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 <mcgrof@kernel.org>
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/codetag.h>
60	#include <linux/debugfs.h>
61	#include <linux/execmem.h>
62	#include <uapi/linux/module.h>
63	#include "internal.h"
64
65	#define CREATE_TRACE_POINTS
66	#include <trace/events/module.h>
67
68	/*
69	* Mutex protects:
70	* 1) List of modules (also safely readable within RCU read section),
71	* 2) module_use links,
72	* 3) mod_tree.addr_min/mod_tree.addr_max.
73	* (delete and add uses RCU list operations).
74	*/
75	DEFINE_MUTEX(module_mutex);
76	LIST_HEAD(modules);
77
78	/* Work queue for freeing init sections in success case */
79	static void do_free_init(struct work_struct *w);
80	static DECLARE_WORK(init_free_wq, do_free_init);
81	static LLIST_HEAD(init_free_list);
82
83	struct mod_tree_root mod_tree __cacheline_aligned = {
84	.addr_min = -1UL,
85	};
86
87	struct symsearch {
88	const struct kernel_symbol *start, *stop;
89	const u32 *crcs;
90	enum mod_license license;
91	};
92
93	/*
94	* Bounds of module memory, for speeding up __module_address.
95	* Protected by module_mutex.
96	*/
97	static void __mod_update_bounds(enum mod_mem_type type __maybe_unused, void *base,
98	unsigned int size, struct mod_tree_root *tree)
99	{
100	unsigned long min = (unsigned long)base;
101	unsigned long max = min + size;
102
103	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
104	if (mod_mem_type_is_core_data(type)) {
105	if (min < tree->data_addr_min)
106	tree->data_addr_min = min;
107	if (max > tree->data_addr_max)
108	tree->data_addr_max = max;
109	return;
110	}
111	#endif
112	if (min < tree->addr_min)
113	tree->addr_min = min;
114	if (max > tree->addr_max)
115	tree->addr_max = max;
116	}
117
118	static void mod_update_bounds(struct module *mod)
119	{
120	for_each_mod_mem_type(type) {
121	struct module_memory *mod_mem = &mod->mem[type];
122
123	if (mod_mem->size)
124	__mod_update_bounds(type, base: mod_mem->base, size: mod_mem->size, tree: &mod_tree);
125	}
126	}
127
128	/* Block module loading/unloading? */
129	int modules_disabled;
130	core_param(nomodule, modules_disabled, bint, 0);
131
132	/* Waiting for a module to finish initializing? */
133	static DECLARE_WAIT_QUEUE_HEAD(module_wq);
134
135	static BLOCKING_NOTIFIER_HEAD(module_notify_list);
136
137	int register_module_notifier(struct notifier_block *nb)
138	{
139	return blocking_notifier_chain_register(nh: &module_notify_list, nb);
140	}
141	EXPORT_SYMBOL(register_module_notifier);
142
143	int unregister_module_notifier(struct notifier_block *nb)
144	{
145	return blocking_notifier_chain_unregister(nh: &module_notify_list, nb);
146	}
147	EXPORT_SYMBOL(unregister_module_notifier);
148
149	/*
150	* We require a truly strong try_module_get(): 0 means success.
151	* Otherwise an error is returned due to ongoing or failed
152	* initialization etc.
153	*/
154	static inline int strong_try_module_get(struct module *mod)
155	{
156	BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
157	if (mod && mod->state == MODULE_STATE_COMING)
158	return -EBUSY;
159	if (try_module_get(module: mod))
160	return 0;
161	else
162	return -ENOENT;
163	}
164
165	static inline void add_taint_module(struct module *mod, unsigned flag,
166	enum lockdep_ok lockdep_ok)
167	{
168	add_taint(flag, lockdep_ok);
169	set_bit(nr: flag, addr: &mod->taints);
170	}
171
172	/*
173	* Like strncmp(), except s/-/_/g as per scripts/Makefile.lib:name-fix-token rule.
174	*/
175	static int mod_strncmp(const char *str_a, const char *str_b, size_t n)
176	{
177	for (int i = 0; i < n; i++) {
178	char a = str_a[i];
179	char b = str_b[i];
180	int d;
181
182	if (a == '-') a = '_';
183	if (b == '-') b = '_';
184
185	d = a - b;
186	if (d)
187	return d;
188
189	if (!a)
190	break;
191	}
192
193	return 0;
194	}
195
196	/*
197	* A thread that wants to hold a reference to a module only while it
198	* is running can call this to safely exit.
199	*/
200	void __noreturn __module_put_and_kthread_exit(struct module *mod, long code)
201	{
202	module_put(module: mod);
203	kthread_exit(result: code);
204	}
205	EXPORT_SYMBOL(__module_put_and_kthread_exit);
206
207	/* Find a module section: 0 means not found. */
208	static unsigned int find_sec(const struct load_info *info, const char *name)
209	{
210	unsigned int i;
211
212	for (i = 1; i < info->hdr->e_shnum; i++) {
213	Elf_Shdr *shdr = &info->sechdrs[i];
214	/* Alloc bit cleared means "ignore it." */
215	if ((shdr->sh_flags & SHF_ALLOC)
216	&& strcmp(info->secstrings + shdr->sh_name, name) == 0)
217	return i;
218	}
219	return 0;
220	}
221
222	/**
223	* find_any_unique_sec() - Find a unique section index by name
224	* @info: Load info for the module to scan
225	* @name: Name of the section we're looking for
226	*
227	* Locates a unique section by name. Ignores SHF_ALLOC.
228	*
229	* Return: Section index if found uniquely, zero if absent, negative count
230	* of total instances if multiple were found.
231	*/
232	static int find_any_unique_sec(const struct load_info *info, const char *name)
233	{
234	unsigned int idx;
235	unsigned int count = 0;
236	int i;
237
238	for (i = 1; i < info->hdr->e_shnum; i++) {
239	if (strcmp(info->secstrings + info->sechdrs[i].sh_name,
240	name) == 0) {
241	count++;
242	idx = i;
243	}
244	}
245	if (count == 1) {
246	return idx;
247	} else if (count == 0) {
248	return 0;
249	} else {
250	return -count;
251	}
252	}
253
254	/* Find a module section, or NULL. */
255	static void *section_addr(const struct load_info *info, const char *name)
256	{
257	/* Section 0 has sh_addr 0. */
258	return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
259	}
260
261	/* Find a module section, or NULL. Fill in number of "objects" in section. */
262	static void *section_objs(const struct load_info *info,
263	const char *name,
264	size_t object_size,
265	unsigned int *num)
266	{
267	unsigned int sec = find_sec(info, name);
268
269	/* Section 0 has sh_addr 0 and sh_size 0. */
270	*num = info->sechdrs[sec].sh_size / object_size;
271	return (void *)info->sechdrs[sec].sh_addr;
272	}
273
274	/* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */
275	static unsigned int find_any_sec(const struct load_info *info, const char *name)
276	{
277	unsigned int i;
278
279	for (i = 1; i < info->hdr->e_shnum; i++) {
280	Elf_Shdr *shdr = &info->sechdrs[i];
281	if (strcmp(info->secstrings + shdr->sh_name, name) == 0)
282	return i;
283	}
284	return 0;
285	}
286
287	/*
288	* Find a module section, or NULL. Fill in number of "objects" in section.
289	* Ignores SHF_ALLOC flag.
290	*/
291	static __maybe_unused void *any_section_objs(const struct load_info *info,
292	const char *name,
293	size_t object_size,
294	unsigned int *num)
295	{
296	unsigned int sec = find_any_sec(info, name);
297
298	/* Section 0 has sh_addr 0 and sh_size 0. */
299	*num = info->sechdrs[sec].sh_size / object_size;
300	return (void *)info->sechdrs[sec].sh_addr;
301	}
302
303	#ifndef CONFIG_MODVERSIONS
304	#define symversion(base, idx) NULL
305	#else
306	#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
307	#endif
308
309	static const char *kernel_symbol_name(const struct kernel_symbol *sym)
310	{
311	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
312	return offset_to_ptr(off: &sym->name_offset);
313	#else
314	return sym->name;
315	#endif
316	}
317
318	static const char *kernel_symbol_namespace(const struct kernel_symbol *sym)
319	{
320	#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
321	if (!sym->namespace_offset)
322	return NULL;
323	return offset_to_ptr(off: &sym->namespace_offset);
324	#else
325	return sym->namespace;
326	#endif
327	}
328
329	int cmp_name(const void *name, const void *sym)
330	{
331	return strcmp(name, kernel_symbol_name(sym));
332	}
333
334	static bool find_exported_symbol_in_section(const struct symsearch *syms,
335	struct module *owner,
336	struct find_symbol_arg *fsa)
337	{
338	struct kernel_symbol *sym;
339
340	if (!fsa->gplok && syms->license == GPL_ONLY)
341	return false;
342
343	sym = bsearch(key: fsa->name, base: syms->start, num: syms->stop - syms->start,
344	size: sizeof(struct kernel_symbol), cmp: cmp_name);
345	if (!sym)
346	return false;
347
348	fsa->owner = owner;
349	fsa->crc = symversion(syms->crcs, sym - syms->start);
350	fsa->sym = sym;
351	fsa->license = syms->license;
352
353	return true;
354	}
355
356	/*
357	* Find an exported symbol and return it, along with, (optional) crc and
358	* (optional) module which owns it. Needs RCU or module_mutex.
359	*/
360	bool find_symbol(struct find_symbol_arg *fsa)
361	{
362	static const struct symsearch arr[] = {
363	{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
364	NOT_GPL_ONLY },
365	{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
366	__start___kcrctab_gpl,
367	GPL_ONLY },
368	};
369	struct module *mod;
370	unsigned int i;
371
372	for (i = 0; i < ARRAY_SIZE(arr); i++)
373	if (find_exported_symbol_in_section(syms: &arr[i], NULL, fsa))
374	return true;
375
376	list_for_each_entry_rcu(mod, &modules, list,
377	lockdep_is_held(&module_mutex)) {
378	struct symsearch arr[] = {
379	{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
380	NOT_GPL_ONLY },
381	{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
382	mod->gpl_crcs,
383	GPL_ONLY },
384	};
385
386	if (mod->state == MODULE_STATE_UNFORMED)
387	continue;
388
389	for (i = 0; i < ARRAY_SIZE(arr); i++)
390	if (find_exported_symbol_in_section(syms: &arr[i], owner: mod, fsa))
391	return true;
392	}
393
394	pr_debug("Failed to find symbol %s\n", fsa->name);
395	return false;
396	}
397
398	/*
399	* Search for module by name: must hold module_mutex (or RCU for read-only
400	* access).
401	*/
402	struct module *find_module_all(const char *name, size_t len,
403	bool even_unformed)
404	{
405	struct module *mod;
406
407	list_for_each_entry_rcu(mod, &modules, list,
408	lockdep_is_held(&module_mutex)) {
409	if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
410	continue;
411	if (strlen(mod->name) == len && !memcmp(p: mod->name, q: name, size: len))
412	return mod;
413	}
414	return NULL;
415	}
416
417	struct module *find_module(const char *name)
418	{
419	return find_module_all(name, strlen(name), even_unformed: false);
420	}
421
422	#ifdef CONFIG_SMP
423
424	static inline void __percpu *mod_percpu(struct module *mod)
425	{
426	return mod->percpu;
427	}
428
429	static int percpu_modalloc(struct module *mod, struct load_info *info)
430	{
431	Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
432	unsigned long align = pcpusec->sh_addralign;
433
434	if (!pcpusec->sh_size)
435	return 0;
436
437	if (align > PAGE_SIZE) {
438	pr_warn("%s: per-cpu alignment %li > %li\n",
439	mod->name, align, PAGE_SIZE);
440	align = PAGE_SIZE;
441	}
442
443	mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
444	if (!mod->percpu) {
445	pr_warn("%s: Could not allocate %lu bytes percpu data\n",
446	mod->name, (unsigned long)pcpusec->sh_size);
447	return -ENOMEM;
448	}
449	mod->percpu_size = pcpusec->sh_size;
450	return 0;
451	}
452
453	static void percpu_modfree(struct module *mod)
454	{
455	free_percpu(pdata: mod->percpu);
456	}
457
458	static unsigned int find_pcpusec(struct load_info *info)
459	{
460	return find_sec(info, name: ".data..percpu");
461	}
462
463	static void percpu_modcopy(struct module *mod,
464	const void *from, unsigned long size)
465	{
466	int cpu;
467
468	for_each_possible_cpu(cpu)
469	memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
470	}
471
472	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
473	{
474	struct module *mod;
475	unsigned int cpu;
476
477	guard(rcu)();
478	list_for_each_entry_rcu(mod, &modules, list) {
479	if (mod->state == MODULE_STATE_UNFORMED)
480	continue;
481	if (!mod->percpu_size)
482	continue;
483	for_each_possible_cpu(cpu) {
484	void *start = per_cpu_ptr(mod->percpu, cpu);
485	void *va = (void *)addr;
486
487	if (va >= start && va < start + mod->percpu_size) {
488	if (can_addr) {
489	*can_addr = (unsigned long) (va - start);
490	*can_addr += (unsigned long)
491	per_cpu_ptr(mod->percpu,
492	get_boot_cpu_id());
493	}
494	return true;
495	}
496	}
497	}
498	return false;
499	}
500
501	/**
502	* is_module_percpu_address() - test whether address is from module static percpu
503	* @addr: address to test
504	*
505	* Test whether @addr belongs to module static percpu area.
506	*
507	* Return: %true if @addr is from module static percpu area
508	*/
509	bool is_module_percpu_address(unsigned long addr)
510	{
511	return __is_module_percpu_address(addr, NULL);
512	}
513
514	#else /* ... !CONFIG_SMP */
515
516	static inline void __percpu *mod_percpu(struct module *mod)
517	{
518	return NULL;
519	}
520	static int percpu_modalloc(struct module *mod, struct load_info *info)
521	{
522	/* UP modules shouldn't have this section: ENOMEM isn't quite right */
523	if (info->sechdrs[info->index.pcpu].sh_size != 0)
524	return -ENOMEM;
525	return 0;
526	}
527	static inline void percpu_modfree(struct module *mod)
528	{
529	}
530	static unsigned int find_pcpusec(struct load_info *info)
531	{
532	return 0;
533	}
534	static inline void percpu_modcopy(struct module *mod,
535	const void *from, unsigned long size)
536	{
537	/* pcpusec should be 0, and size of that section should be 0. */
538	BUG_ON(size != 0);
539	}
540	bool is_module_percpu_address(unsigned long addr)
541	{
542	return false;
543	}
544
545	bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
546	{
547	return false;
548	}
549
550	#endif /* CONFIG_SMP */
551
552	#define MODINFO_ATTR(field) \
553	static void setup_modinfo_##field(struct module *mod, const char *s) \
554	{ \
555	mod->field = kstrdup(s, GFP_KERNEL); \
556	} \
557	static ssize_t show_modinfo_##field(const struct module_attribute *mattr, \
558	struct module_kobject *mk, char *buffer) \
559	{ \
560	return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
561	} \
562	static int modinfo_##field##_exists(struct module *mod) \
563	{ \
564	return mod->field != NULL; \
565	} \
566	static void free_modinfo_##field(struct module *mod) \
567	{ \
568	kfree(mod->field); \
569	mod->field = NULL; \
570	} \
571	static const struct module_attribute modinfo_##field = { \
572	.attr = { .name = __stringify(field), .mode = 0444 }, \
573	.show = show_modinfo_##field, \
574	.setup = setup_modinfo_##field, \
575	.test = modinfo_##field##_exists, \
576	.free = free_modinfo_##field, \
577	};
578
579	MODINFO_ATTR(version);
580	MODINFO_ATTR(srcversion);
581
582	static struct {
583	char name[MODULE_NAME_LEN + 1];
584	char taints[MODULE_FLAGS_BUF_SIZE];
585	} last_unloaded_module;
586
587	#ifdef CONFIG_MODULE_UNLOAD
588
589	EXPORT_TRACEPOINT_SYMBOL(module_get);
590
591	/* MODULE_REF_BASE is the base reference count by kmodule loader. */
592	#define MODULE_REF_BASE 1
593
594	/* Init the unload section of the module. */
595	static int module_unload_init(struct module *mod)
596	{
597	/*
598	* Initialize reference counter to MODULE_REF_BASE.
599	* refcnt == 0 means module is going.
600	*/
601	atomic_set(v: &mod->refcnt, MODULE_REF_BASE);
602
603	INIT_LIST_HEAD(list: &mod->source_list);
604	INIT_LIST_HEAD(list: &mod->target_list);
605
606	/* Hold reference count during initialization. */
607	atomic_inc(v: &mod->refcnt);
608
609	return 0;
610	}
611
612	/* Does a already use b? */
613	static int already_uses(struct module *a, struct module *b)
614	{
615	struct module_use *use;
616
617	list_for_each_entry(use, &b->source_list, source_list) {
618	if (use->source == a)
619	return 1;
620	}
621	pr_debug("%s does not use %s!\n", a->name, b->name);
622	return 0;
623	}
624
625	/*
626	* Module a uses b
627	* - we add 'a' as a "source", 'b' as a "target" of module use
628	* - the module_use is added to the list of 'b' sources (so
629	* 'b' can walk the list to see who sourced them), and of 'a'
630	* targets (so 'a' can see what modules it targets).
631	*/
632	static int add_module_usage(struct module *a, struct module *b)
633	{
634	struct module_use *use;
635
636	pr_debug("Allocating new usage for %s.\n", a->name);
637	use = kmalloc(sizeof(*use), GFP_ATOMIC);
638	if (!use)
639	return -ENOMEM;
640
641	use->source = a;
642	use->target = b;
643	list_add(new: &use->source_list, head: &b->source_list);
644	list_add(new: &use->target_list, head: &a->target_list);
645	return 0;
646	}
647
648	/* Module a uses b: caller needs module_mutex() */
649	static int ref_module(struct module *a, struct module *b)
650	{
651	int err;
652
653	if (b == NULL || already_uses(a, b))
654	return 0;
655
656	/* If module isn't available, we fail. */
657	err = strong_try_module_get(mod: b);
658	if (err)
659	return err;
660
661	err = add_module_usage(a, b);
662	if (err) {
663	module_put(module: b);
664	return err;
665	}
666	return 0;
667	}
668
669	/* Clear the unload stuff of the module. */
670	static void module_unload_free(struct module *mod)
671	{
672	struct module_use *use, *tmp;
673
674	mutex_lock(&module_mutex);
675	list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
676	struct module *i = use->target;
677	pr_debug("%s unusing %s\n", mod->name, i->name);
678	module_put(module: i);
679	list_del(entry: &use->source_list);
680	list_del(entry: &use->target_list);
681	kfree(objp: use);
682	}
683	mutex_unlock(lock: &module_mutex);
684	}
685
686	#ifdef CONFIG_MODULE_FORCE_UNLOAD
687	static inline int try_force_unload(unsigned int flags)
688	{
689	int ret = (flags & O_TRUNC);
690	if (ret)
691	add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
692	return ret;
693	}
694	#else
695	static inline int try_force_unload(unsigned int flags)
696	{
697	return 0;
698	}
699	#endif /* CONFIG_MODULE_FORCE_UNLOAD */
700
701	/* Try to release refcount of module, 0 means success. */
702	static int try_release_module_ref(struct module *mod)
703	{
704	int ret;
705
706	/* Try to decrement refcnt which we set at loading */
707	ret = atomic_sub_return(MODULE_REF_BASE, v: &mod->refcnt);
708	BUG_ON(ret < 0);
709	if (ret)
710	/* Someone can put this right now, recover with checking */
711	ret = atomic_add_unless(v: &mod->refcnt, MODULE_REF_BASE, u: 0);
712
713	return ret;
714	}
715
716	static int try_stop_module(struct module *mod, int flags, int *forced)
717	{
718	/* If it's not unused, quit unless we're forcing. */
719	if (try_release_module_ref(mod) != 0) {
720	*forced = try_force_unload(flags);
721	if (!(*forced))
722	return -EWOULDBLOCK;
723	}
724
725	/* Mark it as dying. */
726	mod->state = MODULE_STATE_GOING;
727
728	return 0;
729	}
730
731	/**
732	* module_refcount() - return the refcount or -1 if unloading
733	* @mod: the module we're checking
734	*
735	* Return:
736	* -1 if the module is in the process of unloading
737	* otherwise the number of references in the kernel to the module
738	*/
739	int module_refcount(struct module *mod)
740	{
741	return atomic_read(v: &mod->refcnt) - MODULE_REF_BASE;
742	}
743	EXPORT_SYMBOL(module_refcount);
744
745	/* This exists whether we can unload or not */
746	static void free_module(struct module *mod);
747
748	SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
749	unsigned int, flags)
750	{
751	struct module *mod;
752	char name[MODULE_NAME_LEN];
753	char buf[MODULE_FLAGS_BUF_SIZE];
754	int ret, forced = 0;
755
756	if (!capable(CAP_SYS_MODULE) || modules_disabled)
757	return -EPERM;
758
759	if (strncpy_from_user(dst: name, src: name_user, MODULE_NAME_LEN-1) < 0)
760	return -EFAULT;
761	name[MODULE_NAME_LEN-1] = '\0';
762
763	audit_log_kern_module(name);
764
765	if (mutex_lock_interruptible(&module_mutex) != 0)
766	return -EINTR;
767
768	mod = find_module(name);
769	if (!mod) {
770	ret = -ENOENT;
771	goto out;
772	}
773
774	if (!list_empty(head: &mod->source_list)) {
775	/* Other modules depend on us: get rid of them first. */
776	ret = -EWOULDBLOCK;
777	goto out;
778	}
779
780	/* Doing init or already dying? */
781	if (mod->state != MODULE_STATE_LIVE) {
782	/* FIXME: if (force), slam module count damn the torpedoes */
783	pr_debug("%s already dying\n", mod->name);
784	ret = -EBUSY;
785	goto out;
786	}
787
788	/* If it has an init func, it must have an exit func to unload */
789	if (mod->init && !mod->exit) {
790	forced = try_force_unload(flags);
791	if (!forced) {
792	/* This module can't be removed */
793	ret = -EBUSY;
794	goto out;
795	}
796	}
797
798	ret = try_stop_module(mod, flags, forced: &forced);
799	if (ret != 0)
800	goto out;
801
802	mutex_unlock(lock: &module_mutex);
803	/* Final destruction now no one is using it. */
804	if (mod->exit != NULL)
805	mod->exit();
806	blocking_notifier_call_chain(nh: &module_notify_list,
807	val: MODULE_STATE_GOING, v: mod);
808	klp_module_going(mod);
809	ftrace_release_mod(mod);
810
811	async_synchronize_full();
812
813	/* Store the name and taints of the last unloaded module for diagnostic purposes */
814	strscpy(last_unloaded_module.name, mod->name);
815	strscpy(last_unloaded_module.taints, module_flags(mod, buf, false));
816
817	free_module(mod);
818	/* someone could wait for the module in add_unformed_module() */
819	wake_up_all(&module_wq);
820	return 0;
821	out:
822	mutex_unlock(lock: &module_mutex);
823	return ret;
824	}
825
826	void __symbol_put(const char *symbol)
827	{
828	struct find_symbol_arg fsa = {
829	.name = symbol,
830	.gplok = true,
831	};
832
833	guard(rcu)();
834	BUG_ON(!find_symbol(&fsa));
835	module_put(module: fsa.owner);
836	}
837	EXPORT_SYMBOL(__symbol_put);
838
839	/* Note this assumes addr is a function, which it currently always is. */
840	void symbol_put_addr(void *addr)
841	{
842	struct module *modaddr;
843	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
844
845	if (core_kernel_text(addr: a))
846	return;
847
848	/*
849	* Even though we hold a reference on the module; we still need to
850	* RCU read section in order to safely traverse the data structure.
851	*/
852	guard(rcu)();
853	modaddr = __module_text_address(addr: a);
854	BUG_ON(!modaddr);
855	module_put(module: modaddr);
856	}
857	EXPORT_SYMBOL_GPL(symbol_put_addr);
858
859	static ssize_t show_refcnt(const struct module_attribute *mattr,
860	struct module_kobject *mk, char *buffer)
861	{
862	return sprintf(buf: buffer, fmt: "%i\n", module_refcount(mk->mod));
863	}
864
865	static const struct module_attribute modinfo_refcnt =
866	__ATTR(refcnt, 0444, show_refcnt, NULL);
867
868	void __module_get(struct module *module)
869	{
870	if (module) {
871	atomic_inc(v: &module->refcnt);
872	trace_module_get(mod: module, _RET_IP_);
873	}
874	}
875	EXPORT_SYMBOL(__module_get);
876
877	bool try_module_get(struct module *module)
878	{
879	bool ret = true;
880
881	if (module) {
882	/* Note: here, we can fail to get a reference */
883	if (likely(module_is_live(module) &&
884	atomic_inc_not_zero(&module->refcnt) != 0))
885	trace_module_get(mod: module, _RET_IP_);
886	else
887	ret = false;
888	}
889	return ret;
890	}
891	EXPORT_SYMBOL(try_module_get);
892
893	void module_put(struct module *module)
894	{
895	int ret;
896
897	if (module) {
898	ret = atomic_dec_if_positive(v: &module->refcnt);
899	WARN_ON(ret < 0); /* Failed to put refcount */
900	trace_module_put(mod: module, _RET_IP_);
901	}
902	}
903	EXPORT_SYMBOL(module_put);
904
905	#else /* !CONFIG_MODULE_UNLOAD */
906	static inline void module_unload_free(struct module *mod)
907	{
908	}
909
910	static int ref_module(struct module *a, struct module *b)
911	{
912	return strong_try_module_get(b);
913	}
914
915	static inline int module_unload_init(struct module *mod)
916	{
917	return 0;
918	}
919	#endif /* CONFIG_MODULE_UNLOAD */
920
921	size_t module_flags_taint(unsigned long taints, char *buf)
922	{
923	size_t l = 0;
924	int i;
925
926	for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
927	if (taint_flags[i].module && test_bit(i, &taints))
928	buf[l++] = taint_flags[i].c_true;
929	}
930
931	return l;
932	}
933
934	static ssize_t show_initstate(const struct module_attribute *mattr,
935	struct module_kobject *mk, char *buffer)
936	{
937	const char *state = "unknown";
938
939	switch (mk->mod->state) {
940	case MODULE_STATE_LIVE:
941	state = "live";
942	break;
943	case MODULE_STATE_COMING:
944	state = "coming";
945	break;
946	case MODULE_STATE_GOING:
947	state = "going";
948	break;
949	default:
950	BUG();
951	}
952	return sprintf(buf: buffer, fmt: "%s\n", state);
953	}
954
955	static const struct module_attribute modinfo_initstate =
956	__ATTR(initstate, 0444, show_initstate, NULL);
957
958	static ssize_t store_uevent(const struct module_attribute *mattr,
959	struct module_kobject *mk,
960	const char *buffer, size_t count)
961	{
962	int rc;
963
964	rc = kobject_synth_uevent(kobj: &mk->kobj, buf: buffer, count);
965	return rc ? rc : count;
966	}
967
968	const struct module_attribute module_uevent =
969	__ATTR(uevent, 0200, NULL, store_uevent);
970
971	static ssize_t show_coresize(const struct module_attribute *mattr,
972	struct module_kobject *mk, char *buffer)
973	{
974	unsigned int size = mk->mod->mem[MOD_TEXT].size;
975
976	if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) {
977	for_class_mod_mem_type(type, core_data)
978	size += mk->mod->mem[type].size;
979	}
980	return sprintf(buf: buffer, fmt: "%u\n", size);
981	}
982
983	static const struct module_attribute modinfo_coresize =
984	__ATTR(coresize, 0444, show_coresize, NULL);
985
986	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
987	static ssize_t show_datasize(const struct module_attribute *mattr,
988	struct module_kobject *mk, char *buffer)
989	{
990	unsigned int size = 0;
991
992	for_class_mod_mem_type(type, core_data)
993	size += mk->mod->mem[type].size;
994	return sprintf(buffer, "%u\n", size);
995	}
996
997	static const struct module_attribute modinfo_datasize =
998	__ATTR(datasize, 0444, show_datasize, NULL);
999	#endif
1000
1001	static ssize_t show_initsize(const struct module_attribute *mattr,
1002	struct module_kobject *mk, char *buffer)
1003	{
1004	unsigned int size = 0;
1005
1006	for_class_mod_mem_type(type, init)
1007	size += mk->mod->mem[type].size;
1008	return sprintf(buf: buffer, fmt: "%u\n", size);
1009	}
1010
1011	static const struct module_attribute modinfo_initsize =
1012	__ATTR(initsize, 0444, show_initsize, NULL);
1013
1014	static ssize_t show_taint(const struct module_attribute *mattr,
1015	struct module_kobject *mk, char *buffer)
1016	{
1017	size_t l;
1018
1019	l = module_flags_taint(taints: mk->mod->taints, buf: buffer);
1020	buffer[l++] = '\n';
1021	return l;
1022	}
1023
1024	static const struct module_attribute modinfo_taint =
1025	__ATTR(taint, 0444, show_taint, NULL);
1026
1027	const struct module_attribute *const modinfo_attrs[] = {
1028	&module_uevent,
1029	&modinfo_version,
1030	&modinfo_srcversion,
1031	&modinfo_initstate,
1032	&modinfo_coresize,
1033	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
1034	&modinfo_datasize,
1035	#endif
1036	&modinfo_initsize,
1037	&modinfo_taint,
1038	#ifdef CONFIG_MODULE_UNLOAD
1039	&modinfo_refcnt,
1040	#endif
1041	NULL,
1042	};
1043
1044	const size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);
1045
1046	static const char vermagic[] = VERMAGIC_STRING;
1047
1048	int try_to_force_load(struct module *mod, const char *reason)
1049	{
1050	#ifdef CONFIG_MODULE_FORCE_LOAD
1051	if (!test_taint(TAINT_FORCED_MODULE))
1052	pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
1053	add_taint_module(mod, TAINT_FORCED_MODULE, lockdep_ok: LOCKDEP_NOW_UNRELIABLE);
1054	return 0;
1055	#else
1056	return -ENOEXEC;
1057	#endif
1058	}
1059
1060	/* Parse tag=value strings from .modinfo section */
1061	char *module_next_tag_pair(char *string, unsigned long *secsize)
1062	{
1063	/* Skip non-zero chars */
1064	while (string[0]) {
1065	string++;
1066	if ((*secsize)-- <= 1)
1067	return NULL;
1068	}
1069
1070	/* Skip any zero padding. */
1071	while (!string[0]) {
1072	string++;
1073	if ((*secsize)-- <= 1)
1074	return NULL;
1075	}
1076	return string;
1077	}
1078
1079	static char *get_next_modinfo(const struct load_info *info, const char *tag,
1080	char *prev)
1081	{
1082	char *p;
1083	unsigned int taglen = strlen(tag);
1084	Elf_Shdr *infosec = &info->sechdrs[info->index.info];
1085	unsigned long size = infosec->sh_size;
1086
1087	/*
1088	* get_modinfo() calls made before rewrite_section_headers()
1089	* must use sh_offset, as sh_addr isn't set!
1090	*/
1091	char *modinfo = (char *)info->hdr + infosec->sh_offset;
1092
1093	if (prev) {
1094	size -= prev - modinfo;
1095	modinfo = module_next_tag_pair(string: prev, secsize: &size);
1096	}
1097
1098	for (p = modinfo; p; p = module_next_tag_pair(string: p, secsize: &size)) {
1099	if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
1100	return p + taglen + 1;
1101	}
1102	return NULL;
1103	}
1104
1105	static char *get_modinfo(const struct load_info *info, const char *tag)
1106	{
1107	return get_next_modinfo(info, tag, NULL);
1108	}
1109
1110	/**
1111	* verify_module_namespace() - does @modname have access to this symbol's @namespace
1112	* @namespace: export symbol namespace
1113	* @modname: module name
1114	*
1115	* If @namespace is prefixed with "module:" to indicate it is a module namespace
1116	* then test if @modname matches any of the comma separated patterns.
1117	*
1118	* The patterns only support tail-glob.
1119	*/
1120	static bool verify_module_namespace(const char *namespace, const char *modname)
1121	{
1122	size_t len, modlen = strlen(modname);
1123	const char *prefix = "module:";
1124	const char *sep;
1125	bool glob;
1126
1127	if (!strstarts(str: namespace, prefix))
1128	return false;
1129
1130	for (namespace += strlen(prefix); *namespace; namespace = sep) {
1131	sep = strchrnul(namespace, ',');
1132	len = sep - namespace;
1133
1134	glob = false;
1135	if (sep[-1] == '*') {
1136	len--;
1137	glob = true;
1138	}
1139
1140	if (*sep)
1141	sep++;
1142
1143	if (mod_strncmp(str_a: namespace, str_b: modname, n: len) == 0 && (glob || len == modlen))
1144	return true;
1145	}
1146
1147	return false;
1148	}
1149
1150	static int verify_namespace_is_imported(const struct load_info *info,
1151	const struct kernel_symbol *sym,
1152	struct module *mod)
1153	{
1154	const char *namespace;
1155	char *imported_namespace;
1156
1157	namespace = kernel_symbol_namespace(sym);
1158	if (namespace && namespace[0]) {
1159
1160	if (verify_module_namespace(namespace, modname: mod->name))
1161	return 0;
1162
1163	for_each_modinfo_entry(imported_namespace, info, "import_ns") {
1164	if (strcmp(namespace, imported_namespace) == 0)
1165	return 0;
1166	}
1167	#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1168	pr_warn(
1169	#else
1170	pr_err(
1171	#endif
1172	"%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
1173	mod->name, kernel_symbol_name(sym), namespace);
1174	#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
1175	return -EINVAL;
1176	#endif
1177	}
1178	return 0;
1179	}
1180
1181	static bool inherit_taint(struct module *mod, struct module *owner, const char *name)
1182	{
1183	if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
1184	return true;
1185
1186	if (mod->using_gplonly_symbols) {
1187	pr_err("%s: module using GPL-only symbols uses symbols %s from proprietary module %s.\n",
1188	mod->name, name, owner->name);
1189	return false;
1190	}
1191
1192	if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
1193	pr_warn("%s: module uses symbols %s from proprietary module %s, inheriting taint.\n",
1194	mod->name, name, owner->name);
1195	set_bit(TAINT_PROPRIETARY_MODULE, addr: &mod->taints);
1196	}
1197	return true;
1198	}
1199
1200	/* Resolve a symbol for this module. I.e. if we find one, record usage. */
1201	static const struct kernel_symbol *resolve_symbol(struct module *mod,
1202	const struct load_info *info,
1203	const char *name,
1204	char ownername[])
1205	{
1206	struct find_symbol_arg fsa = {
1207	.name = name,
1208	.gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
1209	.warn = true,
1210	};
1211	int err;
1212
1213	/*
1214	* The module_mutex should not be a heavily contended lock;
1215	* if we get the occasional sleep here, we'll go an extra iteration
1216	* in the wait_event_interruptible(), which is harmless.
1217	*/
1218	sched_annotate_sleep();
1219	mutex_lock(&module_mutex);
1220	if (!find_symbol(fsa: &fsa))
1221	goto unlock;
1222
1223	if (fsa.license == GPL_ONLY)
1224	mod->using_gplonly_symbols = true;
1225
1226	if (!inherit_taint(mod, owner: fsa.owner, name)) {
1227	fsa.sym = NULL;
1228	goto getname;
1229	}
1230
1231	if (!check_version(info, symname: name, mod, crc: fsa.crc)) {
1232	fsa.sym = ERR_PTR(error: -EINVAL);
1233	goto getname;
1234	}
1235
1236	err = verify_namespace_is_imported(info, sym: fsa.sym, mod);
1237	if (err) {
1238	fsa.sym = ERR_PTR(error: err);
1239	goto getname;
1240	}
1241
1242	err = ref_module(a: mod, b: fsa.owner);
1243	if (err) {
1244	fsa.sym = ERR_PTR(error: err);
1245	goto getname;
1246	}
1247
1248	getname:
1249	/* We must make copy under the lock if we failed to get ref. */
1250	strscpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
1251	unlock:
1252	mutex_unlock(lock: &module_mutex);
1253	return fsa.sym;
1254	}
1255
1256	static const struct kernel_symbol *
1257	resolve_symbol_wait(struct module *mod,
1258	const struct load_info *info,
1259	const char *name)
1260	{
1261	const struct kernel_symbol *ksym;
1262	char owner[MODULE_NAME_LEN];
1263
1264	if (wait_event_interruptible_timeout(module_wq,
1265	!IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1266	|| PTR_ERR(ksym) != -EBUSY,
1267	30 * HZ) <= 0) {
1268	pr_warn("%s: gave up waiting for init of module %s.\n",
1269	mod->name, owner);
1270	}
1271	return ksym;
1272	}
1273
1274	void __weak module_arch_cleanup(struct module *mod)
1275	{
1276	}
1277
1278	void __weak module_arch_freeing_init(struct module *mod)
1279	{
1280	}
1281
1282	static int module_memory_alloc(struct module *mod, enum mod_mem_type type)
1283	{
1284	unsigned int size = PAGE_ALIGN(mod->mem[type].size);
1285	enum execmem_type execmem_type;
1286	void *ptr;
1287
1288	mod->mem[type].size = size;
1289
1290	if (mod_mem_type_is_data(type))
1291	execmem_type = EXECMEM_MODULE_DATA;
1292	else
1293	execmem_type = EXECMEM_MODULE_TEXT;
1294
1295	ptr = execmem_alloc(type: execmem_type, size);
1296	if (!ptr)
1297	return -ENOMEM;
1298
1299	if (execmem_is_rox(type: execmem_type)) {
1300	int err = execmem_make_temp_rw(ptr, size);
1301
1302	if (err) {
1303	execmem_free(ptr);
1304	return -ENOMEM;
1305	}
1306
1307	mod->mem[type].is_rox = true;
1308	}
1309
1310	/*
1311	* The pointer to these blocks of memory are stored on the module
1312	* structure and we keep that around so long as the module is
1313	* around. We only free that memory when we unload the module.
1314	* Just mark them as not being a leak then. The .init* ELF
1315	* sections *do* get freed after boot so we *could* treat them
1316	* slightly differently with kmemleak_ignore() and only grey
1317	* them out as they work as typical memory allocations which
1318	* *do* eventually get freed, but let's just keep things simple
1319	* and avoid *any* false positives.
1320	*/
1321	if (!mod->mem[type].is_rox)
1322	kmemleak_not_leak(ptr);
1323
1324	memset(ptr, 0, size);
1325	mod->mem[type].base = ptr;
1326
1327	return 0;
1328	}
1329
1330	static void module_memory_restore_rox(struct module *mod)
1331	{
1332	for_class_mod_mem_type(type, text) {
1333	struct module_memory *mem = &mod->mem[type];
1334
1335	if (mem->is_rox)
1336	execmem_restore_rox(ptr: mem->base, size: mem->size);
1337	}
1338	}
1339
1340	static void module_memory_free(struct module *mod, enum mod_mem_type type)
1341	{
1342	struct module_memory *mem = &mod->mem[type];
1343
1344	execmem_free(ptr: mem->base);
1345	}
1346
1347	static void free_mod_mem(struct module *mod)
1348	{
1349	for_each_mod_mem_type(type) {
1350	struct module_memory *mod_mem = &mod->mem[type];
1351
1352	if (type == MOD_DATA)
1353	continue;
1354
1355	/* Free lock-classes; relies on the preceding sync_rcu(). */
1356	lockdep_free_key_range(start: mod_mem->base, size: mod_mem->size);
1357	if (mod_mem->size)
1358	module_memory_free(mod, type);
1359	}
1360
1361	/* MOD_DATA hosts mod, so free it at last */
1362	lockdep_free_key_range(start: mod->mem[MOD_DATA].base, size: mod->mem[MOD_DATA].size);
1363	module_memory_free(mod, type: MOD_DATA);
1364	}
1365
1366	/* Free a module, remove from lists, etc. */
1367	static void free_module(struct module *mod)
1368	{
1369	trace_module_free(mod);
1370
1371	codetag_unload_module(mod);
1372
1373	mod_sysfs_teardown(mod);
1374
1375	/*
1376	* We leave it in list to prevent duplicate loads, but make sure
1377	* that noone uses it while it's being deconstructed.
1378	*/
1379	mutex_lock(&module_mutex);
1380	mod->state = MODULE_STATE_UNFORMED;
1381	mutex_unlock(lock: &module_mutex);
1382
1383	/* Arch-specific cleanup. */
1384	module_arch_cleanup(mod);
1385
1386	/* Module unload stuff */
1387	module_unload_free(mod);
1388
1389	/* Free any allocated parameters. */
1390	destroy_params(params: mod->kp, num: mod->num_kp);
1391
1392	if (is_livepatch_module(mod))
1393	free_module_elf(mod);
1394
1395	/* Now we can delete it from the lists */
1396	mutex_lock(&module_mutex);
1397	/* Unlink carefully: kallsyms could be walking list. */
1398	list_del_rcu(entry: &mod->list);
1399	mod_tree_remove(mod);
1400	/* Remove this module from bug list, this uses list_del_rcu */
1401	module_bug_cleanup(mod);
1402	/* Wait for RCU synchronizing before releasing mod->list and buglist. */
1403	synchronize_rcu();
1404	if (try_add_tainted_module(mod))
1405	pr_err("%s: adding tainted module to the unloaded tainted modules list failed.\n",
1406	mod->name);
1407	mutex_unlock(lock: &module_mutex);
1408
1409	/* This may be empty, but that's OK */
1410	module_arch_freeing_init(mod);
1411	kfree(objp: mod->args);
1412	percpu_modfree(mod);
1413
1414	free_mod_mem(mod);
1415	}
1416
1417	void *__symbol_get(const char *symbol)
1418	{
1419	struct find_symbol_arg fsa = {
1420	.name = symbol,
1421	.gplok = true,
1422	.warn = true,
1423	};
1424
1425	scoped_guard(rcu) {
1426	if (!find_symbol(fsa: &fsa))
1427	return NULL;
1428	if (fsa.license != GPL_ONLY) {
1429	pr_warn("failing symbol_get of non-GPLONLY symbol %s.\n",
1430	symbol);
1431	return NULL;
1432	}
1433	if (strong_try_module_get(mod: fsa.owner))
1434	return NULL;
1435	}
1436	return (void *)kernel_symbol_value(sym: fsa.sym);
1437	}
1438	EXPORT_SYMBOL_GPL(__symbol_get);
1439
1440	/*
1441	* Ensure that an exported symbol [global namespace] does not already exist
1442	* in the kernel or in some other module's exported symbol table.
1443	*
1444	* You must hold the module_mutex.
1445	*/
1446	static int verify_exported_symbols(struct module *mod)
1447	{
1448	unsigned int i;
1449	const struct kernel_symbol *s;
1450	struct {
1451	const struct kernel_symbol *sym;
1452	unsigned int num;
1453	} arr[] = {
1454	{ mod->syms, mod->num_syms },
1455	{ mod->gpl_syms, mod->num_gpl_syms },
1456	};
1457
1458	for (i = 0; i < ARRAY_SIZE(arr); i++) {
1459	for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1460	struct find_symbol_arg fsa = {
1461	.name = kernel_symbol_name(sym: s),
1462	.gplok = true,
1463	};
1464	if (find_symbol(fsa: &fsa)) {
1465	pr_err("%s: exports duplicate symbol %s"
1466	" (owned by %s)\n",
1467	mod->name, kernel_symbol_name(s),
1468	module_name(fsa.owner));
1469	return -ENOEXEC;
1470	}
1471	}
1472	}
1473	return 0;
1474	}
1475
1476	static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
1477	{
1478	/*
1479	* On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
1480	* before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
1481	* i386 has a similar problem but may not deserve a fix.
1482	*
1483	* If we ever have to ignore many symbols, consider refactoring the code to
1484	* only warn if referenced by a relocation.
1485	*/
1486	if (emachine == EM_386 || emachine == EM_X86_64)
1487	return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
1488	return false;
1489	}
1490
1491	/* Change all symbols so that st_value encodes the pointer directly. */
1492	static int simplify_symbols(struct module *mod, const struct load_info *info)
1493	{
1494	Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
1495	Elf_Sym *sym = (void *)symsec->sh_addr;
1496	unsigned long secbase;
1497	unsigned int i;
1498	int ret = 0;
1499	const struct kernel_symbol *ksym;
1500
1501	for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
1502	const char *name = info->strtab + sym[i].st_name;
1503
1504	switch (sym[i].st_shndx) {
1505	case SHN_COMMON:
1506	/* Ignore common symbols */
1507	if (!strncmp(name, "__gnu_lto", 9))
1508	break;
1509
1510	/*
1511	* We compiled with -fno-common. These are not
1512	* supposed to happen.
1513	*/
1514	pr_debug("Common symbol: %s\n", name);
1515	pr_warn("%s: please compile with -fno-common\n",
1516	mod->name);
1517	ret = -ENOEXEC;
1518	break;
1519
1520	case SHN_ABS:
1521	/* Don't need to do anything */
1522	pr_debug("Absolute symbol: 0x%08lx %s\n",
1523	(long)sym[i].st_value, name);
1524	break;
1525
1526	case SHN_LIVEPATCH:
1527	/* Livepatch symbols are resolved by livepatch */
1528	break;
1529
1530	case SHN_UNDEF:
1531	ksym = resolve_symbol_wait(mod, info, name);
1532	/* Ok if resolved. */
1533	if (ksym && !IS_ERR(ptr: ksym)) {
1534	sym[i].st_value = kernel_symbol_value(sym: ksym);
1535	break;
1536	}
1537
1538	/* Ok if weak or ignored. */
1539	if (!ksym &&
1540	(ELF_ST_BIND(sym[i].st_info) == STB_WEAK ||
1541	ignore_undef_symbol(emachine: info->hdr->e_machine, name)))
1542	break;
1543
1544	ret = PTR_ERR(ptr: ksym) ?: -ENOENT;
1545	pr_warn("%s: Unknown symbol %s (err %d)\n",
1546	mod->name, name, ret);
1547	break;
1548
1549	default:
1550	/* Divert to percpu allocation if a percpu var. */
1551	if (sym[i].st_shndx == info->index.pcpu)
1552	secbase = (unsigned long)mod_percpu(mod);
1553	else
1554	secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
1555	sym[i].st_value += secbase;
1556	break;
1557	}
1558	}
1559
1560	return ret;
1561	}
1562
1563	static int apply_relocations(struct module *mod, const struct load_info *info)
1564	{
1565	unsigned int i;
1566	int err = 0;
1567
1568	/* Now do relocations. */
1569	for (i = 1; i < info->hdr->e_shnum; i++) {
1570	unsigned int infosec = info->sechdrs[i].sh_info;
1571
1572	/* Not a valid relocation section? */
1573	if (infosec >= info->hdr->e_shnum)
1574	continue;
1575
1576	/* Don't bother with non-allocated sections */
1577	if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
1578	continue;
1579
1580	if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
1581	err = klp_apply_section_relocs(pmod: mod, sechdrs: info->sechdrs,
1582	shstrtab: info->secstrings,
1583	strtab: info->strtab,
1584	symindex: info->index.sym, secindex: i,
1585	NULL);
1586	else if (info->sechdrs[i].sh_type == SHT_REL)
1587	err = apply_relocate(sechdrs: info->sechdrs, strtab: info->strtab,
1588	symindex: info->index.sym, relsec: i, me: mod);
1589	else if (info->sechdrs[i].sh_type == SHT_RELA)
1590	err = apply_relocate_add(sechdrs: info->sechdrs, strtab: info->strtab,
1591	symindex: info->index.sym, relsec: i, mod);
1592	if (err < 0)
1593	break;
1594	}
1595	return err;
1596	}
1597
1598	/* Additional bytes needed by arch in front of individual sections */
1599	unsigned int __weak arch_mod_section_prepend(struct module *mod,
1600	unsigned int section)
1601	{
1602	/* default implementation just returns zero */
1603	return 0;
1604	}
1605
1606	long module_get_offset_and_type(struct module *mod, enum mod_mem_type type,
1607	Elf_Shdr *sechdr, unsigned int section)
1608	{
1609	long offset;
1610	long mask = ((unsigned long)(type) & SH_ENTSIZE_TYPE_MASK) << SH_ENTSIZE_TYPE_SHIFT;
1611
1612	mod->mem[type].size += arch_mod_section_prepend(mod, section);
1613	offset = ALIGN(mod->mem[type].size, sechdr->sh_addralign ?: 1);
1614	mod->mem[type].size = offset + sechdr->sh_size;
1615
1616	WARN_ON_ONCE(offset & mask);
1617	return offset | mask;
1618	}
1619
1620	bool module_init_layout_section(const char *sname)
1621	{
1622	#ifndef CONFIG_MODULE_UNLOAD
1623	if (module_exit_section(sname))
1624	return true;
1625	#endif
1626	return module_init_section(name: sname);
1627	}
1628
1629	static void __layout_sections(struct module *mod, struct load_info *info, bool is_init)
1630	{
1631	unsigned int m, i;
1632
1633	/*
1634	* { Mask of required section header flags,
1635	* Mask of excluded section header flags }
1636	*/
1637	static const unsigned long masks[][2] = {
1638	{ SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
1639	{ SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
1640	{ SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL },
1641	{ SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
1642	{ ARCH_SHF_SMALL | SHF_ALLOC, 0 }
1643	};
1644	static const int core_m_to_mem_type[] = {
1645	MOD_TEXT,
1646	MOD_RODATA,
1647	MOD_RO_AFTER_INIT,
1648	MOD_DATA,
1649	MOD_DATA,
1650	};
1651	static const int init_m_to_mem_type[] = {
1652	MOD_INIT_TEXT,
1653	MOD_INIT_RODATA,
1654	MOD_INVALID,
1655	MOD_INIT_DATA,
1656	MOD_INIT_DATA,
1657	};
1658
1659	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
1660	enum mod_mem_type type = is_init ? init_m_to_mem_type[m] : core_m_to_mem_type[m];
1661
1662	for (i = 0; i < info->hdr->e_shnum; ++i) {
1663	Elf_Shdr *s = &info->sechdrs[i];
1664	const char *sname = info->secstrings + s->sh_name;
1665
1666	if ((s->sh_flags & masks[m][0]) != masks[m][0]
1667	|| (s->sh_flags & masks[m][1])
1668	|| s->sh_entsize != ~0UL
1669	|| is_init != module_init_layout_section(sname))
1670	continue;
1671
1672	if (WARN_ON_ONCE(type == MOD_INVALID))
1673	continue;
1674
1675	/*
1676	* Do not allocate codetag memory as we load it into
1677	* preallocated contiguous memory.
1678	*/
1679	if (codetag_needs_module_section(mod, name: sname, size: s->sh_size)) {
1680	/*
1681	* s->sh_entsize won't be used but populate the
1682	* type field to avoid confusion.
1683	*/
1684	s->sh_entsize = ((unsigned long)(type) & SH_ENTSIZE_TYPE_MASK)
1685	<< SH_ENTSIZE_TYPE_SHIFT;
1686	continue;
1687	}
1688
1689	s->sh_entsize = module_get_offset_and_type(mod, type, sechdr: s, section: i);
1690	pr_debug("\t%s\n", sname);
1691	}
1692	}
1693	}
1694
1695	/*
1696	* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
1697	* might -- code, read-only data, read-write data, small data. Tally
1698	* sizes, and place the offsets into sh_entsize fields: high bit means it
1699	* belongs in init.
1700	*/
1701	static void layout_sections(struct module *mod, struct load_info *info)
1702	{
1703	unsigned int i;
1704
1705	for (i = 0; i < info->hdr->e_shnum; i++)
1706	info->sechdrs[i].sh_entsize = ~0UL;
1707
1708	pr_debug("Core section allocation order for %s:\n", mod->name);
1709	__layout_sections(mod, info, is_init: false);
1710
1711	pr_debug("Init section allocation order for %s:\n", mod->name);
1712	__layout_sections(mod, info, is_init: true);
1713	}
1714
1715	static void module_license_taint_check(struct module *mod, const char *license)
1716	{
1717	if (!license)
1718	license = "unspecified";
1719
1720	if (!license_is_gpl_compatible(license)) {
1721	if (!test_taint(TAINT_PROPRIETARY_MODULE))
1722	pr_warn("%s: module license '%s' taints kernel.\n",
1723	mod->name, license);
1724	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
1725	lockdep_ok: LOCKDEP_NOW_UNRELIABLE);
1726	}
1727	}
1728
1729	static int setup_modinfo(struct module *mod, struct load_info *info)
1730	{
1731	const struct module_attribute *attr;
1732	char *imported_namespace;
1733	int i;
1734
1735	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1736	if (attr->setup)
1737	attr->setup(mod, get_modinfo(info, tag: attr->attr.name));
1738	}
1739
1740	for_each_modinfo_entry(imported_namespace, info, "import_ns") {
1741	/*
1742	* 'module:' prefixed namespaces are implicit, disallow
1743	* explicit imports.
1744	*/
1745	if (strstarts(str: imported_namespace, prefix: "module:")) {
1746	pr_err("%s: module tries to import module namespace: %s\n",
1747	mod->name, imported_namespace);
1748	return -EPERM;
1749	}
1750	}
1751
1752	return 0;
1753	}
1754
1755	static void free_modinfo(struct module *mod)
1756	{
1757	const struct module_attribute *attr;
1758	int i;
1759
1760	for (i = 0; (attr = modinfo_attrs[i]); i++) {
1761	if (attr->free)
1762	attr->free(mod);
1763	}
1764	}
1765
1766	bool __weak module_init_section(const char *name)
1767	{
1768	return strstarts(str: name, prefix: ".init");
1769	}
1770
1771	bool __weak module_exit_section(const char *name)
1772	{
1773	return strstarts(str: name, prefix: ".exit");
1774	}
1775
1776	static int validate_section_offset(const struct load_info *info, Elf_Shdr *shdr)
1777	{
1778	#if defined(CONFIG_64BIT)
1779	unsigned long long secend;
1780	#else
1781	unsigned long secend;
1782	#endif
1783
1784	/*
1785	* Check for both overflow and offset/size being
1786	* too large.
1787	*/
1788	secend = shdr->sh_offset + shdr->sh_size;
1789	if (secend < shdr->sh_offset || secend > info->len)
1790	return -ENOEXEC;
1791
1792	return 0;
1793	}
1794
1795	/**
1796	* elf_validity_ehdr() - Checks an ELF header for module validity
1797	* @info: Load info containing the ELF header to check
1798	*
1799	* Checks whether an ELF header could belong to a valid module. Checks:
1800	*
1801	* * ELF header is within the data the user provided
1802	* * ELF magic is present
1803	* * It is relocatable (not final linked, not core file, etc.)
1804	* * The header's machine type matches what the architecture expects.
1805	* * Optional arch-specific hook for other properties
1806	* - module_elf_check_arch() is currently only used by PPC to check
1807	* ELF ABI version, but may be used by others in the future.
1808	*
1809	* Return: %0 if valid, %-ENOEXEC on failure.
1810	*/
1811	static int elf_validity_ehdr(const struct load_info *info)
1812	{
1813	if (info->len < sizeof(*(info->hdr))) {
1814	pr_err("Invalid ELF header len %lu\n", info->len);
1815	return -ENOEXEC;
1816	}
1817	if (memcmp(p: info->hdr->e_ident, ELFMAG, SELFMAG) != 0) {
1818	pr_err("Invalid ELF header magic: != %s\n", ELFMAG);
1819	return -ENOEXEC;
1820	}
1821	if (info->hdr->e_type != ET_REL) {
1822	pr_err("Invalid ELF header type: %u != %u\n",
1823	info->hdr->e_type, ET_REL);
1824	return -ENOEXEC;
1825	}
1826	if (!elf_check_arch(info->hdr)) {
1827	pr_err("Invalid architecture in ELF header: %u\n",
1828	info->hdr->e_machine);
1829	return -ENOEXEC;
1830	}
1831	if (!module_elf_check_arch(hdr: info->hdr)) {
1832	pr_err("Invalid module architecture in ELF header: %u\n",
1833	info->hdr->e_machine);
1834	return -ENOEXEC;
1835	}
1836	return 0;
1837	}
1838
1839	/**
1840	* elf_validity_cache_sechdrs() - Cache section headers if valid
1841	* @info: Load info to compute section headers from
1842	*
1843	* Checks:
1844	*
1845	* * ELF header is valid (see elf_validity_ehdr())
1846	* * Section headers are the size we expect
1847	* * Section array fits in the user provided data
1848	* * Section index 0 is NULL
1849	* * Section contents are inbounds
1850	*
1851	* Then updates @info with a &load_info->sechdrs pointer if valid.
1852	*
1853	* Return: %0 if valid, negative error code if validation failed.
1854	*/
1855	static int elf_validity_cache_sechdrs(struct load_info *info)
1856	{
1857	Elf_Shdr *sechdrs;
1858	Elf_Shdr *shdr;
1859	int i;
1860	int err;
1861
1862	err = elf_validity_ehdr(info);
1863	if (err < 0)
1864	return err;
1865
1866	if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) {
1867	pr_err("Invalid ELF section header size\n");
1868	return -ENOEXEC;
1869	}
1870
1871	/*
1872	* e_shnum is 16 bits, and sizeof(Elf_Shdr) is
1873	* known and small. So e_shnum * sizeof(Elf_Shdr)
1874	* will not overflow unsigned long on any platform.
1875	*/
1876	if (info->hdr->e_shoff >= info->len
1877	|| (info->hdr->e_shnum * sizeof(Elf_Shdr) >
1878	info->len - info->hdr->e_shoff)) {
1879	pr_err("Invalid ELF section header overflow\n");
1880	return -ENOEXEC;
1881	}
1882
1883	sechdrs = (void *)info->hdr + info->hdr->e_shoff;
1884
1885	/*
1886	* The code assumes that section 0 has a length of zero and
1887	* an addr of zero, so check for it.
1888	*/
1889	if (sechdrs[0].sh_type != SHT_NULL
1890	|| sechdrs[0].sh_size != 0
1891	|| sechdrs[0].sh_addr != 0) {
1892	pr_err("ELF Spec violation: section 0 type(%d)!=SH_NULL or non-zero len or addr\n",
1893	sechdrs[0].sh_type);
1894	return -ENOEXEC;
1895	}
1896
1897	/* Validate contents are inbounds */
1898	for (i = 1; i < info->hdr->e_shnum; i++) {
1899	shdr = &sechdrs[i];
1900	switch (shdr->sh_type) {
1901	case SHT_NULL:
1902	case SHT_NOBITS:
1903	/* No contents, offset/size don't mean anything */
1904	continue;
1905	default:
1906	err = validate_section_offset(info, shdr);
1907	if (err < 0) {
1908	pr_err("Invalid ELF section in module (section %u type %u)\n",
1909	i, shdr->sh_type);
1910	return err;
1911	}
1912	}
1913	}
1914
1915	info->sechdrs = sechdrs;
1916
1917	return 0;
1918	}
1919
1920	/**
1921	* elf_validity_cache_secstrings() - Caches section names if valid
1922	* @info: Load info to cache section names from. Must have valid sechdrs.
1923	*
1924	* Specifically checks:
1925	*
1926	* * Section name table index is inbounds of section headers
1927	* * Section name table is not empty
1928	* * Section name table is NUL terminated
1929	* * All section name offsets are inbounds of the section
1930	*
1931	* Then updates @info with a &load_info->secstrings pointer if valid.
1932	*
1933	* Return: %0 if valid, negative error code if validation failed.
1934	*/
1935	static int elf_validity_cache_secstrings(struct load_info *info)
1936	{
1937	Elf_Shdr *strhdr, *shdr;
1938	char *secstrings;
1939	int i;
1940
1941	/*
1942	* Verify if the section name table index is valid.
1943	*/
1944	if (info->hdr->e_shstrndx == SHN_UNDEF
1945	|| info->hdr->e_shstrndx >= info->hdr->e_shnum) {
1946	pr_err("Invalid ELF section name index: %d || e_shstrndx (%d) >= e_shnum (%d)\n",
1947	info->hdr->e_shstrndx, info->hdr->e_shstrndx,
1948	info->hdr->e_shnum);
1949	return -ENOEXEC;
1950	}
1951
1952	strhdr = &info->sechdrs[info->hdr->e_shstrndx];
1953
1954	/*
1955	* The section name table must be NUL-terminated, as required
1956	* by the spec. This makes strcmp and pr_* calls that access
1957	* strings in the section safe.
1958	*/
1959	secstrings = (void *)info->hdr + strhdr->sh_offset;
1960	if (strhdr->sh_size == 0) {
1961	pr_err("empty section name table\n");
1962	return -ENOEXEC;
1963	}
1964	if (secstrings[strhdr->sh_size - 1] != '\0') {
1965	pr_err("ELF Spec violation: section name table isn't null terminated\n");
1966	return -ENOEXEC;
1967	}
1968
1969	for (i = 0; i < info->hdr->e_shnum; i++) {
1970	shdr = &info->sechdrs[i];
1971	/* SHT_NULL means sh_name has an undefined value */
1972	if (shdr->sh_type == SHT_NULL)
1973	continue;
1974	if (shdr->sh_name >= strhdr->sh_size) {
1975	pr_err("Invalid ELF section name in module (section %u type %u)\n",
1976	i, shdr->sh_type);
1977	return -ENOEXEC;
1978	}
1979	}
1980
1981	info->secstrings = secstrings;
1982	return 0;
1983	}
1984
1985	/**
1986	* elf_validity_cache_index_info() - Validate and cache modinfo section
1987	* @info: Load info to populate the modinfo index on.
1988	* Must have &load_info->sechdrs and &load_info->secstrings populated
1989	*
1990	* Checks that if there is a .modinfo section, it is unique.
1991	* Then, it caches its index in &load_info->index.info.
1992	* Finally, it tries to populate the name to improve error messages.
1993	*
1994	* Return: %0 if valid, %-ENOEXEC if multiple modinfo sections were found.
1995	*/
1996	static int elf_validity_cache_index_info(struct load_info *info)
1997	{
1998	int info_idx;
1999
2000	info_idx = find_any_unique_sec(info, name: ".modinfo");
2001
2002	if (info_idx == 0)
2003	/* Early return, no .modinfo */
2004	return 0;
2005
2006	if (info_idx < 0) {
2007	pr_err("Only one .modinfo section must exist.\n");
2008	return -ENOEXEC;
2009	}
2010
2011	info->index.info = info_idx;
2012	/* Try to find a name early so we can log errors with a module name */
2013	info->name = get_modinfo(info, tag: "name");
2014
2015	return 0;
2016	}
2017
2018	/**
2019	* elf_validity_cache_index_mod() - Validates and caches this_module section
2020	* @info: Load info to cache this_module on.
2021	* Must have &load_info->sechdrs and &load_info->secstrings populated
2022	*
2023	* The ".gnu.linkonce.this_module" ELF section is special. It is what modpost
2024	* uses to refer to __this_module and let's use rely on THIS_MODULE to point
2025	* to &__this_module properly. The kernel's modpost declares it on each
2026	* modules's *.mod.c file. If the struct module of the kernel changes a full
2027	* kernel rebuild is required.
2028	*
2029	* We have a few expectations for this special section, this function
2030	* validates all this for us:
2031	*
2032	* * The section has contents
2033	* * The section is unique
2034	* * We expect the kernel to always have to allocate it: SHF_ALLOC
2035	* * The section size must match the kernel's run time's struct module
2036	* size
2037	*
2038	* If all checks pass, the index will be cached in &load_info->index.mod
2039	*
2040	* Return: %0 on validation success, %-ENOEXEC on failure
2041	*/
2042	static int elf_validity_cache_index_mod(struct load_info *info)
2043	{
2044	Elf_Shdr *shdr;
2045	int mod_idx;
2046
2047	mod_idx = find_any_unique_sec(info, name: ".gnu.linkonce.this_module");
2048	if (mod_idx <= 0) {
2049	pr_err("module %s: Exactly one .gnu.linkonce.this_module section must exist.\n",
2050	info->name ?: "(missing .modinfo section or name field)");
2051	return -ENOEXEC;
2052	}
2053
2054	shdr = &info->sechdrs[mod_idx];
2055
2056	if (shdr->sh_type == SHT_NOBITS) {
2057	pr_err("module %s: .gnu.linkonce.this_module section must have a size set\n",
2058	info->name ?: "(missing .modinfo section or name field)");
2059	return -ENOEXEC;
2060	}
2061
2062	if (!(shdr->sh_flags & SHF_ALLOC)) {
2063	pr_err("module %s: .gnu.linkonce.this_module must occupy memory during process execution\n",
2064	info->name ?: "(missing .modinfo section or name field)");
2065	return -ENOEXEC;
2066	}
2067
2068	if (shdr->sh_size != sizeof(struct module)) {
2069	pr_err("module %s: .gnu.linkonce.this_module section size must match the kernel's built struct module size at run time\n",
2070	info->name ?: "(missing .modinfo section or name field)");
2071	return -ENOEXEC;
2072	}
2073
2074	info->index.mod = mod_idx;
2075
2076	return 0;
2077	}
2078
2079	/**
2080	* elf_validity_cache_index_sym() - Validate and cache symtab index
2081	* @info: Load info to cache symtab index in.
2082	* Must have &load_info->sechdrs and &load_info->secstrings populated.
2083	*
2084	* Checks that there is exactly one symbol table, then caches its index in
2085	* &load_info->index.sym.
2086	*
2087	* Return: %0 if valid, %-ENOEXEC on failure.
2088	*/
2089	static int elf_validity_cache_index_sym(struct load_info *info)
2090	{
2091	unsigned int sym_idx;
2092	unsigned int num_sym_secs = 0;
2093	int i;
2094
2095	for (i = 1; i < info->hdr->e_shnum; i++) {
2096	if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2097	num_sym_secs++;
2098	sym_idx = i;
2099	}
2100	}
2101
2102	if (num_sym_secs != 1) {
2103	pr_warn("%s: module has no symbols (stripped?)\n",
2104	info->name ?: "(missing .modinfo section or name field)");
2105	return -ENOEXEC;
2106	}
2107
2108	info->index.sym = sym_idx;
2109
2110	return 0;
2111	}
2112
2113	/**
2114	* elf_validity_cache_index_str() - Validate and cache strtab index
2115	* @info: Load info to cache strtab index in.
2116	* Must have &load_info->sechdrs and &load_info->secstrings populated.
2117	* Must have &load_info->index.sym populated.
2118	*
2119	* Looks at the symbol table's associated string table, makes sure it is
2120	* in-bounds, and caches it.
2121	*
2122	* Return: %0 if valid, %-ENOEXEC on failure.
2123	*/
2124	static int elf_validity_cache_index_str(struct load_info *info)
2125	{
2126	unsigned int str_idx = info->sechdrs[info->index.sym].sh_link;
2127
2128	if (str_idx == SHN_UNDEF || str_idx >= info->hdr->e_shnum) {
2129	pr_err("Invalid ELF sh_link!=SHN_UNDEF(%d) or (sh_link(%d) >= hdr->e_shnum(%d)\n",
2130	str_idx, str_idx, info->hdr->e_shnum);
2131	return -ENOEXEC;
2132	}
2133
2134	info->index.str = str_idx;
2135	return 0;
2136	}
2137
2138	/**
2139	* elf_validity_cache_index_versions() - Validate and cache version indices
2140	* @info: Load info to cache version indices in.
2141	* Must have &load_info->sechdrs and &load_info->secstrings populated.
2142	* @flags: Load flags, relevant to suppress version loading, see
2143	* uapi/linux/module.h
2144	*
2145	* If we're ignoring modversions based on @flags, zero all version indices
2146	* and return validity. Othewrise check:
2147	*
2148	* * If "__version_ext_crcs" is present, "__version_ext_names" is present
2149	* * There is a name present for every crc
2150	*
2151	* Then populate:
2152	*
2153	* * &load_info->index.vers
2154	* * &load_info->index.vers_ext_crc
2155	* * &load_info->index.vers_ext_names
2156	*
2157	* if present.
2158	*
2159	* Return: %0 if valid, %-ENOEXEC on failure.
2160	*/
2161	static int elf_validity_cache_index_versions(struct load_info *info, int flags)
2162	{
2163	unsigned int vers_ext_crc;
2164	unsigned int vers_ext_name;
2165	size_t crc_count;
2166	size_t remaining_len;
2167	size_t name_size;
2168	char *name;
2169
2170	/* If modversions were suppressed, pretend we didn't find any */
2171	if (flags & MODULE_INIT_IGNORE_MODVERSIONS) {
2172	info->index.vers = 0;
2173	info->index.vers_ext_crc = 0;
2174	info->index.vers_ext_name = 0;
2175	return 0;
2176	}
2177
2178	vers_ext_crc = find_sec(info, name: "__version_ext_crcs");
2179	vers_ext_name = find_sec(info, name: "__version_ext_names");
2180
2181	/* If we have one field, we must have the other */
2182	if (!!vers_ext_crc != !!vers_ext_name) {
2183	pr_err("extended version crc+name presence does not match");
2184	return -ENOEXEC;
2185	}
2186
2187	/*
2188	* If we have extended version information, we should have the same
2189	* number of entries in every section.
2190	*/
2191	if (vers_ext_crc) {
2192	crc_count = info->sechdrs[vers_ext_crc].sh_size / sizeof(u32);
2193	name = (void *)info->hdr +
2194	info->sechdrs[vers_ext_name].sh_offset;
2195	remaining_len = info->sechdrs[vers_ext_name].sh_size;
2196
2197	while (crc_count--) {
2198	name_size = strnlen(p: name, maxlen: remaining_len) + 1;
2199	if (name_size > remaining_len) {
2200	pr_err("more extended version crcs than names");
2201	return -ENOEXEC;
2202	}
2203	remaining_len -= name_size;
2204	name += name_size;
2205	}
2206	}
2207
2208	info->index.vers = find_sec(info, name: "__versions");
2209	info->index.vers_ext_crc = vers_ext_crc;
2210	info->index.vers_ext_name = vers_ext_name;
2211	return 0;
2212	}
2213
2214	/**
2215	* elf_validity_cache_index() - Resolve, validate, cache section indices
2216	* @info: Load info to read from and update.
2217	* &load_info->sechdrs and &load_info->secstrings must be populated.
2218	* @flags: Load flags, relevant to suppress version loading, see
2219	* uapi/linux/module.h
2220	*
2221	* Populates &load_info->index, validating as it goes.
2222	* See child functions for per-field validation:
2223	*
2224	* * elf_validity_cache_index_info()
2225	* * elf_validity_cache_index_mod()
2226	* * elf_validity_cache_index_sym()
2227	* * elf_validity_cache_index_str()
2228	* * elf_validity_cache_index_versions()
2229	*
2230	* If CONFIG_SMP is enabled, load the percpu section by name with no
2231	* validation.
2232	*
2233	* Return: 0 on success, negative error code if an index failed validation.
2234	*/
2235	static int elf_validity_cache_index(struct load_info *info, int flags)
2236	{
2237	int err;
2238
2239	err = elf_validity_cache_index_info(info);
2240	if (err < 0)
2241	return err;
2242	err = elf_validity_cache_index_mod(info);
2243	if (err < 0)
2244	return err;
2245	err = elf_validity_cache_index_sym(info);
2246	if (err < 0)
2247	return err;
2248	err = elf_validity_cache_index_str(info);
2249	if (err < 0)
2250	return err;
2251	err = elf_validity_cache_index_versions(info, flags);
2252	if (err < 0)
2253	return err;
2254
2255	info->index.pcpu = find_pcpusec(info);
2256
2257	return 0;
2258	}
2259
2260	/**
2261	* elf_validity_cache_strtab() - Validate and cache symbol string table
2262	* @info: Load info to read from and update.
2263	* Must have &load_info->sechdrs and &load_info->secstrings populated.
2264	* Must have &load_info->index populated.
2265	*
2266	* Checks:
2267	*
2268	* * The string table is not empty.
2269	* * The string table starts and ends with NUL (required by ELF spec).
2270	* * Every &Elf_Sym->st_name offset in the symbol table is inbounds of the
2271	* string table.
2272	*
2273	* And caches the pointer as &load_info->strtab in @info.
2274	*
2275	* Return: 0 on success, negative error code if a check failed.
2276	*/
2277	static int elf_validity_cache_strtab(struct load_info *info)
2278	{
2279	Elf_Shdr *str_shdr = &info->sechdrs[info->index.str];
2280	Elf_Shdr *sym_shdr = &info->sechdrs[info->index.sym];
2281	char *strtab = (char *)info->hdr + str_shdr->sh_offset;
2282	Elf_Sym *syms = (void *)info->hdr + sym_shdr->sh_offset;
2283	int i;
2284
2285	if (str_shdr->sh_size == 0) {
2286	pr_err("empty symbol string table\n");
2287	return -ENOEXEC;
2288	}
2289	if (strtab[0] != '\0') {
2290	pr_err("symbol string table missing leading NUL\n");
2291	return -ENOEXEC;
2292	}
2293	if (strtab[str_shdr->sh_size - 1] != '\0') {
2294	pr_err("symbol string table isn't NUL terminated\n");
2295	return -ENOEXEC;
2296	}
2297
2298	/*
2299	* Now that we know strtab is correctly structured, check symbol
2300	* starts are inbounds before they're used later.
2301	*/
2302	for (i = 0; i < sym_shdr->sh_size / sizeof(*syms); i++) {
2303	if (syms[i].st_name >= str_shdr->sh_size) {
2304	pr_err("symbol name out of bounds in string table");
2305	return -ENOEXEC;
2306	}
2307	}
2308
2309	info->strtab = strtab;
2310	return 0;
2311	}
2312
2313	/*
2314	* Check userspace passed ELF module against our expectations, and cache
2315	* useful variables for further processing as we go.
2316	*
2317	* This does basic validity checks against section offsets and sizes, the
2318	* section name string table, and the indices used for it (sh_name).
2319	*
2320	* As a last step, since we're already checking the ELF sections we cache
2321	* useful variables which will be used later for our convenience:
2322	*
2323	* o pointers to section headers
2324	* o cache the modinfo symbol section
2325	* o cache the string symbol section
2326	* o cache the module section
2327	*
2328	* As a last step we set info->mod to the temporary copy of the module in
2329	* info->hdr. The final one will be allocated in move_module(). Any
2330	* modifications we make to our copy of the module will be carried over
2331	* to the final minted module.
2332	*/
2333	static int elf_validity_cache_copy(struct load_info *info, int flags)
2334	{
2335	int err;
2336
2337	err = elf_validity_cache_sechdrs(info);
2338	if (err < 0)
2339	return err;
2340	err = elf_validity_cache_secstrings(info);
2341	if (err < 0)
2342	return err;
2343	err = elf_validity_cache_index(info, flags);
2344	if (err < 0)
2345	return err;
2346	err = elf_validity_cache_strtab(info);
2347	if (err < 0)
2348	return err;
2349
2350	/* This is temporary: point mod into copy of data. */
2351	info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;
2352
2353	/*
2354	* If we didn't load the .modinfo 'name' field earlier, fall back to
2355	* on-disk struct mod 'name' field.
2356	*/
2357	if (!info->name)
2358	info->name = info->mod->name;
2359
2360	return 0;
2361	}
2362
2363	#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2364
2365	static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2366	{
2367	do {
2368	unsigned long n = min(len, COPY_CHUNK_SIZE);
2369
2370	if (copy_from_user(to: dst, from: usrc, n) != 0)
2371	return -EFAULT;
2372	cond_resched();
2373	dst += n;
2374	usrc += n;
2375	len -= n;
2376	} while (len);
2377	return 0;
2378	}
2379
2380	static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
2381	{
2382	if (!get_modinfo(info, tag: "livepatch"))
2383	/* Nothing more to do */
2384	return 0;
2385
2386	if (set_livepatch_module(mod))
2387	return 0;
2388
2389	pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2390	mod->name);
2391	return -ENOEXEC;
2392	}
2393
2394	static void check_modinfo_retpoline(struct module *mod, struct load_info *info)
2395	{
2396	if (retpoline_module_ok(has_retpoline: get_modinfo(info, tag: "retpoline")))
2397	return;
2398
2399	pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2400	mod->name);
2401	}
2402
2403	/* Sets info->hdr and info->len. */
2404	static int copy_module_from_user(const void __user *umod, unsigned long len,
2405	struct load_info *info)
2406	{
2407	int err;
2408
2409	info->len = len;
2410	if (info->len < sizeof(*(info->hdr)))
2411	return -ENOEXEC;
2412
2413	err = security_kernel_load_data(id: LOADING_MODULE, contents: true);
2414	if (err)
2415	return err;
2416
2417	/* Suck in entire file: we'll want most of it. */
2418	info->hdr = __vmalloc(info->len, GFP_KERNEL | __GFP_NOWARN);
2419	if (!info->hdr)
2420	return -ENOMEM;
2421
2422	if (copy_chunked_from_user(dst: info->hdr, usrc: umod, len: info->len) != 0) {
2423	err = -EFAULT;
2424	goto out;
2425	}
2426
2427	err = security_kernel_post_load_data(buf: (char *)info->hdr, size: info->len,
2428	id: LOADING_MODULE, description: "init_module");
2429	out:
2430	if (err)
2431	vfree(addr: info->hdr);
2432
2433	return err;
2434	}
2435
2436	static void free_copy(struct load_info *info, int flags)
2437	{
2438	if (flags & MODULE_INIT_COMPRESSED_FILE)
2439	module_decompress_cleanup(info);
2440	else
2441	vfree(addr: info->hdr);
2442	}
2443
2444	static int rewrite_section_headers(struct load_info *info, int flags)
2445	{
2446	unsigned int i;
2447
2448	/* This should always be true, but let's be sure. */
2449	info->sechdrs[0].sh_addr = 0;
2450
2451	for (i = 1; i < info->hdr->e_shnum; i++) {
2452	Elf_Shdr *shdr = &info->sechdrs[i];
2453
2454	/*
2455	* Mark all sections sh_addr with their address in the
2456	* temporary image.
2457	*/
2458	shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2459
2460	}
2461
2462	/* Track but don't keep modinfo and version sections. */
2463	info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
2464	info->sechdrs[info->index.vers_ext_crc].sh_flags &=
2465	~(unsigned long)SHF_ALLOC;
2466	info->sechdrs[info->index.vers_ext_name].sh_flags &=
2467	~(unsigned long)SHF_ALLOC;
2468	info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2469
2470	return 0;
2471	}
2472
2473	static const char *const module_license_offenders[] = {
2474	/* driverloader was caught wrongly pretending to be under GPL */
2475	"driverloader",
2476
2477	/* lve claims to be GPL but upstream won't provide source */
2478	"lve",
2479	};
2480
2481	/*
2482	* These calls taint the kernel depending certain module circumstances */
2483	static void module_augment_kernel_taints(struct module *mod, struct load_info *info)
2484	{
2485	int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
2486	size_t i;
2487
2488	if (!get_modinfo(info, tag: "intree")) {
2489	if (!test_taint(TAINT_OOT_MODULE))
2490	pr_warn("%s: loading out-of-tree module taints kernel.\n",
2491	mod->name);
2492	add_taint_module(mod, TAINT_OOT_MODULE, lockdep_ok: LOCKDEP_STILL_OK);
2493	}
2494
2495	check_modinfo_retpoline(mod, info);
2496
2497	if (get_modinfo(info, tag: "staging")) {
2498	add_taint_module(mod, TAINT_CRAP, lockdep_ok: LOCKDEP_STILL_OK);
2499	pr_warn("%s: module is from the staging directory, the quality "
2500	"is unknown, you have been warned.\n", mod->name);
2501	}
2502
2503	if (is_livepatch_module(mod)) {
2504	add_taint_module(mod, TAINT_LIVEPATCH, lockdep_ok: LOCKDEP_STILL_OK);
2505	pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2506	mod->name);
2507	}
2508
2509	module_license_taint_check(mod, license: get_modinfo(info, tag: "license"));
2510
2511	if (get_modinfo(info, tag: "test")) {
2512	if (!test_taint(TAINT_TEST))
2513	pr_warn("%s: loading test module taints kernel.\n",
2514	mod->name);
2515	add_taint_module(mod, TAINT_TEST, lockdep_ok: LOCKDEP_STILL_OK);
2516	}
2517	#ifdef CONFIG_MODULE_SIG
2518	mod->sig_ok = info->sig_ok;
2519	if (!mod->sig_ok) {
2520	pr_notice_once("%s: module verification failed: signature "
2521	"and/or required key missing - tainting "
2522	"kernel\n", mod->name);
2523	add_taint_module(mod, TAINT_UNSIGNED_MODULE, lockdep_ok: LOCKDEP_STILL_OK);
2524	}
2525	#endif
2526
2527	/*
2528	* ndiswrapper is under GPL by itself, but loads proprietary modules.
2529	* Don't use add_taint_module(), as it would prevent ndiswrapper from
2530	* using GPL-only symbols it needs.
2531	*/
2532	if (strcmp(mod->name, "ndiswrapper") == 0)
2533	add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
2534
2535	for (i = 0; i < ARRAY_SIZE(module_license_offenders); ++i) {
2536	if (strcmp(mod->name, module_license_offenders[i]) == 0)
2537	add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2538	lockdep_ok: LOCKDEP_NOW_UNRELIABLE);
2539	}
2540
2541	if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
2542	pr_warn("%s: module license taints kernel.\n", mod->name);
2543
2544	}
2545
2546	static int check_modinfo(struct module *mod, struct load_info *info, int flags)
2547	{
2548	const char *modmagic = get_modinfo(info, tag: "vermagic");
2549	int err;
2550
2551	if (flags & MODULE_INIT_IGNORE_VERMAGIC)
2552	modmagic = NULL;
2553
2554	/* This is allowed: modprobe --force will invalidate it. */
2555	if (!modmagic) {
2556	err = try_to_force_load(mod, reason: "bad vermagic");
2557	if (err)
2558	return err;
2559	} else if (!same_magic(amagic: modmagic, bmagic: vermagic, has_crcs: info->index.vers)) {
2560	pr_err("%s: version magic '%s' should be '%s'\n",
2561	info->name, modmagic, vermagic);
2562	return -ENOEXEC;
2563	}
2564
2565	err = check_modinfo_livepatch(mod, info);
2566	if (err)
2567	return err;
2568
2569	return 0;
2570	}
2571
2572	static int find_module_sections(struct module *mod, struct load_info *info)
2573	{
2574	mod->kp = section_objs(info, name: "__param",
2575	object_size: sizeof(*mod->kp), num: &mod->num_kp);
2576	mod->syms = section_objs(info, name: "__ksymtab",
2577	object_size: sizeof(*mod->syms), num: &mod->num_syms);
2578	mod->crcs = section_addr(info, name: "__kcrctab");
2579	mod->gpl_syms = section_objs(info, name: "__ksymtab_gpl",
2580	object_size: sizeof(*mod->gpl_syms),
2581	num: &mod->num_gpl_syms);
2582	mod->gpl_crcs = section_addr(info, name: "__kcrctab_gpl");
2583
2584	#ifdef CONFIG_CONSTRUCTORS
2585	mod->ctors = section_objs(info, name: ".ctors",
2586	object_size: sizeof(*mod->ctors), num: &mod->num_ctors);
2587	if (!mod->ctors)
2588	mod->ctors = section_objs(info, name: ".init_array",
2589	object_size: sizeof(*mod->ctors), num: &mod->num_ctors);
2590	else if (find_sec(info, name: ".init_array")) {
2591	/*
2592	* This shouldn't happen with same compiler and binutils
2593	* building all parts of the module.
2594	*/
2595	pr_warn("%s: has both .ctors and .init_array.\n",
2596	mod->name);
2597	return -EINVAL;
2598	}
2599	#endif
2600
2601	mod->noinstr_text_start = section_objs(info, name: ".noinstr.text", object_size: 1,
2602	num: &mod->noinstr_text_size);
2603
2604	#ifdef CONFIG_TRACEPOINTS
2605	mod->tracepoints_ptrs = section_objs(info, name: "__tracepoints_ptrs",
2606	object_size: sizeof(*mod->tracepoints_ptrs),
2607	num: &mod->num_tracepoints);
2608	#endif
2609	#ifdef CONFIG_TREE_SRCU
2610	mod->srcu_struct_ptrs = section_objs(info, name: "___srcu_struct_ptrs",
2611	object_size: sizeof(*mod->srcu_struct_ptrs),
2612	num: &mod->num_srcu_structs);
2613	#endif
2614	#ifdef CONFIG_BPF_EVENTS
2615	mod->bpf_raw_events = section_objs(info, name: "__bpf_raw_tp_map",
2616	object_size: sizeof(*mod->bpf_raw_events),
2617	num: &mod->num_bpf_raw_events);
2618	#endif
2619	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
2620	mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size);
2621	mod->btf_base_data = any_section_objs(info, ".BTF.base", 1,
2622	&mod->btf_base_data_size);
2623	#endif
2624	#ifdef CONFIG_JUMP_LABEL
2625	mod->jump_entries = section_objs(info, name: "__jump_table",
2626	object_size: sizeof(*mod->jump_entries),
2627	num: &mod->num_jump_entries);
2628	#endif
2629	#ifdef CONFIG_EVENT_TRACING
2630	mod->trace_events = section_objs(info, name: "_ftrace_events",
2631	object_size: sizeof(*mod->trace_events),
2632	num: &mod->num_trace_events);
2633	mod->trace_evals = section_objs(info, name: "_ftrace_eval_map",
2634	object_size: sizeof(*mod->trace_evals),
2635	num: &mod->num_trace_evals);
2636	#endif
2637	#ifdef CONFIG_TRACING
2638	mod->trace_bprintk_fmt_start = section_objs(info, name: "__trace_printk_fmt",
2639	object_size: sizeof(*mod->trace_bprintk_fmt_start),
2640	num: &mod->num_trace_bprintk_fmt);
2641	#endif
2642	#ifdef CONFIG_FTRACE_MCOUNT_RECORD
2643	/* sechdrs[0].sh_size is always zero */
2644	mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION,
2645	object_size: sizeof(*mod->ftrace_callsites),
2646	num: &mod->num_ftrace_callsites);
2647	#endif
2648	#ifdef CONFIG_FUNCTION_ERROR_INJECTION
2649	mod->ei_funcs = section_objs(info, name: "_error_injection_whitelist",
2650	object_size: sizeof(*mod->ei_funcs),
2651	num: &mod->num_ei_funcs);
2652	#endif
2653	#ifdef CONFIG_KPROBES
2654	mod->kprobes_text_start = section_objs(info, name: ".kprobes.text", object_size: 1,
2655	num: &mod->kprobes_text_size);
2656	mod->kprobe_blacklist = section_objs(info, name: "_kprobe_blacklist",
2657	object_size: sizeof(unsigned long),
2658	num: &mod->num_kprobe_blacklist);
2659	#endif
2660	#ifdef CONFIG_PRINTK_INDEX
2661	mod->printk_index_start = section_objs(info, name: ".printk_index",
2662	object_size: sizeof(*mod->printk_index_start),
2663	num: &mod->printk_index_size);
2664	#endif
2665	#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
2666	mod->static_call_sites = section_objs(info, name: ".static_call_sites",
2667	object_size: sizeof(*mod->static_call_sites),
2668	num: &mod->num_static_call_sites);
2669	#endif
2670	#if IS_ENABLED(CONFIG_KUNIT)
2671	mod->kunit_suites = section_objs(info, name: ".kunit_test_suites",
2672	object_size: sizeof(*mod->kunit_suites),
2673	num: &mod->num_kunit_suites);
2674	mod->kunit_init_suites = section_objs(info, name: ".kunit_init_test_suites",
2675	object_size: sizeof(*mod->kunit_init_suites),
2676	num: &mod->num_kunit_init_suites);
2677	#endif
2678
2679	mod->extable = section_objs(info, name: "__ex_table",
2680	object_size: sizeof(*mod->extable), num: &mod->num_exentries);
2681
2682	if (section_addr(info, name: "__obsparm"))
2683	pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
2684
2685	#ifdef CONFIG_DYNAMIC_DEBUG_CORE
2686	mod->dyndbg_info.descs = section_objs(info, name: "__dyndbg",
2687	object_size: sizeof(*mod->dyndbg_info.descs),
2688	num: &mod->dyndbg_info.num_descs);
2689	mod->dyndbg_info.classes = section_objs(info, name: "__dyndbg_classes",
2690	object_size: sizeof(*mod->dyndbg_info.classes),
2691	num: &mod->dyndbg_info.num_classes);
2692	#endif
2693
2694	return 0;
2695	}
2696
2697	static int move_module(struct module *mod, struct load_info *info)
2698	{
2699	int i;
2700	enum mod_mem_type t = 0;
2701	int ret = -ENOMEM;
2702	bool codetag_section_found = false;
2703
2704	for_each_mod_mem_type(type) {
2705	if (!mod->mem[type].size) {
2706	mod->mem[type].base = NULL;
2707	continue;
2708	}
2709
2710	ret = module_memory_alloc(mod, type);
2711	if (ret) {
2712	t = type;
2713	goto out_err;
2714	}
2715	}
2716
2717	/* Transfer each section which specifies SHF_ALLOC */
2718	pr_debug("Final section addresses for %s:\n", mod->name);
2719	for (i = 0; i < info->hdr->e_shnum; i++) {
2720	void *dest;
2721	Elf_Shdr *shdr = &info->sechdrs[i];
2722	const char *sname;
2723
2724	if (!(shdr->sh_flags & SHF_ALLOC))
2725	continue;
2726
2727	sname = info->secstrings + shdr->sh_name;
2728	/*
2729	* Load codetag sections separately as they might still be used
2730	* after module unload.
2731	*/
2732	if (codetag_needs_module_section(mod, name: sname, size: shdr->sh_size)) {
2733	dest = codetag_alloc_module_section(mod, name: sname, size: shdr->sh_size,
2734	prepend: arch_mod_section_prepend(mod, section: i), align: shdr->sh_addralign);
2735	if (WARN_ON(!dest)) {
2736	ret = -EINVAL;
2737	goto out_err;
2738	}
2739	if (IS_ERR(ptr: dest)) {
2740	ret = PTR_ERR(ptr: dest);
2741	goto out_err;
2742	}
2743	codetag_section_found = true;
2744	} else {
2745	enum mod_mem_type type = shdr->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
2746	unsigned long offset = shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK;
2747
2748	dest = mod->mem[type].base + offset;
2749	}
2750
2751	if (shdr->sh_type != SHT_NOBITS) {
2752	/*
2753	* Our ELF checker already validated this, but let's
2754	* be pedantic and make the goal clearer. We actually
2755	* end up copying over all modifications made to the
2756	* userspace copy of the entire struct module.
2757	*/
2758	if (i == info->index.mod &&
2759	(WARN_ON_ONCE(shdr->sh_size != sizeof(struct module)))) {
2760	ret = -ENOEXEC;
2761	goto out_err;
2762	}
2763	memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
2764	}
2765	/*
2766	* Update the userspace copy's ELF section address to point to
2767	* our newly allocated memory as a pure convenience so that
2768	* users of info can keep taking advantage and using the newly
2769	* minted official memory area.
2770	*/
2771	shdr->sh_addr = (unsigned long)dest;
2772	pr_debug("\t0x%lx 0x%.8lx %s\n", (long)shdr->sh_addr,
2773	(long)shdr->sh_size, info->secstrings + shdr->sh_name);
2774	}
2775
2776	return 0;
2777	out_err:
2778	module_memory_restore_rox(mod);
2779	for (t--; t >= 0; t--)
2780	module_memory_free(mod, type: t);
2781	if (codetag_section_found)
2782	codetag_free_module_sections(mod);
2783
2784	return ret;
2785	}
2786
2787	static int check_export_symbol_versions(struct module *mod)
2788	{
2789	#ifdef CONFIG_MODVERSIONS
2790	if ((mod->num_syms && !mod->crcs) ||
2791	(mod->num_gpl_syms && !mod->gpl_crcs)) {
2792	return try_to_force_load(mod,
2793	"no versions for exported symbols");
2794	}
2795	#endif
2796	return 0;
2797	}
2798
2799	static void flush_module_icache(const struct module *mod)
2800	{
2801	/*
2802	* Flush the instruction cache, since we've played with text.
2803	* Do it before processing of module parameters, so the module
2804	* can provide parameter accessor functions of its own.
2805	*/
2806	for_each_mod_mem_type(type) {
2807	const struct module_memory *mod_mem = &mod->mem[type];
2808
2809	if (mod_mem->size) {
2810	flush_icache_range(start: (unsigned long)mod_mem->base,
2811	end: (unsigned long)mod_mem->base + mod_mem->size);
2812	}
2813	}
2814	}
2815
2816	bool __weak module_elf_check_arch(Elf_Ehdr *hdr)
2817	{
2818	return true;
2819	}
2820
2821	int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
2822	Elf_Shdr *sechdrs,
2823	char *secstrings,
2824	struct module *mod)
2825	{
2826	return 0;
2827	}
2828
2829	/* module_blacklist is a comma-separated list of module names */
2830	static char *module_blacklist;
2831	static bool blacklisted(const char *module_name)
2832	{
2833	const char *p;
2834	size_t len;
2835
2836	if (!module_blacklist)
2837	return false;
2838
2839	for (p = module_blacklist; *p; p += len) {
2840	len = strcspn(p, ",");
2841	if (strlen(module_name) == len && !memcmp(p: module_name, q: p, size: len))
2842	return true;
2843	if (p[len] == ',')
2844	len++;
2845	}
2846	return false;
2847	}
2848	core_param(module_blacklist, module_blacklist, charp, 0400);
2849
2850	static struct module *layout_and_allocate(struct load_info *info, int flags)
2851	{
2852	struct module *mod;
2853	int err;
2854
2855	/* Allow arches to frob section contents and sizes. */
2856	err = module_frob_arch_sections(hdr: info->hdr, sechdrs: info->sechdrs,
2857	secstrings: info->secstrings, mod: info->mod);
2858	if (err < 0)
2859	return ERR_PTR(error: err);
2860
2861	err = module_enforce_rwx_sections(hdr: info->hdr, sechdrs: info->sechdrs,
2862	secstrings: info->secstrings, mod: info->mod);
2863	if (err < 0)
2864	return ERR_PTR(error: err);
2865
2866	/* We will do a special allocation for per-cpu sections later. */
2867	info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
2868
2869	/*
2870	* Mark relevant sections as SHF_RO_AFTER_INIT so layout_sections() can
2871	* put them in the right place.
2872	* Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
2873	*/
2874	module_mark_ro_after_init(hdr: info->hdr, sechdrs: info->sechdrs, secstrings: info->secstrings);
2875
2876	/*
2877	* Determine total sizes, and put offsets in sh_entsize. For now
2878	* this is done generically; there doesn't appear to be any
2879	* special cases for the architectures.
2880	*/
2881	layout_sections(mod: info->mod, info);
2882	layout_symtab(mod: info->mod, info);
2883
2884	/* Allocate and move to the final place */
2885	err = move_module(mod: info->mod, info);
2886	if (err)
2887	return ERR_PTR(error: err);
2888
2889	/* Module has been copied to its final place now: return it. */
2890	mod = (void *)info->sechdrs[info->index.mod].sh_addr;
2891	kmemleak_load_module(mod, info);
2892	codetag_module_replaced(mod: info->mod, new_mod: mod);
2893
2894	return mod;
2895	}
2896
2897	/* mod is no longer valid after this! */
2898	static void module_deallocate(struct module *mod, struct load_info *info)
2899	{
2900	percpu_modfree(mod);
2901	module_arch_freeing_init(mod);
2902	codetag_free_module_sections(mod);
2903
2904	free_mod_mem(mod);
2905	}
2906
2907	int __weak module_finalize(const Elf_Ehdr *hdr,
2908	const Elf_Shdr *sechdrs,
2909	struct module *me)
2910	{
2911	return 0;
2912	}
2913
2914	static int post_relocation(struct module *mod, const struct load_info *info)
2915	{
2916	/* Sort exception table now relocations are done. */
2917	sort_extable(start: mod->extable, finish: mod->extable + mod->num_exentries);
2918
2919	/* Copy relocated percpu area over. */
2920	percpu_modcopy(mod, from: (void *)info->sechdrs[info->index.pcpu].sh_addr,
2921	size: info->sechdrs[info->index.pcpu].sh_size);
2922
2923	/* Setup kallsyms-specific fields. */
2924	add_kallsyms(mod, info);
2925
2926	/* Arch-specific module finalizing. */
2927	return module_finalize(hdr: info->hdr, sechdrs: info->sechdrs, me: mod);
2928	}
2929
2930	/* Call module constructors. */
2931	static void do_mod_ctors(struct module *mod)
2932	{
2933	#ifdef CONFIG_CONSTRUCTORS
2934	unsigned long i;
2935
2936	for (i = 0; i < mod->num_ctors; i++)
2937	mod->ctors[i]();
2938	#endif
2939	}
2940
2941	/* For freeing module_init on success, in case kallsyms traversing */
2942	struct mod_initfree {
2943	struct llist_node node;
2944	void *init_text;
2945	void *init_data;
2946	void *init_rodata;
2947	};
2948
2949	static void do_free_init(struct work_struct *w)
2950	{
2951	struct llist_node *pos, *n, *list;
2952	struct mod_initfree *initfree;
2953
2954	list = llist_del_all(head: &init_free_list);
2955
2956	synchronize_rcu();
2957
2958	llist_for_each_safe(pos, n, list) {
2959	initfree = container_of(pos, struct mod_initfree, node);
2960	execmem_free(ptr: initfree->init_text);
2961	execmem_free(ptr: initfree->init_data);
2962	execmem_free(ptr: initfree->init_rodata);
2963	kfree(objp: initfree);
2964	}
2965	}
2966
2967	void flush_module_init_free_work(void)
2968	{
2969	flush_work(work: &init_free_wq);
2970	}
2971
2972	#undef MODULE_PARAM_PREFIX
2973	#define MODULE_PARAM_PREFIX "module."
2974	/* Default value for module->async_probe_requested */
2975	static bool async_probe;
2976	module_param(async_probe, bool, 0644);
2977
2978	/*
2979	* This is where the real work happens.
2980	*
2981	* Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
2982	* helper command 'lx-symbols'.
2983	*/
2984	static noinline int do_init_module(struct module *mod)
2985	{
2986	int ret = 0;
2987	struct mod_initfree *freeinit;
2988	#if defined(CONFIG_MODULE_STATS)
2989	unsigned int text_size = 0, total_size = 0;
2990
2991	for_each_mod_mem_type(type) {
2992	const struct module_memory *mod_mem = &mod->mem[type];
2993	if (mod_mem->size) {
2994	total_size += mod_mem->size;
2995	if (type == MOD_TEXT || type == MOD_INIT_TEXT)
2996	text_size += mod_mem->size;
2997	}
2998	}
2999	#endif
3000
3001	freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3002	if (!freeinit) {
3003	ret = -ENOMEM;
3004	goto fail;
3005	}
3006	freeinit->init_text = mod->mem[MOD_INIT_TEXT].base;
3007	freeinit->init_data = mod->mem[MOD_INIT_DATA].base;
3008	freeinit->init_rodata = mod->mem[MOD_INIT_RODATA].base;
3009
3010	do_mod_ctors(mod);
3011	/* Start the module */
3012	if (mod->init != NULL)
3013	ret = do_one_initcall(fn: mod->init);
3014	if (ret < 0) {
3015	goto fail_free_freeinit;
3016	}
3017	if (ret > 0) {
3018	pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3019	"follow 0/-E convention\n"
3020	"%s: loading module anyway...\n",
3021	__func__, mod->name, ret, __func__);
3022	dump_stack();
3023	}
3024
3025	/* Now it's a first class citizen! */
3026	mod->state = MODULE_STATE_LIVE;
3027	blocking_notifier_call_chain(nh: &module_notify_list,
3028	val: MODULE_STATE_LIVE, v: mod);
3029
3030	/* Delay uevent until module has finished its init routine */
3031	kobject_uevent(kobj: &mod->mkobj.kobj, action: KOBJ_ADD);
3032
3033	/*
3034	* We need to finish all async code before the module init sequence
3035	* is done. This has potential to deadlock if synchronous module
3036	* loading is requested from async (which is not allowed!).
3037	*
3038	* See commit 0fdff3ec6d87 ("async, kmod: warn on synchronous
3039	* request_module() from async workers") for more details.
3040	*/
3041	if (!mod->async_probe_requested)
3042	async_synchronize_full();
3043
3044	ftrace_free_mem(mod, start: mod->mem[MOD_INIT_TEXT].base,
3045	end: mod->mem[MOD_INIT_TEXT].base + mod->mem[MOD_INIT_TEXT].size);
3046	mutex_lock(&module_mutex);
3047	/* Drop initial reference. */
3048	module_put(mod);
3049	trim_init_extable(m: mod);
3050	#ifdef CONFIG_KALLSYMS
3051	/* Switch to core kallsyms now init is done: kallsyms may be walking! */
3052	rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
3053	#endif
3054	ret = module_enable_rodata_ro_after_init(mod);
3055	if (ret)
3056	pr_warn("%s: module_enable_rodata_ro_after_init() returned %d, "
3057	"ro_after_init data might still be writable\n",
3058	mod->name, ret);
3059
3060	mod_tree_remove_init(mod);
3061	module_arch_freeing_init(mod);
3062	for_class_mod_mem_type(type, init) {
3063	mod->mem[type].base = NULL;
3064	mod->mem[type].size = 0;
3065	}
3066
3067	#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
3068	/* .BTF is not SHF_ALLOC and will get removed, so sanitize pointers */
3069	mod->btf_data = NULL;
3070	mod->btf_base_data = NULL;
3071	#endif
3072	/*
3073	* We want to free module_init, but be aware that kallsyms may be
3074	* walking this within an RCU read section. In all the failure paths, we
3075	* call synchronize_rcu(), but we don't want to slow down the success
3076	* path. execmem_free() cannot be called in an interrupt, so do the
3077	* work and call synchronize_rcu() in a work queue.
3078	*
3079	* Note that execmem_alloc() on most architectures creates W+X page
3080	* mappings which won't be cleaned up until do_free_init() runs. Any
3081	* code such as mark_rodata_ro() which depends on those mappings to
3082	* be cleaned up needs to sync with the queued work by invoking
3083	* flush_module_init_free_work().
3084	*/
3085	if (llist_add(new: &freeinit->node, head: &init_free_list))
3086	schedule_work(work: &init_free_wq);
3087
3088	mutex_unlock(lock: &module_mutex);
3089	wake_up_all(&module_wq);
3090
3091	mod_stat_add_long(text_size, &total_text_size);
3092	mod_stat_add_long(total_size, &total_mod_size);
3093
3094	mod_stat_inc(&modcount);
3095
3096	return 0;
3097
3098	fail_free_freeinit:
3099	kfree(objp: freeinit);
3100	fail:
3101	/* Try to protect us from buggy refcounters. */
3102	mod->state = MODULE_STATE_GOING;
3103	synchronize_rcu();
3104	module_put(mod);
3105	blocking_notifier_call_chain(nh: &module_notify_list,
3106	val: MODULE_STATE_GOING, v: mod);
3107	klp_module_going(mod);
3108	ftrace_release_mod(mod);
3109	free_module(mod);
3110	wake_up_all(&module_wq);
3111
3112	return ret;
3113	}
3114
3115	static int may_init_module(void)
3116	{
3117	if (!capable(CAP_SYS_MODULE) || modules_disabled)
3118	return -EPERM;
3119
3120	return 0;
3121	}
3122
3123	/* Is this module of this name done loading? No locks held. */
3124	static bool finished_loading(const char *name)
3125	{
3126	struct module *mod;
3127	bool ret;
3128
3129	/*
3130	* The module_mutex should not be a heavily contended lock;
3131	* if we get the occasional sleep here, we'll go an extra iteration
3132	* in the wait_event_interruptible(), which is harmless.
3133	*/
3134	sched_annotate_sleep();
3135	mutex_lock(&module_mutex);
3136	mod = find_module_all(name, strlen(name), even_unformed: true);
3137	ret = !mod || mod->state == MODULE_STATE_LIVE
3138	|| mod->state == MODULE_STATE_GOING;
3139	mutex_unlock(lock: &module_mutex);
3140
3141	return ret;
3142	}
3143
3144	/* Must be called with module_mutex held */
3145	static int module_patient_check_exists(const char *name,
3146	enum fail_dup_mod_reason reason)
3147	{
3148	struct module *old;
3149	int err = 0;
3150
3151	old = find_module_all(name, strlen(name), even_unformed: true);
3152	if (old == NULL)
3153	return 0;
3154
3155	if (old->state == MODULE_STATE_COMING ||
3156	old->state == MODULE_STATE_UNFORMED) {
3157	/* Wait in case it fails to load. */
3158	mutex_unlock(lock: &module_mutex);
3159	err = wait_event_interruptible(module_wq,
3160	finished_loading(name));
3161	mutex_lock(&module_mutex);
3162	if (err)
3163	return err;
3164
3165	/* The module might have gone in the meantime. */
3166	old = find_module_all(name, strlen(name), even_unformed: true);
3167	}
3168
3169	if (try_add_failed_module(name, reason))
3170	pr_warn("Could not add fail-tracking for module: %s\n", name);
3171
3172	/*
3173	* We are here only when the same module was being loaded. Do
3174	* not try to load it again right now. It prevents long delays
3175	* caused by serialized module load failures. It might happen
3176	* when more devices of the same type trigger load of
3177	* a particular module.
3178	*/
3179	if (old && old->state == MODULE_STATE_LIVE)
3180	return -EEXIST;
3181	return -EBUSY;
3182	}
3183
3184	/*
3185	* We try to place it in the list now to make sure it's unique before
3186	* we dedicate too many resources. In particular, temporary percpu
3187	* memory exhaustion.
3188	*/
3189	static int add_unformed_module(struct module *mod)
3190	{
3191	int err;
3192
3193	mod->state = MODULE_STATE_UNFORMED;
3194
3195	mutex_lock(&module_mutex);
3196	err = module_patient_check_exists(name: mod->name, reason: FAIL_DUP_MOD_LOAD);
3197	if (err)
3198	goto out;
3199
3200	mod_update_bounds(mod);
3201	list_add_rcu(new: &mod->list, head: &modules);
3202	mod_tree_insert(mod);
3203	err = 0;
3204
3205	out:
3206	mutex_unlock(lock: &module_mutex);
3207	return err;
3208	}
3209
3210	static int complete_formation(struct module *mod, struct load_info *info)
3211	{
3212	int err;
3213
3214	mutex_lock(&module_mutex);
3215
3216	/* Find duplicate symbols (must be called under lock). */
3217	err = verify_exported_symbols(mod);
3218	if (err < 0)
3219	goto out;
3220
3221	/* These rely on module_mutex for list integrity. */
3222	module_bug_finalize(info->hdr, info->sechdrs, mod);
3223	module_cfi_finalize(hdr: info->hdr, sechdrs: info->sechdrs, mod);
3224
3225	err = module_enable_rodata_ro(mod);
3226	if (err)
3227	goto out_strict_rwx;
3228	err = module_enable_data_nx(mod);
3229	if (err)
3230	goto out_strict_rwx;
3231	err = module_enable_text_rox(mod);
3232	if (err)
3233	goto out_strict_rwx;
3234
3235	/*
3236	* Mark state as coming so strong_try_module_get() ignores us,
3237	* but kallsyms etc. can see us.
3238	*/
3239	mod->state = MODULE_STATE_COMING;
3240	mutex_unlock(lock: &module_mutex);
3241
3242	return 0;
3243
3244	out_strict_rwx:
3245	module_bug_cleanup(mod);
3246	out:
3247	mutex_unlock(lock: &module_mutex);
3248	return err;
3249	}
3250
3251	static int prepare_coming_module(struct module *mod)
3252	{
3253	int err;
3254
3255	ftrace_module_enable(mod);
3256	err = klp_module_coming(mod);
3257	if (err)
3258	return err;
3259
3260	err = blocking_notifier_call_chain_robust(nh: &module_notify_list,
3261	val_up: MODULE_STATE_COMING, val_down: MODULE_STATE_GOING, v: mod);
3262	err = notifier_to_errno(ret: err);
3263	if (err)
3264	klp_module_going(mod);
3265
3266	return err;
3267	}
3268
3269	static int unknown_module_param_cb(char *param, char *val, const char *modname,
3270	void *arg)
3271	{
3272	struct module *mod = arg;
3273	int ret;
3274
3275	if (strcmp(param, "async_probe") == 0) {
3276	if (kstrtobool(s: val, res: &mod->async_probe_requested))
3277	mod->async_probe_requested = true;
3278	return 0;
3279	}
3280
3281	/* Check for magic 'dyndbg' arg */
3282	ret = ddebug_dyndbg_module_param_cb(param, val, modname);
3283	if (ret != 0)
3284	pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
3285	return 0;
3286	}
3287
3288	/* Module within temporary copy, this doesn't do any allocation */
3289	static int early_mod_check(struct load_info *info, int flags)
3290	{
3291	int err;
3292
3293	/*
3294	* Now that we know we have the correct module name, check
3295	* if it's blacklisted.
3296	*/
3297	if (blacklisted(module_name: info->name)) {
3298	pr_err("Module %s is blacklisted\n", info->name);
3299	return -EPERM;
3300	}
3301
3302	err = rewrite_section_headers(info, flags);
3303	if (err)
3304	return err;
3305
3306	/* Check module struct version now, before we try to use module. */
3307	if (!check_modstruct_version(info, mod: info->mod))
3308	return -ENOEXEC;
3309
3310	err = check_modinfo(mod: info->mod, info, flags);
3311	if (err)
3312	return err;
3313
3314	mutex_lock(&module_mutex);
3315	err = module_patient_check_exists(name: info->mod->name, reason: FAIL_DUP_MOD_BECOMING);
3316	mutex_unlock(lock: &module_mutex);
3317
3318	return err;
3319	}
3320
3321	/*
3322	* Allocate and load the module: note that size of section 0 is always
3323	* zero, and we rely on this for optional sections.
3324	*/
3325	static int load_module(struct load_info *info, const char __user *uargs,
3326	int flags)
3327	{
3328	struct module *mod;
3329	bool module_allocated = false;
3330	long err = 0;
3331	char *after_dashes;
3332
3333	/*
3334	* Do the signature check (if any) first. All that
3335	* the signature check needs is info->len, it does
3336	* not need any of the section info. That can be
3337	* set up later. This will minimize the chances
3338	* of a corrupt module causing problems before
3339	* we even get to the signature check.
3340	*
3341	* The check will also adjust info->len by stripping
3342	* off the sig length at the end of the module, making
3343	* checks against info->len more correct.
3344	*/
3345	err = module_sig_check(info, flags);
3346	if (err)
3347	goto free_copy;
3348
3349	/*
3350	* Do basic sanity checks against the ELF header and
3351	* sections. Cache useful sections and set the
3352	* info->mod to the userspace passed struct module.
3353	*/
3354	err = elf_validity_cache_copy(info, flags);
3355	if (err)
3356	goto free_copy;
3357
3358	err = early_mod_check(info, flags);
3359	if (err)
3360	goto free_copy;
3361
3362	/* Figure out module layout, and allocate all the memory. */
3363	mod = layout_and_allocate(info, flags);
3364	if (IS_ERR(ptr: mod)) {
3365	err = PTR_ERR(ptr: mod);
3366	goto free_copy;
3367	}
3368
3369	module_allocated = true;
3370
3371	audit_log_kern_module(name: mod->name);
3372
3373	/* Reserve our place in the list. */
3374	err = add_unformed_module(mod);
3375	if (err)
3376	goto free_module;
3377
3378	/*
3379	* We are tainting your kernel if your module gets into
3380	* the modules linked list somehow.
3381	*/
3382	module_augment_kernel_taints(mod, info);
3383
3384	/* To avoid stressing percpu allocator, do this once we're unique. */
3385	err = percpu_modalloc(mod, info);
3386	if (err)
3387	goto unlink_mod;
3388
3389	/* Now module is in final location, initialize linked lists, etc. */
3390	err = module_unload_init(mod);
3391	if (err)
3392	goto unlink_mod;
3393
3394	init_param_lock(mod);
3395
3396	/*
3397	* Now we've got everything in the final locations, we can
3398	* find optional sections.
3399	*/
3400	err = find_module_sections(mod, info);
3401	if (err)
3402	goto free_unload;
3403
3404	err = check_export_symbol_versions(mod);
3405	if (err)
3406	goto free_unload;
3407
3408	/* Set up MODINFO_ATTR fields */
3409	err = setup_modinfo(mod, info);
3410	if (err)
3411	goto free_modinfo;
3412
3413	/* Fix up syms, so that st_value is a pointer to location. */
3414	err = simplify_symbols(mod, info);
3415	if (err < 0)
3416	goto free_modinfo;
3417
3418	err = apply_relocations(mod, info);
3419	if (err < 0)
3420	goto free_modinfo;
3421
3422	err = post_relocation(mod, info);
3423	if (err < 0)
3424	goto free_modinfo;
3425
3426	flush_module_icache(mod);
3427
3428	/* Now copy in args */
3429	mod->args = strndup_user(uargs, ~0UL >> 1);
3430	if (IS_ERR(ptr: mod->args)) {
3431	err = PTR_ERR(ptr: mod->args);
3432	goto free_arch_cleanup;
3433	}
3434
3435	init_build_id(mod, info);
3436
3437	/* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3438	ftrace_module_init(mod);
3439
3440	/* Finally it's fully formed, ready to start executing. */
3441	err = complete_formation(mod, info);
3442	if (err)
3443	goto ddebug_cleanup;
3444
3445	err = prepare_coming_module(mod);
3446	if (err)
3447	goto bug_cleanup;
3448
3449	mod->async_probe_requested = async_probe;
3450
3451	/* Module is ready to execute: parsing args may do that. */
3452	after_dashes = parse_args(name: mod->name, args: mod->args, params: mod->kp, num: mod->num_kp,
3453	level_min: -32768, level_max: 32767, arg: mod,
3454	unknown: unknown_module_param_cb);
3455	if (IS_ERR(ptr: after_dashes)) {
3456	err = PTR_ERR(ptr: after_dashes);
3457	goto coming_cleanup;
3458	} else if (after_dashes) {
3459	pr_warn("%s: parameters '%s' after `--' ignored\n",
3460	mod->name, after_dashes);
3461	}
3462
3463	/* Link in to sysfs. */
3464	err = mod_sysfs_setup(mod, info, kparam: mod->kp, num_params: mod->num_kp);
3465	if (err < 0)
3466	goto coming_cleanup;
3467
3468	if (is_livepatch_module(mod)) {
3469	err = copy_module_elf(mod, info);
3470	if (err < 0)
3471	goto sysfs_cleanup;
3472	}
3473
3474	if (codetag_load_module(mod))
3475	goto sysfs_cleanup;
3476
3477	/* Get rid of temporary copy. */
3478	free_copy(info, flags);
3479
3480	/* Done! */
3481	trace_module_load(mod);
3482
3483	return do_init_module(mod);
3484
3485	sysfs_cleanup:
3486	mod_sysfs_teardown(mod);
3487	coming_cleanup:
3488	mod->state = MODULE_STATE_GOING;
3489	destroy_params(params: mod->kp, num: mod->num_kp);
3490	blocking_notifier_call_chain(nh: &module_notify_list,
3491	val: MODULE_STATE_GOING, v: mod);
3492	klp_module_going(mod);
3493	bug_cleanup:
3494	mod->state = MODULE_STATE_GOING;
3495	/* module_bug_cleanup needs module_mutex protection */
3496	mutex_lock(&module_mutex);
3497	module_bug_cleanup(mod);
3498	mutex_unlock(lock: &module_mutex);
3499
3500	ddebug_cleanup:
3501	ftrace_release_mod(mod);
3502	synchronize_rcu();
3503	kfree(objp: mod->args);
3504	free_arch_cleanup:
3505	module_arch_cleanup(mod);
3506	free_modinfo:
3507	free_modinfo(mod);
3508	free_unload:
3509	module_unload_free(mod);
3510	unlink_mod:
3511	mutex_lock(&module_mutex);
3512	/* Unlink carefully: kallsyms could be walking list. */
3513	list_del_rcu(entry: &mod->list);
3514	mod_tree_remove(mod);
3515	wake_up_all(&module_wq);
3516	/* Wait for RCU-sched synchronizing before releasing mod->list. */
3517	synchronize_rcu();
3518	mutex_unlock(lock: &module_mutex);
3519	free_module:
3520	mod_stat_bump_invalid(info, flags);
3521	/* Free lock-classes; relies on the preceding sync_rcu() */
3522	for_class_mod_mem_type(type, core_data) {
3523	lockdep_free_key_range(start: mod->mem[type].base,
3524	size: mod->mem[type].size);
3525	}
3526
3527	module_memory_restore_rox(mod);
3528	module_deallocate(mod, info);
3529	free_copy:
3530	/*
3531	* The info->len is always set. We distinguish between
3532	* failures once the proper module was allocated and
3533	* before that.
3534	*/
3535	if (!module_allocated)
3536	mod_stat_bump_becoming(info, flags);
3537	free_copy(info, flags);
3538	return err;
3539	}
3540
3541	SYSCALL_DEFINE3(init_module, void __user *, umod,
3542	unsigned long, len, const char __user *, uargs)
3543	{
3544	int err;
3545	struct load_info info = { };
3546
3547	err = may_init_module();
3548	if (err)
3549	return err;
3550
3551	pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3552	umod, len, uargs);
3553
3554	err = copy_module_from_user(umod, len, info: &info);
3555	if (err) {
3556	mod_stat_inc(&failed_kreads);
3557	mod_stat_add_long(len, &invalid_kread_bytes);
3558	return err;
3559	}
3560
3561	return load_module(info: &info, uargs, flags: 0);
3562	}
3563
3564	struct idempotent {
3565	const void *cookie;
3566	struct hlist_node entry;
3567	struct completion complete;
3568	int ret;
3569	};
3570
3571	#define IDEM_HASH_BITS 8
3572	static struct hlist_head idem_hash[1 << IDEM_HASH_BITS];
3573	static DEFINE_SPINLOCK(idem_lock);
3574
3575	static bool idempotent(struct idempotent *u, const void *cookie)
3576	{
3577	int hash = hash_ptr(ptr: cookie, IDEM_HASH_BITS);
3578	struct hlist_head *head = idem_hash + hash;
3579	struct idempotent *existing;
3580	bool first;
3581
3582	u->ret = -EINTR;
3583	u->cookie = cookie;
3584	init_completion(x: &u->complete);
3585
3586	spin_lock(lock: &idem_lock);
3587	first = true;
3588	hlist_for_each_entry(existing, head, entry) {
3589	if (existing->cookie != cookie)
3590	continue;
3591	first = false;
3592	break;
3593	}
3594	hlist_add_head(n: &u->entry, h: idem_hash + hash);
3595	spin_unlock(lock: &idem_lock);
3596
3597	return !first;
3598	}
3599
3600	/*
3601	* We were the first one with 'cookie' on the list, and we ended
3602	* up completing the operation. We now need to walk the list,
3603	* remove everybody - which includes ourselves - fill in the return
3604	* value, and then complete the operation.
3605	*/
3606	static int idempotent_complete(struct idempotent *u, int ret)
3607	{
3608	const void *cookie = u->cookie;
3609	int hash = hash_ptr(ptr: cookie, IDEM_HASH_BITS);
3610	struct hlist_head *head = idem_hash + hash;
3611	struct hlist_node *next;
3612	struct idempotent *pos;
3613
3614	spin_lock(lock: &idem_lock);
3615	hlist_for_each_entry_safe(pos, next, head, entry) {
3616	if (pos->cookie != cookie)
3617	continue;
3618	hlist_del_init(n: &pos->entry);
3619	pos->ret = ret;
3620	complete(&pos->complete);
3621	}
3622	spin_unlock(lock: &idem_lock);
3623	return ret;
3624	}
3625
3626	/*
3627	* Wait for the idempotent worker.
3628	*
3629	* If we get interrupted, we need to remove ourselves from the
3630	* the idempotent list, and the completion may still come in.
3631	*
3632	* The 'idem_lock' protects against the race, and 'idem.ret' was
3633	* initialized to -EINTR and is thus always the right return
3634	* value even if the idempotent work then completes between
3635	* the wait_for_completion and the cleanup.
3636	*/
3637	static int idempotent_wait_for_completion(struct idempotent *u)
3638	{
3639	if (wait_for_completion_interruptible(x: &u->complete)) {
3640	spin_lock(lock: &idem_lock);
3641	if (!hlist_unhashed(h: &u->entry))
3642	hlist_del(n: &u->entry);
3643	spin_unlock(lock: &idem_lock);
3644	}
3645	return u->ret;
3646	}
3647
3648	static int init_module_from_file(struct file *f, const char __user * uargs, int flags)
3649	{
3650	struct load_info info = { };
3651	void *buf = NULL;
3652	int len;
3653
3654	len = kernel_read_file(file: f, offset: 0, buf: &buf, INT_MAX, NULL, id: READING_MODULE);
3655	if (len < 0) {
3656	mod_stat_inc(&failed_kreads);
3657	return len;
3658	}
3659
3660	if (flags & MODULE_INIT_COMPRESSED_FILE) {
3661	int err = module_decompress(info: &info, buf, size: len);
3662	vfree(addr: buf); /* compressed data is no longer needed */
3663	if (err) {
3664	mod_stat_inc(&failed_decompress);
3665	mod_stat_add_long(len, &invalid_decompress_bytes);
3666	return err;
3667	}
3668	} else {
3669	info.hdr = buf;
3670	info.len = len;
3671	}
3672
3673	return load_module(info: &info, uargs, flags);
3674	}
3675
3676	static int idempotent_init_module(struct file *f, const char __user * uargs, int flags)
3677	{
3678	struct idempotent idem;
3679
3680	if (!(f->f_mode & FMODE_READ))
3681	return -EBADF;
3682
3683	/* Are we the winners of the race and get to do this? */
3684	if (!idempotent(u: &idem, cookie: file_inode(f))) {
3685	int ret = init_module_from_file(f, uargs, flags);
3686	return idempotent_complete(u: &idem, ret);
3687	}
3688
3689	/*
3690	* Somebody else won the race and is loading the module.
3691	*/
3692	return idempotent_wait_for_completion(u: &idem);
3693	}
3694
3695	SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
3696	{
3697	int err = may_init_module();
3698	if (err)
3699	return err;
3700
3701	pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3702
3703	if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3704	|MODULE_INIT_IGNORE_VERMAGIC
3705	|MODULE_INIT_COMPRESSED_FILE))
3706	return -EINVAL;
3707
3708	CLASS(fd, f)(fd);
3709	if (fd_empty(f))
3710	return -EBADF;
3711	return idempotent_init_module(fd_file(f), uargs, flags);
3712	}
3713
3714	/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
3715	char *module_flags(struct module *mod, char *buf, bool show_state)
3716	{
3717	int bx = 0;
3718
3719	BUG_ON(mod->state == MODULE_STATE_UNFORMED);
3720	if (!mod->taints && !show_state)
3721	goto out;
3722	if (mod->taints ||
3723	mod->state == MODULE_STATE_GOING ||
3724	mod->state == MODULE_STATE_COMING) {
3725	buf[bx++] = '(';
3726	bx += module_flags_taint(taints: mod->taints, buf: buf + bx);
3727	/* Show a - for module-is-being-unloaded */
3728	if (mod->state == MODULE_STATE_GOING && show_state)
3729	buf[bx++] = '-';
3730	/* Show a + for module-is-being-loaded */
3731	if (mod->state == MODULE_STATE_COMING && show_state)
3732	buf[bx++] = '+';
3733	buf[bx++] = ')';
3734	}
3735	out:
3736	buf[bx] = '\0';
3737
3738	return buf;
3739	}
3740
3741	/* Given an address, look for it in the module exception tables. */
3742	const struct exception_table_entry *search_module_extables(unsigned long addr)
3743	{
3744	struct module *mod;
3745
3746	guard(rcu)();
3747	mod = __module_address(addr);
3748	if (!mod)
3749	return NULL;
3750
3751	if (!mod->num_exentries)
3752	return NULL;
3753	/*
3754	* The address passed here belongs to a module that is currently
3755	* invoked (we are running inside it). Therefore its module::refcnt
3756	* needs already be >0 to ensure that it is not removed at this stage.
3757	* All other user need to invoke this function within a RCU read
3758	* section.
3759	*/
3760	return search_extable(base: mod->extable, num: mod->num_exentries, value: addr);
3761	}
3762
3763	/**
3764	* is_module_address() - is this address inside a module?
3765	* @addr: the address to check.
3766	*
3767	* See is_module_text_address() if you simply want to see if the address
3768	* is code (not data).
3769	*/
3770	bool is_module_address(unsigned long addr)
3771	{
3772	guard(rcu)();
3773	return __module_address(addr) != NULL;
3774	}
3775
3776	/**
3777	* __module_address() - get the module which contains an address.
3778	* @addr: the address.
3779	*
3780	* Must be called within RCU read section or module mutex held so that
3781	* module doesn't get freed during this.
3782	*/
3783	struct module *__module_address(unsigned long addr)
3784	{
3785	struct module *mod;
3786
3787	if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max)
3788	goto lookup;
3789
3790	#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
3791	if (addr >= mod_tree.data_addr_min && addr <= mod_tree.data_addr_max)
3792	goto lookup;
3793	#endif
3794
3795	return NULL;
3796
3797	lookup:
3798	mod = mod_find(addr, tree: &mod_tree);
3799	if (mod) {
3800	BUG_ON(!within_module(addr, mod));
3801	if (mod->state == MODULE_STATE_UNFORMED)
3802	mod = NULL;
3803	}
3804	return mod;
3805	}
3806
3807	/**
3808	* is_module_text_address() - is this address inside module code?
3809	* @addr: the address to check.
3810	*
3811	* See is_module_address() if you simply want to see if the address is
3812	* anywhere in a module. See kernel_text_address() for testing if an
3813	* address corresponds to kernel or module code.
3814	*/
3815	bool is_module_text_address(unsigned long addr)
3816	{
3817	guard(rcu)();
3818	return __module_text_address(addr) != NULL;
3819	}
3820
3821	void module_for_each_mod(int(*func)(struct module *mod, void *data), void *data)
3822	{
3823	struct module *mod;
3824
3825	guard(rcu)();
3826	list_for_each_entry_rcu(mod, &modules, list) {
3827	if (mod->state == MODULE_STATE_UNFORMED)
3828	continue;
3829	if (func(mod, data))
3830	break;
3831	}
3832	}
3833
3834	/**
3835	* __module_text_address() - get the module whose code contains an address.
3836	* @addr: the address.
3837	*
3838	* Must be called within RCU read section or module mutex held so that
3839	* module doesn't get freed during this.
3840	*/
3841	struct module *__module_text_address(unsigned long addr)
3842	{
3843	struct module *mod = __module_address(addr);
3844	if (mod) {
3845	/* Make sure it's within the text section. */
3846	if (!within_module_mem_type(addr, mod, type: MOD_TEXT) &&
3847	!within_module_mem_type(addr, mod, type: MOD_INIT_TEXT))
3848	mod = NULL;
3849	}
3850	return mod;
3851	}
3852
3853	/* Don't grab lock, we're oopsing. */
3854	void print_modules(void)
3855	{
3856	struct module *mod;
3857	char buf[MODULE_FLAGS_BUF_SIZE];
3858
3859	printk(KERN_DEFAULT "Modules linked in:");
3860	/* Most callers should already have preempt disabled, but make sure */
3861	guard(rcu)();
3862	list_for_each_entry_rcu(mod, &modules, list) {
3863	if (mod->state == MODULE_STATE_UNFORMED)
3864	continue;
3865	pr_cont(" %s%s", mod->name, module_flags(mod, buf, true));
3866	}
3867
3868	print_unloaded_tainted_modules();
3869	if (last_unloaded_module.name[0])
3870	pr_cont(" [last unloaded: %s%s]", last_unloaded_module.name,
3871	last_unloaded_module.taints);
3872	pr_cont("\n");
3873	}
3874
3875	#ifdef CONFIG_MODULE_DEBUGFS
3876	struct dentry *mod_debugfs_root;
3877
3878	static int module_debugfs_init(void)
3879	{
3880	mod_debugfs_root = debugfs_create_dir(name: "modules", NULL);
3881	return 0;
3882	}
3883	module_init(module_debugfs_init);
3884	#endif
3885