct user_lock_res *lockres)
{
...

status = 0;
if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
spin_unlock(&lockres->l_lock);
goto bail;
}

lockres->l_flags &= ~USER_LOCK_ATTACHED;
lockres->l_flags |= USER_LOCK_BUSY;
spin_unlock(&lockres->l_lock);

status = ocfs2_dlm_unlock(conn, &lockres->l_lksb, DLM_LKF_VALBLK);
if (status) {
user_log_dlm_error("ocfs2_dlm_unlock", status, lockres);
goto bail;
}
...
}

V1 discussion with Joseph:
https://lore.kernel.org/all/7b620c53-0c45-da2c-829e-26195cbe7d4e@linux.alibaba.com/T/

Link: https://lkml.kernel.org/r/20220518235224.87100-1-junxiao.bi@oracle.com
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

treewide: remove editor modelines and cruft

The section "19) Editor modelines and other cruft" in
Documentation/process/coding-style.rst clearly says, "Do not include any
of these in source files."

I recently receive a patch to explicitly add a new one.

Let's do treewide cleanups, otherwise some people follow the existing code
and attempt to upstream their favoriate editor setups.

It is even nicer if scripts/checkpatch.pl can check it.

If we like to impose coding style in an editor-independent manner, I think
editorconfig (patch [1]) is a saner solution.

[1] https://lore.kernel.org/lkml/20200703073143.423557-1-danny@kdrag0n.dev/

Link: https://lkml.kernel.org/r/20210324054457.1477489-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org> [auxdisplay]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dlmfs: clean up dlmfs_file_{read,write}() a bit

The damn file is constant-sized - 64 bytes. IOW,
* i_size_read() is pointless
* so's dynamic allocation
* so's the 'size' argument of user_dlm_read_lvb()
* ... and so's open-coding simple_read_from_buffer(), while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ocfs2: make local header paths relative to C files

Gang He reports the failure of building fs/ocfs2/ as an external module
of the kernel installed on the system:

$ cd fs/ocfs2
$ make -C /lib/modules/`uname -r`/build M=`pwd` modules

If you want to make it work reliably, I'd recommend to remove ccflags-y
from the Makefiles, and to make header paths relative to the C files. I
think this is the correct usage of the #include "..." directive.

Link: http://lkml.kernel.org/r/20191227022950.14804-1-ghe@suse.com
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Gang He <ghe@suse.com>
Reported-by: Gang He <ghe@suse.com>
Reviewed-by: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 145

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 021110 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 84 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190524100844.756442981@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

qstr: constify instances in ocfs2

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ocfs2/userdlm: Add tracing in userdlm

Make use of the newly added BASTS masklog to trace ASTs and BASTs in userdlm.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>

ocfs2_dlmfs: Enable the use of user cluster stacks.

Unlike ocfs2, dlmfs has no permanent storage. It can't store off a
cluster stack it is supposed to be using. So it can't specify the stack
name in ocfs2_cluster_connect().

Instead, we create ocfs2_cluster_connect_agnostic(), which simply uses
the stack that is currently enabled. This is find for dlmfs, which will
rely on the stack initialization.

We add the "stackglue" capability to dlmfs's capability list. This lets
userspace know dlmfs can be used with all cluster stacks.

Signed-off-by: Joel Becker <joel.becker@oracle.com>

ocfs2_dlmfs: Use the stackglue.

Rather than directly using o2dlm, dlmfs can now use the stackglue. This
allows it to use userspace cluster stacks and fs/dlm. This commit
forces o2cb for now. A latter commit will bump the protocol version and
allow non-o2cb stacks.

This is one big sed, really. LKM_xxMODE becomes DLM_LOCK_xx. LKM_flag
becomes DLM_LKF_flag.

We also learn to check that the LVB is valid before reading it. Any DLM
can lose the contents of the LVB during a complicated recovery. userdlm
should be checking this. Now it does. dlmfs will return 0 from read(2)
if the LVB was invalid.

Signed-off-by: Joel Becker <joel.becker@oracle.com>

ocfs2_dlmfs: Move to its own directory

We're going to remove the tie between ocfs2_dlmfs and o2dlm.
ocfs2_dlmfs doesn't belong in the fs/ocfs2/dlm directory anymore. Here
we move it to fs/ocfs2/dlmfs.

Signed-off-by: Joel Becker <joel.becker@oracle.com>