linux/fs/proc/proc_sysctl.c, branch v6.0

Merge tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

2022-05-26T23:57:20Z

Pull sysctl updates from Luis Chamberlain: "For two kernel releases now kernel/sysctl.c has been being cleaned up slowly, since the tables were grossly long, sprinkled with tons of #ifdefs and all this caused merge conflicts with one susbystem or another. This tree was put together to help try to avoid conflicts with these cleanups going on different trees at time. So nothing exciting on this pull request, just cleanups. Thanks a lot to the Uniontech and Huawei folks for doing some of this nasty work" * tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (28 commits) sched: Fix build warning without CONFIG_SYSCTL reboot: Fix build warning without CONFIG_SYSCTL kernel/kexec_core: move kexec_core sysctls into its own file sysctl: minor cleanup in new_dir() ftrace: fix building with SYSCTL=y but DYNAMIC_FTRACE=n fs/proc: Introduce list_for_each_table_entry for proc sysctl mm: fix unused variable kernel warning when SYSCTL=n latencytop: move sysctl to its own file ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y ftrace: Fix build warning ftrace: move sysctl_ftrace_enabled to ftrace.c kernel/do_mount_initrd: move real_root_dev sysctls to its own file kernel/delayacct: move delayacct sysctls to its own file kernel/acct: move acct sysctls to its own file kernel/panic: move panic sysctls to its own file kernel/lockdep: move lockdep sysctls to its own file mm: move page-writeback sysctls to their own file mm: move oom_kill sysctls to their own file kernel/reboot: move reboot sysctls to its own file sched: Move energy_aware sysctls to topology.c ...

memcg: accounting for objects allocated for new netdevice

2022-05-05T02:16:46Z

Creating a new netdevice allocates at least ~50Kb of memory for various kernel objects, but only ~5Kb of them are accounted to memcg. As a result, creating an unlimited number of netdevice inside a memcg-limited container does not fall within memcg restrictions, consumes a significant part of the host's memory, can cause global OOM and lead to random kills of host processes. The main consumers of non-accounted memory are: ~10Kb 80+ kernfs nodes ~6Kb ipv6_add_dev() allocations 6Kb __register_sysctl_table() allocations 4Kb neigh_sysctl_register() allocations 4Kb __devinet_sysctl_register() allocations 4Kb __addrconf_sysctl_register() allocations Accounting of these objects allows to increase the share of memcg-related memory up to 60-70% (~38Kb accounted vs ~54Kb total for dummy netdevice on typical VM with default Fedora 35 kernel) and this should be enough to somehow protect the host from misuse inside container. Other related objects are quite small and may not be taken into account to minimize the expected performance degradation. It should be separately mentonied ~300 bytes of percpu allocation of struct ipstats_mib in snmp6_alloc_dev(), on huge multi-cpu nodes it can become the main consumer of memory. This patch does not enables kernfs accounting as it affects other parts of the kernel and should be discussed separately. However, even without kernfs, this patch significantly improves the current situation and allows to take into account more than half of all netdevice allocations. Signed-off-by: Vasily Averin Acked-by: Luis Chamberlain Link: https://lore.kernel.org/r/354a0a5f-9ec3-a25c-3215-304eab2157bc@openvz.org Signed-off-by: Jakub Kicinski

net: sysctl: introduce sysctl SYSCTL_THREE

2022-05-03T08:15:06Z

This patch introdues the SYSCTL_THREE. KUnit: [00:10:14] ================ sysctl_test (10 subtests) ================= [00:10:14] [PASSED] sysctl_test_api_dointvec_null_tbl_data [00:10:14] [PASSED] sysctl_test_api_dointvec_table_maxlen_unset [00:10:14] [PASSED] sysctl_test_api_dointvec_table_len_is_zero [00:10:14] [PASSED] sysctl_test_api_dointvec_table_read_but_position_set [00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_positive [00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_negative [00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_positive [00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_negative [00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_less_int_min [00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_greater_int_max [00:10:14] =================== [PASSED] sysctl_test =================== ./run_kselftest.sh -c sysctl ... ok 1 selftests: sysctl: sysctl.sh Cc: Luis Chamberlain Cc: Kees Cook Cc: Iurii Zaikin Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Hideaki YOSHIFUJI Cc: David Ahern Cc: Simon Horman Cc: Julian Anastasov Cc: Pablo Neira Ayuso Cc: Jozsef Kadlecsik Cc: Florian Westphal Cc: Shuah Khan Cc: Andrew Morton Cc: Alexei Starovoitov Cc: Eric Dumazet Cc: Lorenz Bauer Cc: Akhmat Karakotov Signed-off-by: Tonghao Zhang Reviewed-by: Simon Horman Signed-off-by: Paolo Abeni

sysctl: minor cleanup in new_dir()

2022-04-25T20:00:40Z

Byte zeroing is not required here, since memory was allocated by kzalloc() Signed-off-by: Vasily Averin Signed-off-by: Luis Chamberlain

fs/proc: Introduce list_for_each_table_entry for proc sysctl

2022-04-21T18:40:59Z

Use the list_for_each_table_entry macro to optimize the scenario of traverse ctl_table. This make the code neater and easier to understand. Suggested-by: Davidlohr Bueso Signed-off-by: Meng Tang [updated the sysctl_check_table() hunk due to some changes upstream] Signed-off-by: Luis Chamberlain

kernel/sysctl.c: rename sysctl_init() to sysctl_init_bases()

2022-01-22T06:33:36Z

Rename sysctl_init() to sysctl_init_bases() so to reflect exactly what this is doing. Link: https://lkml.kernel.org/r/20211129211943.640266-4-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Cc: Al Viro Cc: Anil S Keshavamurthy Cc: Antti Palosaari Cc: Christian Brauner Cc: "David S. Miller" Cc: Eric Biederman Cc: Eric Biggers Cc: Iurii Zaikin Cc: Kees Cook Cc: Lukas Middendorf Cc: Masami Hiramatsu Cc: "Naveen N. Rao" Cc: Stephen Kitt Cc: Xiaoming Ni Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysctl: add and use base directory declarer and registration helper

2022-01-22T06:33:36Z

Patch series "sysctl: add and use base directory declarer and registration helper". In this patch series we start addressing base directories, and so we start with the "fs" sysctls. The end goal is we end up completely moving all "fs" sysctl knobs out from kernel/sysctl. This patch (of 6): Add a set of helpers which can be used to declare and register base directory sysctls on their own. We do this so we can later move each of the base sysctl directories like "fs", "kernel", etc, to their own respective files instead of shoving the declarations and registrations all on kernel/sysctl.c. The lazy approach has caught up and with this, we just end up extending the list of base directories / sysctls on one file and this makes maintenance difficult due to merge conflicts from many developers. The declarations are used first by kernel/sysctl.c for registration its own base which over time we'll try to clean up. It will be used in the next patch to demonstrate how to cleanly deal with base sysctl directories. [mcgrof@kernel.org: null-terminate the ctl_table arrays] Link: https://lkml.kernel.org/r/YafJY3rXDYnjK/gs@bombadil.infradead.org Link: https://lkml.kernel.org/r/20211129211943.640266-1-mcgrof@kernel.org Link: https://lkml.kernel.org/r/20211129211943.640266-2-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Cc: Al Viro Cc: Kees Cook Cc: Iurii Zaikin Cc: Xiaoming Ni Cc: Eric Biederman Cc: Stephen Kitt Cc: Lukas Middendorf Cc: Antti Palosaari Cc: Christian Brauner Cc: Eric Biggers Cc: "Naveen N. Rao" Cc: "David S. Miller" Cc: Masami Hiramatsu Cc: Anil S Keshavamurthy Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysctl: move maxolduid as a sysctl specific const

2022-01-22T06:33:36Z

The maxolduid value is only shared for sysctl purposes for use on a max range. Just stuff this into our shared const array. [akpm@linux-foundation.org: fix sysctl_vals[], per Mickaël] Link: https://lkml.kernel.org/r/20211129205548.605569-5-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Signed-off-by: Mickaël Salaün Cc: Al Viro Cc: Andy Shevchenko Cc: Antti Palosaari Cc: Eric Biederman Cc: Iurii Zaikin Cc: "J. Bruce Fields" Cc: Jeff Layton Cc: Kees Cook Cc: Lukas Middendorf Cc: Stephen Kitt Cc: Xiaoming Ni Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysctl: share unsigned long const values

2022-01-22T06:33:35Z

Provide a way to share unsigned long values. This will allow others to not have to re-invent these values. Link: https://lkml.kernel.org/r/20211124231435.1445213-9-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Cc: Al Viro Cc: Amir Goldstein Cc: Andy Shevchenko Cc: Antti Palosaari Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Benjamin LaHaise Cc: Clemens Ladisch Cc: David Airlie Cc: Douglas Gilbert Cc: Eric Biederman Cc: Greg Kroah-Hartman Cc: Iurii Zaikin Cc: James E.J. Bottomley Cc: Jani Nikula Cc: Jani Nikula Cc: Jan Kara Cc: Joel Becker Cc: John Ogness Cc: Joonas Lahtinen Cc: Joseph Qi Cc: Julia Lawall Cc: Kees Cook Cc: Lukas Middendorf Cc: Mark Fasheh Cc: Martin K. Petersen Cc: Paul Turner Cc: Peter Zijlstra Cc: Petr Mladek Cc: Phillip Potter Cc: Qing Wang Cc: "Rafael J. Wysocki" Cc: Rodrigo Vivi Cc: Sebastian Reichel Cc: Sergey Senozhatsky Cc: Stephen Kitt Cc: Steven Rostedt (VMware) Cc: Suren Baghdasaryan Cc: Tetsuo Handa Cc: "Theodore Ts'o" Cc: Xiaoming Ni Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sysctl: add helper to register a sysctl mount point

2022-01-22T06:33:35Z

The way to create a subdirectory on top of sysctl_mount_point is a bit obscure, and *why* we do that even so more. Provide a helper which makes it clear why we do this. [akpm@linux-foundation.org: export register_sysctl_mount_point() to modules] Link: https://lkml.kernel.org/r/20211124231435.1445213-4-mcgrof@kernel.org Signed-off-by: Luis Chamberlain Suggested-by: "Eric W. Biederman" Cc: Al Viro Cc: Amir Goldstein Cc: Andy Shevchenko Cc: Antti Palosaari Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Benjamin LaHaise Cc: Clemens Ladisch Cc: David Airlie Cc: Douglas Gilbert Cc: Greg Kroah-Hartman Cc: Iurii Zaikin Cc: James E.J. Bottomley Cc: Jani Nikula Cc: Jani Nikula Cc: Jan Kara Cc: Joel Becker Cc: John Ogness Cc: Joonas Lahtinen Cc: Joseph Qi Cc: Julia Lawall Cc: Kees Cook Cc: Lukas Middendorf Cc: Mark Fasheh Cc: Martin K. Petersen Cc: Paul Turner Cc: Peter Zijlstra Cc: Petr Mladek Cc: Phillip Potter Cc: Qing Wang Cc: "Rafael J. Wysocki" Cc: Rodrigo Vivi Cc: Sebastian Reichel Cc: Sergey Senozhatsky Cc: Stephen Kitt Cc: Steven Rostedt (VMware) Cc: Suren Baghdasaryan Cc: Tetsuo Handa Cc: "Theodore Ts'o" Cc: Xiaoming Ni Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds