linux-stable.git/fs/dlm/lockspace.c, branch linux-6.1.y

dlm: prevent NPD when writing a positive value to event_done

2026-07-04T11:41:29+00:00

commit 8e2bad543eca5c25cd02cbc63d72557934d45f13 upstream.

do_uevent returns the value written to event_done. In case it is a
positive value, new_lockspace would undo all the work, and lockspace
would not be set. __dlm_new_lockspace, however, would treat that
positive value as a success due to commit 8511a2728ab8 ("dlm: fix use
count with multiple joins").

Down the line, device_create_lockspace would pass that NULL lockspace to
dlm_find_lockspace_local, leading to a NULL pointer dereference.

Treating such positive values as successes prevents the problem. Given
this has been broken for so long, this is unlikely to break userspace
expectations.

Fixes: 8511a2728ab8 ("dlm: fix use count with multiple joins")
Signed-off-by: Thadeu Lima de Souza Cascardo 
Signed-off-by: David Teigland 
Signed-off-by: Nazar Kalashnikov 
Signed-off-by: Greg Kroah-Hartman

dlm: check for defined force value in dlm_lockspace_release

2025-10-29T13:04:36+00:00

[ Upstream commit 6af515c9f3ccec3eb8a262ca86bef2c499d07951 ]

Force values over 3 are undefined, so don't treat them as 3.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Signed-off-by: Sasha Levin

fs: dlm: revert check required context while close

2023-07-23T11:49:34+00:00

commit c6b6d6dcc7f32767d57740e0552337c8de40610b upstream.

This patch reverts commit 2c3fa6ae4d52 ("dlm: check required context
while close"). The function dlm_midcomms_close(), which will call later
dlm_lowcomms_close(), is called when the cluster manager tells the node
got fenced which means on midcomms/lowcomms layer to disconnect the node
from the cluster communication. The node can rejoin the cluster later.
This patch was ensuring no new message were able to be triggered when we
are in the close() function context. This was done by checking if the
lockspace has been stopped. However there is a missing check that we
only need to check specific lockspaces where the fenced node is member
of. This is currently complicated because there is no way to easily
check if a node is part of a specific lockspace without stopping the
recovery. For now we just revert this commit as it is just a check to
finding possible leaks of stopping lockspaces before close() is called.

Cc: stable@vger.kernel.org
Fixes: 2c3fa6ae4d52 ("dlm: check required context while close")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Signed-off-by: Greg Kroah-Hartman

fs: dlm: start midcomms before scand

2023-03-17T07:50:18+00:00

[ Upstream commit aad633dc0cf90093998b1ae0ba9f19b5f1dab644 ]

The scand kthread can send dlm messages out, especially dlm remove
messages to free memory for unused rsb on other nodes. To send out dlm
messages, midcomms must be initialized. This patch moves the midcomms
start before scand is started.

Cc: stable@vger.kernel.org
Fixes: e7fd41792fc0 ("[DLM] The core of the DLM for GFS2/CLVM")
Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Signed-off-by: Sasha Levin

fs: dlm: add midcomms init/start functions

2023-03-17T07:50:18+00:00

[ Upstream commit 8b0188b0d60b6f6183b48380bac49fe080c5ded9 ]

This patch introduces leftovers of init, start, stop and exit
functionality. The dlm application layer should always call the midcomms
layer which getting aware of such event and redirect it to the lowcomms
layer. Some functionality which is currently handled inside the start
functionality of midcomms and lowcomms should be handled in the init
functionality as it only need to be initialized once when dlm is loaded.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Stable-dep-of: aad633dc0cf9 ("fs: dlm: start midcomms before scand")
Signed-off-by: Sasha Levin

fs: dlm: fix log of lowcomms vs midcomms

2023-03-17T07:50:17+00:00

[ Upstream commit 3e54c9e80e68b765d8877023d93f1eea1b9d1c54 ]

This patch will fix a small issue when printing out that
dlm_midcomms_start() failed to start and it was printing out that the
dlm subcomponent lowcomms was failed but lowcomms is behind the midcomms
layer.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland 
Stable-dep-of: aad633dc0cf9 ("fs: dlm: start midcomms before scand")
Signed-off-by: Sasha Levin

fs: dlm: remove DLM_LSFL_FS from uapi

2022-08-23T19:54:54+00:00

The DLM_LSFL_FS flag is set in lockspaces created directly
for a kernel user, as opposed to those lockspaces created
for user space applications.  The user space libdlm allowed
this flag to be set for lockspaces created from user space,
but then used by a kernel user.  No kernel user has ever
used this method, so remove the ability to do it.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

fs: dlm: change ls_clear_proc_locks to spinlock

2022-08-23T19:54:02+00:00

This patch changes the ls_clear_proc_locks to a spinlock because there
is no need to handle it as a mutex as there is no sleepable context when
ls_clear_proc_locks is held. This allows us to call those functionality
in non-sleepable contexts.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

fs: dlm: allow lockspaces have zero lvblen

2022-08-23T19:53:16+00:00

A dlm user may not use the DLM_LKF_VALBLK flag in the DLM API,
so a zero lvblen should be allowed as a lockspace parameter.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland

fs: dlm: don't use deprecated timeout features by default

2022-08-01T14:31:38+00:00

This patch will disable use of deprecated timeout features if
CONFIG_DLM_DEPRECATED_API is not set.  The deprecated features
will be removed in upcoming kernel release v6.2.

Signed-off-by: Alexander Aring 
Signed-off-by: David Teigland