Commit:e2b32e6785("x86, kaslr: randomize module base load address") made module base address randomization unconditional and didn't regard disabled KKASLR due to CONFIG_HIBERNATION and command line option "nokaslr". For more info see (now reverted) commit:f47233c2d3("x86/mm/ASLR: Propagate base load address calculation") In order to propagate KASLR status to kernel proper, we need a single bit in boot_params.hdr.loadflags and we've chosen bit 1 thus leaving the top-down allocated bits for bits supposed to be used by the bootloader. Originally-From: Jiri Kosina <jkosina@suse.cz> Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
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#ifndef _ASM_X86_BOOTPARAM_H
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#define _ASM_X86_BOOTPARAM_H
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/* setup_data types */
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#define SETUP_NONE			0
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#define SETUP_E820_EXT			1
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#define SETUP_DTB			2
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#define SETUP_PCI			3
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#define SETUP_EFI			4
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/* ram_size flags */
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#define RAMDISK_IMAGE_START_MASK	0x07FF
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#define RAMDISK_PROMPT_FLAG		0x8000
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#define RAMDISK_LOAD_FLAG		0x4000
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/* loadflags */
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#define LOADED_HIGH	(1<<0)
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#define KASLR_FLAG	(1<<1)
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#define QUIET_FLAG	(1<<5)
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#define KEEP_SEGMENTS	(1<<6)
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#define CAN_USE_HEAP	(1<<7)
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/* xloadflags */
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#define XLF_KERNEL_64			(1<<0)
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#define XLF_CAN_BE_LOADED_ABOVE_4G	(1<<1)
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#define XLF_EFI_HANDOVER_32		(1<<2)
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#define XLF_EFI_HANDOVER_64		(1<<3)
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#define XLF_EFI_KEXEC			(1<<4)
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#ifndef __ASSEMBLY__
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#include <linux/types.h>
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#include <linux/screen_info.h>
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#include <linux/apm_bios.h>
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#include <linux/edd.h>
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#include <asm/e820.h>
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#include <asm/ist.h>
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#include <video/edid.h>
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/* extensible setup data list node */
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struct setup_data {
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	__u64 next;
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	__u32 type;
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	__u32 len;
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	__u8 data[0];
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};
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struct setup_header {
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	__u8	setup_sects;
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	__u16	root_flags;
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	__u32	syssize;
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	__u16	ram_size;
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	__u16	vid_mode;
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	__u16	root_dev;
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	__u16	boot_flag;
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	__u16	jump;
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	__u32	header;
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	__u16	version;
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	__u32	realmode_swtch;
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	__u16	start_sys;
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	__u16	kernel_version;
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	__u8	type_of_loader;
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	__u8	loadflags;
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	__u16	setup_move_size;
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	__u32	code32_start;
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	__u32	ramdisk_image;
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	__u32	ramdisk_size;
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	__u32	bootsect_kludge;
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	__u16	heap_end_ptr;
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	__u8	ext_loader_ver;
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	__u8	ext_loader_type;
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	__u32	cmd_line_ptr;
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	__u32	initrd_addr_max;
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	__u32	kernel_alignment;
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	__u8	relocatable_kernel;
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	__u8	min_alignment;
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	__u16	xloadflags;
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	__u32	cmdline_size;
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	__u32	hardware_subarch;
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	__u64	hardware_subarch_data;
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	__u32	payload_offset;
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	__u32	payload_length;
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	__u64	setup_data;
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	__u64	pref_address;
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	__u32	init_size;
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	__u32	handover_offset;
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} __attribute__((packed));
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struct sys_desc_table {
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	__u16 length;
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	__u8  table[14];
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};
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/* Gleaned from OFW's set-parameters in cpu/x86/pc/linux.fth */
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struct olpc_ofw_header {
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	__u32 ofw_magic;	/* OFW signature */
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	__u32 ofw_version;
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	__u32 cif_handler;	/* callback into OFW */
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	__u32 irq_desc_table;
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} __attribute__((packed));
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struct efi_info {
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	__u32 efi_loader_signature;
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	__u32 efi_systab;
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	__u32 efi_memdesc_size;
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	__u32 efi_memdesc_version;
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	__u32 efi_memmap;
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	__u32 efi_memmap_size;
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	__u32 efi_systab_hi;
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	__u32 efi_memmap_hi;
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};
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/* The so-called "zeropage" */
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struct boot_params {
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	struct screen_info screen_info;			/* 0x000 */
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	struct apm_bios_info apm_bios_info;		/* 0x040 */
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	__u8  _pad2[4];					/* 0x054 */
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	__u64  tboot_addr;				/* 0x058 */
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	struct ist_info ist_info;			/* 0x060 */
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	__u8  _pad3[16];				/* 0x070 */
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	__u8  hd0_info[16];	/* obsolete! */		/* 0x080 */
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	__u8  hd1_info[16];	/* obsolete! */		/* 0x090 */
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	struct sys_desc_table sys_desc_table;		/* 0x0a0 */
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	struct olpc_ofw_header olpc_ofw_header;		/* 0x0b0 */
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	__u32 ext_ramdisk_image;			/* 0x0c0 */
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	__u32 ext_ramdisk_size;				/* 0x0c4 */
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	__u32 ext_cmd_line_ptr;				/* 0x0c8 */
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	__u8  _pad4[116];				/* 0x0cc */
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	struct edid_info edid_info;			/* 0x140 */
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	struct efi_info efi_info;			/* 0x1c0 */
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	__u32 alt_mem_k;				/* 0x1e0 */
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	__u32 scratch;		/* Scratch field! */	/* 0x1e4 */
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	__u8  e820_entries;				/* 0x1e8 */
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	__u8  eddbuf_entries;				/* 0x1e9 */
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	__u8  edd_mbr_sig_buf_entries;			/* 0x1ea */
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	__u8  kbd_status;				/* 0x1eb */
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	__u8  _pad5[3];					/* 0x1ec */
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	/*
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	 * The sentinel is set to a nonzero value (0xff) in header.S.
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	 *
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	 * A bootloader is supposed to only take setup_header and put
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	 * it into a clean boot_params buffer. If it turns out that
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	 * it is clumsy or too generous with the buffer, it most
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	 * probably will pick up the sentinel variable too. The fact
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	 * that this variable then is still 0xff will let kernel
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	 * know that some variables in boot_params are invalid and
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	 * kernel should zero out certain portions of boot_params.
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	 */
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	__u8  sentinel;					/* 0x1ef */
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	__u8  _pad6[1];					/* 0x1f0 */
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	struct setup_header hdr;    /* setup header */	/* 0x1f1 */
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	__u8  _pad7[0x290-0x1f1-sizeof(struct setup_header)];
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	__u32 edd_mbr_sig_buffer[EDD_MBR_SIG_MAX];	/* 0x290 */
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	struct e820entry e820_map[E820MAX];		/* 0x2d0 */
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	__u8  _pad8[48];				/* 0xcd0 */
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	struct edd_info eddbuf[EDDMAXNR];		/* 0xd00 */
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	__u8  _pad9[276];				/* 0xeec */
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} __attribute__((packed));
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enum {
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	X86_SUBARCH_PC = 0,
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	X86_SUBARCH_LGUEST,
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	X86_SUBARCH_XEN,
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	X86_SUBARCH_INTEL_MID,
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	X86_SUBARCH_CE4100,
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	X86_NR_SUBARCHS,
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};
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#endif /* __ASSEMBLY__ */
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#endif /* _ASM_X86_BOOTPARAM_H */
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