47889798da
No functional change. This patch migrates module version support out of core code into kernel/module/version.c. In addition simple code refactoring to make this possible. Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
110 lines
2.6 KiB
C
110 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Module version support
|
|
*
|
|
* Copyright (C) 2008 Rusty Russell
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/string.h>
|
|
#include <linux/printk.h>
|
|
#include "internal.h"
|
|
|
|
static u32 resolve_rel_crc(const s32 *crc)
|
|
{
|
|
return *(u32 *)((void *)crc + *crc);
|
|
}
|
|
|
|
int check_version(const struct load_info *info,
|
|
const char *symname,
|
|
struct module *mod,
|
|
const s32 *crc)
|
|
{
|
|
Elf_Shdr *sechdrs = info->sechdrs;
|
|
unsigned int versindex = info->index.vers;
|
|
unsigned int i, num_versions;
|
|
struct modversion_info *versions;
|
|
|
|
/* Exporting module didn't supply crcs? OK, we're already tainted. */
|
|
if (!crc)
|
|
return 1;
|
|
|
|
/* No versions at all? modprobe --force does this. */
|
|
if (versindex == 0)
|
|
return try_to_force_load(mod, symname) == 0;
|
|
|
|
versions = (void *)sechdrs[versindex].sh_addr;
|
|
num_versions = sechdrs[versindex].sh_size
|
|
/ sizeof(struct modversion_info);
|
|
|
|
for (i = 0; i < num_versions; i++) {
|
|
u32 crcval;
|
|
|
|
if (strcmp(versions[i].name, symname) != 0)
|
|
continue;
|
|
|
|
if (IS_ENABLED(CONFIG_MODULE_REL_CRCS))
|
|
crcval = resolve_rel_crc(crc);
|
|
else
|
|
crcval = *crc;
|
|
if (versions[i].crc == crcval)
|
|
return 1;
|
|
pr_debug("Found checksum %X vs module %lX\n",
|
|
crcval, versions[i].crc);
|
|
goto bad_version;
|
|
}
|
|
|
|
/* Broken toolchain. Warn once, then let it go.. */
|
|
pr_warn_once("%s: no symbol version for %s\n", info->name, symname);
|
|
return 1;
|
|
|
|
bad_version:
|
|
pr_warn("%s: disagrees about version of symbol %s\n", info->name, symname);
|
|
return 0;
|
|
}
|
|
|
|
int check_modstruct_version(const struct load_info *info,
|
|
struct module *mod)
|
|
{
|
|
struct find_symbol_arg fsa = {
|
|
.name = "module_layout",
|
|
.gplok = true,
|
|
};
|
|
|
|
/*
|
|
* Since this should be found in kernel (which can't be removed), no
|
|
* locking is necessary -- use preempt_disable() to placate lockdep.
|
|
*/
|
|
preempt_disable();
|
|
if (!find_symbol(&fsa)) {
|
|
preempt_enable();
|
|
BUG();
|
|
}
|
|
preempt_enable();
|
|
return check_version(info, "module_layout", mod, fsa.crc);
|
|
}
|
|
|
|
/* First part is kernel version, which we ignore if module has crcs. */
|
|
int same_magic(const char *amagic, const char *bmagic,
|
|
bool has_crcs)
|
|
{
|
|
if (has_crcs) {
|
|
amagic += strcspn(amagic, " ");
|
|
bmagic += strcspn(bmagic, " ");
|
|
}
|
|
return strcmp(amagic, bmagic) == 0;
|
|
}
|
|
|
|
/*
|
|
* Generate the signature for all relevant module structures here.
|
|
* If these change, we don't want to try to parse the module.
|
|
*/
|
|
void module_layout(struct module *mod,
|
|
struct modversion_info *ver,
|
|
struct kernel_param *kp,
|
|
struct kernel_symbol *ks,
|
|
struct tracepoint * const *tp)
|
|
{
|
|
}
|
|
EXPORT_SYMBOL(module_layout);
|