Merge tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull module updates from Jessica Yu:

 - Retire EXPORT_UNUSED_SYMBOL() and EXPORT_SYMBOL_GPL_FUTURE(). These
   export types were introduced between 2006 - 2008. All the of the
   unused symbols have been long removed and gpl future symbols were
   converted to gpl quite a long time ago, and I don't believe these
   export types have been used ever since. So, I think it should be safe
   to retire those export types now (Christoph Hellwig)

 - Refactor and clean up some aged code cruft in the module loader
   (Christoph Hellwig)

 - Build {,module_}kallsyms_on_each_symbol only when livepatching is
   enabled, as it is the only caller (Christoph Hellwig)

 - Unexport find_module() and module_mutex and fix the last module
   callers to not rely on these anymore. Make module_mutex internal to
   the module loader (Christoph Hellwig)

 - Harden ELF checks on module load and validate ELF structures before
   checking the module signature (Frank van der Linden)

 - Fix undefined symbol warning for clang (Fangrui Song)

 - Fix smatch warning (Dan Carpenter)

* tag 'modules-for-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: potential uninitialized return in module_kallsyms_on_each_symbol()
  module: remove EXPORT_UNUSED_SYMBOL*
  module: remove EXPORT_SYMBOL_GPL_FUTURE
  module: move struct symsearch to module.c
  module: pass struct find_symbol_args to find_symbol
  module: merge each_symbol_section into find_symbol
  module: remove each_symbol_in_section
  module: mark module_mutex static
  kallsyms: only build {,module_}kallsyms_on_each_symbol when required
  kallsyms: refactor {,module_}kallsyms_on_each_symbol
  module: use RCU to synchronize find_module
  module: unexport find_module and module_mutex
  drm: remove drm_fb_helper_modinit
  powerpc/powernv: remove get_cxl_module
  module: harden ELF info handling
  module: Ignore _GLOBAL_OFFSET_TABLE_ when warning for undefined symbols
This commit is contained in:
Linus Torvalds
2021-02-23 10:15:33 -08:00
35 changed files with 282 additions and 511 deletions

View File

@@ -177,6 +177,11 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}
#ifdef CONFIG_LIVEPATCH
/*
* Iterate over all symbols in vmlinux. For symbols from modules use
* module_kallsyms_on_each_symbol instead.
*/
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data)
@@ -192,8 +197,9 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
if (ret != 0)
return ret;
}
return module_kallsyms_on_each_symbol(fn, data);
return 0;
}
#endif /* CONFIG_LIVEPATCH */
static unsigned long get_symbol_pos(unsigned long addr,
unsigned long *symbolsize,

View File

@@ -19,6 +19,7 @@
#include <linux/moduleloader.h>
#include <linux/completion.h>
#include <linux/memory.h>
#include <linux/rcupdate.h>
#include <asm/cacheflush.h>
#include "core.h"
#include "patch.h"
@@ -57,7 +58,7 @@ static void klp_find_object_module(struct klp_object *obj)
if (!klp_is_module(obj))
return;
mutex_lock(&module_mutex);
rcu_read_lock_sched();
/*
* We do not want to block removal of patched modules and therefore
* we do not take a reference here. The patches are removed by
@@ -74,7 +75,7 @@ static void klp_find_object_module(struct klp_object *obj)
if (mod && mod->klp_alive)
obj->mod = mod;
mutex_unlock(&module_mutex);
rcu_read_unlock_sched();
}
static bool klp_initialized(void)
@@ -163,12 +164,10 @@ static int klp_find_object_symbol(const char *objname, const char *name,
.pos = sympos,
};
mutex_lock(&module_mutex);
if (objname)
module_kallsyms_on_each_symbol(klp_find_callback, &args);
else
kallsyms_on_each_symbol(klp_find_callback, &args);
mutex_unlock(&module_mutex);
/*
* Ensure an address was found. If sympos is 0, ensure symbol is unique;

View File

@@ -87,8 +87,7 @@
* 3) module_addr_min/module_addr_max.
* (delete and add uses RCU list operations).
*/
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
static DEFINE_MUTEX(module_mutex);
static LIST_HEAD(modules);
/* Work queue for freeing init sections in success case */
@@ -256,11 +255,6 @@ static void mod_update_bounds(struct module *mod)
struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
#endif /* CONFIG_KGDB_KDB */
static void module_assert_mutex(void)
{
lockdep_assert_held(&module_mutex);
}
static void module_assert_mutex_or_preempt(void)
{
#ifdef CONFIG_LOCKDEP
@@ -414,19 +408,8 @@ extern const struct kernel_symbol __start___ksymtab[];
extern const struct kernel_symbol __stop___ksymtab[];
extern const struct kernel_symbol __start___ksymtab_gpl[];
extern const struct kernel_symbol __stop___ksymtab_gpl[];
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
extern const s32 __start___kcrctab[];
extern const s32 __start___kcrctab_gpl[];
extern const s32 __start___kcrctab_gpl_future[];
#ifdef CONFIG_UNUSED_SYMBOLS
extern const struct kernel_symbol __start___ksymtab_unused[];
extern const struct kernel_symbol __stop___ksymtab_unused[];
extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
extern const s32 __start___kcrctab_unused[];
extern const s32 __start___kcrctab_unused_gpl[];
#endif
#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
@@ -434,87 +417,14 @@ extern const s32 __start___kcrctab_unused_gpl[];
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif
static bool each_symbol_in_section(const struct symsearch *arr,
unsigned int arrsize,
struct module *owner,
bool (*fn)(const struct symsearch *syms,
struct module *owner,
void *data),
void *data)
{
unsigned int j;
for (j = 0; j < arrsize; j++) {
if (fn(&arr[j], owner, data))
return true;
}
return false;
}
/* Returns true as soon as fn returns true, otherwise false. */
static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
struct module *owner,
void *data),
void *data)
{
struct module *mod;
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
NOT_GPL_ONLY, false },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
__start___kcrctab_gpl,
GPL_ONLY, false },
{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
__start___kcrctab_gpl_future,
WILL_BE_GPL_ONLY, false },
#ifdef CONFIG_UNUSED_SYMBOLS
{ __start___ksymtab_unused, __stop___ksymtab_unused,
__start___kcrctab_unused,
NOT_GPL_ONLY, true },
{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
__start___kcrctab_unused_gpl,
GPL_ONLY, true },
#endif
};
module_assert_mutex_or_preempt();
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
return true;
list_for_each_entry_rcu(mod, &modules, list,
lockdep_is_held(&module_mutex)) {
struct symsearch arr[] = {
{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
NOT_GPL_ONLY, false },
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
mod->gpl_crcs,
GPL_ONLY, false },
{ mod->gpl_future_syms,
mod->gpl_future_syms + mod->num_gpl_future_syms,
mod->gpl_future_crcs,
WILL_BE_GPL_ONLY, false },
#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms,
mod->unused_syms + mod->num_unused_syms,
mod->unused_crcs,
NOT_GPL_ONLY, true },
{ mod->unused_gpl_syms,
mod->unused_gpl_syms + mod->num_unused_gpl_syms,
mod->unused_gpl_crcs,
GPL_ONLY, true },
#endif
};
if (mod->state == MODULE_STATE_UNFORMED)
continue;
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
return true;
}
return false;
}
struct symsearch {
const struct kernel_symbol *start, *stop;
const s32 *crcs;
enum mod_license {
NOT_GPL_ONLY,
GPL_ONLY,
} license;
};
struct find_symbol_arg {
/* Input */
@@ -535,28 +445,8 @@ static bool check_exported_symbol(const struct symsearch *syms,
{
struct find_symbol_arg *fsa = data;
if (!fsa->gplok) {
if (syms->license == GPL_ONLY)
return false;
if (syms->license == WILL_BE_GPL_ONLY && fsa->warn) {
pr_warn("Symbol %s is being used by a non-GPL module, "
"which will not be allowed in the future\n",
fsa->name);
}
}
#ifdef CONFIG_UNUSED_SYMBOLS
if (syms->unused && fsa->warn) {
pr_warn("Symbol %s is marked as UNUSED, however this module is "
"using it.\n", fsa->name);
pr_warn("This symbol will go away in the future.\n");
pr_warn("Please evaluate if this is the right api to use and "
"if it really is, submit a report to the linux kernel "
"mailing list together with submitting your code for "
"inclusion.\n");
}
#endif
if (!fsa->gplok && syms->license == GPL_ONLY)
return false;
fsa->owner = owner;
fsa->crc = symversion(syms->crcs, symnum);
fsa->sym = &syms->start[symnum];
@@ -619,31 +509,44 @@ static bool find_exported_symbol_in_section(const struct symsearch *syms,
* Find an exported symbol and return it, along with, (optional) crc and
* (optional) module which owns it. Needs preempt disabled or module_mutex.
*/
static const struct kernel_symbol *find_symbol(const char *name,
struct module **owner,
const s32 **crc,
enum mod_license *license,
bool gplok,
bool warn)
static bool find_symbol(struct find_symbol_arg *fsa)
{
struct find_symbol_arg fsa;
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
NOT_GPL_ONLY },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
__start___kcrctab_gpl,
GPL_ONLY },
};
struct module *mod;
unsigned int i;
fsa.name = name;
fsa.gplok = gplok;
fsa.warn = warn;
module_assert_mutex_or_preempt();
if (each_symbol_section(find_exported_symbol_in_section, &fsa)) {
if (owner)
*owner = fsa.owner;
if (crc)
*crc = fsa.crc;
if (license)
*license = fsa.license;
return fsa.sym;
for (i = 0; i < ARRAY_SIZE(arr); i++)
if (find_exported_symbol_in_section(&arr[i], NULL, fsa))
return true;
list_for_each_entry_rcu(mod, &modules, list,
lockdep_is_held(&module_mutex)) {
struct symsearch arr[] = {
{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
NOT_GPL_ONLY },
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
mod->gpl_crcs,
GPL_ONLY },
};
if (mod->state == MODULE_STATE_UNFORMED)
continue;
for (i = 0; i < ARRAY_SIZE(arr); i++)
if (find_exported_symbol_in_section(&arr[i], mod, fsa))
return true;
}
pr_debug("Failed to find symbol %s\n", name);
return NULL;
pr_debug("Failed to find symbol %s\n", fsa->name);
return false;
}
/*
@@ -669,10 +572,8 @@ static struct module *find_module_all(const char *name, size_t len,
struct module *find_module(const char *name)
{
module_assert_mutex();
return find_module_all(name, strlen(name), false);
}
EXPORT_SYMBOL_GPL(find_module);
#ifdef CONFIG_SMP
@@ -1107,12 +1008,15 @@ static inline void print_unload_info(struct seq_file *m, struct module *mod)
void __symbol_put(const char *symbol)
{
struct module *owner;
struct find_symbol_arg fsa = {
.name = symbol,
.gplok = true,
};
preempt_disable();
if (!find_symbol(symbol, &owner, NULL, NULL, true, false))
if (!find_symbol(&fsa))
BUG();
module_put(owner);
module_put(fsa.owner);
preempt_enable();
}
EXPORT_SYMBOL(__symbol_put);
@@ -1381,19 +1285,22 @@ bad_version:
static inline int check_modstruct_version(const struct load_info *info,
struct module *mod)
{
const s32 *crc;
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("module_layout", NULL, &crc, NULL, true, false)) {
if (!find_symbol(&fsa)) {
preempt_enable();
BUG();
}
preempt_enable();
return check_version(info, "module_layout", mod, crc);
return check_version(info, "module_layout", mod, fsa.crc);
}
/* First part is kernel version, which we ignore if module has crcs. */
@@ -1487,10 +1394,11 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
const char *name,
char ownername[])
{
struct module *owner;
const struct kernel_symbol *sym;
const s32 *crc;
enum mod_license license;
struct find_symbol_arg fsa = {
.name = name,
.gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
.warn = true,
};
int err;
/*
@@ -1500,42 +1408,40 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
*/
sched_annotate_sleep();
mutex_lock(&module_mutex);
sym = find_symbol(name, &owner, &crc, &license,
!(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
if (!sym)
if (!find_symbol(&fsa))
goto unlock;
if (license == GPL_ONLY)
if (fsa.license == GPL_ONLY)
mod->using_gplonly_symbols = true;
if (!inherit_taint(mod, owner)) {
sym = NULL;
if (!inherit_taint(mod, fsa.owner)) {
fsa.sym = NULL;
goto getname;
}
if (!check_version(info, name, mod, crc)) {
sym = ERR_PTR(-EINVAL);
if (!check_version(info, name, mod, fsa.crc)) {
fsa.sym = ERR_PTR(-EINVAL);
goto getname;
}
err = verify_namespace_is_imported(info, sym, mod);
err = verify_namespace_is_imported(info, fsa.sym, mod);
if (err) {
sym = ERR_PTR(err);
fsa.sym = ERR_PTR(err);
goto getname;
}
err = ref_module(mod, owner);
err = ref_module(mod, fsa.owner);
if (err) {
sym = ERR_PTR(err);
fsa.sym = ERR_PTR(err);
goto getname;
}
getname:
/* We must make copy under the lock if we failed to get ref. */
strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
unlock:
mutex_unlock(&module_mutex);
return sym;
return fsa.sym;
}
static const struct kernel_symbol *
@@ -2296,16 +2202,19 @@ static void free_module(struct module *mod)
void *__symbol_get(const char *symbol)
{
struct module *owner;
const struct kernel_symbol *sym;
struct find_symbol_arg fsa = {
.name = symbol,
.gplok = true,
.warn = true,
};
preempt_disable();
sym = find_symbol(symbol, &owner, NULL, NULL, true, true);
if (sym && strong_try_module_get(owner))
sym = NULL;
if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) {
preempt_enable();
return NULL;
}
preempt_enable();
return sym ? (void *)kernel_symbol_value(sym) : NULL;
return (void *)kernel_symbol_value(fsa.sym);
}
EXPORT_SYMBOL_GPL(__symbol_get);
@@ -2318,7 +2227,6 @@ EXPORT_SYMBOL_GPL(__symbol_get);
static int verify_exported_symbols(struct module *mod)
{
unsigned int i;
struct module *owner;
const struct kernel_symbol *s;
struct {
const struct kernel_symbol *sym;
@@ -2326,21 +2234,19 @@ static int verify_exported_symbols(struct module *mod)
} arr[] = {
{ mod->syms, mod->num_syms },
{ mod->gpl_syms, mod->num_gpl_syms },
{ mod->gpl_future_syms, mod->num_gpl_future_syms },
#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms, mod->num_unused_syms },
{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
#endif
};
for (i = 0; i < ARRAY_SIZE(arr); i++) {
for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
if (find_symbol(kernel_symbol_name(s), &owner, NULL,
NULL, true, false)) {
struct find_symbol_arg fsa = {
.name = kernel_symbol_name(s),
.gplok = true,
};
if (find_symbol(&fsa)) {
pr_err("%s: exports duplicate symbol %s"
" (owned by %s)\n",
mod->name, kernel_symbol_name(s),
module_name(owner));
module_name(fsa.owner));
return -ENOEXEC;
}
}
@@ -2348,6 +2254,21 @@ static int verify_exported_symbols(struct module *mod)
return 0;
}
static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
{
/*
* On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
* before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
* i386 has a similar problem but may not deserve a fix.
*
* If we ever have to ignore many symbols, consider refactoring the code to
* only warn if referenced by a relocation.
*/
if (emachine == EM_386 || emachine == EM_X86_64)
return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
return false;
}
/* Change all symbols so that st_value encodes the pointer directly. */
static int simplify_symbols(struct module *mod, const struct load_info *info)
{
@@ -2395,8 +2316,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info)
break;
}
/* Ok if weak. */
if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
/* Ok if weak or ignored. */
if (!ksym &&
(ELF_ST_BIND(sym[i].st_info) == STB_WEAK ||
ignore_undef_symbol(info->hdr->e_machine, name)))
break;
ret = PTR_ERR(ksym) ?: -ENOENT;
@@ -2964,7 +2887,7 @@ static int module_sig_check(struct load_info *info, int flags)
}
if (is_module_sig_enforced()) {
pr_notice("%s: loading of %s is rejected\n", info->name, reason);
pr_notice("Loading of %s is rejected\n", reason);
return -EKEYREJECTED;
}
@@ -2977,9 +2900,33 @@ static int module_sig_check(struct load_info *info, int flags)
}
#endif /* !CONFIG_MODULE_SIG */
/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
static int elf_header_check(struct load_info *info)
static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr)
{
unsigned long secend;
/*
* Check for both overflow and offset/size being
* too large.
*/
secend = shdr->sh_offset + shdr->sh_size;
if (secend < shdr->sh_offset || secend > info->len)
return -ENOEXEC;
return 0;
}
/*
* Sanity checks against invalid binaries, wrong arch, weird elf version.
*
* Also do basic validity checks against section offsets and sizes, the
* section name string table, and the indices used for it (sh_name).
*/
static int elf_validity_check(struct load_info *info)
{
unsigned int i;
Elf_Shdr *shdr, *strhdr;
int err;
if (info->len < sizeof(*(info->hdr)))
return -ENOEXEC;
@@ -2989,11 +2936,78 @@ static int elf_header_check(struct load_info *info)
|| info->hdr->e_shentsize != sizeof(Elf_Shdr))
return -ENOEXEC;
/*
* e_shnum is 16 bits, and sizeof(Elf_Shdr) is
* known and small. So e_shnum * sizeof(Elf_Shdr)
* will not overflow unsigned long on any platform.
*/
if (info->hdr->e_shoff >= info->len
|| (info->hdr->e_shnum * sizeof(Elf_Shdr) >
info->len - info->hdr->e_shoff))
return -ENOEXEC;
info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
/*
* Verify if the section name table index is valid.
*/
if (info->hdr->e_shstrndx == SHN_UNDEF
|| info->hdr->e_shstrndx >= info->hdr->e_shnum)
return -ENOEXEC;
strhdr = &info->sechdrs[info->hdr->e_shstrndx];
err = validate_section_offset(info, strhdr);
if (err < 0)
return err;
/*
* The section name table must be NUL-terminated, as required
* by the spec. This makes strcmp and pr_* calls that access
* strings in the section safe.
*/
info->secstrings = (void *)info->hdr + strhdr->sh_offset;
if (info->secstrings[strhdr->sh_size - 1] != '\0')
return -ENOEXEC;
/*
* The code assumes that section 0 has a length of zero and
* an addr of zero, so check for it.
*/
if (info->sechdrs[0].sh_type != SHT_NULL
|| info->sechdrs[0].sh_size != 0
|| info->sechdrs[0].sh_addr != 0)
return -ENOEXEC;
for (i = 1; i < info->hdr->e_shnum; i++) {
shdr = &info->sechdrs[i];
switch (shdr->sh_type) {
case SHT_NULL:
case SHT_NOBITS:
continue;
case SHT_SYMTAB:
if (shdr->sh_link == SHN_UNDEF
|| shdr->sh_link >= info->hdr->e_shnum)
return -ENOEXEC;
fallthrough;
default:
err = validate_section_offset(info, shdr);
if (err < 0) {
pr_err("Invalid ELF section in module (section %u type %u)\n",
i, shdr->sh_type);
return err;
}
if (shdr->sh_flags & SHF_ALLOC) {
if (shdr->sh_name >= strhdr->sh_size) {
pr_err("Invalid ELF section name in module (section %u type %u)\n",
i, shdr->sh_type);
return -ENOEXEC;
}
}
break;
}
}
return 0;
}
@@ -3095,11 +3109,6 @@ static int rewrite_section_headers(struct load_info *info, int flags)
for (i = 1; i < info->hdr->e_shnum; i++) {
Elf_Shdr *shdr = &info->sechdrs[i];
if (shdr->sh_type != SHT_NOBITS
&& info->len < shdr->sh_offset + shdr->sh_size) {
pr_err("Module len %lu truncated\n", info->len);
return -ENOEXEC;
}
/*
* Mark all sections sh_addr with their address in the
@@ -3133,11 +3142,6 @@ static int setup_load_info(struct load_info *info, int flags)
{
unsigned int i;
/* Set up the convenience variables */
info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
info->secstrings = (void *)info->hdr
+ info->sechdrs[info->hdr->e_shstrndx].sh_offset;
/* Try to find a name early so we can log errors with a module name */
info->index.info = find_sec(info, ".modinfo");
if (info->index.info)
@@ -3241,22 +3245,7 @@ static int find_module_sections(struct module *mod, struct load_info *info)
sizeof(*mod->gpl_syms),
&mod->num_gpl_syms);
mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
mod->gpl_future_syms = section_objs(info,
"__ksymtab_gpl_future",
sizeof(*mod->gpl_future_syms),
&mod->num_gpl_future_syms);
mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
#ifdef CONFIG_UNUSED_SYMBOLS
mod->unused_syms = section_objs(info, "__ksymtab_unused",
sizeof(*mod->unused_syms),
&mod->num_unused_syms);
mod->unused_crcs = section_addr(info, "__kcrctab_unused");
mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
sizeof(*mod->unused_gpl_syms),
&mod->num_unused_gpl_syms);
mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
#endif
#ifdef CONFIG_CONSTRUCTORS
mod->ctors = section_objs(info, ".ctors",
sizeof(*mod->ctors), &mod->num_ctors);
@@ -3437,14 +3426,8 @@ static int check_module_license_and_versions(struct module *mod)
pr_warn("%s: module license taints kernel.\n", mod->name);
#ifdef CONFIG_MODVERSIONS
if ((mod->num_syms && !mod->crcs)
|| (mod->num_gpl_syms && !mod->gpl_crcs)
|| (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
#ifdef CONFIG_UNUSED_SYMBOLS
|| (mod->num_unused_syms && !mod->unused_crcs)
|| (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
#endif
) {
if ((mod->num_syms && !mod->crcs) ||
(mod->num_gpl_syms && !mod->gpl_crcs)) {
return try_to_force_load(mod,
"no versions for exported symbols");
}
@@ -3894,26 +3877,50 @@ static int load_module(struct load_info *info, const char __user *uargs,
long err = 0;
char *after_dashes;
err = elf_header_check(info);
/*
* Do the signature check (if any) first. All that
* the signature check needs is info->len, it does
* not need any of the section info. That can be
* set up later. This will minimize the chances
* of a corrupt module causing problems before
* we even get to the signature check.
*
* The check will also adjust info->len by stripping
* off the sig length at the end of the module, making
* checks against info->len more correct.
*/
err = module_sig_check(info, flags);
if (err)
goto free_copy;
/*
* Do basic sanity checks against the ELF header and
* sections.
*/
err = elf_validity_check(info);
if (err) {
pr_err("Module has invalid ELF header\n");
pr_err("Module has invalid ELF structures\n");
goto free_copy;
}
/*
* Everything checks out, so set up the section info
* in the info structure.
*/
err = setup_load_info(info, flags);
if (err)
goto free_copy;
/*
* Now that we know we have the correct module name, check
* if it's blacklisted.
*/
if (blacklisted(info->name)) {
err = -EPERM;
pr_err("Module %s is blacklisted\n", info->name);
goto free_copy;
}
err = module_sig_check(info, flags);
if (err)
goto free_copy;
err = rewrite_section_headers(info, flags);
if (err)
goto free_copy;
@@ -4374,16 +4381,16 @@ unsigned long module_kallsyms_lookup_name(const char *name)
return ret;
}
#ifdef CONFIG_LIVEPATCH
int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *, unsigned long),
void *data)
{
struct module *mod;
unsigned int i;
int ret;
module_assert_mutex();
int ret = 0;
mutex_lock(&module_mutex);
list_for_each_entry(mod, &modules, list) {
/* We hold module_mutex: no need for rcu_dereference_sched */
struct mod_kallsyms *kallsyms = mod->kallsyms;
@@ -4399,11 +4406,13 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
ret = fn(data, kallsyms_symbol_name(kallsyms, i),
mod, kallsyms_symbol_value(sym));
if (ret != 0)
return ret;
break;
}
}
return 0;
mutex_unlock(&module_mutex);
return ret;
}
#endif /* CONFIG_LIVEPATCH */
#endif /* CONFIG_KALLSYMS */
/* Maximum number of characters written by module_flags() */

View File

@@ -25,7 +25,7 @@ int mod_check_sig(const struct module_signature *ms, size_t file_len,
return -EBADMSG;
if (ms->id_type != PKEY_ID_PKCS7) {
pr_err("%s: Module is not signed with expected PKCS#7 message\n",
pr_err("%s: not signed with expected PKCS#7 message\n",
name);
return -ENOPKG;
}

View File

@@ -30,7 +30,7 @@ int mod_verify_sig(const void *mod, struct load_info *info)
memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms));
ret = mod_check_sig(&ms, modlen, info->name);
ret = mod_check_sig(&ms, modlen, "module");
if (ret)
return ret;

View File

@@ -124,9 +124,9 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
if (!p)
return true;
*p = '\0';
mutex_lock(&module_mutex);
rcu_read_lock_sched();
ret = !!find_module(tk->symbol);
mutex_unlock(&module_mutex);
rcu_read_unlock_sched();
*p = ':';
return ret;