Contributors: 8
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Aaron Tomlin |
193 |
48.13% |
4 |
22.22% |
| Christophe Leroy |
149 |
37.16% |
6 |
33.33% |
| Song Liu |
44 |
10.97% |
1 |
5.56% |
| Rusty Russell |
9 |
2.24% |
3 |
16.67% |
| Laura Abbott |
2 |
0.50% |
1 |
5.56% |
| Ingo Molnar |
2 |
0.50% |
1 |
5.56% |
| Michael Ellerman |
1 |
0.25% |
1 |
5.56% |
| Thomas Gleixner |
1 |
0.25% |
1 |
5.56% |
| Total |
401 |
|
18 |
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Module strict rwx
*
* Copyright (C) 2015 Rusty Russell
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
#include "internal.h"
static int module_set_memory(const struct module *mod, enum mod_mem_type type,
int (*set_memory)(unsigned long start, int num_pages))
{
const struct module_memory *mod_mem = &mod->mem[type];
if (!mod_mem->base)
return 0;
set_vm_flush_reset_perms(mod_mem->base);
return set_memory((unsigned long)mod_mem->base, mod_mem->size >> PAGE_SHIFT);
}
/*
* Since some arches are moving towards PAGE_KERNEL module allocations instead
* of PAGE_KERNEL_EXEC, keep module_enable_x() independent of
* CONFIG_STRICT_MODULE_RWX because they are needed regardless of whether we
* are strict.
*/
int module_enable_text_rox(const struct module *mod)
{
for_class_mod_mem_type(type, text) {
int ret;
if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
ret = module_set_memory(mod, type, set_memory_rox);
else
ret = module_set_memory(mod, type, set_memory_x);
if (ret)
return ret;
}
return 0;
}
int module_enable_rodata_ro(const struct module *mod, bool after_init)
{
int ret;
if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX) || !rodata_enabled)
return 0;
ret = module_set_memory(mod, MOD_RODATA, set_memory_ro);
if (ret)
return ret;
ret = module_set_memory(mod, MOD_INIT_RODATA, set_memory_ro);
if (ret)
return ret;
if (after_init)
return module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro);
return 0;
}
int module_enable_data_nx(const struct module *mod)
{
if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return 0;
for_class_mod_mem_type(type, data) {
int ret = module_set_memory(mod, type, set_memory_nx);
if (ret)
return ret;
}
return 0;
}
int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
char *secstrings, struct module *mod)
{
const unsigned long shf_wx = SHF_WRITE | SHF_EXECINSTR;
int i;
if (!IS_ENABLED(CONFIG_STRICT_MODULE_RWX))
return 0;
for (i = 0; i < hdr->e_shnum; i++) {
if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) {
pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n",
mod->name, secstrings + sechdrs[i].sh_name, i);
return -ENOEXEC;
}
}
return 0;
}