forked from mirrors/linux
		
	An arch may want to tweak the mmap prot flags for an ELFexecutable's initial mappings. For example, arm64 is going to need to add PROT_BTI for executable pages in an ELF process whose executable is marked as using Branch Target Identification (an ARMv8.5-A control flow integrity feature). So that this can be done in a generic way, add a hook arch_elf_adjust_prot() to modify the prot flags as desired: arches can select CONFIG_HAVE_ELF_PROT and implement their own backend where necessary. By default, leave the prot flags unchanged. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
		
			
				
	
	
		
			102 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			102 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_ELF_H
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#define _LINUX_ELF_H
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#include <linux/types.h>
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#include <asm/elf.h>
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#include <uapi/linux/elf.h>
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#ifndef elf_read_implies_exec
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  /* Executables for which elf_read_implies_exec() returns TRUE will
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     have the READ_IMPLIES_EXEC personality flag set automatically.
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     Override in asm/elf.h as needed.  */
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# define elf_read_implies_exec(ex, have_pt_gnu_stack)	0
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#endif
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#ifndef SET_PERSONALITY
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#define SET_PERSONALITY(ex) \
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	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
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#endif
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#ifndef SET_PERSONALITY2
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#define SET_PERSONALITY2(ex, state) \
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	SET_PERSONALITY(ex)
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#endif
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#define ELF32_GNU_PROPERTY_ALIGN	4
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#define ELF64_GNU_PROPERTY_ALIGN	8
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#if ELF_CLASS == ELFCLASS32
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extern Elf32_Dyn _DYNAMIC [];
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#define elfhdr		elf32_hdr
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#define elf_phdr	elf32_phdr
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#define elf_shdr	elf32_shdr
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#define elf_note	elf32_note
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#define elf_addr_t	Elf32_Off
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#define Elf_Half	Elf32_Half
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#define Elf_Word	Elf32_Word
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#define ELF_GNU_PROPERTY_ALIGN	ELF32_GNU_PROPERTY_ALIGN
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#else
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extern Elf64_Dyn _DYNAMIC [];
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#define elfhdr		elf64_hdr
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#define elf_phdr	elf64_phdr
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#define elf_shdr	elf64_shdr
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#define elf_note	elf64_note
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#define elf_addr_t	Elf64_Off
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#define Elf_Half	Elf64_Half
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#define Elf_Word	Elf64_Word
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#define ELF_GNU_PROPERTY_ALIGN	ELF64_GNU_PROPERTY_ALIGN
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#endif
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/* Optional callbacks to write extra ELF notes. */
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struct file;
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struct coredump_params;
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#ifndef ARCH_HAVE_EXTRA_ELF_NOTES
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static inline int elf_coredump_extra_notes_size(void) { return 0; }
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static inline int elf_coredump_extra_notes_write(struct coredump_params *cprm) { return 0; }
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#else
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extern int elf_coredump_extra_notes_size(void);
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extern int elf_coredump_extra_notes_write(struct coredump_params *cprm);
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#endif
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/*
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 * NT_GNU_PROPERTY_TYPE_0 header:
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 * Keep this internal until/unless there is an agreed UAPI definition.
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 * pr_type values (GNU_PROPERTY_*) are public and defined in the UAPI header.
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 */
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struct gnu_property {
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	u32 pr_type;
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	u32 pr_datasz;
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};
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struct arch_elf_state;
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#ifndef CONFIG_ARCH_USE_GNU_PROPERTY
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static inline int arch_parse_elf_property(u32 type, const void *data,
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					  size_t datasz, bool compat,
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					  struct arch_elf_state *arch)
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{
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	return 0;
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}
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#else
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extern int arch_parse_elf_property(u32 type, const void *data, size_t datasz,
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				   bool compat, struct arch_elf_state *arch);
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#endif
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#ifdef CONFIG_ARCH_HAVE_ELF_PROT
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int arch_elf_adjust_prot(int prot, const struct arch_elf_state *state,
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			 bool has_interp, bool is_interp);
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#else
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static inline int arch_elf_adjust_prot(int prot,
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				       const struct arch_elf_state *state,
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				       bool has_interp, bool is_interp)
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{
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	return prot;
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}
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#endif
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#endif /* _LINUX_ELF_H */
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