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Based on 2 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 see http www gnu org licenses 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 [based] [from] [clk] [highbank] [c] you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 355 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
71 lines
1.3 KiB
C
71 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* livepatch-sample.c - Kernel Live Patching Sample Module
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*
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* Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/livepatch.h>
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/*
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* This (dumb) live patch overrides the function that prints the
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* kernel boot cmdline when /proc/cmdline is read.
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*
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* Example:
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*
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* $ cat /proc/cmdline
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* <your cmdline>
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*
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* $ insmod livepatch-sample.ko
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* $ cat /proc/cmdline
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* this has been live patched
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*
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* $ echo 0 > /sys/kernel/livepatch/livepatch_sample/enabled
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* $ cat /proc/cmdline
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* <your cmdline>
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*/
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#include <linux/seq_file.h>
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static int livepatch_cmdline_proc_show(struct seq_file *m, void *v)
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{
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seq_printf(m, "%s\n", "this has been live patched");
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return 0;
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}
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static struct klp_func funcs[] = {
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{
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.old_name = "cmdline_proc_show",
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.new_func = livepatch_cmdline_proc_show,
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}, { }
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};
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static struct klp_object objs[] = {
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{
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/* name being NULL means vmlinux */
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.funcs = funcs,
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}, { }
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};
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static struct klp_patch patch = {
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.mod = THIS_MODULE,
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.objs = objs,
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};
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static int livepatch_init(void)
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{
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return klp_enable_patch(&patch);
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}
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static void livepatch_exit(void)
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{
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}
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module_init(livepatch_init);
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module_exit(livepatch_exit);
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MODULE_LICENSE("GPL");
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MODULE_INFO(livepatch, "Y");
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