// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2002 Richard Henderson * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM. * Copyright (C) 2023 Luis Chamberlain <mcgrof@kernel.org> * Copyright (C) 2024 Mike Rapoport IBM. */ #include <linux/mm.h>#include <linux/vmalloc.h>#include <linux/execmem.h>#include <linux/moduleloader.h> static struct execmem_info *execmem_info __ro_after_init;static struct execmem_info default_execmem_info __ro_after_init; static void *__execmem_alloc(struct execmem_range *range, size_t size){	bool kasan = range->flags & EXECMEM_KASAN_SHADOW;	unsigned long vm_flags  = VM_FLUSH_RESET_PERMS;	gfp_t gfp_flags = GFP_KERNEL | __GFP_NOWARN;	unsigned long start = range->start;	unsigned long end = range->end;	unsigned int align = range->alignment;	pgprot_t pgprot = range->pgprot;	void *p; 	if (kasan)		vm_flags |= VM_DEFER_KMEMLEAK; 	p = __vmalloc_node_range(size, align, start, end, gfp_flags,				 pgprot, vm_flags, NUMA_NO_NODE,				 __builtin_return_address(0));	if (!p && range->fallback_start) {		start = range->fallback_start;		end = range->fallback_end;		p = __vmalloc_node_range(size, align, start, end, gfp_flags,					 pgprot, vm_flags, NUMA_NO_NODE,					 __builtin_return_address(0));	} 	if (!p) {		pr_warn_ratelimited("execmem: unable to allocate memory\n");		return NULL;	} 	if (kasan && (kasan_alloc_module_shadow(p, size, GFP_KERNEL) < 0)) {		vfree(p);		return NULL;	} 	return kasan_reset_tag(p);} void *execmem_alloc(enum execmem_type type, size_t size){	struct execmem_range *range = &execmem_info->ranges[type]; 	return __execmem_alloc(range, size);} void execmem_free(void *ptr){	/*	 * This memory may be RO, and freeing RO memory in an interrupt is not	 * supported by vmalloc.	 */	WARN_ON(in_interrupt());	vfree(ptr);} static bool execmem_validate(struct execmem_info *info){	struct execmem_range *r = &info->ranges[EXECMEM_DEFAULT]; 	if (!r->alignment || !r->start || !r->end || !pgprot_val(r->pgprot)) {		pr_crit("Invalid parameters for execmem allocator, module loading will fail");		return false;	} 	return true;} static void execmem_init_missing(struct execmem_info *info){	struct execmem_range *default_range = &info->ranges[EXECMEM_DEFAULT]; 	for (int i = EXECMEM_DEFAULT + 1; i < EXECMEM_TYPE_MAX; i++) {		struct execmem_range *r = &info->ranges[i]; 		if (!r->start) {			if (i == EXECMEM_MODULE_DATA)				r->pgprot = PAGE_KERNEL;			else				r->pgprot = default_range->pgprot;			r->alignment = default_range->alignment;			r->start = default_range->start;			r->end = default_range->end;			r->flags = default_range->flags;			r->fallback_start = default_range->fallback_start;			r->fallback_end = default_range->fallback_end;		}	}} struct execmem_info * __weak execmem_arch_setup(void){	return NULL;} static void __init __execmem_init(void){	struct execmem_info *info = execmem_arch_setup(); 	if (!info) {		info = execmem_info = &default_execmem_info;		info->ranges[EXECMEM_DEFAULT].start = VMALLOC_START;		info->ranges[EXECMEM_DEFAULT].end = VMALLOC_END;		info->ranges[EXECMEM_DEFAULT].pgprot = PAGE_KERNEL_EXEC;		info->ranges[EXECMEM_DEFAULT].alignment = 1;	} 	if (!execmem_validate(info))		return; 	execmem_init_missing(info); 	execmem_info = info;} #ifdef CONFIG_ARCH_WANTS_EXECMEM_LATEstatic int __init execmem_late_init(void){	__execmem_init();	return 0;}core_initcall(execmem_late_init);#elsevoid __init execmem_init(void){	__execmem_init();}#endif