kernel/git/stable/linux.git/fs/dlm/lock.c, branch linux-5.16.y

fs: dlm: filter user dlm messages for kernel locks

2022-01-27T11:02:12+00:00

[ Upstream commit 6c2e3bf68f3e5e5a647aa52be246d5f552d7496d ] This patch fixes the following crash by receiving a invalid message: [ 160.672220] ================================================================== [ 160.676206] BUG: KASAN: user-memory-access in dlm_user_add_ast+0xc3/0x370 [ 160.679659] Read of size 8 at addr 00000000deadbeef by task kworker/u32:13/319 [ 160.681447] [ 160.681824] CPU: 10 PID: 319 Comm: kworker/u32:13 Not tainted 5.14.0-rc2+ #399 [ 160.683472] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.14.0-1.module+el8.6.0+12648+6ede71a5 04/01/2014 [ 160.685574] Workqueue: dlm_recv process_recv_sockets [ 160.686721] Call Trace: [ 160.687310] dump_stack_lvl+0x56/0x6f [ 160.688169] ? dlm_user_add_ast+0xc3/0x370 [ 160.689116] kasan_report.cold.14+0x116/0x11b [ 160.690138] ? dlm_user_add_ast+0xc3/0x370 [ 160.690832] dlm_user_add_ast+0xc3/0x370 [ 160.691502] _receive_unlock_reply+0x103/0x170 [ 160.692241] _receive_message+0x11df/0x1ec0 [ 160.692926] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 160.693700] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 160.694427] ? lock_acquire+0x175/0x400 [ 160.695058] ? do_purge.isra.51+0x200/0x200 [ 160.695744] ? lock_acquired+0x360/0x5d0 [ 160.696400] ? lock_contended+0x6a0/0x6a0 [ 160.697055] ? lock_release+0x21d/0x5e0 [ 160.697686] ? lock_is_held_type+0xe0/0x110 [ 160.698352] ? lock_is_held_type+0xe0/0x110 [ 160.699026] ? ___might_sleep+0x1cc/0x1e0 [ 160.699698] ? dlm_wait_requestqueue+0x94/0x140 [ 160.700451] ? dlm_process_requestqueue+0x240/0x240 [ 160.701249] ? down_write_killable+0x2b0/0x2b0 [ 160.701988] ? do_raw_spin_unlock+0xa2/0x130 [ 160.702690] dlm_receive_buffer+0x1a5/0x210 [ 160.703385] dlm_process_incoming_buffer+0x726/0x9f0 [ 160.704210] receive_from_sock+0x1c0/0x3b0 [ 160.704886] ? dlm_tcp_shutdown+0x30/0x30 [ 160.705561] ? lock_acquire+0x175/0x400 [ 160.706197] ? rcu_read_lock_sched_held+0xa1/0xd0 [ 160.706941] ? rcu_read_lock_bh_held+0xb0/0xb0 [ 160.707681] process_recv_sockets+0x32/0x40 [ 160.708366] process_one_work+0x55e/0xad0 [ 160.709045] ? pwq_dec_nr_in_flight+0x110/0x110 [ 160.709820] worker_thread+0x65/0x5e0 [ 160.710423] ? process_one_work+0xad0/0xad0 [ 160.711087] kthread+0x1ed/0x220 [ 160.711628] ? set_kthread_struct+0x80/0x80 [ 160.712314] ret_from_fork+0x22/0x30 The issue is that we received a DLM message for a user lock but the destination lock is a kernel lock. Note that the address which is trying to derefence is 00000000deadbeef, which is in a kernel lock lkb->lkb_astparam, this field should never be derefenced by the DLM kernel stack. In case of a user lock lkb->lkb_astparam is lkb->lkb_ua (memory is shared by a union field). The struct lkb_ua will be handled by the DLM kernel stack but on a kernel lock it will contain invalid data and ends in most likely crashing the kernel. It can be reproduced with two cluster nodes. node 2: dlm_tool join test echo "862 fooobaar 1 2 1" > /sys/kernel/debug/dlm/test_locks echo "862 3 1" > /sys/kernel/debug/dlm/test_waiters node 1: dlm_tool join test python: foo = DLM(h_cmd=3, o_nextcmd=1, h_nodeid=1, h_lockspace=0x77222027, \ m_type=7, m_flags=0x1, m_remid=0x862, m_result=0xFFFEFFFE) newFile = open("/sys/kernel/debug/dlm/comms/2/rawmsg", "wb") newFile.write(bytes(foo)) Signed-off-by: Alexander Aring Signed-off-by: David Teigland Signed-off-by: Sasha Levin

fs: dlm: add union in dlm header for lockspace id

2021-05-25T14:22:20+00:00

This patch adds union inside the lockspace id to handle it also for another use case for a different dlm command. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: add more midcomms hooks

2021-05-25T14:22:20+00:00

This patch prepares hooks to redirect to the midcomms layer which will be used by the midcomms re-transmit handling. There exists the new concept of stateless buffers allocation and commits. This can be used to bypass the midcomms re-transmit handling. It is used by RCOM_STATUS and RCOM_NAMES messages, because they have their own ping-like re-transmit handling. As well these two messages will be used to determine the DLM version per node, because these two messages are per observation the first messages which are exchanged. Cluster manager events for node membership are added to add support for half-closed connections in cases that the peer connection get to an end of file but DLM still holds membership of the node. In this time DLM can still trigger new message which we should allow. After the cluster manager node removal event occurs it safe to close the connection. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

fs: dlm: use GFP_ZERO for page buffer

2021-03-09T14:56:42+00:00

This patch uses GFP_ZERO for allocate a page for the internal dlm sending buffer allocator instead of calling memset zero after every allocation. An already allocated space will never be reused again. Signed-off-by: Alexander Aring Signed-off-by: David Teigland

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193

2019-05-30T18:29:21+00:00

Based on 1 normalized pattern(s): this copyrighted material is made available to anyone wishing to use modify copy or redistribute it subject to the terms and conditions of the gnu general public license v 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 45 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Richard Fontana Reviewed-by: Allison Randal Reviewed-by: Steve Winslow Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de Signed-off-by: Greg Kroah-Hartman

dlm: memory leaks on error path in dlm_user_request()

2018-11-15T15:57:22+00:00

According to comment in dlm_user_request() ua should be freed in dlm_free_lkb() after successful attach to lkb. However ua is attached to lkb not in set_lock_args() but later, inside request_lock(). Fixes 597d0cae0f99 ("[DLM] dlm: user locks") Cc: stable@kernel.org # 2.6.19 Signed-off-by: Vasily Averin Signed-off-by: David Teigland

dlm: lost put_lkb on error path in receive_convert() and receive_unlock()

2018-11-15T15:57:22+00:00

Fixes 6d40c4a708e0 ("dlm: improve error and debug messages") Cc: stable@kernel.org # 3.5 Signed-off-by: Vasily Averin Signed-off-by: David Teigland

dlm: possible memory leak on error path in create_lkb()

2018-11-15T15:57:22+00:00

Fixes 3d6aa675fff9 ("dlm: keep lkbs in idr") Cc: stable@kernel.org # 3.1 Signed-off-by: Vasily Averin Signed-off-by: David Teigland

dlm: remove dlm_send_rcom_lookup_dump

2017-10-09T14:29:31+00:00

This function was only for debugging. It would be called in a condition that should not happen, and should probably have been removed from the final version of the original commit. Remove it because it does mutex lock under spin lock. Signed-off-by: David Teigland