linux - kernel/module/main.c

3366 lines · 85.4 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	* Copyright (C) 2023 Luis Chamberlain <[email protected]>
6	*/
7
8	#define INCLUDE_VERMAGIC
9
10	#include <linux/export.h>
11	#include <linux/extable.h>
12	#include <linux/moduleloader.h>
13	#include <linux/module_signature.h>
14	#include <linux/trace_events.h>
15	#include <linux/init.h>
16	#include <linux/kallsyms.h>
17	#include <linux/buildid.h>
18	#include <linux/fs.h>
19	#include <linux/kernel.h>
20	#include <linux/kernel_read_file.h>
21	#include <linux/kstrtox.h>
22	#include <linux/slab.h>
23	#include <linux/vmalloc.h>
24	#include <linux/elf.h>
25	#include <linux/seq_file.h>
26	#include <linux/syscalls.h>
27	#include <linux/fcntl.h>
28	#include <linux/rcupdate.h>
29	#include <linux/capability.h>
30	#include <linux/cpu.h>
31	#include <linux/moduleparam.h>
32	#include <linux/errno.h>
33	#include <linux/err.h>
34	#include <linux/vermagic.h>
35	#include <linux/notifier.h>
36	#include <linux/sched.h>
37	#include <linux/device.h>
38	#include <linux/string.h>
39	#include <linux/mutex.h>
40	#include <linux/rculist.h>
41	#include <linux/uaccess.h>
42	#include <asm/cacheflush.h>
43	#include <linux/set_memory.h>
44	#include <asm/mmu_context.h>
45	#include <linux/license.h>
46	#include <asm/sections.h>
47	#include <linux/tracepoint.h>
48	#include <linux/ftrace.h>
49	#include <linux/livepatch.h>
50	#include <linux/async.h>
51	#include <linux/percpu.h>
52	#include <linux/kmemleak.h>
53	#include <linux/jump_label.h>
54	#include <linux/pfn.h>
55	#include <linux/bsearch.h>
56	#include <linux/dynamic_debug.h>
57	#include <linux/audit.h>
58	#include <linux/cfi.h>
59	#include <linux/debugfs.h>
60	#include <uapi/linux/module.h>
61	#include "internal.h"
62
63	#define CREATE_TRACE_POINTS
64	#include <trace/events/module.h>
65
66	/*
67	* Mutex protects:
68	* 1) List of modules (also safely readable with preempt_disable),
69	* 2) module_use links,
70	* 3) mod_tree.addr_min/mod_tree.addr_max.
71	* (delete and add uses RCU list operations).
72	*/
73	DEFINE_MUTEX(module_mutex);
74	LIST_HEAD(modules);
75
76	/* Work queue for freeing init sections in success case */
77	static void do_free_init(struct work_struct *w);
78	static DECLARE_WORK(init_free_wq, do_free_init);
79	static LLIST_HEAD(init_free_list);
80
81	struct mod_tree_root mod_tree __cacheline_aligned = {
82	.addr_min = -1UL,
83	};
84
85	struct symsearch {
86	const struct kernel_symbol start, stop;
87	const s32 *crcs;
88	enum mod_license license;
89	};
90
91	/*
92	* Bounds of module memory, for speeding up __module_address.
93	* Protected by module_mutex.
94	*/
95	static void __mod_update_bounds(enum mod_mem_type type __maybe_unused, void *base,
96	unsigned int size, struct mod_tree_root *tree)
97	{
98	unsigned long min = (unsigned long)base;
99	unsigned long max = min + size;
100
101	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
102	if (mod_mem_type_is_core_data(type)) {
103	if (min < tree->data_addr_min)
104	tree->data_addr_min = min;
105	if (max > tree->data_addr_max)
106	tree->data_addr_max = max;
107	return;
108	}
109	#endif
110	if (min < tree->addr_min)
111	tree->addr_min = min;
112	if (max > tree->addr_max)
113	tree->addr_max = max;
114	}
115
116	static void mod_update_bounds(struct module *mod)
117	{
118	for_each_mod_mem_type(type) {
119	struct module_memory *mod_mem = &mod->mem[type];
120
121	if (mod_mem->size)
122	__mod_update_bounds(type, mod_mem->base, mod_mem->size, &mod_tree);
123	}
124	}
125
126	/* Block module loading/unloading? */
127	int modules_disabled;
128	core_param(nomodule, modules_disabled, bint, 0);
129
130	/* Waiting for a module to finish initializing? */
131	static DECLARE_WAIT_QUEUE_HEAD(module_wq);
132
133	static BLOCKING_NOTIFIER_HEAD(module_notify_list);
134
135	int register_module_notifier(struct notifier_block *nb)
136	{
137	return blocking_notifier_chain_register(&module_notify_list, nb);
138	}
139	EXPORT_SYMBOL(register_module_notifier);
140
141	int unregister_module_notifier(struct notifier_block *nb)
142	{
143	return blocking_notifier_chain_unregister(&module_notify_list, nb);
144	}
145	EXPORT_SYMBOL(unregister_module_notifier);
146
147	/*
148	* We require a truly strong try_module_get(): 0 means success.
149	* Otherwise an error is returned due to ongoing or failed
150	* initialization etc.
151	*/
152	static inline int strong_try_module_get(struct module *mod)
153	{
154	BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
155	if (mod && mod->state == MODULE_STATE_COMING)
156	return -EBUSY;
157	if (try_module_get(mod))
158	return 0;
159	else
160	return -ENOENT;
161	}
162
163	static inline void add_taint_module(struct module *mod, unsigned flag,
164	enum lockdep_ok lockdep_ok)
165	{
166	add_taint(flag, lockdep_ok);
167	set_bit(flag, &mod->taints);
168	}
169
170	/*
171	* A thread that wants to hold a reference to a module only while it
172	* is running can call this to safely exit.
173	*/
174	void __noreturn __module_put_and_kthread_exit(struct module *mod, long code)
175	{
176	module_put(mod);
177	kthread_exit(code);
178	}
179	EXPORT_SYMBOL(__module_put_and_kthread_exit);
180
181	/* Find a module section: 0 means not found. */
182	static unsigned int find_sec(const struct load_info info, const char name)
183	{
184	unsigned int i;
185
186	for (i = 1; i < info->hdr->e_shnum; i++) {
187	Elf_Shdr *shdr = &info->sechdrs[i];
188	/* Alloc bit cleared means "ignore it." */
189	if ((shdr->sh_flags & SHF_ALLOC)
190	&& strcmp(info->secstrings + shdr->sh_name, name) == 0)
191	return i;
192	}
193	return 0;
194	}
195
196	/* Find a module section, or NULL. */
197	static void section_addr(const struct load_info info, const char *name)
198	{
199	/* Section 0 has sh_addr 0. */
200	return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
201	}
202
203	/* Find a module section, or NULL. Fill in number of "objects" in section. */
204	static void section_objs(const struct load_info info,
205	const char *name,
206	size_t object_size,
207	unsigned int *num)
208	{
209	unsigned int sec = find_sec(info, name);
210
211	/* Section 0 has sh_addr 0 and sh_size 0. */
212	*num = info->sechdrs[sec].sh_size / object_size;
213	return (void *)info->sechdrs[sec].sh_addr;
214	}
215
216	/* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */
217	static unsigned int find_any_sec(const struct load_info info, const char name)
218	{
219	unsigned int i;
220
221	for (i = 1; i < info->hdr->e_shnum; i++) {
222	Elf_Shdr *shdr = &info->sechdrs[i];
223	if (strcmp(info->secstrings + shdr->sh_name, name) == 0)
224	return i;
225	}
226	return 0;
227	}
228
229	/*
230	* Find a module section, or NULL. Fill in number of "objects" in section.
231	* Ignores SHF_ALLOC flag.
232	*/
233	static __maybe_unused void any_section_objs(const struct load_info info,
234	const char *name,
235	size_t object_size,
236	unsigned int *num)
237	{
238	unsigned int sec = find_any_sec(info, name);
239
240	/* Section 0 has sh_addr 0 and sh_size 0. */
241	*num = info->sechdrs[sec].sh_size / object_size;
242	return (void *)info->sechdrs[sec].sh_addr;
243	}
244
245	#ifndef CONFIG_MODVERSIONS
246	#define symversion(base, idx) NULL
247	#else
248	#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
249	#endif
250
251	static const char kernel_symbol_name(const struct kernel_symbol sym)
252	{
253	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
254	return offset_to_ptr(&sym->name_offset);
255	#else
256	return sym->name;
257	#endif
258	}
259
260	static const char kernel_symbol_namespace(const struct kernel_symbol sym)
261	{
262	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
263	if (!sym->namespace_offset)
264	return NULL;
265	return offset_to_ptr(&sym->namespace_offset);
266	#else
267	return sym->namespace;
268	#endif
269	}
270
271	int cmp_name(const void name, const void sym)
272	{
273	return strcmp(name, kernel_symbol_name(sym));
274	}
275
276	static bool find_exported_symbol_in_section(const struct symsearch *syms,
277	struct module *owner,
278	struct find_symbol_arg *fsa)
279	{
280	struct kernel_symbol *sym;
281
282	if (!fsa->gplok && syms->license == GPL_ONLY)
283	return false;
284
285	sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
286	sizeof(struct kernel_symbol), cmp_name);
287	if (!sym)
288	return false;
289
290	fsa->owner = owner;
291	fsa->crc = symversion(syms->crcs, sym - syms->start);
292	fsa->sym = sym;
293	fsa->license = syms->license;
294
295	return true;
296	}
297
298	/*
299	* Find an exported symbol and return it, along with, (optional) crc and
300	* (optional) module which owns it. Needs preempt disabled or module_mutex.
301	*/
302	bool find_symbol(struct find_symbol_arg *fsa)
303	{
304	static const struct symsearch arr[] = {
305	{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
306	NOT_GPL_ONLY },
307	{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
308	__start___kcrctab_gpl,
309	GPL_ONLY },
310	};
311	struct module *mod;
312	unsigned int i;
313
314	module_assert_mutex_or_preempt();
315
316	for (i = 0; i < ARRAY_SIZE(arr); i++)
317	if (find_exported_symbol_in_section(&arr[i], NULL, fsa))
318	return true;
319
320	list_for_each_entry_rcu(mod, &modules, list,
321	lockdep_is_held(&module_mutex)) {
322	struct symsearch arr[] = {
323	{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
324	NOT_GPL_ONLY },
325	{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
326	mod->gpl_crcs,
327	GPL_ONLY },
328	};
329
330	if (mod->state == MODULE_STATE_UNFORMED)
331	continue;
332
333	for (i = 0; i < ARRAY_SIZE(arr); i++)
334	if (find_exported_symbol_in_section(&arr[i], mod, fsa))
335	return true;
336	}
337
338	pr_debug("Failed to find symbol %s\n", fsa->name);
339	return false;
340	}
341
342	/*
343	* Search for module by name: must hold module_mutex (or preempt disabled
344	* for read-only access).
345	*/
346	struct module find_module_all(const char name, size_t len,
347	bool even_unformed)
348	{
349	struct module *mod;
350
351	module_assert_mutex_or_preempt();
352
353	list_for_each_entry_rcu(mod, &modules, list,
354	lockdep_is_held(&module_mutex)) {
355	if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
356	continue;
357	if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
358	return mod;
359	}
360	return NULL;
361	}
362
363	struct module find_module(const char name)
364	{
365	return find_module_all(name, strlen(name), false);
366	}
367
368	#ifdef CONFIG_SMP
369
370	static inline void __percpu mod_percpu(struct module mod)
371	{
372	return mod->percpu;
373	}
374
375	static int percpu_modalloc(struct module mod, struct load_info info)
376	{
377	Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
378	unsigned long align = pcpusec->sh_addralign;
379
380	if (!pcpusec->sh_size)
381	return 0;
382
383	if (align > PAGE_SIZE) {
384	pr_warn("%s: per-cpu alignment %li > %li\n",
385	mod->name, align, PAGE_SIZE);
386	align = PAGE_SIZE;
387	}
388
389	mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
390	if (!mod->percpu) {
391	pr_warn("%s: Could not allocate %lu bytes percpu data\n",
392	mod->name, (unsigned long)pcpusec->sh_size);
393	return -ENOMEM;
394	}
395	mod->percpu_size = pcpusec->sh_size;
396	return 0;
397	}
398
399	static void percpu_modfree(struct module *mod)
400	{
401	free_percpu(mod->percpu);
402	}
403
404	static unsigned int find_pcpusec(struct load_info *info)
405	{
406	return find_sec(info, ".data..percpu");
407	}
408
409	static void percpu_modcopy(struct module *mod,
410	const void *from, unsigned long size)
411	{
412	int cpu;
413
414	for_each_possible_cpu(cpu)
415	memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
416	}
417
418	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
419	{
420	struct module *mod;
421	unsigned int cpu;
422
423	preempt_disable();
424
425	list_for_each_entry_rcu(mod, &modules, list) {
426	if (mod->state == MODULE_STATE_UNFORMED)
427	continue;
428	if (!mod->percpu_size)
429	continue;
430	for_each_possible_cpu(cpu) {
431	void *start = per_cpu_ptr(mod->percpu, cpu);
432	void va = (void )addr;
433
434	if (va >= start && va < start + mod->percpu_size) {
435	if (can_addr) {
436	*can_addr = (unsigned long) (va - start);
437	*can_addr += (unsigned long)
438	per_cpu_ptr(mod->percpu,
439	get_boot_cpu_id());
440	}
441	preempt_enable();
442	return true;
443	}
444	}
445	}
446
447	preempt_enable();
448	return false;
449	}
450
451	/**
452	* is_module_percpu_address() - test whether address is from module static percpu
453	* @addr: address to test
454	*
455	* Test whether @addr belongs to module static percpu area.
456	*
457	* Return: %true if @addr is from module static percpu area
458	*/
459	bool is_module_percpu_address(unsigned long addr)
460	{
461	return __is_module_percpu_address(addr, NULL);
462	}
463
464	#else /* ... !CONFIG_SMP */
465
466	static inline void __percpu mod_percpu(struct module mod)
467	{
468	return NULL;
469	}
470	static int percpu_modalloc(struct module mod, struct load_info info)
471	{
472	/* UP modules shouldn't have this section: ENOMEM isn't quite right */
473	if (info->sechdrs[info->index.pcpu].sh_size != 0)
474	return -ENOMEM;
475	return 0;
476	}
477	static inline void percpu_modfree(struct module *mod)
478	{
479	}
480	static unsigned int find_pcpusec(struct load_info *info)
481	{
482	return 0;
483	}
484	static inline void percpu_modcopy(struct module *mod,
485	const void *from, unsigned long size)
486	{
487	/* pcpusec should be 0, and size of that section should be 0. */
488	BUG_ON(size != 0);
489	}
490	bool is_module_percpu_address(unsigned long addr)
491	{
492	return false;
493	}
494
495	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
496	{
497	return false;
498	}
499
500	#endif /* CONFIG_SMP */
501
502	#define MODINFO_ATTR(field) \
503	static void setup_modinfo_##field(struct module mod, const char s) \
504	{ \
505	mod->field = kstrdup(s, GFP_KERNEL); \
506	} \
507	static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
508	struct module_kobject mk, char buffer) \
509	{ \
510	return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
511	} \
512	static int modinfo_##field##_exists(struct module *mod) \
513	{ \
514	return mod->field != NULL; \
515	} \
516	static void free_modinfo_##field(struct module *mod) \
517	{ \
518	kfree(mod->field); \
519	mod->field = NULL; \
520	} \
521	static struct module_attribute modinfo_##field = { \
522	.attr = { .name = __stringify(field), .mode = 0444 }, \
523	.show = show_modinfo_##field, \
524	.setup = setup_modinfo_##field, \
525	.test = modinfo_##field##_exists, \
526	.free = free_modinfo_##field, \
527	};
528
529	MODINFO_ATTR(version);
530	MODINFO_ATTR(srcversion);
531
532	static struct {
533	char name[MODULE_NAME_LEN + 1];
534	char taints[MODULE_FLAGS_BUF_SIZE];
535	} last_unloaded_module;
536
537	#ifdef CONFIG_MODULE_UNLOAD
538
539	EXPORT_TRACEPOINT_SYMBOL(module_get);
540
541	/* MODULE_REF_BASE is the base reference count by kmodule loader. */
542	#define MODULE_REF_BASE 1
543
544	/* Init the unload section of the module. */
545	static int module_unload_init(struct module *mod)
546	{
547	/*
548	* Initialize reference counter to MODULE_REF_BASE.
549	* refcnt == 0 means module is going.
550	*/
551	atomic_set(&mod->refcnt, MODULE_REF_BASE);
552
553	INIT_LIST_HEAD(&mod->source_list);
554	INIT_LIST_HEAD(&mod->target_list);
555
556	/* Hold reference count during initialization. */
557	atomic_inc(&mod->refcnt);
558
559	return 0;
560	}
561
562	/* Does a already use b? */
563	static int already_uses(struct module a, struct module b)
564	{
565	struct module_use *use;
566
567	list_for_each_entry(use, &b->source_list, source_list) {
568	if (use->source == a)
569	return 1;
570	}
571	pr_debug("%s does not use %s!\n", a->name, b->name);
572	return 0;
573	}
574
575	/*
576	* Module a uses b
577	* - we add 'a' as a "source", 'b' as a "target" of module use
578	* - the module_use is added to the list of 'b' sources (so
579	* 'b' can walk the list to see who sourced them), and of 'a'
580	* targets (so 'a' can see what modules it targets).
581	*/
582	static int add_module_usage(struct module a, struct module b)
583	{
584	struct module_use *use;
585
586	pr_debug("Allocating new usage for %s.\n", a->name);
587	use = kmalloc(sizeof(*use), GFP_ATOMIC);
588	if (!use)
589	return -ENOMEM;
590
591	use->source = a;
592	use->target = b;
593	list_add(&use->source_list, &b->source_list);
594	list_add(&use->target_list, &a->target_list);
595	return 0;
596	}
597
598	/* Module a uses b: caller needs module_mutex() */
599	static int ref_module(struct module a, struct module b)
600	{
601	int err;
602
603	if (b == NULL \|\| already_uses(a, b))
604	return 0;
605
606	/* If module isn't available, we fail. */
607	err = strong_try_module_get(b);
608	if (err)
609	return err;
610
611	err = add_module_usage(a, b);
612	if (err) {
613	module_put(b);
614	return err;
615	}
616	return 0;
617	}
618
619	/* Clear the unload stuff of the module. */
620	static void module_unload_free(struct module *mod)
621	{
622	struct module_use use, tmp;
623
624	mutex_lock(&module_mutex);
625	list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
626	struct module *i = use->target;
627	pr_debug("%s unusing %s\n", mod->name, i->name);
628	module_put(i);
629	list_del(&use->source_list);
630	list_del(&use->target_list);
631	kfree(use);
632	}
633	mutex_unlock(&module_mutex);
634	}
635
636	#ifdef CONFIG_MODULE_FORCE_UNLOAD
637	static inline int try_force_unload(unsigned int flags)
638	{
639	int ret = (flags & O_TRUNC);
640	if (ret)
641	add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
642	return ret;
643	}
644	#else
645	static inline int try_force_unload(unsigned int flags)
646	{
647	return 0;
648	}
649	#endif /* CONFIG_MODULE_FORCE_UNLOAD */
650
651	/* Try to release refcount of module, 0 means success. */
652	static int try_release_module_ref(struct module *mod)
653	{
654	int ret;
655
656	/* Try to decrement refcnt which we set at loading */
657	ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
658	BUG_ON(ret < 0);
659	if (ret)
660	/* Someone can put this right now, recover with checking */
661	ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
662
663	return ret;
664	}
665
666	static int try_stop_module(struct module mod, int flags, int forced)
667	{
668	/* If it's not unused, quit unless we're forcing. */
669	if (try_release_module_ref(mod) != 0) {
670	*forced = try_force_unload(flags);
671	if (!(*forced))
672	return -EWOULDBLOCK;
673	}
674
675	/* Mark it as dying. */
676	mod->state = MODULE_STATE_GOING;
677
678	return 0;
679	}
680
681	/**
682	* module_refcount() - return the refcount or -1 if unloading
683	* @mod: the module we're checking
684	*
685	* Return:
686	* -1 if the module is in the process of unloading
687	* otherwise the number of references in the kernel to the module
688	*/
689	int module_refcount(struct module *mod)
690	{
691	return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
692	}
693	EXPORT_SYMBOL(module_refcount);
694
695	/* This exists whether we can unload or not */
696	static void free_module(struct module *mod);
697
698	SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
699	unsigned int, flags)
700	{
701	struct module *mod;
702	char name[MODULE_NAME_LEN];
703	char buf[MODULE_FLAGS_BUF_SIZE];
704	int ret, forced = 0;
705
706	if (!capable(CAP_SYS_MODULE) \|\| modules_disabled)
707	return -EPERM;
708
709	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
710	return -EFAULT;
711	name[MODULE_NAME_LEN-1] = '\0';
712
713	audit_log_kern_module(name);
714
715	if (mutex_lock_interruptible(&module_mutex) != 0)
716	return -EINTR;
717
718	mod = find_module(name);
719	if (!mod) {
720	ret = -ENOENT;
721	goto out;
722	}
723
724	if (!list_empty(&mod->source_list)) {
725	/* Other modules depend on us: get rid of them first. */
726	ret = -EWOULDBLOCK;
727	goto out;
728	}
729
730	/* Doing init or already dying? */
731	if (mod->state != MODULE_STATE_LIVE) {
732	/* FIXME: if (force), slam module count damn the torpedoes */
733	pr_debug("%s already dying\n", mod->name);
734	ret = -EBUSY;
735	goto out;
736	}
737
738	/* If it has an init func, it must have an exit func to unload */
739	if (mod->init && !mod->exit) {
740	forced = try_force_unload(flags);
741	if (!forced) {
742	/* This module can't be removed */
743	ret = -EBUSY;
744	goto out;
745	}
746	}
747
748	ret = try_stop_module(mod, flags, &forced);
749	if (ret != 0)
750	goto out;
751
752	mutex_unlock(&module_mutex);
753	/* Final destruction now no one is using it. */
754	if (mod->exit != NULL)
755	mod->exit();
756	blocking_notifier_call_chain(&module_notify_list,
757	MODULE_STATE_GOING, mod);
758	klp_module_going(mod);
759	ftrace_release_mod(mod);
760
761	async_synchronize_full();
762
763	/* Store the name and taints of the last unloaded module for diagnostic purposes */
764	strscpy(last_unloaded_module.name, mod->name, sizeof(last_unloaded_module.name));
765	strscpy(last_unloaded_module.taints, module_flags(mod, buf, false), sizeof(last_unloaded_module.taints));
766
767	free_module(mod);
768	/* someone could wait for the module in add_unformed_module() */
769	wake_up_all(&module_wq);
770	return 0;
771	out:
772	mutex_unlock(&module_mutex);
773	return ret;
774	}
775
776	void __symbol_put(const char *symbol)
777	{
778	struct find_symbol_arg fsa = {
779	.name = symbol,
780	.gplok = true,
781	};
782
783	preempt_disable();
784	BUG_ON(!find_symbol(&fsa));
785	module_put(fsa.owner);
786	preempt_enable();
787	}
788	EXPORT_SYMBOL(__symbol_put);
789
790	/* Note this assumes addr is a function, which it currently always is. */
791	void symbol_put_addr(void *addr)
792	{
793	struct module *modaddr;
794	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
795
796	if (core_kernel_text(a))
797	return;
798
799	/*
800	* Even though we hold a reference on the module; we still need to
801	* disable preemption in order to safely traverse the data structure.
802	*/
803	preempt_disable();
804	modaddr = __module_text_address(a);
805	BUG_ON(!modaddr);
806	module_put(modaddr);
807	preempt_enable();
808	}
809	EXPORT_SYMBOL_GPL(symbol_put_addr);
810
811	static ssize_t show_refcnt(struct module_attribute *mattr,
812	struct module_kobject mk, char buffer)
813	{
814	return sprintf(buffer, "%i\n", module_refcount(mk->mod));
815	}
816
817	static struct module_attribute modinfo_refcnt =
818	__ATTR(refcnt, 0444, show_refcnt, NULL);
819
820	void __module_get(struct module *module)
821	{
822	if (module) {
823	atomic_inc(&module->refcnt);
824	trace_module_get(module, _RET_IP_);
825	}
826	}
827	EXPORT_SYMBOL(__module_get);
828
829	bool try_module_get(struct module *module)
830	{
831	bool ret = true;
832
833	if (module) {
834	/* Note: here, we can fail to get a reference */
835	if (likely(module_is_live(module) &&
836	atomic_inc_not_zero(&module->refcnt) != 0))
837	trace_module_get(module, _RET_IP_);
838	else
839	ret = false;
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	ret = atomic_dec_if_positive(&module->refcnt);
851	WARN_ON(ret < 0); /* Failed to put refcount */
852	trace_module_put(module, _RET_IP_);
853	}
854	}
855	EXPORT_SYMBOL(module_put);
856
857	#else /* !CONFIG_MODULE_UNLOAD */
858	static inline void module_unload_free(struct module *mod)
859	{
860	}
861
862	static int ref_module(struct module a, struct module b)
863	{
864	return strong_try_module_get(b);
865	}
866
867	static inline int module_unload_init(struct module *mod)
868	{
869	return 0;
870	}
871	#endif /* CONFIG_MODULE_UNLOAD */
872
873	size_t module_flags_taint(unsigned long taints, char *buf)
874	{
875	size_t l = 0;
876	int i;
877
878	for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
879	if (taint_flags[i].module && test_bit(i, &taints))
880	buf[l++] = taint_flags[i].c_true;
881	}
882
883	return l;
884	}
885
886	static ssize_t show_initstate(struct module_attribute *mattr,
887	struct module_kobject mk, char buffer)
888	{
889	const char *state = "unknown";
890
891	switch (mk->mod->state) {
892	case MODULE_STATE_LIVE:
893	state = "live";
894	break;
895	case MODULE_STATE_COMING:
896	state = "coming";
897	break;
898	case MODULE_STATE_GOING:
899	state = "going";
900	break;
901	default:
902	BUG();
903	}
904	return sprintf(buffer, "%s\n", state);
905	}
906
907	static struct module_attribute modinfo_initstate =
908	__ATTR(initstate, 0444, show_initstate, NULL);
909
910	static ssize_t store_uevent(struct module_attribute *mattr,
911	struct module_kobject *mk,
912	const char *buffer, size_t count)
913	{
914	int rc;
915
916	rc = kobject_synth_uevent(&mk->kobj, buffer, count);
917	return rc ? rc : count;
918	}
919
920	struct module_attribute module_uevent =
921	__ATTR(uevent, 0200, NULL, store_uevent);
922
923	static ssize_t show_coresize(struct module_attribute *mattr,
924	struct module_kobject mk, char buffer)
925	{
926	unsigned int size = mk->mod->mem[MOD_TEXT].size;
927
928	if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) {
929	for_class_mod_mem_type(type, core_data)
930	size += mk->mod->mem[type].size;
931	}
932	return sprintf(buffer, "%u\n", size);
933	}
934
935	static struct module_attribute modinfo_coresize =
936	__ATTR(coresize, 0444, show_coresize, NULL);
937
938	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
939	static ssize_t show_datasize(struct module_attribute *mattr,
940	struct module_kobject mk, char buffer)
941	{
942	unsigned int size = 0;
943
944	for_class_mod_mem_type(type, core_data)
945	size += mk->mod->mem[type].size;
946	return sprintf(buffer, "%u\n", size);
947	}
948
949	static struct module_attribute modinfo_datasize =
950	__ATTR(datasize, 0444, show_datasize, NULL);
951	#endif
952
953	static ssize_t show_initsize(struct module_attribute *mattr,
954	struct module_kobject mk, char buffer)
955	{
956	unsigned int size = 0;
957
958	for_class_mod_mem_type(type, init)
959	size += mk->mod->mem[type].size;
960	return sprintf(buffer, "%u\n", size);
961	}
962
963	static struct module_attribute modinfo_initsize =
964	__ATTR(initsize, 0444, show_initsize, NULL);
965
966	static ssize_t show_taint(struct module_attribute *mattr,
967	struct module_kobject mk, char buffer)
968	{
969	size_t l;
970
971	l = module_flags_taint(mk->mod->taints, buffer);
972	buffer[l++] = '\n';
973	return l;
974	}
975
976	static struct module_attribute modinfo_taint =
977	__ATTR(taint, 0444, show_taint, NULL);
978
979	struct module_attribute *modinfo_attrs[] = {
980	&module_uevent,
981	&modinfo_version,
982	&modinfo_srcversion,
983	&modinfo_initstate,
984	&modinfo_coresize,
985	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
986	&modinfo_datasize,
987	#endif
988	&modinfo_initsize,
989	&modinfo_taint,
990	#ifdef CONFIG_MODULE_UNLOAD
991	&modinfo_refcnt,
992	#endif
993	NULL,
994	};
995
996	size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);
997
998	static const char vermagic[] = VERMAGIC_STRING;
999
1000	int try_to_force_load(struct module mod, const char reason)
1001	{
1002	#ifdef CONFIG_MODULE_FORCE_LOAD
1003	if (!test_taint(TAINT_FORCED_MODULE))
1004	pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1005	add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
1006	return 0;
1007	#else
1008	return -ENOEXEC;
1009	#endif
1010	}
1011
1012	/* Parse tag=value strings from .modinfo section */
1013	char module_next_tag_pair(char string, unsigned long *secsize)
1014	{
1015	/* Skip non-zero chars */
1016	while (string[0]) {
1017	string++;
1018	if ((*secsize)-- <= 1)
1019	return NULL;
1020	}
1021
1022	/* Skip any zero padding. */
1023	while (!string[0]) {
1024	string++;
1025	if ((*secsize)-- <= 1)
1026	return NULL;
1027	}
1028	return string;
1029	}
1030
1031	static char get_next_modinfo(const struct load_info info, const char *tag,
1032	char *prev)
1033	{
1034	char *p;
1035	unsigned int taglen = strlen(tag);
1036	Elf_Shdr *infosec = &info->sechdrs[info->index.info];
1037	unsigned long size = infosec->sh_size;
1038
1039	/*
1040	* get_modinfo() calls made before rewrite_section_headers()
1041	* must use sh_offset, as sh_addr isn't set!
1042	*/
1043	char modinfo = (char )info->hdr + infosec->sh_offset;
1044
1045	if (prev) {
1046	size -= prev - modinfo;
1047	modinfo = module_next_tag_pair(prev, &size);
1048	}
1049
1050	for (p = modinfo; p; p = module_next_tag_pair(p, &size)) {
1051	if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1052	return p + taglen + 1;
1053	}
1054	return NULL;
1055	}
1056
1057	static char get_modinfo(const struct load_info info, const char *tag)
1058	{
1059	return get_next_modinfo(info, tag, NULL);
1060	}
1061
1062	static int verify_namespace_is_imported(const struct load_info *info,
1063	const struct kernel_symbol *sym,
1064	struct module *mod)
1065	{
1066	const char *namespace;
1067	char *imported_namespace;
1068
1069	namespace = kernel_symbol_namespace(sym);
1070	if (namespace && namespace[0]) {
1071	for_each_modinfo_entry(imported_namespace, info, "import_ns") {
1072	if (strcmp(namespace, imported_namespace) == 0)
1073	return 0;
1074	}
1075	#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1076	pr_warn(
1077	#else
1078	pr_err(
1079	#endif
1080	"%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1081	mod->name, kernel_symbol_name(sym), namespace);
1082	#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1083	return -EINVAL;
1084	#endif
1085	}
1086	return 0;
1087	}
1088
1089	static bool inherit_taint(struct module mod, struct module owner, const char *name)
1090	{
1091	if (!owner \|\| !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
1092	return true;
1093
1094	if (mod->using_gplonly_symbols) {
1095	pr_err("%s: module using GPL-only symbols uses symbols %s from proprietary module %s.\n",
1096	mod->name, name, owner->name);
1097	return false;
1098	}
1099
1100	if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
1101	pr_warn("%s: module uses symbols %s from proprietary module %s, inheriting taint.\n",
1102	mod->name, name, owner->name);
1103	set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
1104	}
1105	return true;
1106	}
1107
1108	/* Resolve a symbol for this module. I.e. if we find one, record usage. */
1109	static const struct kernel_symbol resolve_symbol(struct module mod,
1110	const struct load_info *info,
1111	const char *name,
1112	char ownername[])
1113	{
1114	struct find_symbol_arg fsa = {
1115	.name = name,
1116	.gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
1117	.warn = true,
1118	};
1119	int err;
1120
1121	/*
1122	* The module_mutex should not be a heavily contended lock;
1123	* if we get the occasional sleep here, we'll go an extra iteration
1124	* in the wait_event_interruptible(), which is harmless.
1125	*/
1126	sched_annotate_sleep();
1127	mutex_lock(&module_mutex);
1128	if (!find_symbol(&fsa))
1129	goto unlock;
1130
1131	if (fsa.license == GPL_ONLY)
1132	mod->using_gplonly_symbols = true;
1133
1134	if (!inherit_taint(mod, fsa.owner, name)) {
1135	fsa.sym = NULL;
1136	goto getname;
1137	}
1138
1139	if (!check_version(info, name, mod, fsa.crc)) {
1140	fsa.sym = ERR_PTR(-EINVAL);
1141	goto getname;
1142	}
1143
1144	err = verify_namespace_is_imported(info, fsa.sym, mod);
1145	if (err) {
1146	fsa.sym = ERR_PTR(err);
1147	goto getname;
1148	}
1149
1150	err = ref_module(mod, fsa.owner);
1151	if (err) {
1152	fsa.sym = ERR_PTR(err);
1153	goto getname;
1154	}
1155
1156	getname:
1157	/* We must make copy under the lock if we failed to get ref. */
1158	strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
1159	unlock:
1160	mutex_unlock(&module_mutex);
1161	return fsa.sym;
1162	}
1163
1164	static const struct kernel_symbol *
1165	resolve_symbol_wait(struct module *mod,
1166	const struct load_info *info,
1167	const char *name)
1168	{
1169	const struct kernel_symbol *ksym;
1170	char owner[MODULE_NAME_LEN];
1171
1172	if (wait_event_interruptible_timeout(module_wq,
1173	!IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1174	\|\| PTR_ERR(ksym) != -EBUSY,
1175	30 * HZ) <= 0) {
1176	pr_warn("%s: gave up waiting for init of module %s.\n",
1177	mod->name, owner);
1178	}
1179	return ksym;
1180	}
1181
1182	void __weak module_memfree(void *module_region)
1183	{
1184	/*
1185	* This memory may be RO, and freeing RO memory in an interrupt is not
1186	* supported by vmalloc.
1187	*/
1188	WARN_ON(in_interrupt());
1189	vfree(module_region);
1190	}
1191
1192	void __weak module_arch_cleanup(struct module *mod)
1193	{
1194	}
1195
1196	void __weak module_arch_freeing_init(struct module *mod)
1197	{
1198	}
1199
1200	static bool mod_mem_use_vmalloc(enum mod_mem_type type)
1201	{
1202	return IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC) &&
1203	mod_mem_type_is_core_data(type);
1204	}
1205
1206	static void *module_memory_alloc(unsigned int size, enum mod_mem_type type)
1207	{
1208	if (mod_mem_use_vmalloc(type))
1209	return vzalloc(size);
1210	return module_alloc(size);
1211	}
1212
1213	static void module_memory_free(void *ptr, enum mod_mem_type type)
1214	{
1215	if (mod_mem_use_vmalloc(type))
1216	vfree(ptr);
1217	else
1218	module_memfree(ptr);
1219	}
1220
1221	static void free_mod_mem(struct module *mod)
1222	{
1223	for_each_mod_mem_type(type) {
1224	struct module_memory *mod_mem = &mod->mem[type];
1225
1226	if (type == MOD_DATA)
1227	continue;
1228
1229	/* Free lock-classes; relies on the preceding sync_rcu(). */
1230	lockdep_free_key_range(mod_mem->base, mod_mem->size);
1231	if (mod_mem->size)
1232	module_memory_free(mod_mem->base, type);
1233	}
1234
1235	/* MOD_DATA hosts mod, so free it at last */
1236	lockdep_free_key_range(mod->mem[MOD_DATA].base, mod->mem[MOD_DATA].size);
1237	module_memory_free(mod->mem[MOD_DATA].base, MOD_DATA);
1238	}
1239
1240	/* Free a module, remove from lists, etc. */
1241	static void free_module(struct module *mod)
1242	{
1243	trace_module_free(mod);
1244
1245	mod_sysfs_teardown(mod);
1246
1247	/*
1248	* We leave it in list to prevent duplicate loads, but make sure
1249	* that noone uses it while it's being deconstructed.
1250	*/
1251	mutex_lock(&module_mutex);
1252	mod->state = MODULE_STATE_UNFORMED;
1253	mutex_unlock(&module_mutex);
1254
1255	/* Arch-specific cleanup. */
1256	module_arch_cleanup(mod);
1257
1258	/* Module unload stuff */
1259	module_unload_free(mod);
1260
1261	/* Free any allocated parameters. */
1262	destroy_params(mod->kp, mod->num_kp);
1263
1264	if (is_livepatch_module(mod))
1265	free_module_elf(mod);
1266
1267	/* Now we can delete it from the lists */
1268	mutex_lock(&module_mutex);
1269	/* Unlink carefully: kallsyms could be walking list. */
1270	list_del_rcu(&mod->list);
1271	mod_tree_remove(mod);
1272	/* Remove this module from bug list, this uses list_del_rcu */
1273	module_bug_cleanup(mod);
1274	/* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
1275	synchronize_rcu();
1276	if (try_add_tainted_module(mod))
1277	pr_err("%s: adding tainted module to the unloaded tainted modules list failed.\n",
1278	mod->name);
1279	mutex_unlock(&module_mutex);
1280
1281	/* This may be empty, but that's OK */
1282	module_arch_freeing_init(mod);
1283	kfree(mod->args);
1284	percpu_modfree(mod);
1285
1286	free_mod_mem(mod);
1287	}
1288
1289	void __symbol_get(const char symbol)
1290	{
1291	struct find_symbol_arg fsa = {
1292	.name = symbol,
1293	.gplok = true,
1294	.warn = true,
1295	};
1296
1297	preempt_disable();
1298	if (!find_symbol(&fsa))
1299	goto fail;
1300	if (fsa.license != GPL_ONLY) {
1301	pr_warn("failing symbol_get of non-GPLONLY symbol %s.\n",
1302	symbol);
1303	goto fail;
1304	}
1305	if (strong_try_module_get(fsa.owner))
1306	goto fail;
1307	preempt_enable();
1308	return (void *)kernel_symbol_value(fsa.sym);
1309	fail:
1310	preempt_enable();
1311	return NULL;
1312	}
1313	EXPORT_SYMBOL_GPL(__symbol_get);
1314
1315	/*
1316	* Ensure that an exported symbol [global namespace] does not already exist
1317	* in the kernel or in some other module's exported symbol table.
1318	*
1319	* You must hold the module_mutex.
1320	*/
1321	static int verify_exported_symbols(struct module *mod)
1322	{
1323	unsigned int i;
1324	const struct kernel_symbol *s;
1325	struct {
1326	const struct kernel_symbol *sym;
1327	unsigned int num;
1328	} arr[] = {
1329	{ mod->syms, mod->num_syms },
1330	{ mod->gpl_syms, mod->num_gpl_syms },
1331	};
1332
1333	for (i = 0; i < ARRAY_SIZE(arr); i++) {
1334	for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1335	struct find_symbol_arg fsa = {
1336	.name = kernel_symbol_name(s),
1337	.gplok = true,
1338	};
1339	if (find_symbol(&fsa)) {
1340	pr_err("%s: exports duplicate symbol %s"
1341	" (owned by %s)\n",
1342	mod->name, kernel_symbol_name(s),
1343	module_name(fsa.owner));
1344	return -ENOEXEC;
1345	}
1346	}
1347	}
1348	return 0;
1349	}
1350
1351	static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
1352	{
1353	/*
1354	* On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
1355	* before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
1356	* i386 has a similar problem but may not deserve a fix.
1357	*
1358	* If we ever have to ignore many symbols, consider refactoring the code to
1359	* only warn if referenced by a relocation.
1360	*/
1361	if (emachine == EM_386 \|\| emachine == EM_X86_64)
1362	return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
1363	return false;
1364	}
1365
1366	/* Change all symbols so that st_value encodes the pointer directly. */
1367	static int simplify_symbols(struct module mod, const struct load_info info)
1368	{
1369	Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1370	Elf_Sym sym = (void )symsec->sh_addr;
1371	unsigned long secbase;
1372	unsigned int i;
1373	int ret = 0;
1374	const struct kernel_symbol *ksym;
1375
1376	for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1377	const char *name = info->strtab + sym[i].st_name;
1378
1379	switch (sym[i].st_shndx) {
1380	case SHN_COMMON:
1381	/* Ignore common symbols */
1382	if (!strncmp(name, "__gnu_lto", 9))
1383	break;
1384
1385	/*
1386	* We compiled with -fno-common. These are not
1387	* supposed to happen.
1388	*/
1389	pr_debug("Common symbol: %s\n", name);
1390	pr_warn("%s: please compile with -fno-common\n",
1391	mod->name);
1392	ret = -ENOEXEC;
1393	break;
1394
1395	case SHN_ABS:
1396	/* Don't need to do anything */
1397	pr_debug("Absolute symbol: 0x%08lx %s\n",
1398	(long)sym[i].st_value, name);
1399	break;
1400
1401	case SHN_LIVEPATCH:
1402	/* Livepatch symbols are resolved by livepatch */
1403	break;
1404
1405	case SHN_UNDEF:
1406	ksym = resolve_symbol_wait(mod, info, name);
1407	/* Ok if resolved. */
1408	if (ksym && !IS_ERR(ksym)) {
1409	sym[i].st_value = kernel_symbol_value(ksym);
1410	break;
1411	}
1412
1413	/* Ok if weak or ignored. */
1414	if (!ksym &&
1415	(ELF_ST_BIND(sym[i].st_info) == STB_WEAK \|\|
1416	ignore_undef_symbol(info->hdr->e_machine, name)))
1417	break;
1418
1419	ret = PTR_ERR(ksym) ?: -ENOENT;
1420	pr_warn("%s: Unknown symbol %s (err %d)\n",
1421	mod->name, name, ret);
1422	break;
1423
1424	default:
1425	/* Divert to percpu allocation if a percpu var. */
1426	if (sym[i].st_shndx == info->index.pcpu)
1427	secbase = (unsigned long)mod_percpu(mod);
1428	else
1429	secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1430	sym[i].st_value += secbase;
1431	break;
1432	}
1433	}
1434
1435	return ret;
1436	}
1437
1438	static int apply_relocations(struct module mod, const struct load_info info)
1439	{
1440	unsigned int i;
1441	int err = 0;
1442
1443	/* Now do relocations. */
1444	for (i = 1; i < info->hdr->e_shnum; i++) {
1445	unsigned int infosec = info->sechdrs[i].sh_info;
1446
1447	/* Not a valid relocation section? */
1448	if (infosec >= info->hdr->e_shnum)
1449	continue;
1450
1451	/* Don't bother with non-allocated sections */
1452	if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
1453	continue;
1454
1455	if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
1456	err = klp_apply_section_relocs(mod, info->sechdrs,
1457	info->secstrings,
1458	info->strtab,
1459	info->index.sym, i,
1460	NULL);
1461	else if (info->sechdrs[i].sh_type == SHT_REL)
1462	err = apply_relocate(info->sechdrs, info->strtab,
1463	info->index.sym, i, mod);
1464	else if (info->sechdrs[i].sh_type == SHT_RELA)
1465	err = apply_relocate_add(info->sechdrs, info->strtab,
1466	info->index.sym, i, mod);
1467	if (err < 0)
1468	break;
1469	}
1470	return err;
1471	}
1472
1473	/* Additional bytes needed by arch in front of individual sections */
1474	unsigned int __weak arch_mod_section_prepend(struct module *mod,
1475	unsigned int section)
1476	{
1477	/* default implementation just returns zero */
1478	return 0;
1479	}
1480
1481	long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
1482	Elf_Shdr *sechdr, unsigned int section)
1483	{
1484	long offset;
1485	long mask = ((unsigned long)(type) & SH_ENTSIZE_TYPE_MASK) << SH_ENTSIZE_TYPE_SHIFT;
1486
1487	mod->mem[type].size += arch_mod_section_prepend(mod, section);
1488	offset = ALIGN(mod->mem[type].size, sechdr->sh_addralign ?: 1);
1489	mod->mem[type].size = offset + sechdr->sh_size;
1490
1491	WARN_ON_ONCE(offset & mask);
1492	return offset \| mask;
1493	}
1494
1495	bool module_init_layout_section(const char *sname)
1496	{
1497	#ifndef CONFIG_MODULE_UNLOAD
1498	if (module_exit_section(sname))
1499	return true;
1500	#endif
1501	return module_init_section(sname);
1502	}
1503
1504	static void __layout_sections(struct module mod, struct load_info info, bool is_init)
1505	{
1506	unsigned int m, i;
1507
1508	static const unsigned long masks[][2] = {
1509	/*
1510	* NOTE: all executable code must be the first section
1511	* in this array; otherwise modify the text_size
1512	* finder in the two loops below
1513	*/
1514	{ SHF_EXECINSTR \| SHF_ALLOC, ARCH_SHF_SMALL },
1515	{ SHF_ALLOC, SHF_WRITE \| ARCH_SHF_SMALL },
1516	{ SHF_RO_AFTER_INIT \| SHF_ALLOC, ARCH_SHF_SMALL },
1517	{ SHF_WRITE \| SHF_ALLOC, ARCH_SHF_SMALL },
1518	{ ARCH_SHF_SMALL \| SHF_ALLOC, 0 }
1519	};
1520	static const int core_m_to_mem_type[] = {
1521	MOD_TEXT,
1522	MOD_RODATA,
1523	MOD_RO_AFTER_INIT,
1524	MOD_DATA,
1525	MOD_DATA,
1526	};
1527	static const int init_m_to_mem_type[] = {
1528	MOD_INIT_TEXT,
1529	MOD_INIT_RODATA,
1530	MOD_INVALID,
1531	MOD_INIT_DATA,
1532	MOD_INIT_DATA,
1533	};
1534
1535	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1536	enum mod_mem_type type = is_init ? init_m_to_mem_type[m] : core_m_to_mem_type[m];
1537
1538	for (i = 0; i < info->hdr->e_shnum; ++i) {
1539	Elf_Shdr *s = &info->sechdrs[i];
1540	const char *sname = info->secstrings + s->sh_name;
1541
1542	if ((s->sh_flags & masks[m][0]) != masks[m][0]
1543	\|\| (s->sh_flags & masks[m][1])
1544	\|\| s->sh_entsize != ~0UL
1545	\|\| is_init != module_init_layout_section(sname))
1546	continue;
1547
1548	if (WARN_ON_ONCE(type == MOD_INVALID))
1549	continue;
1550
1551	s->sh_entsize = module_get_offset_and_type(mod, type, s, i);
1552	pr_debug("\t%s\n", sname);
1553	}
1554	}
1555	}
1556
1557	/*
1558	* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1559	* might -- code, read-only data, read-write data, small data. Tally
1560	* sizes, and place the offsets into sh_entsize fields: high bit means it
1561	* belongs in init.
1562	*/
1563	static void layout_sections(struct module mod, struct load_info info)
1564	{
1565	unsigned int i;
1566
1567	for (i = 0; i < info->hdr->e_shnum; i++)
1568	info->sechdrs[i].sh_entsize = ~0UL;
1569
1570	pr_debug("Core section allocation order for %s:\n", mod->name);
1571	__layout_sections(mod, info, false);
1572
1573	pr_debug("Init section allocation order for %s:\n", mod->name);
1574	__layout_sections(mod, info, true);
1575	}
1576
1577	static void module_license_taint_check(struct module mod, const char license)
1578	{
1579	if (!license)
1580	license = "unspecified";
1581
1582	if (!license_is_gpl_compatible(license)) {
1583	if (!test_taint(TAINT_PROPRIETARY_MODULE))
1584	pr_warn("%s: module license '%s' taints kernel.\n",
1585	mod->name, license);
1586	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
1587	LOCKDEP_NOW_UNRELIABLE);
1588	}
1589	}
1590
1591	static void setup_modinfo(struct module mod, struct load_info info)
1592	{
1593	struct module_attribute *attr;
1594	int i;
1595
1596	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1597	if (attr->setup)
1598	attr->setup(mod, get_modinfo(info, attr->attr.name));
1599	}
1600	}
1601
1602	static void free_modinfo(struct module *mod)
1603	{
1604	struct module_attribute *attr;
1605	int i;
1606
1607	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1608	if (attr->free)
1609	attr->free(mod);
1610	}
1611	}
1612
1613	void * __weak module_alloc(unsigned long size)
1614	{
1615	return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
1616	GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS,
1617	NUMA_NO_NODE, __builtin_return_address(0));
1618	}
1619
1620	bool __weak module_init_section(const char *name)
1621	{
1622	return strstarts(name, ".init");
1623	}
1624
1625	bool __weak module_exit_section(const char *name)
1626	{
1627	return strstarts(name, ".exit");
1628	}
1629
1630	static int validate_section_offset(struct load_info info, Elf_Shdr shdr)
1631	{
1632	#if defined(CONFIG_64BIT)
1633	unsigned long long secend;
1634	#else
1635	unsigned long secend;
1636	#endif
1637
1638	/*
1639	* Check for both overflow and offset/size being
1640	* too large.
1641	*/
1642	secend = shdr->sh_offset + shdr->sh_size;
1643	if (secend < shdr->sh_offset \|\| secend > info->len)
1644	return -ENOEXEC;
1645
1646	return 0;
1647	}
1648
1649	/*
1650	* Check userspace passed ELF module against our expectations, and cache
1651	* useful variables for further processing as we go.
1652	*
1653	* This does basic validity checks against section offsets and sizes, the
1654	* section name string table, and the indices used for it (sh_name).
1655	*
1656	* As a last step, since we're already checking the ELF sections we cache
1657	* useful variables which will be used later for our convenience:
1658	*
1659	* o pointers to section headers
1660	* o cache the modinfo symbol section
1661	* o cache the string symbol section
1662	* o cache the module section
1663	*
1664	* As a last step we set info->mod to the temporary copy of the module in
1665	* info->hdr. The final one will be allocated in move_module(). Any
1666	* modifications we make to our copy of the module will be carried over
1667	* to the final minted module.
1668	*/
1669	static int elf_validity_cache_copy(struct load_info *info, int flags)
1670	{
1671	unsigned int i;
1672	Elf_Shdr shdr, strhdr;
1673	int err;
1674	unsigned int num_mod_secs = 0, mod_idx;
1675	unsigned int num_info_secs = 0, info_idx;
1676	unsigned int num_sym_secs = 0, sym_idx;
1677
1678	if (info->len < sizeof(*(info->hdr))) {
1679	pr_err("Invalid ELF header len %lu\n", info->len);
1680	goto no_exec;
1681	}
1682
1683	if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0) {
1684	pr_err("Invalid ELF header magic: != %s\n", ELFMAG);
1685	goto no_exec;
1686	}
1687	if (info->hdr->e_type != ET_REL) {
1688	pr_err("Invalid ELF header type: %u != %u\n",
1689	info->hdr->e_type, ET_REL);
1690	goto no_exec;
1691	}
1692	if (!elf_check_arch(info->hdr)) {
1693	pr_err("Invalid architecture in ELF header: %u\n",
1694	info->hdr->e_machine);
1695	goto no_exec;
1696	}
1697	if (!module_elf_check_arch(info->hdr)) {
1698	pr_err("Invalid module architecture in ELF header: %u\n",
1699	info->hdr->e_machine);
1700	goto no_exec;
1701	}
1702	if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) {
1703	pr_err("Invalid ELF section header size\n");
1704	goto no_exec;
1705	}
1706
1707	/*
1708	* e_shnum is 16 bits, and sizeof(Elf_Shdr) is
1709	* known and small. So e_shnum * sizeof(Elf_Shdr)
1710	* will not overflow unsigned long on any platform.
1711	*/
1712	if (info->hdr->e_shoff >= info->len
1713	\|\| (info->hdr->e_shnum * sizeof(Elf_Shdr) >
1714	info->len - info->hdr->e_shoff)) {
1715	pr_err("Invalid ELF section header overflow\n");
1716	goto no_exec;
1717	}
1718
1719	info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
1720
1721	/*
1722	* Verify if the section name table index is valid.
1723	*/
1724	if (info->hdr->e_shstrndx == SHN_UNDEF
1725	\|\| info->hdr->e_shstrndx >= info->hdr->e_shnum) {
1726	pr_err("Invalid ELF section name index: %d \|\| e_shstrndx (%d) >= e_shnum (%d)\n",
1727	info->hdr->e_shstrndx, info->hdr->e_shstrndx,
1728	info->hdr->e_shnum);
1729	goto no_exec;
1730	}
1731
1732	strhdr = &info->sechdrs[info->hdr->e_shstrndx];
1733	err = validate_section_offset(info, strhdr);
1734	if (err < 0) {
1735	pr_err("Invalid ELF section hdr(type %u)\n", strhdr->sh_type);
1736	return err;
1737	}
1738
1739	/*
1740	* The section name table must be NUL-terminated, as required
1741	* by the spec. This makes strcmp and pr_* calls that access
1742	* strings in the section safe.
1743	*/
1744	info->secstrings = (void *)info->hdr + strhdr->sh_offset;
1745	if (strhdr->sh_size == 0) {
1746	pr_err("empty section name table\n");
1747	goto no_exec;
1748	}
1749	if (info->secstrings[strhdr->sh_size - 1] != '\0') {
1750	pr_err("ELF Spec violation: section name table isn't null terminated\n");
1751	goto no_exec;
1752	}
1753
1754	/*
1755	* The code assumes that section 0 has a length of zero and
1756	* an addr of zero, so check for it.
1757	*/
1758	if (info->sechdrs[0].sh_type != SHT_NULL
1759	\|\| info->sechdrs[0].sh_size != 0
1760	\|\| info->sechdrs[0].sh_addr != 0) {
1761	pr_err("ELF Spec violation: section 0 type(%d)!=SH_NULL or non-zero len or addr\n",
1762	info->sechdrs[0].sh_type);
1763	goto no_exec;
1764	}
1765
1766	for (i = 1; i < info->hdr->e_shnum; i++) {
1767	shdr = &info->sechdrs[i];
1768	switch (shdr->sh_type) {
1769	case SHT_NULL:
1770	case SHT_NOBITS:
1771	continue;
1772	case SHT_SYMTAB:
1773	if (shdr->sh_link == SHN_UNDEF
1774	\|\| shdr->sh_link >= info->hdr->e_shnum) {
1775	pr_err("Invalid ELF sh_link!=SHN_UNDEF(%d) or (sh_link(%d) >= hdr->e_shnum(%d)\n",
1776	shdr->sh_link, shdr->sh_link,
1777	info->hdr->e_shnum);
1778	goto no_exec;
1779	}
1780	num_sym_secs++;
1781	sym_idx = i;
1782	fallthrough;
1783	default:
1784	err = validate_section_offset(info, shdr);
1785	if (err < 0) {
1786	pr_err("Invalid ELF section in module (section %u type %u)\n",
1787	i, shdr->sh_type);
1788	return err;
1789	}
1790	if (strcmp(info->secstrings + shdr->sh_name,
1791	".gnu.linkonce.this_module") == 0) {
1792	num_mod_secs++;
1793	mod_idx = i;
1794	} else if (strcmp(info->secstrings + shdr->sh_name,
1795	".modinfo") == 0) {
1796	num_info_secs++;
1797	info_idx = i;
1798	}
1799
1800	if (shdr->sh_flags & SHF_ALLOC) {
1801	if (shdr->sh_name >= strhdr->sh_size) {
1802	pr_err("Invalid ELF section name in module (section %u type %u)\n",
1803	i, shdr->sh_type);
1804	return -ENOEXEC;
1805	}
1806	}
1807	break;
1808	}
1809	}
1810
1811	if (num_info_secs > 1) {
1812	pr_err("Only one .modinfo section must exist.\n");
1813	goto no_exec;
1814	} else if (num_info_secs == 1) {
1815	/* Try to find a name early so we can log errors with a module name */
1816	info->index.info = info_idx;
1817	info->name = get_modinfo(info, "name");
1818	}
1819
1820	if (num_sym_secs != 1) {
1821	pr_warn("%s: module has no symbols (stripped?)\n",
1822	info->name ?: "(missing .modinfo section or name field)");
1823	goto no_exec;
1824	}
1825
1826	/* Sets internal symbols and strings. */
1827	info->index.sym = sym_idx;
1828	shdr = &info->sechdrs[sym_idx];
1829	info->index.str = shdr->sh_link;
1830	info->strtab = (char *)info->hdr + info->sechdrs[info->index.str].sh_offset;
1831
1832	/*
1833	* The ".gnu.linkonce.this_module" ELF section is special. It is
1834	* what modpost uses to refer to __this_module and let's use rely
1835	* on THIS_MODULE to point to &__this_module properly. The kernel's
1836	* modpost declares it on each modules's *.mod.c file. If the struct
1837	* module of the kernel changes a full kernel rebuild is required.
1838	*
1839	* We have a few expectaions for this special section, the following
1840	* code validates all this for us:
1841	*
1842	* o Only one section must exist
1843	* o We expect the kernel to always have to allocate it: SHF_ALLOC
1844	* o The section size must match the kernel's run time's struct module
1845	* size
1846	*/
1847	if (num_mod_secs != 1) {
1848	pr_err("module %s: Only one .gnu.linkonce.this_module section must exist.\n",
1849	info->name ?: "(missing .modinfo section or name field)");
1850	goto no_exec;
1851	}
1852
1853	shdr = &info->sechdrs[mod_idx];
1854
1855	/*
1856	* This is already implied on the switch above, however let's be
1857	* pedantic about it.
1858	*/
1859	if (shdr->sh_type == SHT_NOBITS) {
1860	pr_err("module %s: .gnu.linkonce.this_module section must have a size set\n",
1861	info->name ?: "(missing .modinfo section or name field)");
1862	goto no_exec;
1863	}
1864
1865	if (!(shdr->sh_flags & SHF_ALLOC)) {
1866	pr_err("module %s: .gnu.linkonce.this_module must occupy memory during process execution\n",
1867	info->name ?: "(missing .modinfo section or name field)");
1868	goto no_exec;
1869	}
1870
1871	if (shdr->sh_size != sizeof(struct module)) {
1872	pr_err("module %s: .gnu.linkonce.this_module section size must match the kernel's built struct module size at run time\n",
1873	info->name ?: "(missing .modinfo section or name field)");
1874	goto no_exec;
1875	}
1876
1877	info->index.mod = mod_idx;
1878
1879	/* This is temporary: point mod into copy of data. */
1880	info->mod = (void *)info->hdr + shdr->sh_offset;
1881
1882	/*
1883	* If we didn't load the .modinfo 'name' field earlier, fall back to
1884	* on-disk struct mod 'name' field.
1885	*/
1886	if (!info->name)
1887	info->name = info->mod->name;
1888
1889	if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
1890	info->index.vers = 0; /* Pretend no __versions section! */
1891	else
1892	info->index.vers = find_sec(info, "__versions");
1893
1894	info->index.pcpu = find_pcpusec(info);
1895
1896	return 0;
1897
1898	no_exec:
1899	return -ENOEXEC;
1900	}
1901
1902	#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
1903
1904	static int copy_chunked_from_user(void dst, const void __user usrc, unsigned long len)
1905	{
1906	do {
1907	unsigned long n = min(len, COPY_CHUNK_SIZE);
1908
1909	if (copy_from_user(dst, usrc, n) != 0)
1910	return -EFAULT;
1911	cond_resched();
1912	dst += n;
1913	usrc += n;
1914	len -= n;
1915	} while (len);
1916	return 0;
1917	}
1918
1919	static int check_modinfo_livepatch(struct module mod, struct load_info info)
1920	{
1921	if (!get_modinfo(info, "livepatch"))
1922	/* Nothing more to do */
1923	return 0;
1924
1925	if (set_livepatch_module(mod))
1926	return 0;
1927
1928	pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
1929	mod->name);
1930	return -ENOEXEC;
1931	}
1932
1933	static void check_modinfo_retpoline(struct module mod, struct load_info info)
1934	{
1935	if (retpoline_module_ok(get_modinfo(info, "retpoline")))
1936	return;
1937
1938	pr_warn("%s: loading module not compiled with retpoline compiler.\n",
1939	mod->name);
1940	}
1941
1942	/* Sets info->hdr and info->len. */
1943	static int copy_module_from_user(const void __user *umod, unsigned long len,
1944	struct load_info *info)
1945	{
1946	int err;
1947
1948	info->len = len;
1949	if (info->len < sizeof(*(info->hdr)))
1950	return -ENOEXEC;
1951
1952	err = security_kernel_load_data(LOADING_MODULE, true);
1953	if (err)
1954	return err;
1955
1956	/* Suck in entire file: we'll want most of it. */
1957	info->hdr = __vmalloc(info->len, GFP_KERNEL \| __GFP_NOWARN);
1958	if (!info->hdr)
1959	return -ENOMEM;
1960
1961	if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
1962	err = -EFAULT;
1963	goto out;
1964	}
1965
1966	err = security_kernel_post_load_data((char *)info->hdr, info->len,
1967	LOADING_MODULE, "init_module");
1968	out:
1969	if (err)
1970	vfree(info->hdr);
1971
1972	return err;
1973	}
1974
1975	static void free_copy(struct load_info *info, int flags)
1976	{
1977	if (flags & MODULE_INIT_COMPRESSED_FILE)
1978	module_decompress_cleanup(info);
1979	else
1980	vfree(info->hdr);
1981	}
1982
1983	static int rewrite_section_headers(struct load_info *info, int flags)
1984	{
1985	unsigned int i;
1986
1987	/* This should always be true, but let's be sure. */
1988	info->sechdrs[0].sh_addr = 0;
1989
1990	for (i = 1; i < info->hdr->e_shnum; i++) {
1991	Elf_Shdr *shdr = &info->sechdrs[i];
1992
1993	/*
1994	* Mark all sections sh_addr with their address in the
1995	* temporary image.
1996	*/
1997	shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
1998
1999	}
2000
2001	/* Track but don't keep modinfo and version sections. */
2002	info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2003	info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2004
2005	return 0;
2006	}
2007
2008	/*
2009	* These calls taint the kernel depending certain module circumstances */
2010	static void module_augment_kernel_taints(struct module mod, struct load_info info)
2011	{
2012	int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
2013
2014	if (!get_modinfo(info, "intree")) {
2015	if (!test_taint(TAINT_OOT_MODULE))
2016	pr_warn("%s: loading out-of-tree module taints kernel.\n",
2017	mod->name);
2018	add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
2019	}
2020
2021	check_modinfo_retpoline(mod, info);
2022
2023	if (get_modinfo(info, "staging")) {
2024	add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
2025	pr_warn("%s: module is from the staging directory, the quality "
2026	"is unknown, you have been warned.\n", mod->name);
2027	}
2028
2029	if (is_livepatch_module(mod)) {
2030	add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK);
2031	pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2032	mod->name);
2033	}
2034
2035	module_license_taint_check(mod, get_modinfo(info, "license"));
2036
2037	if (get_modinfo(info, "test")) {
2038	if (!test_taint(TAINT_TEST))
2039	pr_warn("%s: loading test module taints kernel.\n",
2040	mod->name);
2041	add_taint_module(mod, TAINT_TEST, LOCKDEP_STILL_OK);
2042	}
2043	#ifdef CONFIG_MODULE_SIG
2044	mod->sig_ok = info->sig_ok;
2045	if (!mod->sig_ok) {
2046	pr_notice_once("%s: module verification failed: signature "
2047	"and/or required key missing - tainting "
2048	"kernel\n", mod->name);
2049	add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
2050	}
2051	#endif
2052
2053	/*
2054	* ndiswrapper is under GPL by itself, but loads proprietary modules.
2055	* Don't use add_taint_module(), as it would prevent ndiswrapper from
2056	* using GPL-only symbols it needs.
2057	*/
2058	if (strcmp(mod->name, "ndiswrapper") == 0)
2059	add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2060
2061	/* driverloader was caught wrongly pretending to be under GPL */
2062	if (strcmp(mod->name, "driverloader") == 0)
2063	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2064	LOCKDEP_NOW_UNRELIABLE);
2065
2066	/* lve claims to be GPL but upstream won't provide source */
2067	if (strcmp(mod->name, "lve") == 0)
2068	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2069	LOCKDEP_NOW_UNRELIABLE);
2070
2071	if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
2072	pr_warn("%s: module license taints kernel.\n", mod->name);
2073
2074	}
2075
2076	static int check_modinfo(struct module mod, struct load_info info, int flags)
2077	{
2078	const char *modmagic = get_modinfo(info, "vermagic");
2079	int err;
2080
2081	if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2082	modmagic = NULL;
2083
2084	/* This is allowed: modprobe --force will invalidate it. */
2085	if (!modmagic) {
2086	err = try_to_force_load(mod, "bad vermagic");
2087	if (err)
2088	return err;
2089	} else if (!same_magic(modmagic, vermagic, info->index.vers)) {
2090	pr_err("%s: version magic '%s' should be '%s'\n",
2091	info->name, modmagic, vermagic);
2092	return -ENOEXEC;
2093	}
2094
2095	err = check_modinfo_livepatch(mod, info);
2096	if (err)
2097	return err;
2098
2099	return 0;
2100	}
2101
2102	static int find_module_sections(struct module mod, struct load_info info)
2103	{
2104	mod->kp = section_objs(info, "__param",
2105	sizeof(*mod->kp), &mod->num_kp);
2106	mod->syms = section_objs(info, "__ksymtab",
2107	sizeof(*mod->syms), &mod->num_syms);
2108	mod->crcs = section_addr(info, "__kcrctab");
2109	mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
2110	sizeof(*mod->gpl_syms),
2111	&mod->num_gpl_syms);
2112	mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
2113
2114	#ifdef CONFIG_CONSTRUCTORS
2115	mod->ctors = section_objs(info, ".ctors",
2116	sizeof(*mod->ctors), &mod->num_ctors);
2117	if (!mod->ctors)
2118	mod->ctors = section_objs(info, ".init_array",
2119	sizeof(*mod->ctors), &mod->num_ctors);
2120	else if (find_sec(info, ".init_array")) {
2121	/*
2122	* This shouldn't happen with same compiler and binutils
2123	* building all parts of the module.
2124	*/
2125	pr_warn("%s: has both .ctors and .init_array.\n",
2126	mod->name);
2127	return -EINVAL;
2128	}
2129	#endif
2130
2131	mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1,
2132	&mod->noinstr_text_size);
2133
2134	#ifdef CONFIG_TRACEPOINTS
2135	mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
2136	sizeof(*mod->tracepoints_ptrs),
2137	&mod->num_tracepoints);
2138	#endif
2139	#ifdef CONFIG_TREE_SRCU
2140	mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs",
2141	sizeof(*mod->srcu_struct_ptrs),
2142	&mod->num_srcu_structs);
2143	#endif
2144	#ifdef CONFIG_BPF_EVENTS
2145	mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map",
2146	sizeof(*mod->bpf_raw_events),
2147	&mod->num_bpf_raw_events);
2148	#endif
2149	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
2150	mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size);
2151	#endif
2152	#ifdef CONFIG_JUMP_LABEL
2153	mod->jump_entries = section_objs(info, "__jump_table",
2154	sizeof(*mod->jump_entries),
2155	&mod->num_jump_entries);
2156	#endif
2157	#ifdef CONFIG_EVENT_TRACING
2158	mod->trace_events = section_objs(info, "_ftrace_events",
2159	sizeof(*mod->trace_events),
2160	&mod->num_trace_events);
2161	mod->trace_evals = section_objs(info, "_ftrace_eval_map",
2162	sizeof(*mod->trace_evals),
2163	&mod->num_trace_evals);
2164	#endif
2165	#ifdef CONFIG_TRACING
2166	mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
2167	sizeof(*mod->trace_bprintk_fmt_start),
2168	&mod->num_trace_bprintk_fmt);
2169	#endif
2170	#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2171	/* sechdrs[0].sh_size is always zero */
2172	mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION,
2173	sizeof(*mod->ftrace_callsites),
2174	&mod->num_ftrace_callsites);
2175	#endif
2176	#ifdef CONFIG_FUNCTION_ERROR_INJECTION
2177	mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
2178	sizeof(*mod->ei_funcs),
2179	&mod->num_ei_funcs);
2180	#endif
2181	#ifdef CONFIG_KPROBES
2182	mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1,
2183	&mod->kprobes_text_size);
2184	mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist",
2185	sizeof(unsigned long),
2186	&mod->num_kprobe_blacklist);
2187	#endif
2188	#ifdef CONFIG_PRINTK_INDEX
2189	mod->printk_index_start = section_objs(info, ".printk_index",
2190	sizeof(*mod->printk_index_start),
2191	&mod->printk_index_size);
2192	#endif
2193	#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
2194	mod->static_call_sites = section_objs(info, ".static_call_sites",
2195	sizeof(*mod->static_call_sites),
2196	&mod->num_static_call_sites);
2197	#endif
2198	#if IS_ENABLED(CONFIG_KUNIT)
2199	mod->kunit_suites = section_objs(info, ".kunit_test_suites",
2200	sizeof(*mod->kunit_suites),
2201	&mod->num_kunit_suites);
2202	#endif
2203
2204	mod->extable = section_objs(info, "__ex_table",
2205	sizeof(*mod->extable), &mod->num_exentries);
2206
2207	if (section_addr(info, "__obsparm"))
2208	pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2209
2210	#ifdef CONFIG_DYNAMIC_DEBUG_CORE
2211	mod->dyndbg_info.descs = section_objs(info, "__dyndbg",
2212	sizeof(*mod->dyndbg_info.descs),
2213	&mod->dyndbg_info.num_descs);
2214	mod->dyndbg_info.classes = section_objs(info, "__dyndbg_classes",
2215	sizeof(*mod->dyndbg_info.classes),
2216	&mod->dyndbg_info.num_classes);
2217	#endif
2218
2219	return 0;
2220	}
2221
2222	static int move_module(struct module mod, struct load_info info)
2223	{
2224	int i;
2225	void *ptr;
2226	enum mod_mem_type t = 0;
2227	int ret = -ENOMEM;
2228
2229	for_each_mod_mem_type(type) {
2230	if (!mod->mem[type].size) {
2231	mod->mem[type].base = NULL;
2232	continue;
2233	}
2234	mod->mem[type].size = PAGE_ALIGN(mod->mem[type].size);
2235	ptr = module_memory_alloc(mod->mem[type].size, type);
2236	/*
2237	* The pointer to these blocks of memory are stored on the module
2238	* structure and we keep that around so long as the module is
2239	* around. We only free that memory when we unload the module.
2240	* Just mark them as not being a leak then. The .init* ELF
2241	* sections do get freed after boot so we could treat them
2242	* slightly differently with kmemleak_ignore() and only grey
2243	* them out as they work as typical memory allocations which
2244	* do eventually get freed, but let's just keep things simple
2245	* and avoid any false positives.
2246	*/
2247	kmemleak_not_leak(ptr);
2248	if (!ptr) {
2249	t = type;
2250	goto out_enomem;
2251	}
2252	memset(ptr, 0, mod->mem[type].size);
2253	mod->mem[type].base = ptr;
2254	}
2255
2256	/* Transfer each section which specifies SHF_ALLOC */
2257	pr_debug("Final section addresses for %s:\n", mod->name);
2258	for (i = 0; i < info->hdr->e_shnum; i++) {
2259	void *dest;
2260	Elf_Shdr *shdr = &info->sechdrs[i];
2261	enum mod_mem_type type = shdr->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
2262
2263	if (!(shdr->sh_flags & SHF_ALLOC))
2264	continue;
2265
2266	dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK);
2267
2268	if (shdr->sh_type != SHT_NOBITS) {
2269	/*
2270	* Our ELF checker already validated this, but let's
2271	* be pedantic and make the goal clearer. We actually
2272	* end up copying over all modifications made to the
2273	* userspace copy of the entire struct module.
2274	*/
2275	if (i == info->index.mod &&
2276	(WARN_ON_ONCE(shdr->sh_size != sizeof(struct module)))) {
2277	ret = -ENOEXEC;
2278	goto out_enomem;
2279	}
2280	memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2281	}
2282	/*
2283	* Update the userspace copy's ELF section address to point to
2284	* our newly allocated memory as a pure convenience so that
2285	* users of info can keep taking advantage and using the newly
2286	* minted official memory area.
2287	*/
2288	shdr->sh_addr = (unsigned long)dest;
2289	pr_debug("\t0x%lx 0x%.8lx %s\n", (long)shdr->sh_addr,
2290	(long)shdr->sh_size, info->secstrings + shdr->sh_name);
2291	}
2292
2293	return 0;
2294	out_enomem:
2295	for (t--; t >= 0; t--)
2296	module_memory_free(mod->mem[t].base, t);
2297	return ret;
2298	}
2299
2300	static int check_export_symbol_versions(struct module *mod)
2301	{
2302	#ifdef CONFIG_MODVERSIONS
2303	if ((mod->num_syms && !mod->crcs) \|\|
2304	(mod->num_gpl_syms && !mod->gpl_crcs)) {
2305	return try_to_force_load(mod,
2306	"no versions for exported symbols");
2307	}
2308	#endif
2309	return 0;
2310	}
2311
2312	static void flush_module_icache(const struct module *mod)
2313	{
2314	/*
2315	* Flush the instruction cache, since we've played with text.
2316	* Do it before processing of module parameters, so the module
2317	* can provide parameter accessor functions of its own.
2318	*/
2319	for_each_mod_mem_type(type) {
2320	const struct module_memory *mod_mem = &mod->mem[type];
2321
2322	if (mod_mem->size) {
2323	flush_icache_range((unsigned long)mod_mem->base,
2324	(unsigned long)mod_mem->base + mod_mem->size);
2325	}
2326	}
2327	}
2328
2329	bool __weak module_elf_check_arch(Elf_Ehdr *hdr)
2330	{
2331	return true;
2332	}
2333
2334	int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2335	Elf_Shdr *sechdrs,
2336	char *secstrings,
2337	struct module *mod)
2338	{
2339	return 0;
2340	}
2341
2342	/* module_blacklist is a comma-separated list of module names */
2343	static char *module_blacklist;
2344	static bool blacklisted(const char *module_name)
2345	{
2346	const char *p;
2347	size_t len;
2348
2349	if (!module_blacklist)
2350	return false;
2351
2352	for (p = module_blacklist; *p; p += len) {
2353	len = strcspn(p, ",");
2354	if (strlen(module_name) == len && !memcmp(module_name, p, len))
2355	return true;
2356	if (p[len] == ',')
2357	len++;
2358	}
2359	return false;
2360	}
2361	core_param(module_blacklist, module_blacklist, charp, 0400);
2362
2363	static struct module layout_and_allocate(struct load_info info, int flags)
2364	{
2365	struct module *mod;
2366	unsigned int ndx;
2367	int err;
2368
2369	/* Allow arches to frob section contents and sizes. */
2370	err = module_frob_arch_sections(info->hdr, info->sechdrs,
2371	info->secstrings, info->mod);
2372	if (err < 0)
2373	return ERR_PTR(err);
2374
2375	err = module_enforce_rwx_sections(info->hdr, info->sechdrs,
2376	info->secstrings, info->mod);
2377	if (err < 0)
2378	return ERR_PTR(err);
2379
2380	/* We will do a special allocation for per-cpu sections later. */
2381	info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2382
2383	/*
2384	* Mark ro_after_init section with SHF_RO_AFTER_INIT so that
2385	* layout_sections() can put it in the right place.
2386	* Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
2387	*/
2388	ndx = find_sec(info, ".data..ro_after_init");
2389	if (ndx)
2390	info->sechdrs[ndx].sh_flags \|= SHF_RO_AFTER_INIT;
2391	/*
2392	* Mark the __jump_table section as ro_after_init as well: these data
2393	* structures are never modified, with the exception of entries that
2394	* refer to code in the __init section, which are annotated as such
2395	* at module load time.
2396	*/
2397	ndx = find_sec(info, "__jump_table");
2398	if (ndx)
2399	info->sechdrs[ndx].sh_flags \|= SHF_RO_AFTER_INIT;
2400
2401	/*
2402	* Determine total sizes, and put offsets in sh_entsize. For now
2403	* this is done generically; there doesn't appear to be any
2404	* special cases for the architectures.
2405	*/
2406	layout_sections(info->mod, info);
2407	layout_symtab(info->mod, info);
2408
2409	/* Allocate and move to the final place */
2410	err = move_module(info->mod, info);
2411	if (err)
2412	return ERR_PTR(err);
2413
2414	/* Module has been copied to its final place now: return it. */
2415	mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2416	kmemleak_load_module(mod, info);
2417	return mod;
2418	}
2419
2420	/* mod is no longer valid after this! */
2421	static void module_deallocate(struct module mod, struct load_info info)
2422	{
2423	percpu_modfree(mod);
2424	module_arch_freeing_init(mod);
2425
2426	free_mod_mem(mod);
2427	}
2428
2429	int __weak module_finalize(const Elf_Ehdr *hdr,
2430	const Elf_Shdr *sechdrs,
2431	struct module *me)
2432	{
2433	return 0;
2434	}
2435
2436	static int post_relocation(struct module mod, const struct load_info info)
2437	{
2438	/* Sort exception table now relocations are done. */
2439	sort_extable(mod->extable, mod->extable + mod->num_exentries);
2440
2441	/* Copy relocated percpu area over. */
2442	percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
2443	info->sechdrs[info->index.pcpu].sh_size);
2444
2445	/* Setup kallsyms-specific fields. */
2446	add_kallsyms(mod, info);
2447
2448	/* Arch-specific module finalizing. */
2449	return module_finalize(info->hdr, info->sechdrs, mod);
2450	}
2451
2452	/* Call module constructors. */
2453	static void do_mod_ctors(struct module *mod)
2454	{
2455	#ifdef CONFIG_CONSTRUCTORS
2456	unsigned long i;
2457
2458	for (i = 0; i < mod->num_ctors; i++)
2459	mod->ctors[i]();
2460	#endif
2461	}
2462
2463	/* For freeing module_init on success, in case kallsyms traversing */
2464	struct mod_initfree {
2465	struct llist_node node;
2466	void *init_text;
2467	void *init_data;
2468	void *init_rodata;
2469	};
2470
2471	static void do_free_init(struct work_struct *w)
2472	{
2473	struct llist_node pos, n, *list;
2474	struct mod_initfree *initfree;
2475
2476	list = llist_del_all(&init_free_list);
2477
2478	synchronize_rcu();
2479
2480	llist_for_each_safe(pos, n, list) {
2481	initfree = container_of(pos, struct mod_initfree, node);
2482	module_memfree(initfree->init_text);
2483	module_memfree(initfree->init_data);
2484	module_memfree(initfree->init_rodata);
2485	kfree(initfree);
2486	}
2487	}
2488
2489	#undef MODULE_PARAM_PREFIX
2490	#define MODULE_PARAM_PREFIX "module."
2491	/* Default value for module->async_probe_requested */
2492	static bool async_probe;
2493	module_param(async_probe, bool, 0644);
2494
2495	/*
2496	* This is where the real work happens.
2497	*
2498	* Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
2499	* helper command 'lx-symbols'.
2500	*/
2501	static noinline int do_init_module(struct module *mod)
2502	{
2503	int ret = 0;
2504	struct mod_initfree *freeinit;
2505	#if defined(CONFIG_MODULE_STATS)
2506	unsigned int text_size = 0, total_size = 0;
2507
2508	for_each_mod_mem_type(type) {
2509	const struct module_memory *mod_mem = &mod->mem[type];
2510	if (mod_mem->size) {
2511	total_size += mod_mem->size;
2512	if (type == MOD_TEXT \|\| type == MOD_INIT_TEXT)
2513	text_size += mod_mem->size;
2514	}
2515	}
2516	#endif
2517
2518	freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
2519	if (!freeinit) {
2520	ret = -ENOMEM;
2521	goto fail;
2522	}
2523	freeinit->init_text = mod->mem[MOD_INIT_TEXT].base;
2524	freeinit->init_data = mod->mem[MOD_INIT_DATA].base;
2525	freeinit->init_rodata = mod->mem[MOD_INIT_RODATA].base;
2526
2527	do_mod_ctors(mod);
2528	/* Start the module */
2529	if (mod->init != NULL)
2530	ret = do_one_initcall(mod->init);
2531	if (ret < 0) {
2532	goto fail_free_freeinit;
2533	}
2534	if (ret > 0) {
2535	pr_warn("%s: '%s'->init suspiciously returned %d, it should "
2536	"follow 0/-E convention\n"
2537	"%s: loading module anyway...\n",
2538	__func__, mod->name, ret, __func__);
2539	dump_stack();
2540	}
2541
2542	/* Now it's a first class citizen! */
2543	mod->state = MODULE_STATE_LIVE;
2544	blocking_notifier_call_chain(&module_notify_list,
2545	MODULE_STATE_LIVE, mod);
2546
2547	/* Delay uevent until module has finished its init routine */
2548	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
2549
2550	/*
2551	* We need to finish all async code before the module init sequence
2552	* is done. This has potential to deadlock if synchronous module
2553	* loading is requested from async (which is not allowed!).
2554	*
2555	* See commit 0fdff3ec6d87 ("async, kmod: warn on synchronous
2556	* request_module() from async workers") for more details.
2557	*/
2558	if (!mod->async_probe_requested)
2559	async_synchronize_full();
2560
2561	ftrace_free_mem(mod, mod->mem[MOD_INIT_TEXT].base,
2562	mod->mem[MOD_INIT_TEXT].base + mod->mem[MOD_INIT_TEXT].size);
2563	mutex_lock(&module_mutex);
2564	/* Drop initial reference. */
2565	module_put(mod);
2566	trim_init_extable(mod);
2567	#ifdef CONFIG_KALLSYMS
2568	/* Switch to core kallsyms now init is done: kallsyms may be walking! */
2569	rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
2570	#endif
2571	module_enable_ro(mod, true);
2572	mod_tree_remove_init(mod);
2573	module_arch_freeing_init(mod);
2574	for_class_mod_mem_type(type, init) {
2575	mod->mem[type].base = NULL;
2576	mod->mem[type].size = 0;
2577	}
2578
2579	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
2580	/* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */
2581	mod->btf_data = NULL;
2582	#endif
2583	/*
2584	* We want to free module_init, but be aware that kallsyms may be
2585	* walking this with preempt disabled. In all the failure paths, we
2586	* call synchronize_rcu(), but we don't want to slow down the success
2587	* path. module_memfree() cannot be called in an interrupt, so do the
2588	* work and call synchronize_rcu() in a work queue.
2589	*
2590	* Note that module_alloc() on most architectures creates W+X page
2591	* mappings which won't be cleaned up until do_free_init() runs. Any
2592	* code such as mark_rodata_ro() which depends on those mappings to
2593	* be cleaned up needs to sync with the queued work - ie
2594	* rcu_barrier()
2595	*/
2596	if (llist_add(&freeinit->node, &init_free_list))
2597	schedule_work(&init_free_wq);
2598
2599	mutex_unlock(&module_mutex);
2600	wake_up_all(&module_wq);
2601
2602	mod_stat_add_long(text_size, &total_text_size);
2603	mod_stat_add_long(total_size, &total_mod_size);
2604
2605	mod_stat_inc(&modcount);
2606
2607	return 0;
2608
2609	fail_free_freeinit:
2610	kfree(freeinit);
2611	fail:
2612	/* Try to protect us from buggy refcounters. */
2613	mod->state = MODULE_STATE_GOING;
2614	synchronize_rcu();
2615	module_put(mod);
2616	blocking_notifier_call_chain(&module_notify_list,
2617	MODULE_STATE_GOING, mod);
2618	klp_module_going(mod);
2619	ftrace_release_mod(mod);
2620	free_module(mod);
2621	wake_up_all(&module_wq);
2622
2623	return ret;
2624	}
2625
2626	static int may_init_module(void)
2627	{
2628	if (!capable(CAP_SYS_MODULE) \|\| modules_disabled)
2629	return -EPERM;
2630
2631	return 0;
2632	}
2633
2634	/* Is this module of this name done loading? No locks held. */
2635	static bool finished_loading(const char *name)
2636	{
2637	struct module *mod;
2638	bool ret;
2639
2640	/*
2641	* The module_mutex should not be a heavily contended lock;
2642	* if we get the occasional sleep here, we'll go an extra iteration
2643	* in the wait_event_interruptible(), which is harmless.
2644	*/
2645	sched_annotate_sleep();
2646	mutex_lock(&module_mutex);
2647	mod = find_module_all(name, strlen(name), true);
2648	ret = !mod \|\| mod->state == MODULE_STATE_LIVE
2649	\|\| mod->state == MODULE_STATE_GOING;
2650	mutex_unlock(&module_mutex);
2651
2652	return ret;
2653	}
2654
2655	/* Must be called with module_mutex held */
2656	static int module_patient_check_exists(const char *name,
2657	enum fail_dup_mod_reason reason)
2658	{
2659	struct module *old;
2660	int err = 0;
2661
2662	old = find_module_all(name, strlen(name), true);
2663	if (old == NULL)
2664	return 0;
2665
2666	if (old->state == MODULE_STATE_COMING \|\|
2667	old->state == MODULE_STATE_UNFORMED) {
2668	/* Wait in case it fails to load. */
2669	mutex_unlock(&module_mutex);
2670	err = wait_event_interruptible(module_wq,
2671	finished_loading(name));
2672	mutex_lock(&module_mutex);
2673	if (err)
2674	return err;
2675
2676	/* The module might have gone in the meantime. */
2677	old = find_module_all(name, strlen(name), true);
2678	}
2679
2680	if (try_add_failed_module(name, reason))
2681	pr_warn("Could not add fail-tracking for module: %s\n", name);
2682
2683	/*
2684	* We are here only when the same module was being loaded. Do
2685	* not try to load it again right now. It prevents long delays
2686	* caused by serialized module load failures. It might happen
2687	* when more devices of the same type trigger load of
2688	* a particular module.
2689	*/
2690	if (old && old->state == MODULE_STATE_LIVE)
2691	return -EEXIST;
2692	return -EBUSY;
2693	}
2694
2695	/*
2696	* We try to place it in the list now to make sure it's unique before
2697	* we dedicate too many resources. In particular, temporary percpu
2698	* memory exhaustion.
2699	*/
2700	static int add_unformed_module(struct module *mod)
2701	{
2702	int err;
2703
2704	mod->state = MODULE_STATE_UNFORMED;
2705
2706	mutex_lock(&module_mutex);
2707	err = module_patient_check_exists(mod->name, FAIL_DUP_MOD_LOAD);
2708	if (err)
2709	goto out;
2710
2711	mod_update_bounds(mod);
2712	list_add_rcu(&mod->list, &modules);
2713	mod_tree_insert(mod);
2714	err = 0;
2715
2716	out:
2717	mutex_unlock(&module_mutex);
2718	return err;
2719	}
2720
2721	static int complete_formation(struct module mod, struct load_info info)
2722	{
2723	int err;
2724
2725	mutex_lock(&module_mutex);
2726
2727	/* Find duplicate symbols (must be called under lock). */
2728	err = verify_exported_symbols(mod);
2729	if (err < 0)
2730	goto out;
2731
2732	/* These rely on module_mutex for list integrity. */
2733	module_bug_finalize(info->hdr, info->sechdrs, mod);
2734	module_cfi_finalize(info->hdr, info->sechdrs, mod);
2735
2736	module_enable_ro(mod, false);
2737	module_enable_nx(mod);
2738	module_enable_x(mod);
2739
2740	/*
2741	* Mark state as coming so strong_try_module_get() ignores us,
2742	* but kallsyms etc. can see us.
2743	*/
2744	mod->state = MODULE_STATE_COMING;
2745	mutex_unlock(&module_mutex);
2746
2747	return 0;
2748
2749	out:
2750	mutex_unlock(&module_mutex);
2751	return err;
2752	}
2753
2754	static int prepare_coming_module(struct module *mod)
2755	{
2756	int err;
2757
2758	ftrace_module_enable(mod);
2759	err = klp_module_coming(mod);
2760	if (err)
2761	return err;
2762
2763	err = blocking_notifier_call_chain_robust(&module_notify_list,
2764	MODULE_STATE_COMING, MODULE_STATE_GOING, mod);
2765	err = notifier_to_errno(err);
2766	if (err)
2767	klp_module_going(mod);
2768
2769	return err;
2770	}
2771
2772	static int unknown_module_param_cb(char param, char val, const char *modname,
2773	void *arg)
2774	{
2775	struct module *mod = arg;
2776	int ret;
2777
2778	if (strcmp(param, "async_probe") == 0) {
2779	if (kstrtobool(val, &mod->async_probe_requested))
2780	mod->async_probe_requested = true;
2781	return 0;
2782	}
2783
2784	/* Check for magic 'dyndbg' arg */
2785	ret = ddebug_dyndbg_module_param_cb(param, val, modname);
2786	if (ret != 0)
2787	pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
2788	return 0;
2789	}
2790
2791	/* Module within temporary copy, this doesn't do any allocation */
2792	static int early_mod_check(struct load_info *info, int flags)
2793	{
2794	int err;
2795
2796	/*
2797	* Now that we know we have the correct module name, check
2798	* if it's blacklisted.
2799	*/
2800	if (blacklisted(info->name)) {
2801	pr_err("Module %s is blacklisted\n", info->name);
2802	return -EPERM;
2803	}
2804
2805	err = rewrite_section_headers(info, flags);
2806	if (err)
2807	return err;
2808
2809	/* Check module struct version now, before we try to use module. */
2810	if (!check_modstruct_version(info, info->mod))
2811	return -ENOEXEC;
2812
2813	err = check_modinfo(info->mod, info, flags);
2814	if (err)
2815	return err;
2816
2817	mutex_lock(&module_mutex);
2818	err = module_patient_check_exists(info->mod->name, FAIL_DUP_MOD_BECOMING);
2819	mutex_unlock(&module_mutex);
2820
2821	return err;
2822	}
2823
2824	/*
2825	* Allocate and load the module: note that size of section 0 is always
2826	* zero, and we rely on this for optional sections.
2827	*/
2828	static int load_module(struct load_info info, const char __user uargs,
2829	int flags)
2830	{
2831	struct module *mod;
2832	bool module_allocated = false;
2833	long err = 0;
2834	char *after_dashes;
2835
2836	/*
2837	* Do the signature check (if any) first. All that
2838	* the signature check needs is info->len, it does
2839	* not need any of the section info. That can be
2840	* set up later. This will minimize the chances
2841	* of a corrupt module causing problems before
2842	* we even get to the signature check.
2843	*
2844	* The check will also adjust info->len by stripping
2845	* off the sig length at the end of the module, making
2846	* checks against info->len more correct.
2847	*/
2848	err = module_sig_check(info, flags);
2849	if (err)
2850	goto free_copy;
2851
2852	/*
2853	* Do basic sanity checks against the ELF header and
2854	* sections. Cache useful sections and set the
2855	* info->mod to the userspace passed struct module.
2856	*/
2857	err = elf_validity_cache_copy(info, flags);
2858	if (err)
2859	goto free_copy;
2860
2861	err = early_mod_check(info, flags);
2862	if (err)
2863	goto free_copy;
2864
2865	/* Figure out module layout, and allocate all the memory. */
2866	mod = layout_and_allocate(info, flags);
2867	if (IS_ERR(mod)) {
2868	err = PTR_ERR(mod);
2869	goto free_copy;
2870	}
2871
2872	module_allocated = true;
2873
2874	audit_log_kern_module(mod->name);
2875
2876	/* Reserve our place in the list. */
2877	err = add_unformed_module(mod);
2878	if (err)
2879	goto free_module;
2880
2881	/*
2882	* We are tainting your kernel if your module gets into
2883	* the modules linked list somehow.
2884	*/
2885	module_augment_kernel_taints(mod, info);
2886
2887	/* To avoid stressing percpu allocator, do this once we're unique. */
2888	err = percpu_modalloc(mod, info);
2889	if (err)
2890	goto unlink_mod;
2891
2892	/* Now module is in final location, initialize linked lists, etc. */
2893	err = module_unload_init(mod);
2894	if (err)
2895	goto unlink_mod;
2896
2897	init_param_lock(mod);
2898
2899	/*
2900	* Now we've got everything in the final locations, we can
2901	* find optional sections.
2902	*/
2903	err = find_module_sections(mod, info);
2904	if (err)
2905	goto free_unload;
2906
2907	err = check_export_symbol_versions(mod);
2908	if (err)
2909	goto free_unload;
2910
2911	/* Set up MODINFO_ATTR fields */
2912	setup_modinfo(mod, info);
2913
2914	/* Fix up syms, so that st_value is a pointer to location. */
2915	err = simplify_symbols(mod, info);
2916	if (err < 0)
2917	goto free_modinfo;
2918
2919	err = apply_relocations(mod, info);
2920	if (err < 0)
2921	goto free_modinfo;
2922
2923	err = post_relocation(mod, info);
2924	if (err < 0)
2925	goto free_modinfo;
2926
2927	flush_module_icache(mod);
2928
2929	/* Now copy in args */
2930	mod->args = strndup_user(uargs, ~0UL >> 1);
2931	if (IS_ERR(mod->args)) {
2932	err = PTR_ERR(mod->args);
2933	goto free_arch_cleanup;
2934	}
2935
2936	init_build_id(mod, info);
2937
2938	/* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
2939	ftrace_module_init(mod);
2940
2941	/* Finally it's fully formed, ready to start executing. */
2942	err = complete_formation(mod, info);
2943	if (err)
2944	goto ddebug_cleanup;
2945
2946	err = prepare_coming_module(mod);
2947	if (err)
2948	goto bug_cleanup;
2949
2950	mod->async_probe_requested = async_probe;
2951
2952	/* Module is ready to execute: parsing args may do that. */
2953	after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
2954	-32768, 32767, mod,
2955	unknown_module_param_cb);
2956	if (IS_ERR(after_dashes)) {
2957	err = PTR_ERR(after_dashes);
2958	goto coming_cleanup;
2959	} else if (after_dashes) {
2960	pr_warn("%s: parameters '%s' after `--' ignored\n",
2961	mod->name, after_dashes);
2962	}
2963
2964	/* Link in to sysfs. */
2965	err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
2966	if (err < 0)
2967	goto coming_cleanup;
2968
2969	if (is_livepatch_module(mod)) {
2970	err = copy_module_elf(mod, info);
2971	if (err < 0)
2972	goto sysfs_cleanup;
2973	}
2974
2975	/* Get rid of temporary copy. */
2976	free_copy(info, flags);
2977
2978	/* Done! */
2979	trace_module_load(mod);
2980
2981	return do_init_module(mod);
2982
2983	sysfs_cleanup:
2984	mod_sysfs_teardown(mod);
2985	coming_cleanup:
2986	mod->state = MODULE_STATE_GOING;
2987	destroy_params(mod->kp, mod->num_kp);
2988	blocking_notifier_call_chain(&module_notify_list,
2989	MODULE_STATE_GOING, mod);
2990	klp_module_going(mod);
2991	bug_cleanup:
2992	mod->state = MODULE_STATE_GOING;
2993	/* module_bug_cleanup needs module_mutex protection */
2994	mutex_lock(&module_mutex);
2995	module_bug_cleanup(mod);
2996	mutex_unlock(&module_mutex);
2997
2998	ddebug_cleanup:
2999	ftrace_release_mod(mod);
3000	synchronize_rcu();
3001	kfree(mod->args);
3002	free_arch_cleanup:
3003	module_arch_cleanup(mod);
3004	free_modinfo:
3005	free_modinfo(mod);
3006	free_unload:
3007	module_unload_free(mod);
3008	unlink_mod:
3009	mutex_lock(&module_mutex);
3010	/* Unlink carefully: kallsyms could be walking list. */
3011	list_del_rcu(&mod->list);
3012	mod_tree_remove(mod);
3013	wake_up_all(&module_wq);
3014	/* Wait for RCU-sched synchronizing before releasing mod->list. */
3015	synchronize_rcu();
3016	mutex_unlock(&module_mutex);
3017	free_module:
3018	mod_stat_bump_invalid(info, flags);
3019	/* Free lock-classes; relies on the preceding sync_rcu() */
3020	for_class_mod_mem_type(type, core_data) {
3021	lockdep_free_key_range(mod->mem[type].base,
3022	mod->mem[type].size);
3023	}
3024
3025	module_deallocate(mod, info);
3026	free_copy:
3027	/*
3028	* The info->len is always set. We distinguish between
3029	* failures once the proper module was allocated and
3030	* before that.
3031	*/
3032	if (!module_allocated)
3033	mod_stat_bump_becoming(info, flags);
3034	free_copy(info, flags);
3035	return err;
3036	}
3037
3038	SYSCALL_DEFINE3(init_module, void __user *, umod,
3039	unsigned long, len, const char __user *, uargs)
3040	{
3041	int err;
3042	struct load_info info = { };
3043
3044	err = may_init_module();
3045	if (err)
3046	return err;
3047
3048	pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3049	umod, len, uargs);
3050
3051	err = copy_module_from_user(umod, len, &info);
3052	if (err) {
3053	mod_stat_inc(&failed_kreads);
3054	mod_stat_add_long(len, &invalid_kread_bytes);
3055	return err;
3056	}
3057
3058	return load_module(&info, uargs, 0);
3059	}
3060
3061	struct idempotent {
3062	const void *cookie;
3063	struct hlist_node entry;
3064	struct completion complete;
3065	int ret;
3066	};
3067
3068	#define IDEM_HASH_BITS 8
3069	static struct hlist_head idem_hash[1 << IDEM_HASH_BITS];
3070	static DEFINE_SPINLOCK(idem_lock);
3071
3072	static bool idempotent(struct idempotent u, const void cookie)
3073	{
3074	int hash = hash_ptr(cookie, IDEM_HASH_BITS);
3075	struct hlist_head *head = idem_hash + hash;
3076	struct idempotent *existing;
3077	bool first;
3078
3079	u->ret = 0;
3080	u->cookie = cookie;
3081	init_completion(&u->complete);
3082
3083	spin_lock(&idem_lock);
3084	first = true;
3085	hlist_for_each_entry(existing, head, entry) {
3086	if (existing->cookie != cookie)
3087	continue;
3088	first = false;
3089	break;
3090	}
3091	hlist_add_head(&u->entry, idem_hash + hash);
3092	spin_unlock(&idem_lock);
3093
3094	return !first;
3095	}
3096
3097	/*
3098	* We were the first one with 'cookie' on the list, and we ended
3099	* up completing the operation. We now need to walk the list,
3100	* remove everybody - which includes ourselves - fill in the return
3101	* value, and then complete the operation.
3102	*/
3103	static int idempotent_complete(struct idempotent *u, int ret)
3104	{
3105	const void *cookie = u->cookie;
3106	int hash = hash_ptr(cookie, IDEM_HASH_BITS);
3107	struct hlist_head *head = idem_hash + hash;
3108	struct hlist_node *next;
3109	struct idempotent *pos;
3110
3111	spin_lock(&idem_lock);
3112	hlist_for_each_entry_safe(pos, next, head, entry) {
3113	if (pos->cookie != cookie)
3114	continue;
3115	hlist_del(&pos->entry);
3116	pos->ret = ret;
3117	complete(&pos->complete);
3118	}
3119	spin_unlock(&idem_lock);
3120	return ret;
3121	}
3122
3123	static int init_module_from_file(struct file f, const char __user uargs, int flags)
3124	{
3125	struct load_info info = { };
3126	void *buf = NULL;
3127	int len;
3128
3129	len = kernel_read_file(f, 0, &buf, INT_MAX, NULL, READING_MODULE);
3130	if (len < 0) {
3131	mod_stat_inc(&failed_kreads);
3132	return len;
3133	}
3134
3135	if (flags & MODULE_INIT_COMPRESSED_FILE) {
3136	int err = module_decompress(&info, buf, len);
3137	vfree(buf); /* compressed data is no longer needed */
3138	if (err) {
3139	mod_stat_inc(&failed_decompress);
3140	mod_stat_add_long(len, &invalid_decompress_bytes);
3141	return err;
3142	}
3143	} else {
3144	info.hdr = buf;
3145	info.len = len;
3146	}
3147
3148	return load_module(&info, uargs, flags);
3149	}
3150
3151	static int idempotent_init_module(struct file f, const char __user uargs, int flags)
3152	{
3153	struct idempotent idem;
3154
3155	if (!f \|\| !(f->f_mode & FMODE_READ))
3156	return -EBADF;
3157
3158	/* See if somebody else is doing the operation? */
3159	if (idempotent(&idem, file_inode(f))) {
3160	wait_for_completion(&idem.complete);
3161	return idem.ret;
3162	}
3163
3164	/* Otherwise, we'll do it and complete others */
3165	return idempotent_complete(&idem,
3166	init_module_from_file(f, uargs, flags));
3167	}
3168
3169	SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3170	{
3171	int err;
3172	struct fd f;
3173
3174	err = may_init_module();
3175	if (err)
3176	return err;
3177
3178	pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3179
3180	if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3181	\|MODULE_INIT_IGNORE_VERMAGIC
3182	\|MODULE_INIT_COMPRESSED_FILE))
3183	return -EINVAL;
3184
3185	f = fdget(fd);
3186	err = idempotent_init_module(f.file, uargs, flags);
3187	fdput(f);
3188	return err;
3189	}
3190
3191	/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
3192	char module_flags(struct module mod, char *buf, bool show_state)
3193	{
3194	int bx = 0;
3195
3196	BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3197	if (!mod->taints && !show_state)
3198	goto out;
3199	if (mod->taints \|\|
3200	mod->state == MODULE_STATE_GOING \|\|
3201	mod->state == MODULE_STATE_COMING) {
3202	buf[bx++] = '(';
3203	bx += module_flags_taint(mod->taints, buf + bx);
3204	/* Show a - for module-is-being-unloaded */
3205	if (mod->state == MODULE_STATE_GOING && show_state)
3206	buf[bx++] = '-';
3207	/* Show a + for module-is-being-loaded */
3208	if (mod->state == MODULE_STATE_COMING && show_state)
3209	buf[bx++] = '+';
3210	buf[bx++] = ')';
3211	}
3212	out:
3213	buf[bx] = '\0';
3214
3215	return buf;
3216	}
3217
3218	/* Given an address, look for it in the module exception tables. */
3219	const struct exception_table_entry *search_module_extables(unsigned long addr)
3220	{
3221	const struct exception_table_entry *e = NULL;
3222	struct module *mod;
3223
3224	preempt_disable();
3225	mod = __module_address(addr);
3226	if (!mod)
3227	goto out;
3228
3229	if (!mod->num_exentries)
3230	goto out;
3231
3232	e = search_extable(mod->extable,
3233	mod->num_exentries,
3234	addr);
3235	out:
3236	preempt_enable();
3237
3238	/*
3239	* Now, if we found one, we are running inside it now, hence
3240	* we cannot unload the module, hence no refcnt needed.
3241	*/
3242	return e;
3243	}
3244
3245	/**
3246	* is_module_address() - is this address inside a module?
3247	* @addr: the address to check.
3248	*
3249	* See is_module_text_address() if you simply want to see if the address
3250	* is code (not data).
3251	*/
3252	bool is_module_address(unsigned long addr)
3253	{
3254	bool ret;
3255
3256	preempt_disable();
3257	ret = __module_address(addr) != NULL;
3258	preempt_enable();
3259
3260	return ret;
3261	}
3262
3263	/**
3264	* __module_address() - get the module which contains an address.
3265	* @addr: the address.
3266	*
3267	* Must be called with preempt disabled or module mutex held so that
3268	* module doesn't get freed during this.
3269	*/
3270	struct module *__module_address(unsigned long addr)
3271	{
3272	struct module *mod;
3273
3274	if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max)
3275	goto lookup;
3276
3277	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
3278	if (addr >= mod_tree.data_addr_min && addr <= mod_tree.data_addr_max)
3279	goto lookup;
3280	#endif
3281
3282	return NULL;
3283
3284	lookup:
3285	module_assert_mutex_or_preempt();
3286
3287	mod = mod_find(addr, &mod_tree);
3288	if (mod) {
3289	BUG_ON(!within_module(addr, mod));
3290	if (mod->state == MODULE_STATE_UNFORMED)
3291	mod = NULL;
3292	}
3293	return mod;
3294	}
3295
3296	/**
3297	* is_module_text_address() - is this address inside module code?
3298	* @addr: the address to check.
3299	*
3300	* See is_module_address() if you simply want to see if the address is
3301	* anywhere in a module. See kernel_text_address() for testing if an
3302	* address corresponds to kernel or module code.
3303	*/
3304	bool is_module_text_address(unsigned long addr)
3305	{
3306	bool ret;
3307
3308	preempt_disable();
3309	ret = __module_text_address(addr) != NULL;
3310	preempt_enable();
3311
3312	return ret;
3313	}
3314
3315	/**
3316	* __module_text_address() - get the module whose code contains an address.
3317	* @addr: the address.
3318	*
3319	* Must be called with preempt disabled or module mutex held so that
3320	* module doesn't get freed during this.
3321	*/
3322	struct module *__module_text_address(unsigned long addr)
3323	{
3324	struct module *mod = __module_address(addr);
3325	if (mod) {
3326	/* Make sure it's within the text section. */
3327	if (!within_module_mem_type(addr, mod, MOD_TEXT) &&
3328	!within_module_mem_type(addr, mod, MOD_INIT_TEXT))
3329	mod = NULL;
3330	}
3331	return mod;
3332	}
3333
3334	/* Don't grab lock, we're oopsing. */
3335	void print_modules(void)
3336	{
3337	struct module *mod;
3338	char buf[MODULE_FLAGS_BUF_SIZE];
3339
3340	printk(KERN_DEFAULT "Modules linked in:");
3341	/* Most callers should already have preempt disabled, but make sure */
3342	preempt_disable();
3343	list_for_each_entry_rcu(mod, &modules, list) {
3344	if (mod->state == MODULE_STATE_UNFORMED)
3345	continue;
3346	pr_cont(" %s%s", mod->name, module_flags(mod, buf, true));
3347	}
3348
3349	print_unloaded_tainted_modules();
3350	preempt_enable();
3351	if (last_unloaded_module.name[0])
3352	pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name,
3353	last_unloaded_module.taints);
3354	pr_cont("\n");
3355	}
3356
3357	#ifdef CONFIG_MODULE_DEBUGFS
3358	struct dentry *mod_debugfs_root;
3359
3360	static int module_debugfs_init(void)
3361	{
3362	mod_debugfs_root = debugfs_create_dir("modules", NULL);
3363	return 0;
3364	}
3365	module_init(module_debugfs_init);
3366	#endif