kernel/linux.git/ipc/mq_sysctl.c, branch v6.6.151

sysctl: treewide: constify ctl_table_header::ctl_table_arg

2026-08-09T18:22:03+00:00

[ Upstream commit bfa858f220ab8c950dd3e1310fee61950d0ecdae ] 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 Reviewed-by: Kees Cook Signed-off-by: David S. Miller Stable-dep-of: f8d5e7846025 ("sctp: avoid auth_enable sysctl UAF during netns teardown") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

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

2024-08-11T10:47:13+00:00

[ Upstream commit 520713a93d550406dae14d49cdb8778d70cecdfd ] 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 Signed-off-by: Thomas Weißschuh Signed-off-by: Joel Granados Stable-dep-of: 98ca62ba9e2b ("sysctl: always initialize i_uid/i_gid") Signed-off-by: Sasha Levin

sysctl: allow to change limits for posix messages queues

2024-08-11T10:47:12+00:00

[ Upstream commit f9436a5d0497f759330d07e1189565edd4456be8 ] 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 Signed-off-by: Eric W. Biederman Link: https://lkml.kernel.org/r/7eb21211c8622e91d226e63416b1b93c079f60ee.1663756794.git.legion@kernel.org Cc: Christian Brauner Cc: Davidlohr Bueso Cc: Joel Granados Cc: Kees Cook Cc: Luis Chamberlain Cc: Manfred Spraul Signed-off-by: Andrew Morton Stable-dep-of: 98ca62ba9e2b ("sysctl: always initialize i_uid/i_gid") Signed-off-by: Sasha Levin

sysctl: Add a size arg to __register_sysctl_table

2023-08-15T22:26:17+00:00

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 Signed-off-by: Luis Chamberlain

ipc: Store mqueue sysctls in the ipc namespace

2022-03-08T19:39:40+00:00

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 Signed-off-by: Alexey Gladkov Link: https://lkml.kernel.org/r/b0ccbb2489119f1f20c737cf1930c3a9c4e4243a.1644862280.git.legion@kernel.org Signed-off-by: Eric W. Biederman

sysctl: pass kernel pointers to ->proc_handler

2020-04-27T06:07:40+00:00

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 Acked-by: Andrey Ignatov Signed-off-by: Al Viro

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

2019-06-05T15:37:17+00:00

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 Reviewed-by: Allison Randal Reviewed-by: Armijn Hemel Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman

ipc: convert use of typedef ctl_table to struct ctl_table

2014-06-06T23:08:16+00:00

This typedef is unnecessary and should just be removed. Signed-off-by: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

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

2014-02-25T23:25:45+00:00

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 Reported-by: Madars Vitolins Acked-by: Doug Ledford Cc: Manfred Spraul Cc: [3.5+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mqueue: separate mqueue default value from maximum value

2012-06-01T00:49:31+00:00

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 Signed-off-by: Doug Ledford Acked-by: Doug Ledford Acked-by: Joe Korty Cc: Amerigo Wang Acked-by: Serge E. Hallyn Cc: Jiri Slaby Cc: Manfred Spraul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds