treewide: const qualify ctl_tables where applicable

Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysc

treewide: const qualify ctl_tables where applicable

Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.

Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.

Created this by running an spatch followed by a sed command:
Spatch:
virtual patch

@
depends on !(file in "net")
disable optional_qualifier
@

identifier table_name != {
watchdog_hardlockup_sysctl,
iwcm_ctl_table,
ucma_ctl_table,
memory_allocation_profiling_sysctls,
loadpin_sysctl_table
};
@@

+ const
struct ctl_table table_name [] = { ... };

sed:
sed --in-place \
-e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
kernel/utsname_sysctl.c

Reviewed-by: Song Liu <[email protected]>
Acked-by: Steven Rostedt (Google) <[email protected]> # for kernel/trace/
Reviewed-by: Martin K. Petersen <[email protected]> # SCSI
Reviewed-by: Darrick J. Wong <[email protected]> # xfs
Acked-by: Jani Nikula <[email protected]>
Acked-by: Corey Minyard <[email protected]>
Acked-by: Wei Liu <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Reviewed-by: Bill O'Donnell <[email protected]>
Acked-by: Baoquan He <[email protected]>
Acked-by: Ashutosh Dixit <[email protected]>
Acked-by: Anna Schumaker <[email protected]>
Signed-off-by: Joel Granados <[email protected]>

show more ...

ipc: remove the now superfluous sentinel element from ctl_table array

This commit comes at the tail end of a greater effort to remove the empty
elements at the end of the ctl_table arrays (sentinels

ipc: remove the now superfluous sentinel element from ctl_table array

This commit comes at the tail end of a greater effort to remove the empty
elements at the end of the ctl_table arrays (sentinels) which will reduce
the overall build time size of the kernel and run time memory bloat by ~64
bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%[email protected]/)

Remove the sentinels from ipc_sysctls and mq_sysctls

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Joel Granados <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

sysctl: treewide: constify argument ctl_table_root::permissions(table)

The permissions callback should not modify the ctl_table. Enforce this
expectation via the typesystem. This is a step to put "s

sysctl: treewide: constify argument ctl_table_root::permissions(table)

The permissions callback should not modify the ctl_table. Enforce this
expectation via the typesystem. This is a step to put "struct ctl_table"
into .rodata throughout the kernel.

The patch was created with the following coccinelle script:

@@
identifier func, head, ctl;
@@

int func(
struct ctl_table_header *head,
- struct ctl_table *ctl)
+ const struct ctl_table *ctl)
{ ... }

(insert_entry() from fs/proc/proc_sysctl.c is a false-positive)

No additional occurrences of '.permissions =' were found after a
tree-wide search for places missed by the conccinelle script.

Reviewed-by: Joel Granados <[email protected]>
Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Joel Granados <[email protected]>

show more ...

sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table)

Remove the 'table' argument from set_ownership as it is never used. This
change is a step towards putting "struct ctl_tabl

sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table)

Remove the 'table' argument from set_ownership as it is never used. This
change is a step towards putting "struct ctl_table" into .rodata and
eventually having sysctl core only use "const struct ctl_table".

The patch was created with the following coccinelle script:

@@
identifier func, head, table, uid, gid;
@@

void func(
struct ctl_table_header *head,
- struct ctl_table *table,
kuid_t *uid, kgid_t *gid)
{ ... }

No additional occurrences of 'set_ownership' were found after doing a
tree-wide search.

Reviewed-by: Joel Granados <[email protected]>
Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Joel Granados <[email protected]>

show more ...

sysctl: treewide: constify ctl_table_header::ctl_table_arg

To be able to constify instances of struct ctl_tables it is necessary to
remove ways through which non-const versions are exposed from the

sysctl: treewide: constify ctl_table_header::ctl_table_arg

To be able to constify instances of struct ctl_tables it is necessary to
remove ways through which non-const versions are exposed from the
sysctl core.
One of these is the ctl_table_arg member of struct ctl_table_header.

Constify this reference as a prerequisite for the full constification of
struct ctl_table instances.
No functional change.

Signed-off-by: Thomas Weißschuh <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

sysctl: allow to change limits for posix messages queues

All parameters of posix messages queues (queues_max/msg_max/msgsize_max)
end up being limited by RLIMIT_MSGQUEUE. The code in mqueue_get_ino

sysctl: allow to change limits for posix messages queues

All parameters of posix messages queues (queues_max/msg_max/msgsize_max)
end up being limited by RLIMIT_MSGQUEUE. The code in mqueue_get_inode is
where that limiting happens.

The RLIMIT_MSGQUEUE is bound to the user namespace and is counted
hierarchically.

We can allow root in the user namespace to modify the posix messages
queues parameters.

Link: https://lkml.kernel.org/r/6ad67f23d1459a4f4339f74aa73bac0ecf3995e1.1705333426.git.legion@kernel.org
Signed-off-by: Alexey Gladkov <[email protected]>
Signed-off-by: Eric W. Biederman <[email protected]>
Link: https://lkml.kernel.org/r/7eb21211c8622e91d226e63416b1b93c079f60ee.1663756794.git.legion@kernel.org
Cc: Christian Brauner <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Joel Granados <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

sysctl: Add a size arg to __register_sysctl_table

We make these changes in order to prepare __register_sysctl_table and
its callers for when we remove the sentinel element (empty element at
the end

sysctl: Add a size arg to __register_sysctl_table

We make these changes in order to prepare __register_sysctl_table and
its callers for when we remove the sentinel element (empty element at
the end of ctl_table arrays). We don't actually remove any sentinels in
this commit, but we *do* make sure to use ARRAY_SIZE so the table_size
is available when the removal occurs.

We add a table_size argument to __register_sysctl_table and adjust
callers, all of which pass ctl_table pointers and need an explicit call
to ARRAY_SIZE. We implement a size calculation in register_net_sysctl in
order to forward the size of the array pointer received from the network
register calls.

The new table_size argument does not yet have any effect in the
init_header call which is still dependent on the sentinel's presence.
table_size *does* however drive the `kzalloc` allocation in
__register_sysctl_table with no adverse effects as the allocated memory
is either one element greater than the calculated ctl_table array (for
the calls in ipc_sysctl.c, mq_sysctl.c and ucount.c) or the exact size
of the calculated ctl_table array (for the call from sysctl_net.c and
register_sysctl). This approach will allows us to "just" remove the
sentinel without further changes to __register_sysctl_table as
table_size will represent the exact size for all the callers at that
point.

Signed-off-by: Joel Granados <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

ipc: Store mqueue sysctls in the ipc namespace

Right now, the mqueue sysctls take ipc namespaces into account in a
rather hacky way. This works in most cases, but does not respect the
user namespace

ipc: Store mqueue sysctls in the ipc namespace

Right now, the mqueue sysctls take ipc namespaces into account in a
rather hacky way. This works in most cases, but does not respect the
user namespace.

Within the user namespace, the user cannot change the /proc/sys/fs/mqueue/*
parametres. This poses a problem in the rootless containers.

To solve this I changed the implementation of the mqueue sysctls just
like some other sysctls.

So far, the changes do not provide additional access to files. This will
be done in a future patch.

v3:
* Don't implemenet set_permissions to keep the current behavior.

v2:
* Fixed compilation problem if CONFIG_POSIX_MQUEUE_SYSCTL is not
specified.

Reported-by: kernel test robot <[email protected]>
Signed-off-by: Alexey Gladkov <[email protected]>
Link: https://lkml.kernel.org/r/b0ccbb2489119f1f20c737cf1930c3a9c4e4243a.1644862280.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

sysctl: pass kernel pointers to ->proc_handler

Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from u

sysctl: pass kernel pointers to ->proc_handler

Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from userspace in common code. This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Andrey Ignatov <[email protected]>
Signed-off-by: Al Viro <[email protected]>

show more ...

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

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 version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Armijn Hemel <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

ipc: convert use of typedef ctl_table to struct ctl_table

This typedef is unnecessary and should just be removed.

Signed-off-by: Joe Perches <[email protected]>
Signed-off-by: Andrew Morton <akpm@lin

ipc: convert use of typedef ctl_table to struct ctl_table

This typedef is unnecessary and should just be removed.

Signed-off-by: Joe Perches <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ipc,mqueue: remove limits for the amount of system-wide queues

Commit 93e6f119c0ce ("ipc/mqueue: cleanup definition names and
locations") added global hardcoded limits to the amount of message
queue

ipc,mqueue: remove limits for the amount of system-wide queues

Commit 93e6f119c0ce ("ipc/mqueue: cleanup definition names and
locations") added global hardcoded limits to the amount of message
queues that can be created. While these limits are per-namespace,
reality is that it ends up breaking userspace applications.
Historically users have, at least in theory, been able to create up to
INT_MAX queues, and limiting it to just 1024 is way too low and dramatic
for some workloads and use cases. For instance, Madars reports:

"This update imposes bad limits on our multi-process application. As
our app uses approaches that each process opens its own set of queues
(usually something about 3-5 queues per process). In some scenarios
we might run up to 3000 processes or more (which of-course for linux
is not a problem). Thus we might need up to 9000 queues or more. All
processes run under one user."

Other affected users can be found in launchpad bug #1155695:
https://bugs.launchpad.net/ubuntu/+source/manpages/+bug/1155695

Instead of increasing this limit, revert it entirely and fallback to the
original way of dealing queue limits -- where once a user's resource
limit is reached, and all memory is used, new queues cannot be created.

Signed-off-by: Davidlohr Bueso <[email protected]>
Reported-by: Madars Vitolins <[email protected]>
Acked-by: Doug Ledford <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: <[email protected]> [3.5+]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

mqueue: separate mqueue default value from maximum value

Commit b231cca4381e ("message queues: increase range limits") changed
mqueue default value when attr parameter is specified NULL from hard
co

mqueue: separate mqueue default value from maximum value

Commit b231cca4381e ("message queues: increase range limits") changed
mqueue default value when attr parameter is specified NULL from hard
coded value to fs.mqueue.{msg,msgsize}_max sysctl value.

This made large side effect. When user need to use two mqueue
applications 1) using !NULL attr parameter and it require big message
size and 2) using NULL attr parameter and only need small size message,
app (1) require to raise fs.mqueue.msgsize_max and app (2) consume large
memory size even though it doesn't need.

Doug Ledford propsed to switch back it to static hard coded value.
However it also has a compatibility problem. Some applications might
started depend on the default value is tunable.

The solution is to separate default value from maximum value.

Signed-off-by: KOSAKI Motohiro <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
Acked-by: Doug Ledford <[email protected]>
Acked-by: Joe Korty <[email protected]>
Cc: Amerigo Wang <[email protected]>
Acked-by: Serge E. Hallyn <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ipc/mqueue: cleanup definition names and locations

Since commit b231cca4381e ("message queues: increase range limits") on
Oct 18, 2008, calls to mq_open() that did not pass in an attribute
struct an

ipc/mqueue: cleanup definition names and locations

Since commit b231cca4381e ("message queues: increase range limits") on
Oct 18, 2008, calls to mq_open() that did not pass in an attribute
struct and expected to get default values for the size of the queue and
the max message size now get the system wide maximums instead of
hardwired defaults like they used to get.

This was uncovered when one of the earlier patches in this patch set
increased the default system wide maximums at the same time it increased
the hard ceiling on the system wide maximums (a customer specifically
needed the hard ceiling brought back up, the new ceiling that commit
b231cca4381e introduced was too low for their production systems). By
increasing the default maximums and not realising they were tied to any
attempt to create a message queue without an attribute struct, I had
inadvertently made it such that all message queue creation attempts
without an attribute struct were failing because the new default
maximums would create a queue that exceeded the default rlimit for
message queue bytes.

As a result, the system wide defaults were brought back down to their
previous levels, and the system wide ceilings on the maximums were
raised to meet the customer's needs. However, the fact that the no
attribute struct behavior of mq_open() could be broken by changing the
system wide maximums for message queues was seen as fundamentally broken
itself. So we hardwired the no attribute case back like it used to be.
But, then we realized that on the very off chance that some piece of
software in the wild depended on that behavior, we could work around
that issue by adding two new knobs to /proc that allowed setting the
defaults for message queues created without an attr struct separately
from the system wide maximums.

What is not an option IMO is to leave the current behavior in place. No
piece of software should ever rely on setting the system wide maximums
in order to get a desired message queue. Such a reliance would be so
fundamentally multitasking OS unfriendly as to not really be tolerable.
Fortunately, we don't know of any software in the wild that uses this
except for a regression test program that caught the issue in the first
place. If there is though, we have made accommodations with the two new
/proc knobs (and that's all the accommodations such fundamentally broken
software can be allowed)..

This patch:

The various defines for minimums and maximums of the sysctl controllable
mqueue values are scattered amongst different files and named
inconsistently. Move them all into ipc_namespace.h and make them have
consistent names. Additionally, make the number of queues per namespace
also have a minimum and maximum and use the same sysctl function as the
other two settable variables.

Signed-off-by: Doug Ledford <[email protected]>
Acked-by: Serge E. Hallyn <[email protected]>
Cc: Amerigo Wang <[email protected]>
Cc: Joe Korty <[email protected]>
Cc: Jiri Slaby <[email protected]>
Acked-by: KOSAKI Motohiro <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

sysctl ipc: Remove dead binary sysctl support code.

Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name
and .strategy members of sysctl tables are dead code. Remove them.

Signed-o

sysctl ipc: Remove dead binary sysctl support code.

Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name
and .strategy members of sysctl tables are dead code. Remove them.

Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

sysctl: remove "struct file *" argument of ->proc_handler

It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places

sysctl: remove "struct file *" argument of ->proc_handler

It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places at arch/frv for some reason.

Signed-off-by: Alexey Dobriyan <[email protected]>
Cc: David Howells <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: James Morris <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

namespaces: move get_mq() inside #ifdef CONFIG_SYSCTL

| ipc/mq_sysctl.c:26: warning: 'get_mq' defined but not used

Signed-off-by: Geert Uytterhoeven <[email protected]>
Acked-by: Serge

namespaces: move get_mq() inside #ifdef CONFIG_SYSCTL

| ipc/mq_sysctl.c:26: warning: 'get_mq' defined but not used

Signed-off-by: Geert Uytterhoeven <[email protected]>
Acked-by: Serge Hallyn <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

namespaces: mqueue namespace: adapt sysctl

Largely inspired from ipc/ipc_sysctl.c. This patch isolates the mqueue
sysctl stuff in its own file.

[[email protected]: build fix]
Signed-off-by

namespaces: mqueue namespace: adapt sysctl

Largely inspired from ipc/ipc_sysctl.c. This patch isolates the mqueue
sysctl stuff in its own file.

[[email protected]: build fix]
Signed-off-by: Cedric Le Goater <[email protected]>
Signed-off-by: Nadia Derbey <[email protected]>
Signed-off-by: Serge E. Hallyn <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...