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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/purgatory | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/purgatory')
-rw-r--r-- | arch/x86/purgatory/.gitignore | 1 | ||||
-rw-r--r-- | arch/x86/purgatory/Makefile | 91 | ||||
-rw-r--r-- | arch/x86/purgatory/entry64.S | 103 | ||||
-rw-r--r-- | arch/x86/purgatory/kexec-purgatory.S | 14 | ||||
-rw-r--r-- | arch/x86/purgatory/purgatory.c | 60 | ||||
-rw-r--r-- | arch/x86/purgatory/setup-x86_64.S | 59 | ||||
-rw-r--r-- | arch/x86/purgatory/stack.S | 18 |
7 files changed, 346 insertions, 0 deletions
diff --git a/arch/x86/purgatory/.gitignore b/arch/x86/purgatory/.gitignore new file mode 100644 index 0000000000..d2be150067 --- /dev/null +++ b/arch/x86/purgatory/.gitignore @@ -0,0 +1 @@ +purgatory.chk diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile new file mode 100644 index 0000000000..08aa0f25f1 --- /dev/null +++ b/arch/x86/purgatory/Makefile @@ -0,0 +1,91 @@ +# SPDX-License-Identifier: GPL-2.0 +OBJECT_FILES_NON_STANDARD := y + +purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o + +targets += $(purgatory-y) +PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) + +$(obj)/string.o: $(srctree)/arch/x86/boot/compressed/string.c FORCE + $(call if_changed_rule,cc_o_c) + +$(obj)/sha256.o: $(srctree)/lib/crypto/sha256.c FORCE + $(call if_changed_rule,cc_o_c) + +CFLAGS_sha256.o := -D__DISABLE_EXPORTS -D__NO_FORTIFY + +# When profile-guided optimization is enabled, llvm emits two different +# overlapping text sections, which is not supported by kexec. Remove profile +# optimization flags. +KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%,$(KBUILD_CFLAGS)) + +# When LTO is enabled, llvm emits many text sections, which is not supported +# by kexec. Remove -flto=* flags. +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS)) + +# When linking purgatory.ro with -r unresolved symbols are not checked, +# also link a purgatory.chk binary without -r to check for unresolved symbols. +PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib +LDFLAGS_purgatory.ro := -r $(PURGATORY_LDFLAGS) +LDFLAGS_purgatory.chk := $(PURGATORY_LDFLAGS) +targets += purgatory.ro purgatory.chk + +# Sanitizer, etc. runtimes are unavailable and cannot be linked here. +GCOV_PROFILE := n +KASAN_SANITIZE := n +UBSAN_SANITIZE := n +KCSAN_SANITIZE := n +KMSAN_SANITIZE := n +KCOV_INSTRUMENT := n + +# These are adjustments to the compiler flags used for objects that +# make up the standalone purgatory.ro + +PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel +PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss -g0 +PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING +PURGATORY_CFLAGS += -fno-stack-protector + +# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That +# in turn leaves some undefined symbols like __fentry__ in purgatory and not +# sure how to relocate those. +ifdef CONFIG_FUNCTION_TRACER +PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_FTRACE) +endif + +ifdef CONFIG_STACKPROTECTOR +PURGATORY_CFLAGS_REMOVE += -fstack-protector +endif + +ifdef CONFIG_STACKPROTECTOR_STRONG +PURGATORY_CFLAGS_REMOVE += -fstack-protector-strong +endif + +ifdef CONFIG_RETPOLINE +PURGATORY_CFLAGS_REMOVE += $(RETPOLINE_CFLAGS) +endif + +ifdef CONFIG_CFI_CLANG +PURGATORY_CFLAGS_REMOVE += $(CC_FLAGS_CFI) +endif + +CFLAGS_REMOVE_purgatory.o += $(PURGATORY_CFLAGS_REMOVE) +CFLAGS_purgatory.o += $(PURGATORY_CFLAGS) + +CFLAGS_REMOVE_sha256.o += $(PURGATORY_CFLAGS_REMOVE) +CFLAGS_sha256.o += $(PURGATORY_CFLAGS) + +CFLAGS_REMOVE_string.o += $(PURGATORY_CFLAGS_REMOVE) +CFLAGS_string.o += $(PURGATORY_CFLAGS) + +asflags-remove-y += $(foreach x, -g -gdwarf-4 -gdwarf-5, $(x) -Wa,$(x)) + +$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE + $(call if_changed,ld) + +$(obj)/purgatory.chk: $(obj)/purgatory.ro FORCE + $(call if_changed,ld) + +$(obj)/kexec-purgatory.o: $(obj)/purgatory.ro $(obj)/purgatory.chk + +obj-y += kexec-purgatory.o diff --git a/arch/x86/purgatory/entry64.S b/arch/x86/purgatory/entry64.S new file mode 100644 index 0000000000..0b4390ce58 --- /dev/null +++ b/arch/x86/purgatory/entry64.S @@ -0,0 +1,103 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com) + * Copyright (C) 2014 Red Hat Inc. + + * Author(s): Vivek Goyal <vgoyal@redhat.com> + * + * This code has been taken from kexec-tools. + */ + +#include <linux/linkage.h> + + .text + .balign 16 + .code64 + +SYM_CODE_START(entry64) + /* Setup a gdt that should be preserved */ + lgdt gdt(%rip) + + /* load the data segments */ + movl $0x18, %eax /* data segment */ + movl %eax, %ds + movl %eax, %es + movl %eax, %ss + movl %eax, %fs + movl %eax, %gs + + /* Setup new stack */ + leaq stack_init(%rip), %rsp + pushq $0x10 /* CS */ + leaq new_cs_exit(%rip), %rax + pushq %rax + lretq +new_cs_exit: + + /* Load the registers */ + movq rax(%rip), %rax + movq rbx(%rip), %rbx + movq rcx(%rip), %rcx + movq rdx(%rip), %rdx + movq rsi(%rip), %rsi + movq rdi(%rip), %rdi + movq rsp(%rip), %rsp + movq rbp(%rip), %rbp + movq r8(%rip), %r8 + movq r9(%rip), %r9 + movq r10(%rip), %r10 + movq r11(%rip), %r11 + movq r12(%rip), %r12 + movq r13(%rip), %r13 + movq r14(%rip), %r14 + movq r15(%rip), %r15 + + /* Jump to the new code... */ + jmpq *rip(%rip) +SYM_CODE_END(entry64) + + .section ".rodata" + .balign 4 +SYM_DATA_START(entry64_regs) +rax: .quad 0x0 +rcx: .quad 0x0 +rdx: .quad 0x0 +rbx: .quad 0x0 +rsp: .quad 0x0 +rbp: .quad 0x0 +rsi: .quad 0x0 +rdi: .quad 0x0 +r8: .quad 0x0 +r9: .quad 0x0 +r10: .quad 0x0 +r11: .quad 0x0 +r12: .quad 0x0 +r13: .quad 0x0 +r14: .quad 0x0 +r15: .quad 0x0 +rip: .quad 0x0 +SYM_DATA_END(entry64_regs) + + /* GDT */ + .section ".rodata" + .balign 16 +SYM_DATA_START_LOCAL(gdt) + /* + * 0x00 unusable segment + * 0x08 unused + * so use them as gdt ptr + */ + .word gdt_end - gdt - 1 + .quad gdt + .word 0, 0, 0 + + /* 0x10 4GB flat code segment */ + .word 0xFFFF, 0x0000, 0x9A00, 0x00AF + + /* 0x18 4GB flat data segment */ + .word 0xFFFF, 0x0000, 0x9200, 0x00CF +SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) + +SYM_DATA_START_LOCAL(stack) + .quad 0, 0 +SYM_DATA_END_LABEL(stack, SYM_L_LOCAL, stack_init) diff --git a/arch/x86/purgatory/kexec-purgatory.S b/arch/x86/purgatory/kexec-purgatory.S new file mode 100644 index 0000000000..8530fe93b7 --- /dev/null +++ b/arch/x86/purgatory/kexec-purgatory.S @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + + .section .rodata, "a" + + .align 8 +kexec_purgatory: + .globl kexec_purgatory + .incbin "arch/x86/purgatory/purgatory.ro" +.Lkexec_purgatory_end: + + .align 8 +kexec_purgatory_size: + .globl kexec_purgatory_size + .quad .Lkexec_purgatory_end - kexec_purgatory diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c new file mode 100644 index 0000000000..aea47e7939 --- /dev/null +++ b/arch/x86/purgatory/purgatory.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * purgatory: Runs between two kernels + * + * Copyright (C) 2014 Red Hat Inc. + * + * Author: + * Vivek Goyal <vgoyal@redhat.com> + */ + +#include <linux/bug.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <crypto/sha2.h> +#include <asm/purgatory.h> + +#include "../boot/compressed/error.h" +#include "../boot/string.h" + +u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(".kexec-purgatory"); + +struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(".kexec-purgatory"); + +static int verify_sha256_digest(void) +{ + struct kexec_sha_region *ptr, *end; + u8 digest[SHA256_DIGEST_SIZE]; + struct sha256_state sctx; + + sha256_init(&sctx); + end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions); + + for (ptr = purgatory_sha_regions; ptr < end; ptr++) + sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len); + + sha256_final(&sctx, digest); + + if (memcmp(digest, purgatory_sha256_digest, sizeof(digest))) + return 1; + + return 0; +} + +void purgatory(void) +{ + int ret; + + ret = verify_sha256_digest(); + if (ret) { + /* loop forever */ + for (;;) + ; + } +} + +/* + * Defined in order to reuse memcpy() and memset() from + * arch/x86/boot/compressed/string.c + */ +void warn(const char *msg) {} diff --git a/arch/x86/purgatory/setup-x86_64.S b/arch/x86/purgatory/setup-x86_64.S new file mode 100644 index 0000000000..89d9e9e53f --- /dev/null +++ b/arch/x86/purgatory/setup-x86_64.S @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * purgatory: setup code + * + * Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com) + * Copyright (C) 2014 Red Hat Inc. + * + * This code has been taken from kexec-tools. + */ +#include <linux/linkage.h> +#include <asm/purgatory.h> + + .text + .balign 16 + .code64 + +SYM_CODE_START(purgatory_start) + /* Load a gdt so I know what the segment registers are */ + lgdt gdt(%rip) + + /* load the data segments */ + movl $0x18, %eax /* data segment */ + movl %eax, %ds + movl %eax, %es + movl %eax, %ss + movl %eax, %fs + movl %eax, %gs + + /* Setup a stack */ + leaq lstack_end(%rip), %rsp + + /* Call the C code */ + call purgatory + jmp entry64 +SYM_CODE_END(purgatory_start) + + .section ".rodata" + .balign 16 +SYM_DATA_START_LOCAL(gdt) + /* 0x00 unusable segment + * 0x08 unused + * so use them as the gdt ptr + */ + .word gdt_end - gdt - 1 + .quad gdt + .word 0, 0, 0 + + /* 0x10 4GB flat code segment */ + .word 0xFFFF, 0x0000, 0x9A00, 0x00AF + + /* 0x18 4GB flat data segment */ + .word 0xFFFF, 0x0000, 0x9200, 0x00CF +SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) + + .bss + .balign 4096 +SYM_DATA_START_LOCAL(lstack) + .skip 4096 +SYM_DATA_END_LABEL(lstack, SYM_L_LOCAL, lstack_end) diff --git a/arch/x86/purgatory/stack.S b/arch/x86/purgatory/stack.S new file mode 100644 index 0000000000..1ef507ca50 --- /dev/null +++ b/arch/x86/purgatory/stack.S @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * purgatory: stack + * + * Copyright (C) 2014 Red Hat Inc. + */ + +#include <linux/linkage.h> + + /* A stack for the loaded kernel. + * Separate and in the data section so it can be prepopulated. + */ + .data + .balign 4096 + +SYM_DATA_START(stack) + .skip 4096 +SYM_DATA_END_LABEL(stack, SYM_L_GLOBAL, stack_end) |