linux - kernel/module/main.c

3143 lines · 79.9 KiB

1	// SPDX-License-Identifier: GPL-2.0-or-later
2	/*
3	* Copyright (C) 2002 Richard Henderson
4	* Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
5	*/
6
7	#define INCLUDE_VERMAGIC
8
9	#include <linux/export.h>
10	#include <linux/extable.h>
11	#include <linux/moduleloader.h>
12	#include <linux/module_signature.h>
13	#include <linux/trace_events.h>
14	#include <linux/init.h>
15	#include <linux/kallsyms.h>
16	#include <linux/buildid.h>
17	#include <linux/fs.h>
18	#include <linux/kernel.h>
19	#include <linux/kernel_read_file.h>
20	#include <linux/slab.h>
21	#include <linux/vmalloc.h>
22	#include <linux/elf.h>
23	#include <linux/seq_file.h>
24	#include <linux/syscalls.h>
25	#include <linux/fcntl.h>
26	#include <linux/rcupdate.h>
27	#include <linux/capability.h>
28	#include <linux/cpu.h>
29	#include <linux/moduleparam.h>
30	#include <linux/errno.h>
31	#include <linux/err.h>
32	#include <linux/vermagic.h>
33	#include <linux/notifier.h>
34	#include <linux/sched.h>
35	#include <linux/device.h>
36	#include <linux/string.h>
37	#include <linux/mutex.h>
38	#include <linux/rculist.h>
39	#include <linux/uaccess.h>
40	#include <asm/cacheflush.h>
41	#include <linux/set_memory.h>
42	#include <asm/mmu_context.h>
43	#include <linux/license.h>
44	#include <asm/sections.h>
45	#include <linux/tracepoint.h>
46	#include <linux/ftrace.h>
47	#include <linux/livepatch.h>
48	#include <linux/async.h>
49	#include <linux/percpu.h>
50	#include <linux/kmemleak.h>
51	#include <linux/jump_label.h>
52	#include <linux/pfn.h>
53	#include <linux/bsearch.h>
54	#include <linux/dynamic_debug.h>
55	#include <linux/audit.h>
56	#include <linux/cfi.h>
57	#include <uapi/linux/module.h>
58	#include "internal.h"
59
60	#define CREATE_TRACE_POINTS
61	#include <trace/events/module.h>
62
63	/*
64	* Mutex protects:
65	* 1) List of modules (also safely readable with preempt_disable),
66	* 2) module_use links,
67	* 3) mod_tree.addr_min/mod_tree.addr_max.
68	* (delete and add uses RCU list operations).
69	*/
70	DEFINE_MUTEX(module_mutex);
71	LIST_HEAD(modules);
72
73	/* Work queue for freeing init sections in success case */
74	static void do_free_init(struct work_struct *w);
75	static DECLARE_WORK(init_free_wq, do_free_init);
76	static LLIST_HEAD(init_free_list);
77
78	struct mod_tree_root mod_tree __cacheline_aligned = {
79	.addr_min = -1UL,
80	};
81
82	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
83	struct mod_tree_root mod_data_tree __cacheline_aligned = {
84	.addr_min = -1UL,
85	};
86	#endif
87
88	struct symsearch {
89	const struct kernel_symbol start, stop;
90	const s32 *crcs;
91	enum mod_license license;
92	};
93
94	/*
95	* Bounds of module text, for speeding up __module_address.
96	* Protected by module_mutex.
97	*/
98	static void __mod_update_bounds(void base, unsigned int size, struct mod_tree_root tree)
99	{
100	unsigned long min = (unsigned long)base;
101	unsigned long max = min + size;
102
103	if (min < tree->addr_min)
104	tree->addr_min = min;
105	if (max > tree->addr_max)
106	tree->addr_max = max;
107	}
108
109	static void mod_update_bounds(struct module *mod)
110	{
111	__mod_update_bounds(mod->core_layout.base, mod->core_layout.size, &mod_tree);
112	if (mod->init_layout.size)
113	__mod_update_bounds(mod->init_layout.base, mod->init_layout.size, &mod_tree);
114	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
115	__mod_update_bounds(mod->data_layout.base, mod->data_layout.size, &mod_data_tree);
116	#endif
117	}
118
119	/* Block module loading/unloading? */
120	int modules_disabled;
121	core_param(nomodule, modules_disabled, bint, 0);
122
123	/* Waiting for a module to finish initializing? */
124	static DECLARE_WAIT_QUEUE_HEAD(module_wq);
125
126	static BLOCKING_NOTIFIER_HEAD(module_notify_list);
127
128	int register_module_notifier(struct notifier_block *nb)
129	{
130	return blocking_notifier_chain_register(&module_notify_list, nb);
131	}
132	EXPORT_SYMBOL(register_module_notifier);
133
134	int unregister_module_notifier(struct notifier_block *nb)
135	{
136	return blocking_notifier_chain_unregister(&module_notify_list, nb);
137	}
138	EXPORT_SYMBOL(unregister_module_notifier);
139
140	/*
141	* We require a truly strong try_module_get(): 0 means success.
142	* Otherwise an error is returned due to ongoing or failed
143	* initialization etc.
144	*/
145	static inline int strong_try_module_get(struct module *mod)
146	{
147	BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
148	if (mod && mod->state == MODULE_STATE_COMING)
149	return -EBUSY;
150	if (try_module_get(mod))
151	return 0;
152	else
153	return -ENOENT;
154	}
155
156	static inline void add_taint_module(struct module *mod, unsigned flag,
157	enum lockdep_ok lockdep_ok)
158	{
159	add_taint(flag, lockdep_ok);
160	set_bit(flag, &mod->taints);
161	}
162
163	/*
164	* A thread that wants to hold a reference to a module only while it
165	* is running can call this to safely exit.
166	*/
167	void __noreturn __module_put_and_kthread_exit(struct module *mod, long code)
168	{
169	module_put(mod);
170	kthread_exit(code);
171	}
172	EXPORT_SYMBOL(__module_put_and_kthread_exit);
173
174	/* Find a module section: 0 means not found. */
175	static unsigned int find_sec(const struct load_info info, const char name)
176	{
177	unsigned int i;
178
179	for (i = 1; i < info->hdr->e_shnum; i++) {
180	Elf_Shdr *shdr = &info->sechdrs[i];
181	/* Alloc bit cleared means "ignore it." */
182	if ((shdr->sh_flags & SHF_ALLOC)
183	&& strcmp(info->secstrings + shdr->sh_name, name) == 0)
184	return i;
185	}
186	return 0;
187	}
188
189	/* Find a module section, or NULL. */
190	static void section_addr(const struct load_info info, const char *name)
191	{
192	/* Section 0 has sh_addr 0. */
193	return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
194	}
195
196	/* Find a module section, or NULL. Fill in number of "objects" in section. */
197	static void section_objs(const struct load_info info,
198	const char *name,
199	size_t object_size,
200	unsigned int *num)
201	{
202	unsigned int sec = find_sec(info, name);
203
204	/* Section 0 has sh_addr 0 and sh_size 0. */
205	*num = info->sechdrs[sec].sh_size / object_size;
206	return (void *)info->sechdrs[sec].sh_addr;
207	}
208
209	/* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */
210	static unsigned int find_any_sec(const struct load_info info, const char name)
211	{
212	unsigned int i;
213
214	for (i = 1; i < info->hdr->e_shnum; i++) {
215	Elf_Shdr *shdr = &info->sechdrs[i];
216	if (strcmp(info->secstrings + shdr->sh_name, name) == 0)
217	return i;
218	}
219	return 0;
220	}
221
222	/*
223	* Find a module section, or NULL. Fill in number of "objects" in section.
224	* Ignores SHF_ALLOC flag.
225	*/
226	static __maybe_unused void any_section_objs(const struct load_info info,
227	const char *name,
228	size_t object_size,
229	unsigned int *num)
230	{
231	unsigned int sec = find_any_sec(info, name);
232
233	/* Section 0 has sh_addr 0 and sh_size 0. */
234	*num = info->sechdrs[sec].sh_size / object_size;
235	return (void *)info->sechdrs[sec].sh_addr;
236	}
237
238	#ifndef CONFIG_MODVERSIONS
239	#define symversion(base, idx) NULL
240	#else
241	#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
242	#endif
243
244	static const char kernel_symbol_name(const struct kernel_symbol sym)
245	{
246	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
247	return offset_to_ptr(&sym->name_offset);
248	#else
249	return sym->name;
250	#endif
251	}
252
253	static const char kernel_symbol_namespace(const struct kernel_symbol sym)
254	{
255	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
256	if (!sym->namespace_offset)
257	return NULL;
258	return offset_to_ptr(&sym->namespace_offset);
259	#else
260	return sym->namespace;
261	#endif
262	}
263
264	int cmp_name(const void name, const void sym)
265	{
266	return strcmp(name, kernel_symbol_name(sym));
267	}
268
269	static bool find_exported_symbol_in_section(const struct symsearch *syms,
270	struct module *owner,
271	struct find_symbol_arg *fsa)
272	{
273	struct kernel_symbol *sym;
274
275	if (!fsa->gplok && syms->license == GPL_ONLY)
276	return false;
277
278	sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
279	sizeof(struct kernel_symbol), cmp_name);
280	if (!sym)
281	return false;
282
283	fsa->owner = owner;
284	fsa->crc = symversion(syms->crcs, sym - syms->start);
285	fsa->sym = sym;
286	fsa->license = syms->license;
287
288	return true;
289	}
290
291	/*
292	* Find an exported symbol and return it, along with, (optional) crc and
293	* (optional) module which owns it. Needs preempt disabled or module_mutex.
294	*/
295	bool find_symbol(struct find_symbol_arg *fsa)
296	{
297	static const struct symsearch arr[] = {
298	{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
299	NOT_GPL_ONLY },
300	{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
301	__start___kcrctab_gpl,
302	GPL_ONLY },
303	};
304	struct module *mod;
305	unsigned int i;
306
307	module_assert_mutex_or_preempt();
308
309	for (i = 0; i < ARRAY_SIZE(arr); i++)
310	if (find_exported_symbol_in_section(&arr[i], NULL, fsa))
311	return true;
312
313	list_for_each_entry_rcu(mod, &modules, list,
314	lockdep_is_held(&module_mutex)) {
315	struct symsearch arr[] = {
316	{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
317	NOT_GPL_ONLY },
318	{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
319	mod->gpl_crcs,
320	GPL_ONLY },
321	};
322
323	if (mod->state == MODULE_STATE_UNFORMED)
324	continue;
325
326	for (i = 0; i < ARRAY_SIZE(arr); i++)
327	if (find_exported_symbol_in_section(&arr[i], mod, fsa))
328	return true;
329	}
330
331	pr_debug("Failed to find symbol %s\n", fsa->name);
332	return false;
333	}
334
335	/*
336	* Search for module by name: must hold module_mutex (or preempt disabled
337	* for read-only access).
338	*/
339	struct module find_module_all(const char name, size_t len,
340	bool even_unformed)
341	{
342	struct module *mod;
343
344	module_assert_mutex_or_preempt();
345
346	list_for_each_entry_rcu(mod, &modules, list,
347	lockdep_is_held(&module_mutex)) {
348	if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
349	continue;
350	if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
351	return mod;
352	}
353	return NULL;
354	}
355
356	struct module find_module(const char name)
357	{
358	return find_module_all(name, strlen(name), false);
359	}
360
361	#ifdef CONFIG_SMP
362
363	static inline void __percpu mod_percpu(struct module mod)
364	{
365	return mod->percpu;
366	}
367
368	static int percpu_modalloc(struct module mod, struct load_info info)
369	{
370	Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
371	unsigned long align = pcpusec->sh_addralign;
372
373	if (!pcpusec->sh_size)
374	return 0;
375
376	if (align > PAGE_SIZE) {
377	pr_warn("%s: per-cpu alignment %li > %li\n",
378	mod->name, align, PAGE_SIZE);
379	align = PAGE_SIZE;
380	}
381
382	mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
383	if (!mod->percpu) {
384	pr_warn("%s: Could not allocate %lu bytes percpu data\n",
385	mod->name, (unsigned long)pcpusec->sh_size);
386	return -ENOMEM;
387	}
388	mod->percpu_size = pcpusec->sh_size;
389	return 0;
390	}
391
392	static void percpu_modfree(struct module *mod)
393	{
394	free_percpu(mod->percpu);
395	}
396
397	static unsigned int find_pcpusec(struct load_info *info)
398	{
399	return find_sec(info, ".data..percpu");
400	}
401
402	static void percpu_modcopy(struct module *mod,
403	const void *from, unsigned long size)
404	{
405	int cpu;
406
407	for_each_possible_cpu(cpu)
408	memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
409	}
410
411	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
412	{
413	struct module *mod;
414	unsigned int cpu;
415
416	preempt_disable();
417
418	list_for_each_entry_rcu(mod, &modules, list) {
419	if (mod->state == MODULE_STATE_UNFORMED)
420	continue;
421	if (!mod->percpu_size)
422	continue;
423	for_each_possible_cpu(cpu) {
424	void *start = per_cpu_ptr(mod->percpu, cpu);
425	void va = (void )addr;
426
427	if (va >= start && va < start + mod->percpu_size) {
428	if (can_addr) {
429	*can_addr = (unsigned long) (va - start);
430	*can_addr += (unsigned long)
431	per_cpu_ptr(mod->percpu,
432	get_boot_cpu_id());
433	}
434	preempt_enable();
435	return true;
436	}
437	}
438	}
439
440	preempt_enable();
441	return false;
442	}
443
444	/**
445	* is_module_percpu_address() - test whether address is from module static percpu
446	* @addr: address to test
447	*
448	* Test whether @addr belongs to module static percpu area.
449	*
450	* Return: %true if @addr is from module static percpu area
451	*/
452	bool is_module_percpu_address(unsigned long addr)
453	{
454	return __is_module_percpu_address(addr, NULL);
455	}
456
457	#else /* ... !CONFIG_SMP */
458
459	static inline void __percpu mod_percpu(struct module mod)
460	{
461	return NULL;
462	}
463	static int percpu_modalloc(struct module mod, struct load_info info)
464	{
465	/* UP modules shouldn't have this section: ENOMEM isn't quite right */
466	if (info->sechdrs[info->index.pcpu].sh_size != 0)
467	return -ENOMEM;
468	return 0;
469	}
470	static inline void percpu_modfree(struct module *mod)
471	{
472	}
473	static unsigned int find_pcpusec(struct load_info *info)
474	{
475	return 0;
476	}
477	static inline void percpu_modcopy(struct module *mod,
478	const void *from, unsigned long size)
479	{
480	/* pcpusec should be 0, and size of that section should be 0. */
481	BUG_ON(size != 0);
482	}
483	bool is_module_percpu_address(unsigned long addr)
484	{
485	return false;
486	}
487
488	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
489	{
490	return false;
491	}
492
493	#endif /* CONFIG_SMP */
494
495	#define MODINFO_ATTR(field) \
496	static void setup_modinfo_##field(struct module mod, const char s) \
497	{ \
498	mod->field = kstrdup(s, GFP_KERNEL); \
499	} \
500	static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
501	struct module_kobject mk, char buffer) \
502	{ \
503	return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
504	} \
505	static int modinfo_##field##_exists(struct module *mod) \
506	{ \
507	return mod->field != NULL; \
508	} \
509	static void free_modinfo_##field(struct module *mod) \
510	{ \
511	kfree(mod->field); \
512	mod->field = NULL; \
513	} \
514	static struct module_attribute modinfo_##field = { \
515	.attr = { .name = __stringify(field), .mode = 0444 }, \
516	.show = show_modinfo_##field, \
517	.setup = setup_modinfo_##field, \
518	.test = modinfo_##field##_exists, \
519	.free = free_modinfo_##field, \
520	};
521
522	MODINFO_ATTR(version);
523	MODINFO_ATTR(srcversion);
524
525	static struct {
526	char name[MODULE_NAME_LEN + 1];
527	char taints[MODULE_FLAGS_BUF_SIZE];
528	} last_unloaded_module;
529
530	#ifdef CONFIG_MODULE_UNLOAD
531
532	EXPORT_TRACEPOINT_SYMBOL(module_get);
533
534	/* MODULE_REF_BASE is the base reference count by kmodule loader. */
535	#define MODULE_REF_BASE 1
536
537	/* Init the unload section of the module. */
538	static int module_unload_init(struct module *mod)
539	{
540	/*
541	* Initialize reference counter to MODULE_REF_BASE.
542	* refcnt == 0 means module is going.
543	*/
544	atomic_set(&mod->refcnt, MODULE_REF_BASE);
545
546	INIT_LIST_HEAD(&mod->source_list);
547	INIT_LIST_HEAD(&mod->target_list);
548
549	/* Hold reference count during initialization. */
550	atomic_inc(&mod->refcnt);
551
552	return 0;
553	}
554
555	/* Does a already use b? */
556	static int already_uses(struct module a, struct module b)
557	{
558	struct module_use *use;
559
560	list_for_each_entry(use, &b->source_list, source_list) {
561	if (use->source == a) {
562	pr_debug("%s uses %s!\n", a->name, b->name);
563	return 1;
564	}
565	}
566	pr_debug("%s does not use %s!\n", a->name, b->name);
567	return 0;
568	}
569
570	/*
571	* Module a uses b
572	* - we add 'a' as a "source", 'b' as a "target" of module use
573	* - the module_use is added to the list of 'b' sources (so
574	* 'b' can walk the list to see who sourced them), and of 'a'
575	* targets (so 'a' can see what modules it targets).
576	*/
577	static int add_module_usage(struct module a, struct module b)
578	{
579	struct module_use *use;
580
581	pr_debug("Allocating new usage for %s.\n", a->name);
582	use = kmalloc(sizeof(*use), GFP_ATOMIC);
583	if (!use)
584	return -ENOMEM;
585
586	use->source = a;
587	use->target = b;
588	list_add(&use->source_list, &b->source_list);
589	list_add(&use->target_list, &a->target_list);
590	return 0;
591	}
592
593	/* Module a uses b: caller needs module_mutex() */
594	static int ref_module(struct module a, struct module b)
595	{
596	int err;
597
598	if (b == NULL \|\| already_uses(a, b))
599	return 0;
600
601	/* If module isn't available, we fail. */
602	err = strong_try_module_get(b);
603	if (err)
604	return err;
605
606	err = add_module_usage(a, b);
607	if (err) {
608	module_put(b);
609	return err;
610	}
611	return 0;
612	}
613
614	/* Clear the unload stuff of the module. */
615	static void module_unload_free(struct module *mod)
616	{
617	struct module_use use, tmp;
618
619	mutex_lock(&module_mutex);
620	list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
621	struct module *i = use->target;
622	pr_debug("%s unusing %s\n", mod->name, i->name);
623	module_put(i);
624	list_del(&use->source_list);
625	list_del(&use->target_list);
626	kfree(use);
627	}
628	mutex_unlock(&module_mutex);
629	}
630
631	#ifdef CONFIG_MODULE_FORCE_UNLOAD
632	static inline int try_force_unload(unsigned int flags)
633	{
634	int ret = (flags & O_TRUNC);
635	if (ret)
636	add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
637	return ret;
638	}
639	#else
640	static inline int try_force_unload(unsigned int flags)
641	{
642	return 0;
643	}
644	#endif /* CONFIG_MODULE_FORCE_UNLOAD */
645
646	/* Try to release refcount of module, 0 means success. */
647	static int try_release_module_ref(struct module *mod)
648	{
649	int ret;
650
651	/* Try to decrement refcnt which we set at loading */
652	ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
653	BUG_ON(ret < 0);
654	if (ret)
655	/* Someone can put this right now, recover with checking */
656	ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
657
658	return ret;
659	}
660
661	static int try_stop_module(struct module mod, int flags, int forced)
662	{
663	/* If it's not unused, quit unless we're forcing. */
664	if (try_release_module_ref(mod) != 0) {
665	*forced = try_force_unload(flags);
666	if (!(*forced))
667	return -EWOULDBLOCK;
668	}
669
670	/* Mark it as dying. */
671	mod->state = MODULE_STATE_GOING;
672
673	return 0;
674	}
675
676	/**
677	* module_refcount() - return the refcount or -1 if unloading
678	* @mod: the module we're checking
679	*
680	* Return:
681	* -1 if the module is in the process of unloading
682	* otherwise the number of references in the kernel to the module
683	*/
684	int module_refcount(struct module *mod)
685	{
686	return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
687	}
688	EXPORT_SYMBOL(module_refcount);
689
690	/* This exists whether we can unload or not */
691	static void free_module(struct module *mod);
692
693	SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
694	unsigned int, flags)
695	{
696	struct module *mod;
697	char name[MODULE_NAME_LEN];
698	char buf[MODULE_FLAGS_BUF_SIZE];
699	int ret, forced = 0;
700
701	if (!capable(CAP_SYS_MODULE) \|\| modules_disabled)
702	return -EPERM;
703
704	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
705	return -EFAULT;
706	name[MODULE_NAME_LEN-1] = '\0';
707
708	audit_log_kern_module(name);
709
710	if (mutex_lock_interruptible(&module_mutex) != 0)
711	return -EINTR;
712
713	mod = find_module(name);
714	if (!mod) {
715	ret = -ENOENT;
716	goto out;
717	}
718
719	if (!list_empty(&mod->source_list)) {
720	/* Other modules depend on us: get rid of them first. */
721	ret = -EWOULDBLOCK;
722	goto out;
723	}
724
725	/* Doing init or already dying? */
726	if (mod->state != MODULE_STATE_LIVE) {
727	/* FIXME: if (force), slam module count damn the torpedoes */
728	pr_debug("%s already dying\n", mod->name);
729	ret = -EBUSY;
730	goto out;
731	}
732
733	/* If it has an init func, it must have an exit func to unload */
734	if (mod->init && !mod->exit) {
735	forced = try_force_unload(flags);
736	if (!forced) {
737	/* This module can't be removed */
738	ret = -EBUSY;
739	goto out;
740	}
741	}
742
743	ret = try_stop_module(mod, flags, &forced);
744	if (ret != 0)
745	goto out;
746
747	mutex_unlock(&module_mutex);
748	/* Final destruction now no one is using it. */
749	if (mod->exit != NULL)
750	mod->exit();
751	blocking_notifier_call_chain(&module_notify_list,
752	MODULE_STATE_GOING, mod);
753	klp_module_going(mod);
754	ftrace_release_mod(mod);
755
756	async_synchronize_full();
757
758	/* Store the name and taints of the last unloaded module for diagnostic purposes */
759	strscpy(last_unloaded_module.name, mod->name, sizeof(last_unloaded_module.name));
760	strscpy(last_unloaded_module.taints, module_flags(mod, buf, false), sizeof(last_unloaded_module.taints));
761
762	free_module(mod);
763	/* someone could wait for the module in add_unformed_module() */
764	wake_up_all(&module_wq);
765	return 0;
766	out:
767	mutex_unlock(&module_mutex);
768	return ret;
769	}
770
771	void __symbol_put(const char *symbol)
772	{
773	struct find_symbol_arg fsa = {
774	.name = symbol,
775	.gplok = true,
776	};
777
778	preempt_disable();
779	BUG_ON(!find_symbol(&fsa));
780	module_put(fsa.owner);
781	preempt_enable();
782	}
783	EXPORT_SYMBOL(__symbol_put);
784
785	/* Note this assumes addr is a function, which it currently always is. */
786	void symbol_put_addr(void *addr)
787	{
788	struct module *modaddr;
789	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
790
791	if (core_kernel_text(a))
792	return;
793
794	/*
795	* Even though we hold a reference on the module; we still need to
796	* disable preemption in order to safely traverse the data structure.
797	*/
798	preempt_disable();
799	modaddr = __module_text_address(a);
800	BUG_ON(!modaddr);
801	module_put(modaddr);
802	preempt_enable();
803	}
804	EXPORT_SYMBOL_GPL(symbol_put_addr);
805
806	static ssize_t show_refcnt(struct module_attribute *mattr,
807	struct module_kobject mk, char buffer)
808	{
809	return sprintf(buffer, "%i\n", module_refcount(mk->mod));
810	}
811
812	static struct module_attribute modinfo_refcnt =
813	__ATTR(refcnt, 0444, show_refcnt, NULL);
814
815	void __module_get(struct module *module)
816	{
817	if (module) {
818	preempt_disable();
819	atomic_inc(&module->refcnt);
820	trace_module_get(module, _RET_IP_);
821	preempt_enable();
822	}
823	}
824	EXPORT_SYMBOL(__module_get);
825
826	bool try_module_get(struct module *module)
827	{
828	bool ret = true;
829
830	if (module) {
831	preempt_disable();
832	/* Note: here, we can fail to get a reference */
833	if (likely(module_is_live(module) &&
834	atomic_inc_not_zero(&module->refcnt) != 0))
835	trace_module_get(module, _RET_IP_);
836	else
837	ret = false;
838
839	preempt_enable();
840	}
841	return ret;
842	}
843	EXPORT_SYMBOL(try_module_get);
844
845	void module_put(struct module *module)
846	{
847	int ret;
848
849	if (module) {
850	preempt_disable();
851	ret = atomic_dec_if_positive(&module->refcnt);
852	WARN_ON(ret < 0); /* Failed to put refcount */
853	trace_module_put(module, _RET_IP_);
854	preempt_enable();
855	}
856	}
857	EXPORT_SYMBOL(module_put);
858
859	#else /* !CONFIG_MODULE_UNLOAD */
860	static inline void module_unload_free(struct module *mod)
861	{
862	}
863
864	static int ref_module(struct module a, struct module b)
865	{
866	return strong_try_module_get(b);
867	}
868
869	static inline int module_unload_init(struct module *mod)
870	{
871	return 0;
872	}
873	#endif /* CONFIG_MODULE_UNLOAD */
874
875	size_t module_flags_taint(unsigned long taints, char *buf)
876	{
877	size_t l = 0;
878	int i;
879
880	for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
881	if (taint_flags[i].module && test_bit(i, &taints))
882	buf[l++] = taint_flags[i].c_true;
883	}
884
885	return l;
886	}
887
888	static ssize_t show_initstate(struct module_attribute *mattr,
889	struct module_kobject mk, char buffer)
890	{
891	const char *state = "unknown";
892
893	switch (mk->mod->state) {
894	case MODULE_STATE_LIVE:
895	state = "live";
896	break;
897	case MODULE_STATE_COMING:
898	state = "coming";
899	break;
900	case MODULE_STATE_GOING:
901	state = "going";
902	break;
903	default:
904	BUG();
905	}
906	return sprintf(buffer, "%s\n", state);
907	}
908
909	static struct module_attribute modinfo_initstate =
910	__ATTR(initstate, 0444, show_initstate, NULL);
911
912	static ssize_t store_uevent(struct module_attribute *mattr,
913	struct module_kobject *mk,
914	const char *buffer, size_t count)
915	{
916	int rc;
917
918	rc = kobject_synth_uevent(&mk->kobj, buffer, count);
919	return rc ? rc : count;
920	}
921
922	struct module_attribute module_uevent =
923	__ATTR(uevent, 0200, NULL, store_uevent);
924
925	static ssize_t show_coresize(struct module_attribute *mattr,
926	struct module_kobject mk, char buffer)
927	{
928	return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
929	}
930
931	static struct module_attribute modinfo_coresize =
932	__ATTR(coresize, 0444, show_coresize, NULL);
933
934	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
935	static ssize_t show_datasize(struct module_attribute *mattr,
936	struct module_kobject mk, char buffer)
937	{
938	return sprintf(buffer, "%u\n", mk->mod->data_layout.size);
939	}
940
941	static struct module_attribute modinfo_datasize =
942	__ATTR(datasize, 0444, show_datasize, NULL);
943	#endif
944
945	static ssize_t show_initsize(struct module_attribute *mattr,
946	struct module_kobject mk, char buffer)
947	{
948	return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
949	}
950
951	static struct module_attribute modinfo_initsize =
952	__ATTR(initsize, 0444, show_initsize, NULL);
953
954	static ssize_t show_taint(struct module_attribute *mattr,
955	struct module_kobject mk, char buffer)
956	{
957	size_t l;
958
959	l = module_flags_taint(mk->mod->taints, buffer);
960	buffer[l++] = '\n';
961	return l;
962	}
963
964	static struct module_attribute modinfo_taint =
965	__ATTR(taint, 0444, show_taint, NULL);
966
967	struct module_attribute *modinfo_attrs[] = {
968	&module_uevent,
969	&modinfo_version,
970	&modinfo_srcversion,
971	&modinfo_initstate,
972	&modinfo_coresize,
973	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
974	&modinfo_datasize,
975	#endif
976	&modinfo_initsize,
977	&modinfo_taint,
978	#ifdef CONFIG_MODULE_UNLOAD
979	&modinfo_refcnt,
980	#endif
981	NULL,
982	};
983
984	size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);
985
986	static const char vermagic[] = VERMAGIC_STRING;
987
988	int try_to_force_load(struct module mod, const char reason)
989	{
990	#ifdef CONFIG_MODULE_FORCE_LOAD
991	if (!test_taint(TAINT_FORCED_MODULE))
992	pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
993	add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
994	return 0;
995	#else
996	return -ENOEXEC;
997	#endif
998	}
999
1000	static char get_modinfo(const struct load_info info, const char *tag);
1001	static char get_next_modinfo(const struct load_info info, const char *tag,
1002	char *prev);
1003
1004	static int verify_namespace_is_imported(const struct load_info *info,
1005	const struct kernel_symbol *sym,
1006	struct module *mod)
1007	{
1008	const char *namespace;
1009	char *imported_namespace;
1010
1011	namespace = kernel_symbol_namespace(sym);
1012	if (namespace && namespace[0]) {
1013	imported_namespace = get_modinfo(info, "import_ns");
1014	while (imported_namespace) {
1015	if (strcmp(namespace, imported_namespace) == 0)
1016	return 0;
1017	imported_namespace = get_next_modinfo(
1018	info, "import_ns", imported_namespace);
1019	}
1020	#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1021	pr_warn(
1022	#else
1023	pr_err(
1024	#endif
1025	"%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1026	mod->name, kernel_symbol_name(sym), namespace);
1027	#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1028	return -EINVAL;
1029	#endif
1030	}
1031	return 0;
1032	}
1033
1034	static bool inherit_taint(struct module mod, struct module owner, const char *name)
1035	{
1036	if (!owner \|\| !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
1037	return true;
1038
1039	if (mod->using_gplonly_symbols) {
1040	pr_err("%s: module using GPL-only symbols uses symbols %s from proprietary module %s.\n",
1041	mod->name, name, owner->name);
1042	return false;
1043	}
1044
1045	if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
1046	pr_warn("%s: module uses symbols %s from proprietary module %s, inheriting taint.\n",
1047	mod->name, name, owner->name);
1048	set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
1049	}
1050	return true;
1051	}
1052
1053	/* Resolve a symbol for this module. I.e. if we find one, record usage. */
1054	static const struct kernel_symbol resolve_symbol(struct module mod,
1055	const struct load_info *info,
1056	const char *name,
1057	char ownername[])
1058	{
1059	struct find_symbol_arg fsa = {
1060	.name = name,
1061	.gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
1062	.warn = true,
1063	};
1064	int err;
1065
1066	/*
1067	* The module_mutex should not be a heavily contended lock;
1068	* if we get the occasional sleep here, we'll go an extra iteration
1069	* in the wait_event_interruptible(), which is harmless.
1070	*/
1071	sched_annotate_sleep();
1072	mutex_lock(&module_mutex);
1073	if (!find_symbol(&fsa))
1074	goto unlock;
1075
1076	if (fsa.license == GPL_ONLY)
1077	mod->using_gplonly_symbols = true;
1078
1079	if (!inherit_taint(mod, fsa.owner, name)) {
1080	fsa.sym = NULL;
1081	goto getname;
1082	}
1083
1084	if (!check_version(info, name, mod, fsa.crc)) {
1085	fsa.sym = ERR_PTR(-EINVAL);
1086	goto getname;
1087	}
1088
1089	err = verify_namespace_is_imported(info, fsa.sym, mod);
1090	if (err) {
1091	fsa.sym = ERR_PTR(err);
1092	goto getname;
1093	}
1094
1095	err = ref_module(mod, fsa.owner);
1096	if (err) {
1097	fsa.sym = ERR_PTR(err);
1098	goto getname;
1099	}
1100
1101	getname:
1102	/* We must make copy under the lock if we failed to get ref. */
1103	strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
1104	unlock:
1105	mutex_unlock(&module_mutex);
1106	return fsa.sym;
1107	}
1108
1109	static const struct kernel_symbol *
1110	resolve_symbol_wait(struct module *mod,
1111	const struct load_info *info,
1112	const char *name)
1113	{
1114	const struct kernel_symbol *ksym;
1115	char owner[MODULE_NAME_LEN];
1116
1117	if (wait_event_interruptible_timeout(module_wq,
1118	!IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1119	\|\| PTR_ERR(ksym) != -EBUSY,
1120	30 * HZ) <= 0) {
1121	pr_warn("%s: gave up waiting for init of module %s.\n",
1122	mod->name, owner);
1123	}
1124	return ksym;
1125	}
1126
1127	void __weak module_memfree(void *module_region)
1128	{
1129	/*
1130	* This memory may be RO, and freeing RO memory in an interrupt is not
1131	* supported by vmalloc.
1132	*/
1133	WARN_ON(in_interrupt());
1134	vfree(module_region);
1135	}
1136
1137	void __weak module_arch_cleanup(struct module *mod)
1138	{
1139	}
1140
1141	void __weak module_arch_freeing_init(struct module *mod)
1142	{
1143	}
1144
1145	/* Free a module, remove from lists, etc. */
1146	static void free_module(struct module *mod)
1147	{
1148	trace_module_free(mod);
1149
1150	mod_sysfs_teardown(mod);
1151
1152	/*
1153	* We leave it in list to prevent duplicate loads, but make sure
1154	* that noone uses it while it's being deconstructed.
1155	*/
1156	mutex_lock(&module_mutex);
1157	mod->state = MODULE_STATE_UNFORMED;
1158	mutex_unlock(&module_mutex);
1159
1160	/* Remove dynamic debug info */
1161	ddebug_remove_module(mod->name);
1162
1163	/* Arch-specific cleanup. */
1164	module_arch_cleanup(mod);
1165
1166	/* Module unload stuff */
1167	module_unload_free(mod);
1168
1169	/* Free any allocated parameters. */
1170	destroy_params(mod->kp, mod->num_kp);
1171
1172	if (is_livepatch_module(mod))
1173	free_module_elf(mod);
1174
1175	/* Now we can delete it from the lists */
1176	mutex_lock(&module_mutex);
1177	/* Unlink carefully: kallsyms could be walking list. */
1178	list_del_rcu(&mod->list);
1179	mod_tree_remove(mod);
1180	/* Remove this module from bug list, this uses list_del_rcu */
1181	module_bug_cleanup(mod);
1182	/* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
1183	synchronize_rcu();
1184	if (try_add_tainted_module(mod))
1185	pr_err("%s: adding tainted module to the unloaded tainted modules list failed.\n",
1186	mod->name);
1187	mutex_unlock(&module_mutex);
1188
1189	/* This may be empty, but that's OK */
1190	module_arch_freeing_init(mod);
1191	module_memfree(mod->init_layout.base);
1192	kfree(mod->args);
1193	percpu_modfree(mod);
1194
1195	/* Free lock-classes; relies on the preceding sync_rcu(). */
1196	lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size);
1197
1198	/* Finally, free the core (containing the module structure) */
1199	module_memfree(mod->core_layout.base);
1200	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
1201	vfree(mod->data_layout.base);
1202	#endif
1203	}
1204
1205	void __symbol_get(const char symbol)
1206	{
1207	struct find_symbol_arg fsa = {
1208	.name = symbol,
1209	.gplok = true,
1210	.warn = true,
1211	};
1212
1213	preempt_disable();
1214	if (!find_symbol(&fsa) \|\| strong_try_module_get(fsa.owner)) {
1215	preempt_enable();
1216	return NULL;
1217	}
1218	preempt_enable();
1219	return (void *)kernel_symbol_value(fsa.sym);
1220	}
1221	EXPORT_SYMBOL_GPL(__symbol_get);
1222
1223	/*
1224	* Ensure that an exported symbol [global namespace] does not already exist
1225	* in the kernel or in some other module's exported symbol table.
1226	*
1227	* You must hold the module_mutex.
1228	*/
1229	static int verify_exported_symbols(struct module *mod)
1230	{
1231	unsigned int i;
1232	const struct kernel_symbol *s;
1233	struct {
1234	const struct kernel_symbol *sym;
1235	unsigned int num;
1236	} arr[] = {
1237	{ mod->syms, mod->num_syms },
1238	{ mod->gpl_syms, mod->num_gpl_syms },
1239	};
1240
1241	for (i = 0; i < ARRAY_SIZE(arr); i++) {
1242	for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1243	struct find_symbol_arg fsa = {
1244	.name = kernel_symbol_name(s),
1245	.gplok = true,
1246	};
1247	if (find_symbol(&fsa)) {
1248	pr_err("%s: exports duplicate symbol %s"
1249	" (owned by %s)\n",
1250	mod->name, kernel_symbol_name(s),
1251	module_name(fsa.owner));
1252	return -ENOEXEC;
1253	}
1254	}
1255	}
1256	return 0;
1257	}
1258
1259	static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
1260	{
1261	/*
1262	* On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
1263	* before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
1264	* i386 has a similar problem but may not deserve a fix.
1265	*
1266	* If we ever have to ignore many symbols, consider refactoring the code to
1267	* only warn if referenced by a relocation.
1268	*/
1269	if (emachine == EM_386 \|\| emachine == EM_X86_64)
1270	return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
1271	return false;
1272	}
1273
1274	/* Change all symbols so that st_value encodes the pointer directly. */
1275	static int simplify_symbols(struct module mod, const struct load_info info)
1276	{
1277	Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1278	Elf_Sym sym = (void )symsec->sh_addr;
1279	unsigned long secbase;
1280	unsigned int i;
1281	int ret = 0;
1282	const struct kernel_symbol *ksym;
1283
1284	for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1285	const char *name = info->strtab + sym[i].st_name;
1286
1287	switch (sym[i].st_shndx) {
1288	case SHN_COMMON:
1289	/* Ignore common symbols */
1290	if (!strncmp(name, "__gnu_lto", 9))
1291	break;
1292
1293	/*
1294	* We compiled with -fno-common. These are not
1295	* supposed to happen.
1296	*/
1297	pr_debug("Common symbol: %s\n", name);
1298	pr_warn("%s: please compile with -fno-common\n",
1299	mod->name);
1300	ret = -ENOEXEC;
1301	break;
1302
1303	case SHN_ABS:
1304	/* Don't need to do anything */
1305	pr_debug("Absolute symbol: 0x%08lx\n",
1306	(long)sym[i].st_value);
1307	break;
1308
1309	case SHN_LIVEPATCH:
1310	/* Livepatch symbols are resolved by livepatch */
1311	break;
1312
1313	case SHN_UNDEF:
1314	ksym = resolve_symbol_wait(mod, info, name);
1315	/* Ok if resolved. */
1316	if (ksym && !IS_ERR(ksym)) {
1317	sym[i].st_value = kernel_symbol_value(ksym);
1318	break;
1319	}
1320
1321	/* Ok if weak or ignored. */
1322	if (!ksym &&
1323	(ELF_ST_BIND(sym[i].st_info) == STB_WEAK \|\|
1324	ignore_undef_symbol(info->hdr->e_machine, name)))
1325	break;
1326
1327	ret = PTR_ERR(ksym) ?: -ENOENT;
1328	pr_warn("%s: Unknown symbol %s (err %d)\n",
1329	mod->name, name, ret);
1330	break;
1331
1332	default:
1333	/* Divert to percpu allocation if a percpu var. */
1334	if (sym[i].st_shndx == info->index.pcpu)
1335	secbase = (unsigned long)mod_percpu(mod);
1336	else
1337	secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1338	sym[i].st_value += secbase;
1339	break;
1340	}
1341	}
1342
1343	return ret;
1344	}
1345
1346	static int apply_relocations(struct module mod, const struct load_info info)
1347	{
1348	unsigned int i;
1349	int err = 0;
1350
1351	/* Now do relocations. */
1352	for (i = 1; i < info->hdr->e_shnum; i++) {
1353	unsigned int infosec = info->sechdrs[i].sh_info;
1354
1355	/* Not a valid relocation section? */
1356	if (infosec >= info->hdr->e_shnum)
1357	continue;
1358
1359	/* Don't bother with non-allocated sections */
1360	if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
1361	continue;
1362
1363	if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
1364	err = klp_apply_section_relocs(mod, info->sechdrs,
1365	info->secstrings,
1366	info->strtab,
1367	info->index.sym, i,
1368	NULL);
1369	else if (info->sechdrs[i].sh_type == SHT_REL)
1370	err = apply_relocate(info->sechdrs, info->strtab,
1371	info->index.sym, i, mod);
1372	else if (info->sechdrs[i].sh_type == SHT_RELA)
1373	err = apply_relocate_add(info->sechdrs, info->strtab,
1374	info->index.sym, i, mod);
1375	if (err < 0)
1376	break;
1377	}
1378	return err;
1379	}
1380
1381	/* Additional bytes needed by arch in front of individual sections */
1382	unsigned int __weak arch_mod_section_prepend(struct module *mod,
1383	unsigned int section)
1384	{
1385	/* default implementation just returns zero */
1386	return 0;
1387	}
1388
1389	/* Update size with this section: return offset. */
1390	long module_get_offset(struct module mod, unsigned int size,
1391	Elf_Shdr *sechdr, unsigned int section)
1392	{
1393	long ret;
1394
1395	*size += arch_mod_section_prepend(mod, section);
1396	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
1397	*size = ret + sechdr->sh_size;
1398	return ret;
1399	}
1400
1401	static bool module_init_layout_section(const char *sname)
1402	{
1403	#ifndef CONFIG_MODULE_UNLOAD
1404	if (module_exit_section(sname))
1405	return true;
1406	#endif
1407	return module_init_section(sname);
1408	}
1409
1410	/*
1411	* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1412	* might -- code, read-only data, read-write data, small data. Tally
1413	* sizes, and place the offsets into sh_entsize fields: high bit means it
1414	* belongs in init.
1415	*/
1416	static void layout_sections(struct module mod, struct load_info info)
1417	{
1418	static unsigned long const masks[][2] = {
1419	/*
1420	* NOTE: all executable code must be the first section
1421	* in this array; otherwise modify the text_size
1422	* finder in the two loops below
1423	*/
1424	{ SHF_EXECINSTR \| SHF_ALLOC, ARCH_SHF_SMALL },
1425	{ SHF_ALLOC, SHF_WRITE \| ARCH_SHF_SMALL },
1426	{ SHF_RO_AFTER_INIT \| SHF_ALLOC, ARCH_SHF_SMALL },
1427	{ SHF_WRITE \| SHF_ALLOC, ARCH_SHF_SMALL },
1428	{ ARCH_SHF_SMALL \| SHF_ALLOC, 0 }
1429	};
1430	unsigned int m, i;
1431
1432	for (i = 0; i < info->hdr->e_shnum; i++)
1433	info->sechdrs[i].sh_entsize = ~0UL;
1434
1435	pr_debug("Core section allocation order:\n");
1436	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1437	for (i = 0; i < info->hdr->e_shnum; ++i) {
1438	Elf_Shdr *s = &info->sechdrs[i];
1439	const char *sname = info->secstrings + s->sh_name;
1440	unsigned int *sizep;
1441
1442	if ((s->sh_flags & masks[m][0]) != masks[m][0]
1443	\|\| (s->sh_flags & masks[m][1])
1444	\|\| s->sh_entsize != ~0UL
1445	\|\| module_init_layout_section(sname))
1446	continue;
1447	sizep = m ? &mod->data_layout.size : &mod->core_layout.size;
1448	s->sh_entsize = module_get_offset(mod, sizep, s, i);
1449	pr_debug("\t%s\n", sname);
1450	}
1451	switch (m) {
1452	case 0: /* executable */
1453	mod->core_layout.size = strict_align(mod->core_layout.size);
1454	mod->core_layout.text_size = mod->core_layout.size;
1455	break;
1456	case 1: /* RO: text and ro-data */
1457	mod->data_layout.size = strict_align(mod->data_layout.size);
1458	mod->data_layout.ro_size = mod->data_layout.size;
1459	break;
1460	case 2: /* RO after init */
1461	mod->data_layout.size = strict_align(mod->data_layout.size);
1462	mod->data_layout.ro_after_init_size = mod->data_layout.size;
1463	break;
1464	case 4: /* whole core */
1465	mod->data_layout.size = strict_align(mod->data_layout.size);
1466	break;
1467	}
1468	}
1469
1470	pr_debug("Init section allocation order:\n");
1471	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1472	for (i = 0; i < info->hdr->e_shnum; ++i) {
1473	Elf_Shdr *s = &info->sechdrs[i];
1474	const char *sname = info->secstrings + s->sh_name;
1475
1476	if ((s->sh_flags & masks[m][0]) != masks[m][0]
1477	\|\| (s->sh_flags & masks[m][1])
1478	\|\| s->sh_entsize != ~0UL
1479	\|\| !module_init_layout_section(sname))
1480	continue;
1481	s->sh_entsize = (module_get_offset(mod, &mod->init_layout.size, s, i)
1482	\| INIT_OFFSET_MASK);
1483	pr_debug("\t%s\n", sname);
1484	}
1485	switch (m) {
1486	case 0: /* executable */
1487	mod->init_layout.size = strict_align(mod->init_layout.size);
1488	mod->init_layout.text_size = mod->init_layout.size;
1489	break;
1490	case 1: /* RO: text and ro-data */
1491	mod->init_layout.size = strict_align(mod->init_layout.size);
1492	mod->init_layout.ro_size = mod->init_layout.size;
1493	break;
1494	case 2:
1495	/*
1496	* RO after init doesn't apply to init_layout (only
1497	* core_layout), so it just takes the value of ro_size.
1498	*/
1499	mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
1500	break;
1501	case 4: /* whole init */
1502	mod->init_layout.size = strict_align(mod->init_layout.size);
1503	break;
1504	}
1505	}
1506	}
1507
1508	static void set_license(struct module mod, const char license)
1509	{
1510	if (!license)
1511	license = "unspecified";
1512
1513	if (!license_is_gpl_compatible(license)) {
1514	if (!test_taint(TAINT_PROPRIETARY_MODULE))
1515	pr_warn("%s: module license '%s' taints kernel.\n",
1516	mod->name, license);
1517	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
1518	LOCKDEP_NOW_UNRELIABLE);
1519	}
1520	}
1521
1522	/* Parse tag=value strings from .modinfo section */
1523	static char next_string(char string, unsigned long *secsize)
1524	{
1525	/* Skip non-zero chars */
1526	while (string[0]) {
1527	string++;
1528	if ((*secsize)-- <= 1)
1529	return NULL;
1530	}
1531
1532	/* Skip any zero padding. */
1533	while (!string[0]) {
1534	string++;
1535	if ((*secsize)-- <= 1)
1536	return NULL;
1537	}
1538	return string;
1539	}
1540
1541	static char get_next_modinfo(const struct load_info info, const char *tag,
1542	char *prev)
1543	{
1544	char *p;
1545	unsigned int taglen = strlen(tag);
1546	Elf_Shdr *infosec = &info->sechdrs[info->index.info];
1547	unsigned long size = infosec->sh_size;
1548
1549	/*
1550	* get_modinfo() calls made before rewrite_section_headers()
1551	* must use sh_offset, as sh_addr isn't set!
1552	*/
1553	char modinfo = (char )info->hdr + infosec->sh_offset;
1554
1555	if (prev) {
1556	size -= prev - modinfo;
1557	modinfo = next_string(prev, &size);
1558	}
1559
1560	for (p = modinfo; p; p = next_string(p, &size)) {
1561	if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1562	return p + taglen + 1;
1563	}
1564	return NULL;
1565	}
1566
1567	static char get_modinfo(const struct load_info info, const char *tag)
1568	{
1569	return get_next_modinfo(info, tag, NULL);
1570	}
1571
1572	static void setup_modinfo(struct module mod, struct load_info info)
1573	{
1574	struct module_attribute *attr;
1575	int i;
1576
1577	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1578	if (attr->setup)
1579	attr->setup(mod, get_modinfo(info, attr->attr.name));
1580	}
1581	}
1582
1583	static void free_modinfo(struct module *mod)
1584	{
1585	struct module_attribute *attr;
1586	int i;
1587
1588	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1589	if (attr->free)
1590	attr->free(mod);
1591	}
1592	}
1593
1594	static void dynamic_debug_setup(struct module mod, struct _ddebug_info dyndbg)
1595	{
1596	if (!dyndbg->num_descs)
1597	return;
1598	ddebug_add_module(dyndbg, mod->name);
1599	}
1600
1601	static void dynamic_debug_remove(struct module mod, struct _ddebug_info dyndbg)
1602	{
1603	if (dyndbg->num_descs)
1604	ddebug_remove_module(mod->name);
1605	}
1606
1607	void * __weak module_alloc(unsigned long size)
1608	{
1609	return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
1610	GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS,
1611	NUMA_NO_NODE, __builtin_return_address(0));
1612	}
1613
1614	bool __weak module_init_section(const char *name)
1615	{
1616	return strstarts(name, ".init");
1617	}
1618
1619	bool __weak module_exit_section(const char *name)
1620	{
1621	return strstarts(name, ".exit");
1622	}
1623
1624	static int validate_section_offset(struct load_info info, Elf_Shdr shdr)
1625	{
1626	#if defined(CONFIG_64BIT)
1627	unsigned long long secend;
1628	#else
1629	unsigned long secend;
1630	#endif
1631
1632	/*
1633	* Check for both overflow and offset/size being
1634	* too large.
1635	*/
1636	secend = shdr->sh_offset + shdr->sh_size;
1637	if (secend < shdr->sh_offset \|\| secend > info->len)
1638	return -ENOEXEC;
1639
1640	return 0;
1641	}
1642
1643	/*
1644	* Sanity checks against invalid binaries, wrong arch, weird elf version.
1645	*
1646	* Also do basic validity checks against section offsets and sizes, the
1647	* section name string table, and the indices used for it (sh_name).
1648	*/
1649	static int elf_validity_check(struct load_info *info)
1650	{
1651	unsigned int i;
1652	Elf_Shdr shdr, strhdr;
1653	int err;
1654
1655	if (info->len < sizeof(*(info->hdr))) {
1656	pr_err("Invalid ELF header len %lu\n", info->len);
1657	goto no_exec;
1658	}
1659
1660	if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0) {
1661	pr_err("Invalid ELF header magic: != %s\n", ELFMAG);
1662	goto no_exec;
1663	}
1664	if (info->hdr->e_type != ET_REL) {
1665	pr_err("Invalid ELF header type: %u != %u\n",
1666	info->hdr->e_type, ET_REL);
1667	goto no_exec;
1668	}
1669	if (!elf_check_arch(info->hdr)) {
1670	pr_err("Invalid architecture in ELF header: %u\n",
1671	info->hdr->e_machine);
1672	goto no_exec;
1673	}
1674	if (!module_elf_check_arch(info->hdr)) {
1675	pr_err("Invalid module architecture in ELF header: %u\n",
1676	info->hdr->e_machine);
1677	goto no_exec;
1678	}
1679	if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) {
1680	pr_err("Invalid ELF section header size\n");
1681	goto no_exec;
1682	}
1683
1684	/*
1685	* e_shnum is 16 bits, and sizeof(Elf_Shdr) is
1686	* known and small. So e_shnum * sizeof(Elf_Shdr)
1687	* will not overflow unsigned long on any platform.
1688	*/
1689	if (info->hdr->e_shoff >= info->len
1690	\|\| (info->hdr->e_shnum * sizeof(Elf_Shdr) >
1691	info->len - info->hdr->e_shoff)) {
1692	pr_err("Invalid ELF section header overflow\n");
1693	goto no_exec;
1694	}
1695
1696	info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
1697
1698	/*
1699	* Verify if the section name table index is valid.
1700	*/
1701	if (info->hdr->e_shstrndx == SHN_UNDEF
1702	\|\| info->hdr->e_shstrndx >= info->hdr->e_shnum) {
1703	pr_err("Invalid ELF section name index: %d \|\| e_shstrndx (%d) >= e_shnum (%d)\n",
1704	info->hdr->e_shstrndx, info->hdr->e_shstrndx,
1705	info->hdr->e_shnum);
1706	goto no_exec;
1707	}
1708
1709	strhdr = &info->sechdrs[info->hdr->e_shstrndx];
1710	err = validate_section_offset(info, strhdr);
1711	if (err < 0) {
1712	pr_err("Invalid ELF section hdr(type %u)\n", strhdr->sh_type);
1713	return err;
1714	}
1715
1716	/*
1717	* The section name table must be NUL-terminated, as required
1718	* by the spec. This makes strcmp and pr_* calls that access
1719	* strings in the section safe.
1720	*/
1721	info->secstrings = (void *)info->hdr + strhdr->sh_offset;
1722	if (strhdr->sh_size == 0) {
1723	pr_err("empty section name table\n");
1724	goto no_exec;
1725	}
1726	if (info->secstrings[strhdr->sh_size - 1] != '\0') {
1727	pr_err("ELF Spec violation: section name table isn't null terminated\n");
1728	goto no_exec;
1729	}
1730
1731	/*
1732	* The code assumes that section 0 has a length of zero and
1733	* an addr of zero, so check for it.
1734	*/
1735	if (info->sechdrs[0].sh_type != SHT_NULL
1736	\|\| info->sechdrs[0].sh_size != 0
1737	\|\| info->sechdrs[0].sh_addr != 0) {
1738	pr_err("ELF Spec violation: section 0 type(%d)!=SH_NULL or non-zero len or addr\n",
1739	info->sechdrs[0].sh_type);
1740	goto no_exec;
1741	}
1742
1743	for (i = 1; i < info->hdr->e_shnum; i++) {
1744	shdr = &info->sechdrs[i];
1745	switch (shdr->sh_type) {
1746	case SHT_NULL:
1747	case SHT_NOBITS:
1748	continue;
1749	case SHT_SYMTAB:
1750	if (shdr->sh_link == SHN_UNDEF
1751	\|\| shdr->sh_link >= info->hdr->e_shnum) {
1752	pr_err("Invalid ELF sh_link!=SHN_UNDEF(%d) or (sh_link(%d) >= hdr->e_shnum(%d)\n",
1753	shdr->sh_link, shdr->sh_link,
1754	info->hdr->e_shnum);
1755	goto no_exec;
1756	}
1757	fallthrough;
1758	default:
1759	err = validate_section_offset(info, shdr);
1760	if (err < 0) {
1761	pr_err("Invalid ELF section in module (section %u type %u)\n",
1762	i, shdr->sh_type);
1763	return err;
1764	}
1765
1766	if (shdr->sh_flags & SHF_ALLOC) {
1767	if (shdr->sh_name >= strhdr->sh_size) {
1768	pr_err("Invalid ELF section name in module (section %u type %u)\n",
1769	i, shdr->sh_type);
1770	return -ENOEXEC;
1771	}
1772	}
1773	break;
1774	}
1775	}
1776
1777	return 0;
1778
1779	no_exec:
1780	return -ENOEXEC;
1781	}
1782
1783	#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
1784
1785	static int copy_chunked_from_user(void dst, const void __user usrc, unsigned long len)
1786	{
1787	do {
1788	unsigned long n = min(len, COPY_CHUNK_SIZE);
1789
1790	if (copy_from_user(dst, usrc, n) != 0)
1791	return -EFAULT;
1792	cond_resched();
1793	dst += n;
1794	usrc += n;
1795	len -= n;
1796	} while (len);
1797	return 0;
1798	}
1799
1800	static int check_modinfo_livepatch(struct module mod, struct load_info info)
1801	{
1802	if (!get_modinfo(info, "livepatch"))
1803	/* Nothing more to do */
1804	return 0;
1805
1806	if (set_livepatch_module(mod)) {
1807	add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK);
1808	pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
1809	mod->name);
1810	return 0;
1811	}
1812
1813	pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
1814	mod->name);
1815	return -ENOEXEC;
1816	}
1817
1818	static void check_modinfo_retpoline(struct module mod, struct load_info info)
1819	{
1820	if (retpoline_module_ok(get_modinfo(info, "retpoline")))
1821	return;
1822
1823	pr_warn("%s: loading module not compiled with retpoline compiler.\n",
1824	mod->name);
1825	}
1826
1827	/* Sets info->hdr and info->len. */
1828	static int copy_module_from_user(const void __user *umod, unsigned long len,
1829	struct load_info *info)
1830	{
1831	int err;
1832
1833	info->len = len;
1834	if (info->len < sizeof(*(info->hdr)))
1835	return -ENOEXEC;
1836
1837	err = security_kernel_load_data(LOADING_MODULE, true);
1838	if (err)
1839	return err;
1840
1841	/* Suck in entire file: we'll want most of it. */
1842	info->hdr = __vmalloc(info->len, GFP_KERNEL \| __GFP_NOWARN);
1843	if (!info->hdr)
1844	return -ENOMEM;
1845
1846	if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
1847	err = -EFAULT;
1848	goto out;
1849	}
1850
1851	err = security_kernel_post_load_data((char *)info->hdr, info->len,
1852	LOADING_MODULE, "init_module");
1853	out:
1854	if (err)
1855	vfree(info->hdr);
1856
1857	return err;
1858	}
1859
1860	static void free_copy(struct load_info *info, int flags)
1861	{
1862	if (flags & MODULE_INIT_COMPRESSED_FILE)
1863	module_decompress_cleanup(info);
1864	else
1865	vfree(info->hdr);
1866	}
1867
1868	static int rewrite_section_headers(struct load_info *info, int flags)
1869	{
1870	unsigned int i;
1871
1872	/* This should always be true, but let's be sure. */
1873	info->sechdrs[0].sh_addr = 0;
1874
1875	for (i = 1; i < info->hdr->e_shnum; i++) {
1876	Elf_Shdr *shdr = &info->sechdrs[i];
1877
1878	/*
1879	* Mark all sections sh_addr with their address in the
1880	* temporary image.
1881	*/
1882	shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
1883
1884	}
1885
1886	/* Track but don't keep modinfo and version sections. */
1887	info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
1888	info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
1889
1890	return 0;
1891	}
1892
1893	/*
1894	* Set up our basic convenience variables (pointers to section headers,
1895	* search for module section index etc), and do some basic section
1896	* verification.
1897	*
1898	* Set info->mod to the temporary copy of the module in info->hdr. The final one
1899	* will be allocated in move_module().
1900	*/
1901	static int setup_load_info(struct load_info *info, int flags)
1902	{
1903	unsigned int i;
1904
1905	/* Try to find a name early so we can log errors with a module name */
1906	info->index.info = find_sec(info, ".modinfo");
1907	if (info->index.info)
1908	info->name = get_modinfo(info, "name");
1909
1910	/* Find internal symbols and strings. */
1911	for (i = 1; i < info->hdr->e_shnum; i++) {
1912	if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
1913	info->index.sym = i;
1914	info->index.str = info->sechdrs[i].sh_link;
1915	info->strtab = (char *)info->hdr
1916	+ info->sechdrs[info->index.str].sh_offset;
1917	break;
1918	}
1919	}
1920
1921	if (info->index.sym == 0) {
1922	pr_warn("%s: module has no symbols (stripped?)\n",
1923	info->name ?: "(missing .modinfo section or name field)");
1924	return -ENOEXEC;
1925	}
1926
1927	info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
1928	if (!info->index.mod) {
1929	pr_warn("%s: No module found in object\n",
1930	info->name ?: "(missing .modinfo section or name field)");
1931	return -ENOEXEC;
1932	}
1933	/* This is temporary: point mod into copy of data. */
1934	info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;
1935
1936	/*
1937	* If we didn't load the .modinfo 'name' field earlier, fall back to
1938	* on-disk struct mod 'name' field.
1939	*/
1940	if (!info->name)
1941	info->name = info->mod->name;
1942
1943	if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
1944	info->index.vers = 0; /* Pretend no __versions section! */
1945	else
1946	info->index.vers = find_sec(info, "__versions");
1947
1948	info->index.pcpu = find_pcpusec(info);
1949
1950	return 0;
1951	}
1952
1953	static int check_modinfo(struct module mod, struct load_info info, int flags)
1954	{
1955	const char *modmagic = get_modinfo(info, "vermagic");
1956	int err;
1957
1958	if (flags & MODULE_INIT_IGNORE_VERMAGIC)
1959	modmagic = NULL;
1960
1961	/* This is allowed: modprobe --force will invalidate it. */
1962	if (!modmagic) {
1963	err = try_to_force_load(mod, "bad vermagic");
1964	if (err)
1965	return err;
1966	} else if (!same_magic(modmagic, vermagic, info->index.vers)) {
1967	pr_err("%s: version magic '%s' should be '%s'\n",
1968	info->name, modmagic, vermagic);
1969	return -ENOEXEC;
1970	}
1971
1972	if (!get_modinfo(info, "intree")) {
1973	if (!test_taint(TAINT_OOT_MODULE))
1974	pr_warn("%s: loading out-of-tree module taints kernel.\n",
1975	mod->name);
1976	add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
1977	}
1978
1979	check_modinfo_retpoline(mod, info);
1980
1981	if (get_modinfo(info, "staging")) {
1982	add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
1983	pr_warn("%s: module is from the staging directory, the quality "
1984	"is unknown, you have been warned.\n", mod->name);
1985	}
1986
1987	err = check_modinfo_livepatch(mod, info);
1988	if (err)
1989	return err;
1990
1991	/* Set up license info based on the info section */
1992	set_license(mod, get_modinfo(info, "license"));
1993
1994	if (get_modinfo(info, "test")) {
1995	if (!test_taint(TAINT_TEST))
1996	pr_warn("%s: loading test module taints kernel.\n",
1997	mod->name);
1998	add_taint_module(mod, TAINT_TEST, LOCKDEP_STILL_OK);
1999	}
2000
2001	return 0;
2002	}
2003
2004	static int find_module_sections(struct module mod, struct load_info info)
2005	{
2006	mod->kp = section_objs(info, "__param",
2007	sizeof(*mod->kp), &mod->num_kp);
2008	mod->syms = section_objs(info, "__ksymtab",
2009	sizeof(*mod->syms), &mod->num_syms);
2010	mod->crcs = section_addr(info, "__kcrctab");
2011	mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2012	sizeof(*mod->gpl_syms),
2013	&mod->num_gpl_syms);
2014	mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2015
2016	#ifdef CONFIG_CONSTRUCTORS
2017	mod->ctors = section_objs(info, ".ctors",
2018	sizeof(*mod->ctors), &mod->num_ctors);
2019	if (!mod->ctors)
2020	mod->ctors = section_objs(info, ".init_array",
2021	sizeof(*mod->ctors), &mod->num_ctors);
2022	else if (find_sec(info, ".init_array")) {
2023	/*
2024	* This shouldn't happen with same compiler and binutils
2025	* building all parts of the module.
2026	*/
2027	pr_warn("%s: has both .ctors and .init_array.\n",
2028	mod->name);
2029	return -EINVAL;
2030	}
2031	#endif
2032
2033	mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1,
2034	&mod->noinstr_text_size);
2035
2036	#ifdef CONFIG_TRACEPOINTS
2037	mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2038	sizeof(*mod->tracepoints_ptrs),
2039	&mod->num_tracepoints);
2040	#endif
2041	#ifdef CONFIG_TREE_SRCU
2042	mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs",
2043	sizeof(*mod->srcu_struct_ptrs),
2044	&mod->num_srcu_structs);
2045	#endif
2046	#ifdef CONFIG_BPF_EVENTS
2047	mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map",
2048	sizeof(*mod->bpf_raw_events),
2049	&mod->num_bpf_raw_events);
2050	#endif
2051	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
2052	mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size);
2053	#endif
2054	#ifdef CONFIG_JUMP_LABEL
2055	mod->jump_entries = section_objs(info, "__jump_table",
2056	sizeof(*mod->jump_entries),
2057	&mod->num_jump_entries);
2058	#endif
2059	#ifdef CONFIG_EVENT_TRACING
2060	mod->trace_events = section_objs(info, "_ftrace_events",
2061	sizeof(*mod->trace_events),
2062	&mod->num_trace_events);
2063	mod->trace_evals = section_objs(info, "_ftrace_eval_map",
2064	sizeof(*mod->trace_evals),
2065	&mod->num_trace_evals);
2066	#endif
2067	#ifdef CONFIG_TRACING
2068	mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2069	sizeof(*mod->trace_bprintk_fmt_start),
2070	&mod->num_trace_bprintk_fmt);
2071	#endif
2072	#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2073	/* sechdrs[0].sh_size is always zero */
2074	mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION,
2075	sizeof(*mod->ftrace_callsites),
2076	&mod->num_ftrace_callsites);
2077	#endif
2078	#ifdef CONFIG_FUNCTION_ERROR_INJECTION
2079	mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
2080	sizeof(*mod->ei_funcs),
2081	&mod->num_ei_funcs);
2082	#endif
2083	#ifdef CONFIG_KPROBES
2084	mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1,
2085	&mod->kprobes_text_size);
2086	mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist",
2087	sizeof(unsigned long),
2088	&mod->num_kprobe_blacklist);
2089	#endif
2090	#ifdef CONFIG_PRINTK_INDEX
2091	mod->printk_index_start = section_objs(info, ".printk_index",
2092	sizeof(*mod->printk_index_start),
2093	&mod->printk_index_size);
2094	#endif
2095	#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
2096	mod->static_call_sites = section_objs(info, ".static_call_sites",
2097	sizeof(*mod->static_call_sites),
2098	&mod->num_static_call_sites);
2099	#endif
2100	#if IS_ENABLED(CONFIG_KUNIT)
2101	mod->kunit_suites = section_objs(info, ".kunit_test_suites",
2102	sizeof(*mod->kunit_suites),
2103	&mod->num_kunit_suites);
2104	#endif
2105
2106	mod->extable = section_objs(info, "__ex_table",
2107	sizeof(*mod->extable), &mod->num_exentries);
2108
2109	if (section_addr(info, "__obsparm"))
2110	pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2111
2112	info->dyndbg.descs = section_objs(info, "__dyndbg",
2113	sizeof(*info->dyndbg.descs), &info->dyndbg.num_descs);
2114	info->dyndbg.classes = section_objs(info, "__dyndbg_classes",
2115	sizeof(*info->dyndbg.classes), &info->dyndbg.num_classes);
2116
2117	return 0;
2118	}
2119
2120	static int move_module(struct module mod, struct load_info info)
2121	{
2122	int i;
2123	void *ptr;
2124
2125	/* Do the allocs. */
2126	ptr = module_alloc(mod->core_layout.size);
2127	/*
2128	* The pointer to this block is stored in the module structure
2129	* which is inside the block. Just mark it as not being a
2130	* leak.
2131	*/
2132	kmemleak_not_leak(ptr);
2133	if (!ptr)
2134	return -ENOMEM;
2135
2136	memset(ptr, 0, mod->core_layout.size);
2137	mod->core_layout.base = ptr;
2138
2139	if (mod->init_layout.size) {
2140	ptr = module_alloc(mod->init_layout.size);
2141	/*
2142	* The pointer to this block is stored in the module structure
2143	* which is inside the block. This block doesn't need to be
2144	* scanned as it contains data and code that will be freed
2145	* after the module is initialized.
2146	*/
2147	kmemleak_ignore(ptr);
2148	if (!ptr) {
2149	module_memfree(mod->core_layout.base);
2150	return -ENOMEM;
2151	}
2152	memset(ptr, 0, mod->init_layout.size);
2153	mod->init_layout.base = ptr;
2154	} else
2155	mod->init_layout.base = NULL;
2156
2157	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
2158	/* Do the allocs. */
2159	ptr = vzalloc(mod->data_layout.size);
2160	/*
2161	* The pointer to this block is stored in the module structure
2162	* which is inside the block. Just mark it as not being a
2163	* leak.
2164	*/
2165	kmemleak_not_leak(ptr);
2166	if (!ptr) {
2167	module_memfree(mod->core_layout.base);
2168	module_memfree(mod->init_layout.base);
2169	return -ENOMEM;
2170	}
2171
2172	mod->data_layout.base = ptr;
2173	#endif
2174	/* Transfer each section which specifies SHF_ALLOC */
2175	pr_debug("final section addresses:\n");
2176	for (i = 0; i < info->hdr->e_shnum; i++) {
2177	void *dest;
2178	Elf_Shdr *shdr = &info->sechdrs[i];
2179
2180	if (!(shdr->sh_flags & SHF_ALLOC))
2181	continue;
2182
2183	if (shdr->sh_entsize & INIT_OFFSET_MASK)
2184	dest = mod->init_layout.base
2185	+ (shdr->sh_entsize & ~INIT_OFFSET_MASK);
2186	else if (!(shdr->sh_flags & SHF_EXECINSTR))
2187	dest = mod->data_layout.base + shdr->sh_entsize;
2188	else
2189	dest = mod->core_layout.base + shdr->sh_entsize;
2190
2191	if (shdr->sh_type != SHT_NOBITS)
2192	memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2193	/* Update sh_addr to point to copy in image. */
2194	shdr->sh_addr = (unsigned long)dest;
2195	pr_debug("\t0x%lx %s\n",
2196	(long)shdr->sh_addr, info->secstrings + shdr->sh_name);
2197	}
2198
2199	return 0;
2200	}
2201
2202	static int check_module_license_and_versions(struct module *mod)
2203	{
2204	int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
2205
2206	/*
2207	* ndiswrapper is under GPL by itself, but loads proprietary modules.
2208	* Don't use add_taint_module(), as it would prevent ndiswrapper from
2209	* using GPL-only symbols it needs.
2210	*/
2211	if (strcmp(mod->name, "ndiswrapper") == 0)
2212	add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2213
2214	/* driverloader was caught wrongly pretending to be under GPL */
2215	if (strcmp(mod->name, "driverloader") == 0)
2216	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2217	LOCKDEP_NOW_UNRELIABLE);
2218
2219	/* lve claims to be GPL but upstream won't provide source */
2220	if (strcmp(mod->name, "lve") == 0)
2221	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2222	LOCKDEP_NOW_UNRELIABLE);
2223
2224	if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
2225	pr_warn("%s: module license taints kernel.\n", mod->name);
2226
2227	#ifdef CONFIG_MODVERSIONS
2228	if ((mod->num_syms && !mod->crcs) \|\|
2229	(mod->num_gpl_syms && !mod->gpl_crcs)) {
2230	return try_to_force_load(mod,
2231	"no versions for exported symbols");
2232	}
2233	#endif
2234	return 0;
2235	}
2236
2237	static void flush_module_icache(const struct module *mod)
2238	{
2239	/*
2240	* Flush the instruction cache, since we've played with text.
2241	* Do it before processing of module parameters, so the module
2242	* can provide parameter accessor functions of its own.
2243	*/
2244	if (mod->init_layout.base)
2245	flush_icache_range((unsigned long)mod->init_layout.base,
2246	(unsigned long)mod->init_layout.base
2247	+ mod->init_layout.size);
2248	flush_icache_range((unsigned long)mod->core_layout.base,
2249	(unsigned long)mod->core_layout.base + mod->core_layout.size);
2250	}
2251
2252	bool __weak module_elf_check_arch(Elf_Ehdr *hdr)
2253	{
2254	return true;
2255	}
2256
2257	int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2258	Elf_Shdr *sechdrs,
2259	char *secstrings,
2260	struct module *mod)
2261	{
2262	return 0;
2263	}
2264
2265	/* module_blacklist is a comma-separated list of module names */
2266	static char *module_blacklist;
2267	static bool blacklisted(const char *module_name)
2268	{
2269	const char *p;
2270	size_t len;
2271
2272	if (!module_blacklist)
2273	return false;
2274
2275	for (p = module_blacklist; *p; p += len) {
2276	len = strcspn(p, ",");
2277	if (strlen(module_name) == len && !memcmp(module_name, p, len))
2278	return true;
2279	if (p[len] == ',')
2280	len++;
2281	}
2282	return false;
2283	}
2284	core_param(module_blacklist, module_blacklist, charp, 0400);
2285
2286	static struct module layout_and_allocate(struct load_info info, int flags)
2287	{
2288	struct module *mod;
2289	unsigned int ndx;
2290	int err;
2291
2292	err = check_modinfo(info->mod, info, flags);
2293	if (err)
2294	return ERR_PTR(err);
2295
2296	/* Allow arches to frob section contents and sizes. */
2297	err = module_frob_arch_sections(info->hdr, info->sechdrs,
2298	info->secstrings, info->mod);
2299	if (err < 0)
2300	return ERR_PTR(err);
2301
2302	err = module_enforce_rwx_sections(info->hdr, info->sechdrs,
2303	info->secstrings, info->mod);
2304	if (err < 0)
2305	return ERR_PTR(err);
2306
2307	/* We will do a special allocation for per-cpu sections later. */
2308	info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2309
2310	/*
2311	* Mark ro_after_init section with SHF_RO_AFTER_INIT so that
2312	* layout_sections() can put it in the right place.
2313	* Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
2314	*/
2315	ndx = find_sec(info, ".data..ro_after_init");
2316	if (ndx)
2317	info->sechdrs[ndx].sh_flags \|= SHF_RO_AFTER_INIT;
2318	/*
2319	* Mark the __jump_table section as ro_after_init as well: these data
2320	* structures are never modified, with the exception of entries that
2321	* refer to code in the __init section, which are annotated as such
2322	* at module load time.
2323	*/
2324	ndx = find_sec(info, "__jump_table");
2325	if (ndx)
2326	info->sechdrs[ndx].sh_flags \|= SHF_RO_AFTER_INIT;
2327
2328	/*
2329	* Determine total sizes, and put offsets in sh_entsize. For now
2330	* this is done generically; there doesn't appear to be any
2331	* special cases for the architectures.
2332	*/
2333	layout_sections(info->mod, info);
2334	layout_symtab(info->mod, info);
2335
2336	/* Allocate and move to the final place */
2337	err = move_module(info->mod, info);
2338	if (err)
2339	return ERR_PTR(err);
2340
2341	/* Module has been copied to its final place now: return it. */
2342	mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2343	kmemleak_load_module(mod, info);
2344	return mod;
2345	}
2346
2347	/* mod is no longer valid after this! */
2348	static void module_deallocate(struct module mod, struct load_info info)
2349	{
2350	percpu_modfree(mod);
2351	module_arch_freeing_init(mod);
2352	module_memfree(mod->init_layout.base);
2353	module_memfree(mod->core_layout.base);
2354	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
2355	vfree(mod->data_layout.base);
2356	#endif
2357	}
2358
2359	int __weak module_finalize(const Elf_Ehdr *hdr,
2360	const Elf_Shdr *sechdrs,
2361	struct module *me)
2362	{
2363	return 0;
2364	}
2365
2366	static int post_relocation(struct module mod, const struct load_info info)
2367	{
2368	/* Sort exception table now relocations are done. */
2369	sort_extable(mod->extable, mod->extable + mod->num_exentries);
2370
2371	/* Copy relocated percpu area over. */
2372	percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
2373	info->sechdrs[info->index.pcpu].sh_size);
2374
2375	/* Setup kallsyms-specific fields. */
2376	add_kallsyms(mod, info);
2377
2378	/* Arch-specific module finalizing. */
2379	return module_finalize(info->hdr, info->sechdrs, mod);
2380	}
2381
2382	/* Is this module of this name done loading? No locks held. */
2383	static bool finished_loading(const char *name)
2384	{
2385	struct module *mod;
2386	bool ret;
2387
2388	/*
2389	* The module_mutex should not be a heavily contended lock;
2390	* if we get the occasional sleep here, we'll go an extra iteration
2391	* in the wait_event_interruptible(), which is harmless.
2392	*/
2393	sched_annotate_sleep();
2394	mutex_lock(&module_mutex);
2395	mod = find_module_all(name, strlen(name), true);
2396	ret = !mod \|\| mod->state == MODULE_STATE_LIVE
2397	\|\| mod->state == MODULE_STATE_GOING;
2398	mutex_unlock(&module_mutex);
2399
2400	return ret;
2401	}
2402
2403	/* Call module constructors. */
2404	static void do_mod_ctors(struct module *mod)
2405	{
2406	#ifdef CONFIG_CONSTRUCTORS
2407	unsigned long i;
2408
2409	for (i = 0; i < mod->num_ctors; i++)
2410	mod->ctors[i]();
2411	#endif
2412	}
2413
2414	/* For freeing module_init on success, in case kallsyms traversing */
2415	struct mod_initfree {
2416	struct llist_node node;
2417	void *module_init;
2418	};
2419
2420	static void do_free_init(struct work_struct *w)
2421	{
2422	struct llist_node pos, n, *list;
2423	struct mod_initfree *initfree;
2424
2425	list = llist_del_all(&init_free_list);
2426
2427	synchronize_rcu();
2428
2429	llist_for_each_safe(pos, n, list) {
2430	initfree = container_of(pos, struct mod_initfree, node);
2431	module_memfree(initfree->module_init);
2432	kfree(initfree);
2433	}
2434	}
2435
2436	#undef MODULE_PARAM_PREFIX
2437	#define MODULE_PARAM_PREFIX "module."
2438	/* Default value for module->async_probe_requested */
2439	static bool async_probe;
2440	module_param(async_probe, bool, 0644);
2441
2442	/*
2443	* This is where the real work happens.
2444	*
2445	* Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
2446	* helper command 'lx-symbols'.
2447	*/
2448	static noinline int do_init_module(struct module *mod)
2449	{
2450	int ret = 0;
2451	struct mod_initfree *freeinit;
2452
2453	freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
2454	if (!freeinit) {
2455	ret = -ENOMEM;
2456	goto fail;
2457	}
2458	freeinit->module_init = mod->init_layout.base;
2459
2460	do_mod_ctors(mod);
2461	/* Start the module */
2462	if (mod->init != NULL)
2463	ret = do_one_initcall(mod->init);
2464	if (ret < 0) {
2465	goto fail_free_freeinit;
2466	}
2467	if (ret > 0) {
2468	pr_warn("%s: '%s'->init suspiciously returned %d, it should "
2469	"follow 0/-E convention\n"
2470	"%s: loading module anyway...\n",
2471	__func__, mod->name, ret, __func__);
2472	dump_stack();
2473	}
2474
2475	/* Now it's a first class citizen! */
2476	mod->state = MODULE_STATE_LIVE;
2477	blocking_notifier_call_chain(&module_notify_list,
2478	MODULE_STATE_LIVE, mod);
2479
2480	/* Delay uevent until module has finished its init routine */
2481	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
2482
2483	/*
2484	* We need to finish all async code before the module init sequence
2485	* is done. This has potential to deadlock if synchronous module
2486	* loading is requested from async (which is not allowed!).
2487	*
2488	* See commit 0fdff3ec6d87 ("async, kmod: warn on synchronous
2489	* request_module() from async workers") for more details.
2490	*/
2491	if (!mod->async_probe_requested)
2492	async_synchronize_full();
2493
2494	ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base +
2495	mod->init_layout.size);
2496	mutex_lock(&module_mutex);
2497	/* Drop initial reference. */
2498	module_put(mod);
2499	trim_init_extable(mod);
2500	#ifdef CONFIG_KALLSYMS
2501	/* Switch to core kallsyms now init is done: kallsyms may be walking! */
2502	rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
2503	#endif
2504	module_enable_ro(mod, true);
2505	mod_tree_remove_init(mod);
2506	module_arch_freeing_init(mod);
2507	mod->init_layout.base = NULL;
2508	mod->init_layout.size = 0;
2509	mod->init_layout.ro_size = 0;
2510	mod->init_layout.ro_after_init_size = 0;
2511	mod->init_layout.text_size = 0;
2512	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
2513	/* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */
2514	mod->btf_data = NULL;
2515	#endif
2516	/*
2517	* We want to free module_init, but be aware that kallsyms may be
2518	* walking this with preempt disabled. In all the failure paths, we
2519	* call synchronize_rcu(), but we don't want to slow down the success
2520	* path. module_memfree() cannot be called in an interrupt, so do the
2521	* work and call synchronize_rcu() in a work queue.
2522	*
2523	* Note that module_alloc() on most architectures creates W+X page
2524	* mappings which won't be cleaned up until do_free_init() runs. Any
2525	* code such as mark_rodata_ro() which depends on those mappings to
2526	* be cleaned up needs to sync with the queued work - ie
2527	* rcu_barrier()
2528	*/
2529	if (llist_add(&freeinit->node, &init_free_list))
2530	schedule_work(&init_free_wq);
2531
2532	mutex_unlock(&module_mutex);
2533	wake_up_all(&module_wq);
2534
2535	return 0;
2536
2537	fail_free_freeinit:
2538	kfree(freeinit);
2539	fail:
2540	/* Try to protect us from buggy refcounters. */
2541	mod->state = MODULE_STATE_GOING;
2542	synchronize_rcu();
2543	module_put(mod);
2544	blocking_notifier_call_chain(&module_notify_list,
2545	MODULE_STATE_GOING, mod);
2546	klp_module_going(mod);
2547	ftrace_release_mod(mod);
2548	free_module(mod);
2549	wake_up_all(&module_wq);
2550	return ret;
2551	}
2552
2553	static int may_init_module(void)
2554	{
2555	if (!capable(CAP_SYS_MODULE) \|\| modules_disabled)
2556	return -EPERM;
2557
2558	return 0;
2559	}
2560
2561	/*
2562	* We try to place it in the list now to make sure it's unique before
2563	* we dedicate too many resources. In particular, temporary percpu
2564	* memory exhaustion.
2565	*/
2566	static int add_unformed_module(struct module *mod)
2567	{
2568	int err;
2569	struct module *old;
2570
2571	mod->state = MODULE_STATE_UNFORMED;
2572
2573	mutex_lock(&module_mutex);
2574	old = find_module_all(mod->name, strlen(mod->name), true);
2575	if (old != NULL) {
2576	if (old->state == MODULE_STATE_COMING
2577	\|\| old->state == MODULE_STATE_UNFORMED) {
2578	/* Wait in case it fails to load. */
2579	mutex_unlock(&module_mutex);
2580	err = wait_event_interruptible(module_wq,
2581	finished_loading(mod->name));
2582	if (err)
2583	goto out_unlocked;
2584
2585	/* The module might have gone in the meantime. */
2586	mutex_lock(&module_mutex);
2587	old = find_module_all(mod->name, strlen(mod->name),
2588	true);
2589	}
2590
2591	/*
2592	* We are here only when the same module was being loaded. Do
2593	* not try to load it again right now. It prevents long delays
2594	* caused by serialized module load failures. It might happen
2595	* when more devices of the same type trigger load of
2596	* a particular module.
2597	*/
2598	if (old && old->state == MODULE_STATE_LIVE)
2599	err = -EEXIST;
2600	else
2601	err = -EBUSY;
2602	goto out;
2603	}
2604	mod_update_bounds(mod);
2605	list_add_rcu(&mod->list, &modules);
2606	mod_tree_insert(mod);
2607	err = 0;
2608
2609	out:
2610	mutex_unlock(&module_mutex);
2611	out_unlocked:
2612	return err;
2613	}
2614
2615	static int complete_formation(struct module mod, struct load_info info)
2616	{
2617	int err;
2618
2619	mutex_lock(&module_mutex);
2620
2621	/* Find duplicate symbols (must be called under lock). */
2622	err = verify_exported_symbols(mod);
2623	if (err < 0)
2624	goto out;
2625
2626	/* These rely on module_mutex for list integrity. */
2627	module_bug_finalize(info->hdr, info->sechdrs, mod);
2628	module_cfi_finalize(info->hdr, info->sechdrs, mod);
2629
2630	if (module_check_misalignment(mod))
2631	goto out_misaligned;
2632
2633	module_enable_ro(mod, false);
2634	module_enable_nx(mod);
2635	module_enable_x(mod);
2636
2637	/*
2638	* Mark state as coming so strong_try_module_get() ignores us,
2639	* but kallsyms etc. can see us.
2640	*/
2641	mod->state = MODULE_STATE_COMING;
2642	mutex_unlock(&module_mutex);
2643
2644	return 0;
2645
2646	out_misaligned:
2647	err = -EINVAL;
2648	out:
2649	mutex_unlock(&module_mutex);
2650	return err;
2651	}
2652
2653	static int prepare_coming_module(struct module *mod)
2654	{
2655	int err;
2656
2657	ftrace_module_enable(mod);
2658	err = klp_module_coming(mod);
2659	if (err)
2660	return err;
2661
2662	err = blocking_notifier_call_chain_robust(&module_notify_list,
2663	MODULE_STATE_COMING, MODULE_STATE_GOING, mod);
2664	err = notifier_to_errno(err);
2665	if (err)
2666	klp_module_going(mod);
2667
2668	return err;
2669	}
2670
2671	static int unknown_module_param_cb(char param, char val, const char *modname,
2672	void *arg)
2673	{
2674	struct module *mod = arg;
2675	int ret;
2676
2677	if (strcmp(param, "async_probe") == 0) {
2678	if (strtobool(val, &mod->async_probe_requested))
2679	mod->async_probe_requested = true;
2680	return 0;
2681	}
2682
2683	/* Check for magic 'dyndbg' arg */
2684	ret = ddebug_dyndbg_module_param_cb(param, val, modname);
2685	if (ret != 0)
2686	pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
2687	return 0;
2688	}
2689
2690	/*
2691	* Allocate and load the module: note that size of section 0 is always
2692	* zero, and we rely on this for optional sections.
2693	*/
2694	static int load_module(struct load_info info, const char __user uargs,
2695	int flags)
2696	{
2697	struct module *mod;
2698	long err = 0;
2699	char *after_dashes;
2700
2701	/*
2702	* Do the signature check (if any) first. All that
2703	* the signature check needs is info->len, it does
2704	* not need any of the section info. That can be
2705	* set up later. This will minimize the chances
2706	* of a corrupt module causing problems before
2707	* we even get to the signature check.
2708	*
2709	* The check will also adjust info->len by stripping
2710	* off the sig length at the end of the module, making
2711	* checks against info->len more correct.
2712	*/
2713	err = module_sig_check(info, flags);
2714	if (err)
2715	goto free_copy;
2716
2717	/*
2718	* Do basic sanity checks against the ELF header and
2719	* sections.
2720	*/
2721	err = elf_validity_check(info);
2722	if (err)
2723	goto free_copy;
2724
2725	/*
2726	* Everything checks out, so set up the section info
2727	* in the info structure.
2728	*/
2729	err = setup_load_info(info, flags);
2730	if (err)
2731	goto free_copy;
2732
2733	/*
2734	* Now that we know we have the correct module name, check
2735	* if it's blacklisted.
2736	*/
2737	if (blacklisted(info->name)) {
2738	err = -EPERM;
2739	pr_err("Module %s is blacklisted\n", info->name);
2740	goto free_copy;
2741	}
2742
2743	err = rewrite_section_headers(info, flags);
2744	if (err)
2745	goto free_copy;
2746
2747	/* Check module struct version now, before we try to use module. */
2748	if (!check_modstruct_version(info, info->mod)) {
2749	err = -ENOEXEC;
2750	goto free_copy;
2751	}
2752
2753	/* Figure out module layout, and allocate all the memory. */
2754	mod = layout_and_allocate(info, flags);
2755	if (IS_ERR(mod)) {
2756	err = PTR_ERR(mod);
2757	goto free_copy;
2758	}
2759
2760	audit_log_kern_module(mod->name);
2761
2762	/* Reserve our place in the list. */
2763	err = add_unformed_module(mod);
2764	if (err)
2765	goto free_module;
2766
2767	#ifdef CONFIG_MODULE_SIG
2768	mod->sig_ok = info->sig_ok;
2769	if (!mod->sig_ok) {
2770	pr_notice_once("%s: module verification failed: signature "
2771	"and/or required key missing - tainting "
2772	"kernel\n", mod->name);
2773	add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
2774	}
2775	#endif
2776
2777	/* To avoid stressing percpu allocator, do this once we're unique. */
2778	err = percpu_modalloc(mod, info);
2779	if (err)
2780	goto unlink_mod;
2781
2782	/* Now module is in final location, initialize linked lists, etc. */
2783	err = module_unload_init(mod);
2784	if (err)
2785	goto unlink_mod;
2786
2787	init_param_lock(mod);
2788
2789	/*
2790	* Now we've got everything in the final locations, we can
2791	* find optional sections.
2792	*/
2793	err = find_module_sections(mod, info);
2794	if (err)
2795	goto free_unload;
2796
2797	err = check_module_license_and_versions(mod);
2798	if (err)
2799	goto free_unload;
2800
2801	/* Set up MODINFO_ATTR fields */
2802	setup_modinfo(mod, info);
2803
2804	/* Fix up syms, so that st_value is a pointer to location. */
2805	err = simplify_symbols(mod, info);
2806	if (err < 0)
2807	goto free_modinfo;
2808
2809	err = apply_relocations(mod, info);
2810	if (err < 0)
2811	goto free_modinfo;
2812
2813	err = post_relocation(mod, info);
2814	if (err < 0)
2815	goto free_modinfo;
2816
2817	flush_module_icache(mod);
2818
2819	/* Now copy in args */
2820	mod->args = strndup_user(uargs, ~0UL >> 1);
2821	if (IS_ERR(mod->args)) {
2822	err = PTR_ERR(mod->args);
2823	goto free_arch_cleanup;
2824	}
2825
2826	init_build_id(mod, info);
2827	dynamic_debug_setup(mod, &info->dyndbg);
2828
2829	/* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
2830	ftrace_module_init(mod);
2831
2832	/* Finally it's fully formed, ready to start executing. */
2833	err = complete_formation(mod, info);
2834	if (err)
2835	goto ddebug_cleanup;
2836
2837	err = prepare_coming_module(mod);
2838	if (err)
2839	goto bug_cleanup;
2840
2841	mod->async_probe_requested = async_probe;
2842
2843	/* Module is ready to execute: parsing args may do that. */
2844	after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
2845	-32768, 32767, mod,
2846	unknown_module_param_cb);
2847	if (IS_ERR(after_dashes)) {
2848	err = PTR_ERR(after_dashes);
2849	goto coming_cleanup;
2850	} else if (after_dashes) {
2851	pr_warn("%s: parameters '%s' after `--' ignored\n",
2852	mod->name, after_dashes);
2853	}
2854
2855	/* Link in to sysfs. */
2856	err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
2857	if (err < 0)
2858	goto coming_cleanup;
2859
2860	if (is_livepatch_module(mod)) {
2861	err = copy_module_elf(mod, info);
2862	if (err < 0)
2863	goto sysfs_cleanup;
2864	}
2865
2866	/* Get rid of temporary copy. */
2867	free_copy(info, flags);
2868
2869	/* Done! */
2870	trace_module_load(mod);
2871
2872	return do_init_module(mod);
2873
2874	sysfs_cleanup:
2875	mod_sysfs_teardown(mod);
2876	coming_cleanup:
2877	mod->state = MODULE_STATE_GOING;
2878	destroy_params(mod->kp, mod->num_kp);
2879	blocking_notifier_call_chain(&module_notify_list,
2880	MODULE_STATE_GOING, mod);
2881	klp_module_going(mod);
2882	bug_cleanup:
2883	mod->state = MODULE_STATE_GOING;
2884	/* module_bug_cleanup needs module_mutex protection */
2885	mutex_lock(&module_mutex);
2886	module_bug_cleanup(mod);
2887	mutex_unlock(&module_mutex);
2888
2889	ddebug_cleanup:
2890	ftrace_release_mod(mod);
2891	dynamic_debug_remove(mod, &info->dyndbg);
2892	synchronize_rcu();
2893	kfree(mod->args);
2894	free_arch_cleanup:
2895	module_arch_cleanup(mod);
2896	free_modinfo:
2897	free_modinfo(mod);
2898	free_unload:
2899	module_unload_free(mod);
2900	unlink_mod:
2901	mutex_lock(&module_mutex);
2902	/* Unlink carefully: kallsyms could be walking list. */
2903	list_del_rcu(&mod->list);
2904	mod_tree_remove(mod);
2905	wake_up_all(&module_wq);
2906	/* Wait for RCU-sched synchronizing before releasing mod->list. */
2907	synchronize_rcu();
2908	mutex_unlock(&module_mutex);
2909	free_module:
2910	/* Free lock-classes; relies on the preceding sync_rcu() */
2911	lockdep_free_key_range(mod->data_layout.base, mod->data_layout.size);
2912
2913	module_deallocate(mod, info);
2914	free_copy:
2915	free_copy(info, flags);
2916	return err;
2917	}
2918
2919	SYSCALL_DEFINE3(init_module, void __user *, umod,
2920	unsigned long, len, const char __user *, uargs)
2921	{
2922	int err;
2923	struct load_info info = { };
2924
2925	err = may_init_module();
2926	if (err)
2927	return err;
2928
2929	pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
2930	umod, len, uargs);
2931
2932	err = copy_module_from_user(umod, len, &info);
2933	if (err)
2934	return err;
2935
2936	return load_module(&info, uargs, 0);
2937	}
2938
2939	SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
2940	{
2941	struct load_info info = { };
2942	void *buf = NULL;
2943	int len;
2944	int err;
2945
2946	err = may_init_module();
2947	if (err)
2948	return err;
2949
2950	pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
2951
2952	if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
2953	\|MODULE_INIT_IGNORE_VERMAGIC
2954	\|MODULE_INIT_COMPRESSED_FILE))
2955	return -EINVAL;
2956
2957	len = kernel_read_file_from_fd(fd, 0, &buf, INT_MAX, NULL,
2958	READING_MODULE);
2959	if (len < 0)
2960	return len;
2961
2962	if (flags & MODULE_INIT_COMPRESSED_FILE) {
2963	err = module_decompress(&info, buf, len);
2964	vfree(buf); /* compressed data is no longer needed */
2965	if (err)
2966	return err;
2967	} else {
2968	info.hdr = buf;
2969	info.len = len;
2970	}
2971
2972	return load_module(&info, uargs, flags);
2973	}
2974
2975	static inline int within(unsigned long addr, void *start, unsigned long size)
2976	{
2977	return ((void )addr >= start && (void )addr < start + size);
2978	}
2979
2980	/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
2981	char module_flags(struct module mod, char *buf, bool show_state)
2982	{
2983	int bx = 0;
2984
2985	BUG_ON(mod->state == MODULE_STATE_UNFORMED);
2986	if (!mod->taints && !show_state)
2987	goto out;
2988	if (mod->taints \|\|
2989	mod->state == MODULE_STATE_GOING \|\|
2990	mod->state == MODULE_STATE_COMING) {
2991	buf[bx++] = '(';
2992	bx += module_flags_taint(mod->taints, buf + bx);
2993	/* Show a - for module-is-being-unloaded */
2994	if (mod->state == MODULE_STATE_GOING && show_state)
2995	buf[bx++] = '-';
2996	/* Show a + for module-is-being-loaded */
2997	if (mod->state == MODULE_STATE_COMING && show_state)
2998	buf[bx++] = '+';
2999	buf[bx++] = ')';
3000	}
3001	out:
3002	buf[bx] = '\0';
3003
3004	return buf;
3005	}
3006
3007	/* Given an address, look for it in the module exception tables. */
3008	const struct exception_table_entry *search_module_extables(unsigned long addr)
3009	{
3010	const struct exception_table_entry *e = NULL;
3011	struct module *mod;
3012
3013	preempt_disable();
3014	mod = __module_address(addr);
3015	if (!mod)
3016	goto out;
3017
3018	if (!mod->num_exentries)
3019	goto out;
3020
3021	e = search_extable(mod->extable,
3022	mod->num_exentries,
3023	addr);
3024	out:
3025	preempt_enable();
3026
3027	/*
3028	* Now, if we found one, we are running inside it now, hence
3029	* we cannot unload the module, hence no refcnt needed.
3030	*/
3031	return e;
3032	}
3033
3034	/**
3035	* is_module_address() - is this address inside a module?
3036	* @addr: the address to check.
3037	*
3038	* See is_module_text_address() if you simply want to see if the address
3039	* is code (not data).
3040	*/
3041	bool is_module_address(unsigned long addr)
3042	{
3043	bool ret;
3044
3045	preempt_disable();
3046	ret = __module_address(addr) != NULL;
3047	preempt_enable();
3048
3049	return ret;
3050	}
3051
3052	/**
3053	* __module_address() - get the module which contains an address.
3054	* @addr: the address.
3055	*
3056	* Must be called with preempt disabled or module mutex held so that
3057	* module doesn't get freed during this.
3058	*/
3059	struct module *__module_address(unsigned long addr)
3060	{
3061	struct module *mod;
3062	struct mod_tree_root *tree;
3063
3064	if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max)
3065	tree = &mod_tree;
3066	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
3067	else if (addr >= mod_data_tree.addr_min && addr <= mod_data_tree.addr_max)
3068	tree = &mod_data_tree;
3069	#endif
3070	else
3071	return NULL;
3072
3073	module_assert_mutex_or_preempt();
3074
3075	mod = mod_find(addr, tree);
3076	if (mod) {
3077	BUG_ON(!within_module(addr, mod));
3078	if (mod->state == MODULE_STATE_UNFORMED)
3079	mod = NULL;
3080	}
3081	return mod;
3082	}
3083
3084	/**
3085	* is_module_text_address() - is this address inside module code?
3086	* @addr: the address to check.
3087	*
3088	* See is_module_address() if you simply want to see if the address is
3089	* anywhere in a module. See kernel_text_address() for testing if an
3090	* address corresponds to kernel or module code.
3091	*/
3092	bool is_module_text_address(unsigned long addr)
3093	{
3094	bool ret;
3095
3096	preempt_disable();
3097	ret = __module_text_address(addr) != NULL;
3098	preempt_enable();
3099
3100	return ret;
3101	}
3102
3103	/**
3104	* __module_text_address() - get the module whose code contains an address.
3105	* @addr: the address.
3106	*
3107	* Must be called with preempt disabled or module mutex held so that
3108	* module doesn't get freed during this.
3109	*/
3110	struct module *__module_text_address(unsigned long addr)
3111	{
3112	struct module *mod = __module_address(addr);
3113	if (mod) {
3114	/* Make sure it's within the text section. */
3115	if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
3116	&& !within(addr, mod->core_layout.base, mod->core_layout.text_size))
3117	mod = NULL;
3118	}
3119	return mod;
3120	}
3121
3122	/* Don't grab lock, we're oopsing. */
3123	void print_modules(void)
3124	{
3125	struct module *mod;
3126	char buf[MODULE_FLAGS_BUF_SIZE];
3127
3128	printk(KERN_DEFAULT "Modules linked in:");
3129	/* Most callers should already have preempt disabled, but make sure */
3130	preempt_disable();
3131	list_for_each_entry_rcu(mod, &modules, list) {
3132	if (mod->state == MODULE_STATE_UNFORMED)
3133	continue;
3134	pr_cont(" %s%s", mod->name, module_flags(mod, buf, true));
3135	}
3136
3137	print_unloaded_tainted_modules();
3138	preempt_enable();
3139	if (last_unloaded_module.name[0])
3140	pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name,
3141	last_unloaded_module.taints);
3142	pr_cont("\n");
3143	}