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-rw-r--r--kernel/module.c88
1 files changed, 67 insertions, 21 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 2806c9b6577c..e96209667263 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -430,7 +430,7 @@ static bool each_symbol_in_section(const struct symsearch *arr,
}
/* Returns true as soon as fn returns true, otherwise false. */
-bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
+static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
struct module *owner,
void *data),
void *data)
@@ -491,7 +491,6 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
}
return false;
}
-EXPORT_SYMBOL_GPL(each_symbol_section);
struct find_symbol_arg {
/* Input */
@@ -503,6 +502,7 @@ struct find_symbol_arg {
struct module *owner;
const s32 *crc;
const struct kernel_symbol *sym;
+ enum mod_license license;
};
static bool check_symbol(const struct symsearch *syms,
@@ -512,9 +512,9 @@ static bool check_symbol(const struct symsearch *syms,
struct find_symbol_arg *fsa = data;
if (!fsa->gplok) {
- if (syms->licence == GPL_ONLY)
+ if (syms->license == GPL_ONLY)
return false;
- if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
+ 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);
@@ -536,6 +536,7 @@ static bool check_symbol(const struct symsearch *syms,
fsa->owner = owner;
fsa->crc = symversion(syms->crcs, symnum);
fsa->sym = &syms->start[symnum];
+ fsa->license = syms->license;
return true;
}
@@ -565,9 +566,10 @@ static bool find_symbol_in_section(const struct symsearch *syms,
/* Find a symbol and return it, along with, (optional) crc and
* (optional) module which owns it. Needs preempt disabled or module_mutex. */
-const struct kernel_symbol *find_symbol(const char *name,
+static const struct kernel_symbol *find_symbol(const char *name,
struct module **owner,
const s32 **crc,
+ enum mod_license *license,
bool gplok,
bool warn)
{
@@ -582,13 +584,14 @@ const struct kernel_symbol *find_symbol(const char *name,
*owner = fsa.owner;
if (crc)
*crc = fsa.crc;
+ if (license)
+ *license = fsa.license;
return fsa.sym;
}
pr_debug("Failed to find symbol %s\n", name);
return NULL;
}
-EXPORT_SYMBOL_GPL(find_symbol);
/*
* Search for module by name: must hold module_mutex (or preempt disabled
@@ -850,7 +853,7 @@ static int add_module_usage(struct module *a, struct module *b)
}
/* Module a uses b: caller needs module_mutex() */
-int ref_module(struct module *a, struct module *b)
+static int ref_module(struct module *a, struct module *b)
{
int err;
@@ -869,7 +872,6 @@ int ref_module(struct module *a, struct module *b)
}
return 0;
}
-EXPORT_SYMBOL_GPL(ref_module);
/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
@@ -1058,7 +1060,7 @@ void __symbol_put(const char *symbol)
struct module *owner;
preempt_disable();
- if (!find_symbol(symbol, &owner, NULL, true, false))
+ if (!find_symbol(symbol, &owner, NULL, NULL, true, false))
BUG();
module_put(owner);
preempt_enable();
@@ -1150,11 +1152,10 @@ static inline void module_unload_free(struct module *mod)
{
}
-int ref_module(struct module *a, struct module *b)
+static int ref_module(struct module *a, struct module *b)
{
return strong_try_module_get(b);
}
-EXPORT_SYMBOL_GPL(ref_module);
static inline int module_unload_init(struct module *mod)
{
@@ -1338,7 +1339,7 @@ static inline int check_modstruct_version(const struct load_info *info,
*/
preempt_disable();
if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
- &crc, true, false)) {
+ &crc, NULL, true, false)) {
preempt_enable();
BUG();
}
@@ -1379,6 +1380,25 @@ static inline int same_magic(const char *amagic, const char *bmagic,
}
#endif /* CONFIG_MODVERSIONS */
+static bool inherit_taint(struct module *mod, struct module *owner)
+{
+ if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
+ return true;
+
+ if (mod->using_gplonly_symbols) {
+ pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n",
+ mod->name, owner->name);
+ return false;
+ }
+
+ if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
+ pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n",
+ mod->name, owner->name);
+ set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
+ }
+ return true;
+}
+
/* Resolve a symbol for this module. I.e. if we find one, record usage. */
static const struct kernel_symbol *resolve_symbol(struct module *mod,
const struct load_info *info,
@@ -1388,6 +1408,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
struct module *owner;
const struct kernel_symbol *sym;
const s32 *crc;
+ enum mod_license license;
int err;
/*
@@ -1397,11 +1418,19 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
*/
sched_annotate_sleep();
mutex_lock(&module_mutex);
- sym = find_symbol(name, &owner, &crc,
+ sym = find_symbol(name, &owner, &crc, &license,
!(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
if (!sym)
goto unlock;
+ if (license == GPL_ONLY)
+ mod->using_gplonly_symbols = true;
+
+ if (!inherit_taint(mod, owner)) {
+ sym = NULL;
+ goto getname;
+ }
+
if (!check_version(info, name, mod, crc)) {
sym = ERR_PTR(-EINVAL);
goto getname;
@@ -1789,7 +1818,6 @@ static int mod_sysfs_init(struct module *mod)
if (err)
mod_kobject_put(mod);
- /* delay uevent until full sysfs population */
out:
return err;
}
@@ -1826,7 +1854,6 @@ static int mod_sysfs_setup(struct module *mod,
add_sect_attrs(mod, info);
add_notes_attrs(mod, info);
- kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
return 0;
out_unreg_modinfo_attrs:
@@ -2203,7 +2230,7 @@ void *__symbol_get(const char *symbol)
const struct kernel_symbol *sym;
preempt_disable();
- sym = find_symbol(symbol, &owner, NULL, true, true);
+ sym = find_symbol(symbol, &owner, NULL, NULL, true, true);
if (sym && strong_try_module_get(owner))
sym = NULL;
preempt_enable();
@@ -2238,7 +2265,7 @@ static int verify_export_symbols(struct module *mod)
for (i = 0; i < ARRAY_SIZE(arr); i++) {
for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
- if (find_symbol(s->name, &owner, NULL, true, false)) {
+ if (find_symbol(s->name, &owner, NULL, NULL, true, false)) {
pr_err("%s: exports duplicate symbol %s"
" (owned by %s)\n",
mod->name, s->name, module_name(owner));
@@ -2249,6 +2276,21 @@ static int verify_export_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)
{
@@ -2294,8 +2336,10 @@ 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;
pr_warn("%s: Unknown symbol %s (err %li)\n",
@@ -3481,6 +3525,9 @@ static noinline int do_init_module(struct module *mod)
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_LIVE, mod);
+ /* Delay uevent until module has finished its init routine */
+ kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
+
/*
* We need to finish all async code before the module init sequence
* is done. This has potential to deadlock. For example, a newly
@@ -3801,6 +3848,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
MODULE_STATE_GOING, mod);
klp_module_going(mod);
bug_cleanup:
+ mod->state = MODULE_STATE_GOING;
/* module_bug_cleanup needs module_mutex protection */
mutex_lock(&module_mutex);
module_bug_cleanup(mod);
@@ -4309,7 +4357,6 @@ struct module *__module_address(unsigned long addr)
}
return mod;
}
-EXPORT_SYMBOL_GPL(__module_address);
/*
* is_module_text_address - is this address inside module code?
@@ -4348,7 +4395,6 @@ struct module *__module_text_address(unsigned long addr)
}
return mod;
}
-EXPORT_SYMBOL_GPL(__module_text_address);
/* Don't grab lock, we're oopsing. */
void print_modules(void)
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-04-30 08:32:10 +0000