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Commit ac248a8b authored by Mark Brown's avatar Mark Brown
Browse files

Merge remote-tracking branch 'lsk/v4.4/topic/mm-kaslr' into linux-linaro-lsk-v4.4

parents bd06e78b 5808d4c6

arch/arm64/Kconfig.debug

+1 −1
Original line number Diff line number Diff line
@@ -73,7 +73,7 @@ config DEBUG_RODATA 
          If in doubt, say Y



config DEBUG_ALIGN_RODATA

	depends on DEBUG_RODATA && ARM64_4K_PAGES

	depends on DEBUG_RODATA

	bool "Align linker sections up to SECTION_SIZE"

	help

	  If this option is enabled, sections that may potentially be marked as

arch/arm64/include/asm/assembler.h

+20 −0
Original line number Diff line number Diff line
@@ -233,4 +233,24 @@ lr .req x30 // link register 
	.long	\sym\()_hi32

	.endm



	/*

	 * mov_q - move an immediate constant into a 64-bit register using

	 *         between 2 and 4 movz/movk instructions (depending on the

	 *         magnitude and sign of the operand)

	 */

	.macro	mov_q, reg, val

	.if (((\val) >> 31) == 0 || ((\val) >> 31) == 0x1ffffffff)

	movz	\reg, :abs_g1_s:\val

	.else

	.if (((\val) >> 47) == 0 || ((\val) >> 47) == 0x1ffff)

	movz	\reg, :abs_g2_s:\val

	.else

	movz	\reg, :abs_g3:\val

	movk	\reg, :abs_g2_nc:\val

	.endif

	movk	\reg, :abs_g1_nc:\val

	.endif

	movk	\reg, :abs_g0_nc:\val

	.endm



#endif	/* __ASM_ASSEMBLER_H */

arch/arm64/kernel/efi-entry.S

+1 −1
Original line number Diff line number Diff line
@@ -61,7 +61,7 @@ ENTRY(entry) 
	 */

	mov	x20, x0		// DTB address

	ldr	x0, [sp, #16]	// relocated _text address

	movz	x21, #:abs_g0:stext_offset

	ldr	w21, =stext_offset

	add	x21, x0, x21



	/*

arch/arm64/kernel/head.S

+84 −76
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/irqchip/arm-gic-v3.h>



#include <asm/assembler.h>

#include <asm/boot.h>

#include <asm/ptrace.h>

#include <asm/asm-offsets.h>

#include <asm/cache.h>
@@ -100,8 +101,6 @@ _head: 
#endif



#ifdef CONFIG_EFI

	.globl	__efistub_stext_offset

	.set	__efistub_stext_offset, stext - _head

	.align 3

pe_header:

	.ascii	"PE"
@@ -121,11 +120,11 @@ optional_header: 
	.short	0x20b				// PE32+ format

	.byte	0x02				// MajorLinkerVersion

	.byte	0x14				// MinorLinkerVersion

	.long	_end - stext			// SizeOfCode

	.long	_end - efi_header_end		// SizeOfCode

	.long	0				// SizeOfInitializedData

	.long	0				// SizeOfUninitializedData

	.long	__efistub_entry - _head		// AddressOfEntryPoint

	.long	__efistub_stext_offset		// BaseOfCode

	.long	efi_header_end - _head		// BaseOfCode



extra_header_fields:

	.quad	0				// ImageBase
@@ -142,7 +141,7 @@ extra_header_fields: 
	.long	_end - _head			// SizeOfImage



	// Everything before the kernel image is considered part of the header

	.long	__efistub_stext_offset		// SizeOfHeaders

	.long	efi_header_end - _head		// SizeOfHeaders

	.long	0				// CheckSum

	.short	0xa				// Subsystem (EFI application)

	.short	0				// DllCharacteristics
@@ -186,10 +185,10 @@ section_table: 
	.byte	0

	.byte	0

	.byte	0        		// end of 0 padding of section name

	.long	_end - stext		// VirtualSize

	.long	__efistub_stext_offset	// VirtualAddress

	.long	_edata - stext		// SizeOfRawData

	.long	__efistub_stext_offset	// PointerToRawData

	.long	_end - efi_header_end	// VirtualSize

	.long	efi_header_end - _head	// VirtualAddress

	.long	_edata - efi_header_end	// SizeOfRawData

	.long	efi_header_end - _head	// PointerToRawData



	.long	0		// PointerToRelocations (0 for executables)

	.long	0		// PointerToLineNumbers (0 for executables)
@@ -198,20 +197,23 @@ section_table: 
	.long	0xe0500020	// Characteristics (section flags)



	/*

	 * EFI will load stext onwards at the 4k section alignment

	 * EFI will load .text onwards at the 4k section alignment

	 * described in the PE/COFF header. To ensure that instruction

	 * sequences using an adrp and a :lo12: immediate will function

	 * correctly at this alignment, we must ensure that stext is

	 * correctly at this alignment, we must ensure that .text is

	 * placed at a 4k boundary in the Image to begin with.

	 */

	.align 12

efi_header_end:

#endif



	__INIT



ENTRY(stext)

	bl	preserve_boot_args

	bl	el2_setup			// Drop to EL1, w20=cpu_boot_mode

	mov	x23, xzr			// KASLR offset, defaults to 0

	adrp	x24, __PHYS_OFFSET

	and	x23, x24, MIN_KIMG_ALIGN - 1	// KASLR offset, defaults to 0

	bl	set_cpu_boot_mode_flag

	bl	__create_page_tables		// x25=TTBR0, x26=TTBR1

	/*
@@ -220,13 +222,11 @@ ENTRY(stext) 
	 * On return, the CPU will be ready for the MMU to be turned on and

	 * the TCR will have been set.

	 */

	ldr	x27, 0f				// address to jump to after

	bl	__cpu_setup			// initialise processor

	adr_l	x27, __primary_switch		// address to jump to after

						// MMU has been enabled

	adr_l	lr, __enable_mmu		// return (PIC) address

	b	__cpu_setup			// initialise processor

	b	__enable_mmu

ENDPROC(stext)

	.align	3

0:	.quad	__mmap_switched - (_head - TEXT_OFFSET) + KIMAGE_VADDR



/*

 * Preserve the arguments passed by the bootloader in x0 .. x3
@@ -336,7 +336,7 @@ __create_page_tables: 
	cmp	x0, x6

	b.lo	1b



	ldr	x7, =SWAPPER_MM_MMUFLAGS

	mov	x7, SWAPPER_MM_MMUFLAGS



	/*

	 * Create the identity mapping.
@@ -392,12 +392,13 @@ __create_page_tables: 
	 * Map the kernel image (starting with PHYS_OFFSET).

	 */

	mov	x0, x26				// swapper_pg_dir

	ldr	x5, =KIMAGE_VADDR

	mov_q	x5, KIMAGE_VADDR + TEXT_OFFSET	// compile time __va(_text)

	add	x5, x5, x23			// add KASLR displacement

	create_pgd_entry x0, x5, x3, x6

	ldr	w6, kernel_img_size

	add	x6, x6, x5

	mov	x3, x24				// phys offset

	adrp	x6, _end			// runtime __pa(_end)

	adrp	x3, _text			// runtime __pa(_text)

	sub	x6, x6, x3			// _end - _text

	add	x6, x6, x5			// runtime __va(_end)

	create_block_map x0, x7, x3, x5, x6



	/*
@@ -412,16 +413,13 @@ __create_page_tables: 


	ret	x28

ENDPROC(__create_page_tables)



kernel_img_size:

	.long	_end - (_head - TEXT_OFFSET)

	.ltorg



/*

 * The following fragment of code is executed with the MMU enabled.

 */

	.set	initial_sp, init_thread_union + THREAD_START_SP

__mmap_switched:

__primary_switched:

	mov	x28, lr				// preserve LR

	adr_l	x8, vectors			// load VBAR_EL1 with virtual

	msr	vbar_el1, x8			// vector table address
@@ -435,44 +433,6 @@ __mmap_switched: 
	bl	__pi_memset

	dsb	ishst				// Make zero page visible to PTW



#ifdef CONFIG_RELOCATABLE



	/*

	 * Iterate over each entry in the relocation table, and apply the

	 * relocations in place.

	 */

	adr_l	x8, __dynsym_start		// start of symbol table

	adr_l	x9, __reloc_start		// start of reloc table

	adr_l	x10, __reloc_end		// end of reloc table



0:	cmp	x9, x10

	b.hs	2f

	ldp	x11, x12, [x9], #24

	ldr	x13, [x9, #-8]

	cmp	w12, #R_AARCH64_RELATIVE

	b.ne	1f

	add	x13, x13, x23			// relocate

	str	x13, [x11, x23]

	b	0b



1:	cmp	w12, #R_AARCH64_ABS64

	b.ne	0b

	add	x12, x12, x12, lsl #1		// symtab offset: 24x top word

	add	x12, x8, x12, lsr #(32 - 3)	// ... shifted into bottom word

	ldrsh	w14, [x12, #6]			// Elf64_Sym::st_shndx

	ldr	x15, [x12, #8]			// Elf64_Sym::st_value

	cmp	w14, #-0xf			// SHN_ABS (0xfff1) ?

	add	x14, x15, x23			// relocate

	csel	x15, x14, x15, ne

	add	x15, x13, x15

	str	x15, [x11, x23]

	b	0b



2:	adr_l	x8, kimage_vaddr		// make relocated kimage_vaddr

	dc	cvac, x8			// value visible to secondaries

	dsb	sy				// with MMU off

#endif



	adr_l	sp, initial_sp, x4

	mov	x4, sp

	and	x4, x4, #~(THREAD_SIZE - 1)
@@ -488,17 +448,19 @@ __mmap_switched: 
	bl	kasan_early_init

#endif

#ifdef CONFIG_RANDOMIZE_BASE

	cbnz	x23, 0f				// already running randomized?

	tst	x23, ~(MIN_KIMG_ALIGN - 1)	// already running randomized?

	b.ne	0f

	mov	x0, x21				// pass FDT address in x0

	mov	x1, x23				// pass modulo offset in x1

	bl	kaslr_early_init		// parse FDT for KASLR options

	cbz	x0, 0f				// KASLR disabled? just proceed

	mov	x23, x0				// record KASLR offset

	orr	x23, x23, x0			// record KASLR offset

	ret	x28				// we must enable KASLR, return

						// to __enable_mmu()

0:

#endif

	b	start_kernel

ENDPROC(__mmap_switched)

ENDPROC(__primary_switched)



/*

 * end early head section, begin head code that is also used for
@@ -613,7 +575,7 @@ ENDPROC(el2_setup) 
 * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed

 * in x20. See arch/arm64/include/asm/virt.h for more info.

 */

ENTRY(set_cpu_boot_mode_flag)

set_cpu_boot_mode_flag:

	adr_l	x1, __boot_cpu_mode

	cmp	w20, #BOOT_CPU_MODE_EL2

	b.ne	1f
@@ -646,7 +608,7 @@ ENTRY(secondary_holding_pen) 
	bl	el2_setup			// Drop to EL1, w20=cpu_boot_mode

	bl	set_cpu_boot_mode_flag

	mrs	x0, mpidr_el1

	ldr     x1, =MPIDR_HWID_BITMASK

	mov_q	x1, MPIDR_HWID_BITMASK

	and	x0, x0, x1

	adr_l	x3, secondary_holding_pen_release

pen:	ldr	x4, [x3]
@@ -666,7 +628,7 @@ ENTRY(secondary_entry) 
	b	secondary_startup

ENDPROC(secondary_entry)



ENTRY(secondary_startup)

secondary_startup:

	/*

	 * Common entry point for secondary CPUs.

	 */
@@ -674,14 +636,11 @@ ENTRY(secondary_startup) 
	adrp	x26, swapper_pg_dir

	bl	__cpu_setup			// initialise processor



	ldr	x8, kimage_vaddr

	ldr	w9, 0f

	sub	x27, x8, w9, sxtw		// address to jump to after enabling the MMU

	adr_l	x27, __secondary_switch		// address to jump to after enabling the MMU

	b	__enable_mmu

ENDPROC(secondary_startup)

0:	.long	(_text - TEXT_OFFSET) - __secondary_switched



ENTRY(__secondary_switched)

__secondary_switched:

	adr_l	x5, vectors

	msr	vbar_el1, x5

	isb
@@ -743,7 +702,6 @@ __enable_mmu: 
	ic	iallu				// flush instructions fetched

	dsb	nsh				// via old mapping

	isb

	add	x27, x27, x23			// relocated __mmap_switched

#endif

	br	x27

ENDPROC(__enable_mmu)
@@ -752,3 +710,53 @@ __no_granule_support: 
	wfe

	b __no_granule_support

ENDPROC(__no_granule_support)



__primary_switch:

#ifdef CONFIG_RELOCATABLE

	/*

	 * Iterate over each entry in the relocation table, and apply the

	 * relocations in place.

	 */

	ldr	w8, =__dynsym_offset		// offset to symbol table

	ldr	w9, =__rela_offset		// offset to reloc table

	ldr	w10, =__rela_size		// size of reloc table



	mov_q	x11, KIMAGE_VADDR		// default virtual offset

	add	x11, x11, x23			// actual virtual offset

	add	x8, x8, x11			// __va(.dynsym)

	add	x9, x9, x11			// __va(.rela)

	add	x10, x9, x10			// __va(.rela) + sizeof(.rela)



0:	cmp	x9, x10

	b.hs	2f

	ldp	x11, x12, [x9], #24

	ldr	x13, [x9, #-8]

	cmp	w12, #R_AARCH64_RELATIVE

	b.ne	1f

	add	x13, x13, x23			// relocate

	str	x13, [x11, x23]

	b	0b



1:	cmp	w12, #R_AARCH64_ABS64

	b.ne	0b

	add	x12, x12, x12, lsl #1		// symtab offset: 24x top word

	add	x12, x8, x12, lsr #(32 - 3)	// ... shifted into bottom word

	ldrsh	w14, [x12, #6]			// Elf64_Sym::st_shndx

	ldr	x15, [x12, #8]			// Elf64_Sym::st_value

	cmp	w14, #-0xf			// SHN_ABS (0xfff1) ?

	add	x14, x15, x23			// relocate

	csel	x15, x14, x15, ne

	add	x15, x13, x15

	str	x15, [x11, x23]

	b	0b



2:

#endif

	ldr	x8, =__primary_switched

	br	x8

ENDPROC(__primary_switch)



__secondary_switch:

	ldr	x8, =__secondary_switched

	br	x8

ENDPROC(__secondary_switch)

arch/arm64/kernel/image.h

+2 −0
Original line number Diff line number Diff line
@@ -73,6 +73,8 @@ 


#ifdef CONFIG_EFI



__efistub_stext_offset = stext - _text;



/*

 * Prevent the symbol aliases below from being emitted into the kallsyms

 * table, by forcing them to be absolute symbols (which are conveniently