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2023-01-25kernel/params.c: Use kstrtobool() instead of strtobool()Christophe JAILLET1-1/+2
strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. While at it, include the corresponding header file (<linux/kstrtox.h>) Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-12-16Merge tag 'driver-core-6.2-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core and kernfs changes for 6.2-rc1. The "big" change in here is the addition of a new macro, container_of_const() that will preserve the "const-ness" of a pointer passed into it. The "problem" of the current container_of() macro is that if you pass in a "const *", out of it can comes a non-const pointer unless you specifically ask for it. For many usages, we want to preserve the "const" attribute by using the same call. For a specific example, this series changes the kobj_to_dev() macro to use it, allowing it to be used no matter what the const value is. This prevents every subsystem from having to declare 2 different individual macros (i.e. kobj_const_to_dev() and kobj_to_dev()) and having the compiler enforce the const value at build time, which having 2 macros would not do either. The driver for all of this have been discussions with the Rust kernel developers as to how to properly mark driver core, and kobject, objects as being "non-mutable". The changes to the kobject and driver core in this pull request are the result of that, as there are lots of paths where kobjects and device pointers are not modified at all, so marking them as "const" allows the compiler to enforce this. So, a nice side affect of the Rust development effort has been already to clean up the driver core code to be more obvious about object rules. All of this has been bike-shedded in quite a lot of detail on lkml with different names and implementations resulting in the tiny version we have in here, much better than my original proposal. Lots of subsystem maintainers have acked the changes as well. Other than this change, included in here are smaller stuff like: - kernfs fixes and updates to handle lock contention better - vmlinux.lds.h fixes and updates - sysfs and debugfs documentation updates - device property updates All of these have been in the linux-next tree for quite a while with no problems" * tag 'driver-core-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (58 commits) device property: Fix documentation for fwnode_get_next_parent() firmware_loader: fix up to_fw_sysfs() to preserve const usb.h: take advantage of container_of_const() device.h: move kobj_to_dev() to use container_of_const() container_of: add container_of_const() that preserves const-ness of the pointer driver core: fix up missed drivers/s390/char/hmcdrv_dev.c class.devnode() conversion. driver core: fix up missed scsi/cxlflash class.devnode() conversion. driver core: fix up some missing class.devnode() conversions. driver core: make struct class.devnode() take a const * driver core: make struct class.dev_uevent() take a const * cacheinfo: Remove of_node_put() for fw_token device property: Add a blank line in Kconfig of tests device property: Rename goto label to be more precise device property: Move PROPERTY_ENTRY_BOOL() a bit down device property: Get rid of __PROPERTY_ENTRY_ARRAY_EL*SIZE*() kernfs: fix all kernel-doc warnings and multiple typos driver core: pass a const * into of_device_uevent() kobject: kset_uevent_ops: make name() callback take a const * kobject: kset_uevent_ops: make filter() callback take a const * kobject: make kobject_namespace take a const * ...
2022-11-22kobject: kset_uevent_ops: make filter() callback take a const *Greg Kroah-Hartman1-1/+1
The filter() callback in struct kset_uevent_ops does not modify the kobject passed into it, so make the pointer const to enforce this restriction. When doing so, fix up all existing filter() callbacks to have the correct signature to preserve the build. Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: linux-media@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: linaro-mm-sig@lists.linaro.org Acked-by: Rafael J. Wysocki <rafael@kernel.org> Acked-by: Christian König <christian.koenig@amd.com> for the changes to Link: https://lore.kernel.org/r/20221121094649.1556002-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-11kernel/params.c: defer most of param_sysfs_init() to late_initcall timeRasmus Villemoes1-2/+19
param_sysfs_init(), and in particular param_sysfs_builtin() is rather time-consuming; for my board, it currently takes about 30ms. That amounts to about 3% of the time budget I have from U-Boot hands over control to linux and linux must assume responsibility for keeping the external watchdog happy. We must still continue to initialize module_kset at subsys_initcall time, since otherwise any request_module() would fail in mod_sysfs_init(). However, the bulk of the work in param_sysfs_builtin(), namely populating /sys/module/*/version and/or /sys/module/*/parameters/ for builtin modules, can be deferred to late_initcall time - there's no userspace yet anyway to observe contents of /sys or the lack thereof. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-11-11module: remove redundant module_sysfs_initialized variableRasmus Villemoes1-2/+0
The variable module_sysfs_initialized is used for checking whether module_kset has been initialized. Checking module_kset itself works just fine for that. This is a leftover from commit 7405c1e15edf ("kset: convert /sys/module to use kset_create"). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Miroslav Benes <mbenes@suse.cz> [mcgrof: adjusted commit log as suggested by Christophe Leroy] Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2021-12-28kobject: remove kset from struct kset_uevent_ops callbacksGreg Kroah-Hartman1-1/+1
There is no need to pass the pointer to the kset in the struct kset_uevent_ops callbacks as no one uses it, so just remove that pointer entirely. Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Wedson Almeida Filho <wedsonaf@google.com> Link: https://lore.kernel.org/r/20211227163924.3970661-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-27driver core: make kobj_type constant.Wedson Almeida Filho1-1/+1
This way instances of kobj_type (which contain function pointers) can be stored in .rodata, which means that they cannot be [easily/accidentally] modified at runtime. Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Link: https://lore.kernel.org/r/20211224231345.777370-1-wedsonaf@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-16params: lift param_set_uint_minmax to common codeSagi Grimberg1-0/+18
It is a useful helper hence move it to common code so others can enjoy it. Suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-12-17Merge tag 'modules-for-v5.11' of ↵Linus Torvalds1-6/+4
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Summary of modules changes for the 5.11 merge window: - Fix a race condition between systemd/udev and the module loader. The module loader was sending a uevent before the module was fully initialized (i.e., before its init function has been called). This means udev can start processing the module uevent before the module has finished initializing, and some udev rules expect that the module has initialized already upon receiving the uevent. This resulted in some systemd mount units failing if udev processes the event faster than the module can finish init. This is fixed by delaying the uevent until after the module has called its init routine. - Make the linker array sections for kernel params and module version attributes more robust by switching to use the alignment of the type in question. Namely, linker section arrays will be constructed using the alignment required by the struct (using __alignof__()) as opposed to a specific value such as sizeof(void *) or sizeof(long). This is less likely to cause breakages should the size of the type ever change (Johan Hovold) - Fix module state inconsistency by setting it back to GOING when a module fails to load and is on its way out (Miroslav Benes) - Some comment and code cleanups (Sergey Shtylyov)" * tag 'modules-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: delay kobject uevent until after module init call module: drop semicolon from version macro init: use type alignment for kernel parameters params: clean up module-param macros params: use type alignment for kernel parameters params: drop redundant "unused" attributes module: simplify version-attribute handling module: drop version-attribute alignment module: fix comment style module: add more 'kernel-doc' comments module: fix up 'kernel-doc' comments module: only handle errors with the *switch* statement in module_sig_check() module: avoid *goto*s in module_sig_check() module: merge repetitive strings in module_sig_check() module: set MODULE_STATE_GOING state when a module fails to load
2020-11-25module: simplify version-attribute handlingJohan Hovold1-6/+4
Instead of using the array-of-pointers trick to avoid having gcc mess up the built-in module-version array stride, specify type alignment when declaring entries to prevent gcc from increasing alignment. This is essentially an alternative (one-line) fix to the problem addressed by commit b4bc842802db ("module: deal with alignment issues in built-in module versions"). gcc can increase the alignment of larger objects with static extent as an optimisation, but this can be suppressed by using the aligned attribute when declaring variables. Note that we have been relying on this behaviour for kernel parameters for 16 years and it indeed hasn't changed since the introduction of the aligned attribute in gcc-3.1. Link: https://lore.kernel.org/lkml/20201103175711.10731-1-johan@kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2020-10-29params: Replace zero-length array with flexible-array memberGustavo A. R. Silva1-1/+1
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-07-28moduleparams: Add hexint type parameterPaul Menzel1-8/+9
For bitmasks printing values in hex is more convenient. Prefix with `0x` to make it clear, that it’s a hex value, and pad it out. Using the helper for `amdgpu.ppfeaturemask`, it will look like below. Before: $ more /sys/module/amdgpu/parameters/ppfeaturemask 4294950911 After: $ more /sys/module/amdgpu/parameters/ppfeaturemask 0xffffbfff Cc: linux-kernel@vger.kernel.org Cc: amd-gfx@lists.freedesktop.org Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/374726/
2020-07-28kernel/params.c: Align last argument with a tabPaul Menzel1-8/+8
The second and third arguments are aligned with tabs, so do the same for the fourth. Cc: linux-kernel@vger.kernel.org Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Link: https://lore.kernel.org/patchwork/patch/1267600/
2019-08-19lockdown: Lock down module params that specify hardware parameters (eg. ioport)David Howells1-5/+16
Provided an annotation for module parameters that specify hardware parameters (such as io ports, iomem addresses, irqs, dma channels, fixed dma buffers and other types). Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Jessica Yu <jeyu@kernel.org> Signed-off-by: James Morris <jmorris@namei.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner1-13/+1
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 either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-11kernel/params.c: downgrade warning for unsafe parametersChris Wilson1-2/+2
As using an unsafe module parameter is, by its very definition, an expected user action, emitting a warning is overkill. Nothing has yet gone wrong, and we add a taint flag for any future oops should something actually go wrong. So instead of having a user controllable pr_warn, downgrade it to a pr_notice for "a normal, but significant condition". We make use of unsafe kernel parameters in igt (https://cgit.freedesktop.org/drm/igt-gpu-tools/) (we have not yet succeeded in removing all such debugging options), which generates a warning and taints the kernel. The warning is unhelpful as we then need to filter it out again as we check that every test themselves do not provoke any kernel warnings. Link: http://lkml.kernel.org/r/20180226151919.9674-1-chris@chris-wilson.co.uk Fixes: 91f9d330cc14 ("module: make it possible to have unsafe, tainting module params") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Acked-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jean Delvare <khali@linux-fr.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Petri Latvala <petri.latvala@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: improve STANDARD_PARAM_DEF readabilityJean Delvare1-8/+8
Align the parameters passed to STANDARD_PARAM_DEF for clarity. Link: http://lkml.kernel.org/r/20170928162728.756143cc@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: fix an overflow in param_attr_showJean Delvare1-10/+7
Function param_attr_show could overflow the buffer it is operating on. The buffer size is PAGE_SIZE, and the string returned by attribute->param->ops->get is generated by scnprintf(buffer, PAGE_SIZE, ...) so it could be PAGE_SIZE - 1 long, with the terminating '\0' at the very end of the buffer. Calling strcat(..., "\n") on this isn't safe, as the '\0' will be replaced by '\n' (OK) and then another '\0' will be added past the end of the buffer (not OK.) Simply add the trailing '\n' when writing the attribute contents to the buffer originally. This is safe, and also faster. Credits to Teradata for discovering this issue. Link: http://lkml.kernel.org/r/20170928162602.60c379c7@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: fix the maximum length in param_get_stringJean Delvare1-1/+1
The length parameter of strlcpy() is supposed to reflect the size of the target buffer, not of the source string. Harmless in this case as the buffer is PAGE_SIZE long and the source string is always much shorter than this, but conceptually wrong, so let's fix it. Link: http://lkml.kernel.org/r/20170928162515.24846b4f@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: align add_sysfs_param documentation with codeJean Delvare1-1/+1
This parameter is named kp, so the documentation should use that. Fixes: 9b473de87209 ("param: Fix duplicate module prefixes") Link: http://lkml.kernel.org/r/20170919142656.64aea59e@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-18boot/param: Move next_arg() function to lib/cmdline.c for later reuseBaoquan He1-52/+0
next_arg() will be used to parse boot parameters in the x86/boot/compressed code, so move it to lib/cmdline.c for better code reuse. No change in functionality. Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Cc: Jens Axboe <axboe@fb.com> Cc: Jessica Yu <jeyu@redhat.com> Cc: Johannes Berg <johannes.berg@intel.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Larry Finger <Larry.Finger@lwfinger.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Cc: dave.jiang@intel.com Cc: dyoung@redhat.com Cc: keescook@chromium.org Cc: zijun_hu <zijun_hu@htc.com> Link: http://lkml.kernel.org/r/1492436099-4017-2-git-send-email-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-09Merge tag 'modules-next-for-linus' of ↵Linus Torvalds1-8/+9
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Nothing exciting, minor tweaks and cleanups" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: scripts: [modpost] add new sections to white list modpost: Add flag -E for making section mismatches fatal params: don't ignore the rest of cmdline if parse_one() fails modpost: abort if a module symbol is too long
2015-11-06module: export param_free_charp()Dan Streetman1-1/+2
Change the param_free_charp() function from static to exported. It is used by zswap in the next patch ("zswap: use charp for zswap param strings"). Signed-off-by: Dan Streetman <ddstreet@ieee.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Seth Jennings <sjennings@variantweb.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-26params: don't ignore the rest of cmdline if parse_one() failsOleg Nesterov1-8/+9
parse_args() just aborts after it hits an error, so other args at the same initcall level are simply ignored. This can lead to other hard-to-understand problems, for example my testing machine panics during the boot if I pass "locktorture.verbose=true". Change parse_args() to save the err code for return and continue. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-07-01Merge tag 'modules-next-for-linus' of ↵Linus Torvalds1-30/+86
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Main excitement here is Peter Zijlstra's lockless rbtree optimization to speed module address lookup. He found some abusers of the module lock doing that too. A little bit of parameter work here too; including Dan Streetman's breaking up the big param mutex so writing a parameter can load another module (yeah, really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were appended too" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits) modules: only use mod->param_lock if CONFIG_MODULES param: fix module param locks when !CONFIG_SYSFS. rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() module: add per-module param_lock module: make perm const params: suppress unused variable error, warn once just in case code changes. modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'. kernel/module.c: avoid ifdefs for sig_enforce declaration kernel/workqueue.c: remove ifdefs over wq_power_efficient kernel/params.c: export param_ops_bool_enable_only kernel/params.c: generalize bool_enable_only kernel/module.c: use generic module param operaters for sig_enforce kernel/params: constify struct kernel_param_ops uses sysfs: tightened sysfs permission checks module: Rework module_addr_{min,max} module: Use __module_address() for module_address_lookup() module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING module: Optimize __module_address() using a latched RB-tree rbtree: Implement generic latch_tree seqlock: Introduce raw_read_seqcount_latch() ...
2015-06-28modules: only use mod->param_lock if CONFIG_MODULESStephen Rothwell1-0/+4
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-28param: fix module param locks when !CONFIG_SYSFS.Rusty Russell1-4/+14
As Dan Streetman points out, the entire point of locking for is to stop sysfs accesses, so they're elided entirely in the !SYSFS case. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-23module: add per-module param_lockDan Streetman1-19/+31
Add a "param_lock" mutex to each module, and update params.c to use the correct built-in or module mutex while locking kernel params. Remove the kparam_block_sysfs_r/w() macros, replace them with direct calls to kernel_param_[un]lock(module). The kernel param code currently uses a single mutex to protect modification of any and all kernel params. While this generally works, there is one specific problem with it; a module callback function cannot safely load another module, i.e. with request_module() or even with indirect calls such as crypto_has_alg(). If the module to be loaded has any of its params configured (e.g. with a /etc/modprobe.d/* config file), then the attempt will result in a deadlock between the first module param callback waiting for modprobe, and modprobe trying to lock the single kernel param mutex to set the new module's param. This fixes that by using per-module mutexes, so that each individual module is protected against concurrent changes in its own kernel params, but is not blocked by changes to other module params. All built-in modules continue to use the built-in mutex, since they will always be loaded at runtime and references (e.g. request_module(), crypto_has_alg()) to them will never cause load-time param changing. This also simplifies the interface used by modules to block sysfs access to their params; while there are currently functions to block and unblock sysfs param access which are split up by read and write and expect a single kernel param to be passed, their actual operation is identical and applies to all params, not just the one passed to them; they simply lock and unlock the global param mutex. They are replaced with direct calls to kernel_param_[un]lock(THIS_MODULE), which locks THIS_MODULE's param_lock, or if the module is built-in, it locks the built-in mutex. Suggested-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Dan Streetman <ddstreet@ieee.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-23module: make perm constDan Streetman1-5/+3
Change the struct kernel_param.perm field to a const, as it should never be changed. Signed-off-by: Dan Streetman <ddstreet@ieee.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cut from larger patch)
2015-06-23params: suppress unused variable error, warn once just in case code changes.Rusty Russell1-0/+1
It shouldn't fail due to OOM (it's boot time), and already warns if we get two identical names. But you never know what the future holds, and WARN_ON_ONCE() keeps gcc happy with minimal code. Reported-by: Louis Langholtz <lou_langholtz@me.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28kernel/params.c: export param_ops_bool_enable_onlyLuis R. Rodriguez1-0/+1
This will grant access to this helper to code built as modules. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: David Howells <dhowells@redhat.com> Cc: Ming Lei <ming.lei@canonical.com> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Kyle McMartin <kyle@kernel.org> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28kernel/params.c: generalize bool_enable_onlyLuis R. Rodriguez1-0/+30
This takes out the bool_enable_only implementation from the module loading code and generalizes it so that others can make use of it. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: cocci@systeme.lip6.fr Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-28kernel/params: constify struct kernel_param_ops usesLuis R. Rodriguez1-7/+7
Most code already uses consts for the struct kernel_param_ops, sweep the kernel for the last offending stragglers. Other than include/linux/moduleparam.h and kernel/params.c all other changes were generated with the following Coccinelle SmPL patch. Merge conflicts between trees can be handled with Coccinelle. In the future git could get Coccinelle merge support to deal with patch --> fail --> grammar --> Coccinelle --> new patch conflicts automatically for us on patches where the grammar is available and the patch is of high confidence. Consider this a feature request. Test compiled on x86_64 against: * allnoconfig * allmodconfig * allyesconfig @ const_found @ identifier ops; @@ const struct kernel_param_ops ops = { }; @ const_not_found depends on !const_found @ identifier ops; @@ -struct kernel_param_ops ops = { +const struct kernel_param_ops ops = { }; Generated-by: Coccinelle SmPL Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Junio C Hamano <gitster@pobox.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: cocci@systeme.lip6.fr Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-05-20module: add extra argument for parse_params() callbackLuis R. Rodriguez1-4/+7
This adds an extra argument onto parse_params() to be used as a way to make the unused callback a bit more useful and generic by allowing the caller to pass on a data structure of its choice. An example use case is to allow us to easily make module parameters for every module which we will do next. @ parse @ identifier name, args, params, num, level_min, level_max; identifier unknown, param, val, doing; type s16; @@ extern char *parse_args(const char *name, char *args, const struct kernel_param *params, unsigned num, s16 level_min, s16 level_max, + void *arg, int (*unknown)(char *param, char *val, const char *doing + , void *arg )); @ parse_mod @ identifier name, args, params, num, level_min, level_max; identifier unknown, param, val, doing; type s16; @@ char *parse_args(const char *name, char *args, const struct kernel_param *params, unsigned num, s16 level_min, s16 level_max, + void *arg, int (*unknown)(char *param, char *val, const char *doing + , void *arg )) { ... } @ parse_args_found @ expression R, E1, E2, E3, E4, E5, E6; identifier func; @@ ( R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, func); | R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, &func); | R = parse_args(E1, E2, E3, E4, E5, E6, + NULL, NULL); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, func); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, &func); | parse_args(E1, E2, E3, E4, E5, E6, + NULL, NULL); ) @ parse_args_unused depends on parse_args_found @ identifier parse_args_found.func; @@ int func(char *param, char *val, const char *unused + , void *arg ) { ... } @ mod_unused depends on parse_args_found @ identifier parse_args_found.func; expression A1, A2, A3; @@ - func(A1, A2, A3); + func(A1, A2, A3, NULL); Generated-by: Coccinelle SmPL Cc: cocci@systeme.lip6.fr Cc: Tejun Heo <tj@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Christoph Hellwig <hch@infradead.org> Cc: Felipe Contreras <felipe.contreras@gmail.com> Cc: Ewan Milne <emilne@redhat.com> Cc: Jean Delvare <jdelvare@suse.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Jani Nikula <jani.nikula@intel.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-15params: handle quotes properly for values not of form foo="bar".Rusty Russell1-2/+2
When starting kernel with arguments like: init=/bin/sh -c "echo arguments" the trailing double quote is not removed which results in following command being executed: /bin/sh -c 'echo arguments"' Reported-by: Arthur Gautier <baloo@gandi.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-20param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOCRusty Russell1-0/+1
ignore_lockdep is uninitialized, and sysfs_attr_init() doesn't initialize it, so memset to 0. Reported-by: Huang Ying <ying.huang@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-12-23param: initialize store function to NULL if not available.Rusty Russell1-0/+2
I rebased Kees' 'param: do not set store func without write perm' on top of my 'params: cleanup sysfs allocation'. However, my patch uses krealloc which doesn't zero memory, leaving .store unset. Reported-by: Sasha Levin <sasha.levin@oracle.com> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-12-18param: do not set store func without write permKees Cook1-1/+3
When a module_param is defined without DAC write permissions, it can still be changed at runtime and updated. Drivers using a 0444 permission may be surprised that these values can still be changed. For drivers that want to allow updates, any S_IW* flag will set the "store" function as before. Drivers without S_IW* flags will have the "store" function unset, unforcing a read-only value. Drivers that wish neither "store" nor "get" can continue to use "0" for perms to stay out of sysfs entirely. Old behavior: # cd /sys/module/snd/parameters # ls -l total 0 -r--r--r-- 1 root root 4096 Dec 11 13:55 cards_limit -r--r--r-- 1 root root 4096 Dec 11 13:55 major -r--r--r-- 1 root root 4096 Dec 11 13:55 slots # cat major 116 # echo -1 > major -bash: major: Permission denied # chmod u+w major # echo -1 > major # cat major -1 New behavior: ... # chmod u+w major # echo -1 > major -bash: echo: write error: Input/output error Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-11-11params: cleanup sysfs allocationRusty Russell1-51/+44
commit 63662139e519ce06090b2759cf4a1d291b9cc0e2 attempted to patch a leak (which would only happen on OOM, ie. never), but it didn't quite work. This rewrites the code to be as simple as possible. add_sysfs_param() adds a parameter. If it fails, it's the caller's responsibility to clean up the parameters which already exist. The kzalloc-then-always-krealloc pattern is perhaps overly simplistic, but this code has clearly confused people. It worked on me... Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-10-14kernel/param: consolidate __{start,stop}___param[] in <linux/moduleparam.h>Geert Uytterhoeven1-4/+3
Consolidate the various external const and non-const declarations of __start___param[] and __stop___param in <linux/moduleparam.h>. This requires making a few struct kernel_param pointers in kernel/params.c const. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-27param: check for tainting before calling set op.Rusty Russell1-11/+11
This means every set op doesn't need to call it, and it can move into params.c. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-27module: make it possible to have unsafe, tainting module paramsJani Nikula1-0/+11
Add flags field to struct kernel_params, and add the first flag: unsafe parameter. Modifying a kernel parameter with the unsafe flag set, either via the kernel command line or sysfs, will issue a warning and taint the kernel. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jean Delvare <khali@linux-fr.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Jon Mason <jon.mason@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-08-27module: rename KERNEL_PARAM_FL_NOARG to avoid confusionJani Nikula1-3/+3
Make it clear this is about kernel_param_ops, not kernel_param (which will soon have a flags field of its own). No functional changes. Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jean Delvare <khali@linux-fr.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Jon Mason <jon.mason@intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-07-17Add module param type 'ullong'Hannes Reinecke1-0/+1
Some driver might want to pass in an 64-bit value, so introduce a module param type 'ullong'. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ewan Milne <emilne@redhat.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-04-28param: hand arguments after -- straight to initRusty Russell1-11/+14
The kernel passes any args it doesn't need through to init, except it assumes anything containing '.' belongs to the kernel (for a module). This change means all users can clearly distinguish which arguments are for init. For example, the kernel uses debug ("dee-bug") to mean log everything to the console, where systemd uses the debug from the Scandinavian "day-boog" meaning "fail to boot". If a future versions uses argv[] instead of reading /proc/cmdline, this confusion will be avoided. eg: test 'FOO="this is --foo"' -- 'systemd.debug="true true true"' Gives: argv[0] = '/debug-init' argv[1] = 'test' argv[2] = 'systemd.debug=true true true' envp[0] = 'HOME=/' envp[1] = 'TERM=linux' envp[2] = 'FOO=this is --foo' Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-12-04params: improve standard definitionsFelipe Contreras1-16/+9
We are repeating the functionality of kstrtol in param_set_long, and the same for kstrtoint. We can get rid of the extra code by using the right functions. Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-09-28kernel/params: fix handling of signed integer typesJean Delvare1-3/+3
Commit 6072ddc8520b ("kernel: replace strict_strto*() with kstrto*()") broke the handling of signed integer types, fix it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Reported-by: Christian Kujau <lists@nerdbynature.de> Tested-by: Christian Kujau <lists@nerdbynature.de> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12kernel: replace strict_strto*() with kstrto*()Jingoo Han1-7/+7
The usage of strict_strto*() is not preferred, because strict_strto*() is obsolete. Thus, kstrto*() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-03module: Fix mod->mkobj.kobj potentially freed too earlyLi Zhong1-0/+7
DEBUG_KOBJECT_RELEASE helps to find the issue attached below. After some investigation, it seems the reason is: The mod->mkobj.kobj(ffffffffa01600d0 below) is freed together with mod itself in free_module(). However, its children still hold references to it, as the delay caused by DEBUG_KOBJECT_RELEASE. So when the child(holders below) tries to decrease the reference count to its parent in kobject_del(), BUG happens as it tries to access already freed memory. This patch tries to fix it by waiting for the mod->mkobj.kobj to be really released in the module removing process (and some error code paths). [ 1844.175287] kobject: 'holders' (ffff88007c1f1600): kobject_release, parent ffffffffa01600d0 (delayed) [ 1844.178991] kobject: 'notes' (ffff8800370b2a00): kobject_release, parent ffffffffa01600d0 (delayed) [ 1845.180118] kobject: 'holders' (ffff88007c1f1600): kobject_cleanup, parent ffffffffa01600d0 [ 1845.182130] kobject: 'holders' (ffff88007c1f1600): auto cleanup kobject_del [ 1845.184120] BUG: unable to handle kernel paging request at ffffffffa01601d0 [ 1845.185026] IP: [<ffffffff812cda81>] kobject_put+0x11/0x60 [ 1845.185026] PGD 1a13067 PUD 1a14063 PMD 7bd30067 PTE 0 [ 1845.185026] Oops: 0000 [#1] PREEMPT [ 1845.185026] Modules linked in: xfs libcrc32c [last unloaded: kprobe_example] [ 1845.185026] CPU: 0 PID: 18 Comm: kworker/0:1 Tainted: G O 3.11.0-rc6-next-20130819+ #1 [ 1845.185026] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 [ 1845.185026] Workqueue: events kobject_delayed_cleanup [ 1845.185026] task: ffff88007ca51f00 ti: ffff88007ca5c000 task.ti: ffff88007ca5c000 [ 1845.185026] RIP: 0010:[<ffffffff812cda81>] [<ffffffff812cda81>] kobject_put+0x11/0x60 [ 1845.185026] RSP: 0018:ffff88007ca5dd08 EFLAGS: 00010282 [ 1845.185026] RAX: 0000000000002000 RBX: ffffffffa01600d0 RCX: ffffffff8177d638 [ 1845.185026] RDX: ffff88007ca5dc18 RSI: 0000000000000000 RDI: ffffffffa01600d0 [ 1845.185026] RBP: ffff88007ca5dd18 R08: ffffffff824e9810 R09: ffffffffffffffff [ 1845.185026] R10: ffff8800ffffffff R11: dead4ead00000001 R12: ffffffff81a95040 [ 1845.185026] R13: ffff88007b27a960 R14: ffff88007c1f1600 R15: 0000000000000000 [ 1845.185026] FS: 0000000000000000(0000) GS:ffffffff81a23000(0000) knlGS:0000000000000000 [ 1845.185026] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1845.185026] CR2: ffffffffa01601d0 CR3: 0000000037207000 CR4: 00000000000006b0 [ 1845.185026] Stack: [ 1845.185026] ffff88007c1f1600 ffff88007c1f1600 ffff88007ca5dd38 ffffffff812cdb7e [ 1845.185026] 0000000000000000 ffff88007c1f1640 ffff88007ca5dd68 ffffffff812cdbfe [ 1845.185026] ffff88007c974800 ffff88007c1f1640 ffff88007ff61a00 0000000000000000 [ 1845.185026] Call Trace: [ 1845.185026] [<ffffffff812cdb7e>] kobject_del+0x2e/0x40 [ 1845.185026] [<ffffffff812cdbfe>] kobject_delayed_cleanup+0x6e/0x1d0 [ 1845.185026] [<ffffffff81063a45>] process_one_work+0x1e5/0x670 [ 1845.185026] [<ffffffff810639e3>] ? process_one_work+0x183/0x670 [ 1845.185026] [<ffffffff810642b3>] worker_thread+0x113/0x370 [ 1845.185026] [<ffffffff810641a0>] ? rescuer_thread+0x290/0x290 [ 1845.185026] [<ffffffff8106bfba>] kthread+0xda/0xe0 [ 1845.185026] [<ffffffff814ff0f0>] ? _raw_spin_unlock_irq+0x30/0x60 [ 1845.185026] [<ffffffff8106bee0>] ? kthread_create_on_node+0x130/0x130 [ 1845.185026] [<ffffffff8150751a>] ret_from_fork+0x7a/0xb0 [ 1845.185026] [<ffffffff8106bee0>] ? kthread_create_on_node+0x130/0x130 [ 1845.185026] Code: 81 48 c7 c7 28 95 ad 81 31 c0 e8 9b da 01 00 e9 4f ff ff ff 66 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 48 85 ff 74 1d <f6> 87 00 01 00 00 01 74 1e 48 8d 7b 38 83 6b 38 01 0f 94 c0 84 [ 1845.185026] RIP [<ffffffff812cda81>] kobject_put+0x11/0x60 [ 1845.185026] RSP <ffff88007ca5dd08> [ 1845.185026] CR2: ffffffffa01601d0 [ 1845.185026] ---[ end trace 49a70afd109f5653 ]--- Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-08-20kernel/params.c: use scnprintf() instead of sprintf()Chen Gang1-3/+4
For some strings (e.g. version string), they are permitted to be larger than PAGE_SIZE (although meaningless), so recommend to use scnprintf() instead of sprintf(). Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 07:14:57 +0000