133 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			133 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_EXECMEM_ALLOC_H
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| #define _LINUX_EXECMEM_ALLOC_H
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| 
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| #include <linux/types.h>
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| #include <linux/moduleloader.h>
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| 
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| #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
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| 		!defined(CONFIG_KASAN_VMALLOC)
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| #include <linux/kasan.h>
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| #define MODULE_ALIGN (PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT)
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| #else
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| #define MODULE_ALIGN PAGE_SIZE
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| #endif
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| 
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| /**
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|  * enum execmem_type - types of executable memory ranges
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|  *
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|  * There are several subsystems that allocate executable memory.
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|  * Architectures define different restrictions on placement,
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|  * permissions, alignment and other parameters for memory that can be used
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|  * by these subsystems.
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|  * Types in this enum identify subsystems that allocate executable memory
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|  * and let architectures define parameters for ranges suitable for
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|  * allocations by each subsystem.
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|  *
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|  * @EXECMEM_DEFAULT: default parameters that would be used for types that
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|  * are not explicitly defined.
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|  * @EXECMEM_MODULE_TEXT: parameters for module text sections
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|  * @EXECMEM_KPROBES: parameters for kprobes
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|  * @EXECMEM_FTRACE: parameters for ftrace
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|  * @EXECMEM_BPF: parameters for BPF
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|  * @EXECMEM_MODULE_DATA: parameters for module data sections
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|  * @EXECMEM_TYPE_MAX:
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|  */
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| enum execmem_type {
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| 	EXECMEM_DEFAULT,
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| 	EXECMEM_MODULE_TEXT = EXECMEM_DEFAULT,
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| 	EXECMEM_KPROBES,
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| 	EXECMEM_FTRACE,
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| 	EXECMEM_BPF,
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| 	EXECMEM_MODULE_DATA,
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| 	EXECMEM_TYPE_MAX,
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| };
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| 
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| /**
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|  * enum execmem_range_flags - options for executable memory allocations
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|  * @EXECMEM_KASAN_SHADOW:	allocate kasan shadow
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|  */
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| enum execmem_range_flags {
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| 	EXECMEM_KASAN_SHADOW	= (1 << 0),
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| };
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| 
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| /**
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|  * struct execmem_range - definition of an address space suitable for code and
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|  *			  related data allocations
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|  * @start:	address space start
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|  * @end:	address space end (inclusive)
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|  * @fallback_start: start of the secondary address space range for fallback
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|  *                  allocations on architectures that require it
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|  * @fallback_end:   start of the secondary address space (inclusive)
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|  * @pgprot:	permissions for memory in this address space
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|  * @alignment:	alignment required for text allocations
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|  * @flags:	options for memory allocations for this range
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|  */
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| struct execmem_range {
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| 	unsigned long   start;
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| 	unsigned long   end;
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| 	unsigned long   fallback_start;
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| 	unsigned long   fallback_end;
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| 	pgprot_t        pgprot;
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| 	unsigned int	alignment;
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| 	enum execmem_range_flags flags;
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| };
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| 
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| /**
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|  * struct execmem_info - architecture parameters for code allocations
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|  * @ranges: array of parameter sets defining architecture specific
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|  * parameters for executable memory allocations. The ranges that are not
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|  * explicitly initialized by an architecture use parameters defined for
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|  * @EXECMEM_DEFAULT.
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|  */
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| struct execmem_info {
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| 	struct execmem_range	ranges[EXECMEM_TYPE_MAX];
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| };
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| 
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| /**
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|  * execmem_arch_setup - define parameters for allocations of executable memory
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|  *
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|  * A hook for architectures to define parameters for allocations of
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|  * executable memory. These parameters should be filled into the
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|  * @execmem_info structure.
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|  *
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|  * For architectures that do not implement this method a default set of
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|  * parameters will be used
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|  *
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|  * Return: a structure defining architecture parameters and restrictions
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|  * for allocations of executable memory
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|  */
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| struct execmem_info *execmem_arch_setup(void);
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| 
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| /**
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|  * execmem_alloc - allocate executable memory
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|  * @type: type of the allocation
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|  * @size: how many bytes of memory are required
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|  *
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|  * Allocates memory that will contain executable code, either generated or
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|  * loaded from kernel modules.
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|  *
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|  * Allocates memory that will contain data coupled with executable code,
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|  * like data sections in kernel modules.
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|  *
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|  * The memory will have protections defined by architecture for executable
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|  * region of the @type.
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|  *
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|  * Return: a pointer to the allocated memory or %NULL
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|  */
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| void *execmem_alloc(enum execmem_type type, size_t size);
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| 
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| /**
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|  * execmem_free - free executable memory
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|  * @ptr: pointer to the memory that should be freed
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|  */
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| void execmem_free(void *ptr);
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| 
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| #if defined(CONFIG_EXECMEM) && !defined(CONFIG_ARCH_WANTS_EXECMEM_LATE)
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| void execmem_init(void);
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| #else
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| static inline void execmem_init(void) {}
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| #endif
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| 
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| #endif /* _LINUX_EXECMEM_ALLOC_H */
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