From 8db5da0b8618df79eceea99672e205d4a2a6309e Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Sun, 27 Jan 2019 19:03:45 -0500 Subject: x86/ima: require signed kernel modules Have the IMA architecture specific policy require signed kernel modules on systems with secure boot mode enabled; and coordinate the different signature verification methods, so only one signature is required. Requiring appended kernel module signatures may be configured, enabled on the boot command line, or with this patch enabled in secure boot mode. This patch defines set_module_sig_enforced(). To coordinate between appended kernel module signatures and IMA signatures, only define an IMA MODULE_CHECK policy rule if CONFIG_MODULE_SIG is not enabled. A custom IMA policy may still define and require an IMA signature. Signed-off-by: Mimi Zohar Reviewed-by: Luis Chamberlain Acked-by: Jessica Yu --- kernel/module.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 0b9aa8ab89f0..985caa467aef 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -286,6 +286,11 @@ bool is_module_sig_enforced(void) } EXPORT_SYMBOL(is_module_sig_enforced); +void set_module_sig_enforced(void) +{ + sig_enforce = true; +} + /* Block module loading/unloading? */ int modules_disabled = 0; core_param(nomodule, modules_disabled, bint, 0); -- cgit v1.2.3 From 1c7651f43777cdd59c1aaa82c87324d3e7438c7b Mon Sep 17 00:00:00 2001 From: Eugene Loh Date: Mon, 25 Feb 2019 11:59:58 -0800 Subject: kallsyms: store type information in its own array When a module is loaded, its symbols' Elf_Sym information is stored in a symtab. Further, type information is also captured. Since Elf_Sym has no type field, historically the st_info field has been hijacked for storing type: st_info was overwritten. commit 5439c985c5a83a8419f762115afdf560ab72a452 ("module: Overwrite st_size instead of st_info") changes that practice, as its one-liner indicates. Unfortunately, this change overwrites symbol size, information that a tool like DTrace expects to find. Allocate a typetab array to store type information so that no Elf_Sym field needs to be overwritten. Fixes: 5439c985c5a8 ("module: Overwrite st_size instead of st_info") Signed-off-by: Eugene Loh Reviewed-by: Nick Alcock [jeyu: renamed typeoff -> typeoffs ] Signed-off-by: Jessica Yu --- kernel/module.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 0b9aa8ab89f0..69e52e82242a 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2647,6 +2647,8 @@ static void layout_symtab(struct module *mod, struct load_info *info) info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1); info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym); mod->core_layout.size += strtab_size; + info->core_typeoffs = mod->core_layout.size; + mod->core_layout.size += ndst * sizeof(char); mod->core_layout.size = debug_align(mod->core_layout.size); /* Put string table section at end of init part of module. */ @@ -2660,6 +2662,8 @@ static void layout_symtab(struct module *mod, struct load_info *info) __alignof__(struct mod_kallsyms)); info->mod_kallsyms_init_off = mod->init_layout.size; mod->init_layout.size += sizeof(struct mod_kallsyms); + info->init_typeoffs = mod->init_layout.size; + mod->init_layout.size += nsrc * sizeof(char); mod->init_layout.size = debug_align(mod->init_layout.size); } @@ -2683,20 +2687,23 @@ static void add_kallsyms(struct module *mod, const struct load_info *info) mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym); /* Make sure we get permanent strtab: don't use info->strtab. */ mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr; + mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs; - /* Set types up while we still have access to sections. */ - for (i = 0; i < mod->kallsyms->num_symtab; i++) - mod->kallsyms->symtab[i].st_size - = elf_type(&mod->kallsyms->symtab[i], info); - - /* Now populate the cut down core kallsyms for after init. */ + /* + * Now populate the cut down core kallsyms for after init + * and set types up while we still have access to sections. + */ mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs; mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs; + mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs; src = mod->kallsyms->symtab; for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) { + mod->kallsyms->typetab[i] = elf_type(src + i, info); if (i == 0 || is_livepatch_module(mod) || is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum, info->index.pcpu)) { + mod->core_kallsyms.typetab[ndst] = + mod->kallsyms->typetab[i]; dst[ndst] = src[i]; dst[ndst++].st_name = s - mod->core_kallsyms.strtab; s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name], @@ -4080,7 +4087,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, const Elf_Sym *sym = &kallsyms->symtab[symnum]; *value = kallsyms_symbol_value(sym); - *type = sym->st_size; + *type = kallsyms->typetab[symnum]; strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN); strlcpy(module_name, mod->name, MODULE_NAME_LEN); *exported = is_exported(name, *value, mod); -- cgit v1.2.3 From 1a59d1b8e05ea6ab45f7e18897de1ef0e6bc3da6 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 27 May 2019 08:55:05 +0200 Subject: treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 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 Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 14 +------------- 1 file changed, 1 insertion(+), 13 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 6e6712b3aaf5..80c7c09584cf 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1,20 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* Copyright (C) 2002 Richard Henderson Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. - 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 */ #include #include -- cgit v1.2.3