Architecture-specific and reloc code no longer needed, symbol resolution and relocation work will be offloaded to module loader. Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx> --- arch/x86/kernel/Makefile | 1 - arch/x86/kernel/livepatch.c | 90 --------------------------------------------- kernel/livepatch/core.c | 72 ------------------------------------ 3 files changed, 163 deletions(-) delete mode 100644 arch/x86/kernel/livepatch.c diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index cdb1b70..fae4c4e 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -67,7 +67,6 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-y += apic/ obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o -obj-$(CONFIG_LIVEPATCH) += livepatch.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o obj-$(CONFIG_X86_TSC) += trace_clock.o diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c deleted file mode 100644 index ff3c310..0000000 --- a/arch/x86/kernel/livepatch.c +++ /dev/null @@ -1,90 +0,0 @@ -/* - * livepatch.c - x86-specific Kernel Live Patching Core - * - * Copyright (C) 2014 Seth Jennings <sjenning@xxxxxxxxxx> - * Copyright (C) 2014 SUSE - * - * 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/>. - */ - -#include <linux/module.h> -#include <linux/uaccess.h> -#include <asm/cacheflush.h> -#include <asm/page_types.h> -#include <asm/elf.h> -#include <asm/livepatch.h> - -/** - * klp_write_module_reloc() - write a relocation in a module - * @mod: module in which the section to be modified is found - * @type: ELF relocation type (see asm/elf.h) - * @loc: address that the relocation should be written to - * @value: relocation value (sym address + addend) - * - * This function writes a relocation to the specified location for - * a particular module. - */ -int klp_write_module_reloc(struct module *mod, unsigned long type, - unsigned long loc, unsigned long value) -{ - int ret, numpages, size = 4; - bool readonly; - unsigned long val; - unsigned long core = (unsigned long)mod->module_core; - unsigned long core_ro_size = mod->core_ro_size; - unsigned long core_size = mod->core_size; - - switch (type) { - case R_X86_64_NONE: - return 0; - case R_X86_64_64: - val = value; - size = 8; - break; - case R_X86_64_32: - val = (u32)value; - break; - case R_X86_64_32S: - val = (s32)value; - break; - case R_X86_64_PC32: - val = (u32)(value - loc); - break; - default: - /* unsupported relocation type */ - return -EINVAL; - } - - if (loc < core || loc >= core + core_size) - /* loc does not point to any symbol inside the module */ - return -EINVAL; - - if (loc < core + core_ro_size) - readonly = true; - else - readonly = false; - - /* determine if the relocation spans a page boundary */ - numpages = ((loc & PAGE_MASK) == ((loc + size) & PAGE_MASK)) ? 1 : 2; - - if (readonly) - set_memory_rw(loc & PAGE_MASK, numpages); - - ret = probe_kernel_write((void *)loc, &val, size); - - if (readonly) - set_memory_ro(loc & PAGE_MASK, numpages); - - return ret; -} diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 7c1cd5c..7a786e7 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -331,72 +331,6 @@ static int klp_find_verify_func_addr(struct klp_object *obj, return ret; } -/* - * external symbols are located outside the parent object (where the parent - * object is either vmlinux or the kmod being patched). - */ -static int klp_find_external_symbol(struct module *pmod, const char *name, - unsigned long *addr) -{ - const struct kernel_symbol *sym; - - /* first, check if it's an exported symbol */ - preempt_disable(); - sym = find_symbol(name, NULL, NULL, true, true); - if (sym) { - *addr = sym->value; - preempt_enable(); - return 0; - } - preempt_enable(); - - /* otherwise check if it's in another .o within the patch module */ - return klp_find_object_symbol(pmod->name, name, addr); -} - -static int klp_write_object_relocations(struct module *pmod, - struct klp_object *obj) -{ - int ret; - struct klp_reloc *reloc; - - if (WARN_ON(!klp_is_object_loaded(obj))) - return -EINVAL; - - if (WARN_ON(!obj->relocs)) - return -EINVAL; - - for (reloc = obj->relocs; reloc->name; reloc++) { - if (!klp_is_module(obj)) { - ret = klp_verify_vmlinux_symbol(reloc->name, - reloc->val); - if (ret) - return ret; - } else { - /* module, reloc->val needs to be discovered */ - if (reloc->external) - ret = klp_find_external_symbol(pmod, - reloc->name, - &reloc->val); - else - ret = klp_find_object_symbol(obj->mod->name, - reloc->name, - &reloc->val); - if (ret) - return ret; - } - ret = klp_write_module_reloc(pmod, reloc->type, reloc->loc, - reloc->val + reloc->addend); - if (ret) { - pr_err("relocation failed for symbol '%s' at 0x%016lx (%d)\n", - reloc->name, reloc->val, ret); - return ret; - } - } - - return 0; -} - static void notrace klp_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *fops, @@ -837,12 +771,6 @@ static int klp_init_object_loaded(struct klp_patch *patch, struct klp_func *func; int ret; - if (obj->relocs) { - ret = klp_write_object_relocations(patch->mod, obj); - if (ret) - return ret; - } - for (func = obj->funcs; func->old_name; func++) { ret = klp_find_verify_func_addr(obj, func); if (ret) -- 2.4.2 -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
