From 2965faa5e03d1e71e9ff9aa143fff39e0a77543a Mon Sep 17 00:00:00 2001 From: Dave Young Date: Wed, 9 Sep 2015 15:38:55 -0700 Subject: kexec: split kexec_load syscall from kexec core code There are two kexec load syscalls, kexec_load another and kexec_file_load. kexec_file_load has been splited as kernel/kexec_file.c. In this patch I split kexec_load syscall code to kernel/kexec.c. And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and use kexec_file_load only, or vice verse. The original requirement is from Ted Ts'o, he want kexec kernel signature being checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use kexec_load syscall can bypass the checking. Vivek Goyal proposed to create a common kconfig option so user can compile in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects KEXEC_CORE so that old config files still work. Because there's general code need CONFIG_KEXEC_CORE, so I updated all the architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects KEXEC_CORE in arch Kconfig. Also updated general kernel code with to kexec_load syscall. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Dave Young Cc: Eric W. Biederman Cc: Vivek Goyal Cc: Petr Tesarik Cc: Theodore Ts'o Cc: Josh Boyer Cc: David Howells Cc: Geert Uytterhoeven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/firmware/efi/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 54071c148340..84533e02fbf8 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -43,7 +43,7 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE config EFI_RUNTIME_MAP bool "Export efi runtime maps to sysfs" - depends on X86 && EFI && KEXEC + depends on X86 && EFI && KEXEC_CORE default y help Export efi runtime memory maps to /sys/firmware/efi/runtime-map. -- cgit From 769a8089c1fd2fe94c13e66fe6e03d7820953ee3 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin Date: Tue, 22 Sep 2015 14:59:17 -0700 Subject: x86, efi, kasan: #undef memset/memcpy/memmove per arch In not-instrumented code KASAN replaces instrumented memset/memcpy/memmove with not-instrumented analogues __memset/__memcpy/__memove. However, on x86 the EFI stub is not linked with the kernel. It uses not-instrumented mem*() functions from arch/x86/boot/compressed/string.c So we don't replace them with __mem*() variants in EFI stub. On ARM64 the EFI stub is linked with the kernel, so we should replace mem*() functions with __mem*(), because the EFI stub runs before KASAN sets up early shadow. So let's move these #undef mem* into arch's asm/efi.h which is also included by the EFI stub. Also, this will fix the warning in 32-bit build reported by kbuild test robot: efi-stub-helper.c:599:2: warning: implicit declaration of function 'memcpy' [akpm@linux-foundation.org: use 80 cols in comment] Signed-off-by: Andrey Ryabinin Reported-by: Fengguang Wu Cc: Will Deacon Cc: Catalin Marinas Cc: Matt Fleming Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/firmware/efi/libstub/efistub.h | 4 ---- 1 file changed, 4 deletions(-) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index e334a01cf92f..6b6548fda089 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -5,10 +5,6 @@ /* error code which can't be mistaken for valid address */ #define EFI_ERROR (~0UL) -#undef memcpy -#undef memset -#undef memmove - void efi_char16_printk(efi_system_table_t *, efi_char16_t *); efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image, -- cgit From 0ce3cc008ec04258b6a6314b09f1a6012810881a Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 25 Sep 2015 23:02:19 +0100 Subject: arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regions The new Properties Table feature introduced in UEFIv2.5 may split memory regions that cover PE/COFF memory images into separate code and data regions. Since these regions only differ in the type (runtime code vs runtime data) and the permission bits, but not in the memory type attributes (UC/WC/WT/WB), the spec does not require them to be aligned to 64 KB. Since the relative offset of PE/COFF .text and .data segments cannot be changed on the fly, this means that we can no longer pad out those regions to be mappable using 64 KB pages. Unfortunately, there is no annotation in the UEFI memory map that identifies data regions that were split off from a code region, so we must apply this logic to all adjacent runtime regions whose attributes only differ in the permission bits. So instead of rounding each memory region to 64 KB alignment at both ends, only round down regions that are not directly preceded by another runtime region with the same type attributes. Since the UEFI spec does not mandate that the memory map be sorted, this means we also need to sort it first. Note that this change will result in all EFI_MEMORY_RUNTIME regions whose start addresses are not aligned to the OS page size to be mapped with executable permissions (i.e., on kernels compiled with 64 KB pages). However, since these mappings are only active during the time that UEFI Runtime Services are being invoked, the window for abuse is rather small. Tested-by: Mark Salter Tested-by: Mark Rutland [UEFI 2.4 only] Signed-off-by: Ard Biesheuvel Signed-off-by: Matt Fleming Reviewed-by: Mark Salter Reviewed-by: Mark Rutland Cc: # v4.0+ Cc: Catalin Marinas Cc: Leif Lindholm Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar --- drivers/firmware/efi/libstub/arm-stub.c | 88 +++++++++++++++++++++++++++------ 1 file changed, 73 insertions(+), 15 deletions(-) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index e29560e6b40b..950c87f5d279 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -13,6 +13,7 @@ */ #include +#include #include #include "efistub.h" @@ -305,6 +306,44 @@ fail: */ #define EFI_RT_VIRTUAL_BASE 0x40000000 +static int cmp_mem_desc(const void *l, const void *r) +{ + const efi_memory_desc_t *left = l, *right = r; + + return (left->phys_addr > right->phys_addr) ? 1 : -1; +} + +/* + * Returns whether region @left ends exactly where region @right starts, + * or false if either argument is NULL. + */ +static bool regions_are_adjacent(efi_memory_desc_t *left, + efi_memory_desc_t *right) +{ + u64 left_end; + + if (left == NULL || right == NULL) + return false; + + left_end = left->phys_addr + left->num_pages * EFI_PAGE_SIZE; + + return left_end == right->phys_addr; +} + +/* + * Returns whether region @left and region @right have compatible memory type + * mapping attributes, and are both EFI_MEMORY_RUNTIME regions. + */ +static bool regions_have_compatible_memory_type_attrs(efi_memory_desc_t *left, + efi_memory_desc_t *right) +{ + static const u64 mem_type_mask = EFI_MEMORY_WB | EFI_MEMORY_WT | + EFI_MEMORY_WC | EFI_MEMORY_UC | + EFI_MEMORY_RUNTIME; + + return ((left->attribute ^ right->attribute) & mem_type_mask) == 0; +} + /* * efi_get_virtmap() - create a virtual mapping for the EFI memory map * @@ -317,33 +356,52 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size, int *count) { u64 efi_virt_base = EFI_RT_VIRTUAL_BASE; - efi_memory_desc_t *out = runtime_map; + efi_memory_desc_t *in, *prev = NULL, *out = runtime_map; int l; - for (l = 0; l < map_size; l += desc_size) { - efi_memory_desc_t *in = (void *)memory_map + l; + /* + * To work around potential issues with the Properties Table feature + * introduced in UEFI 2.5, which may split PE/COFF executable images + * in memory into several RuntimeServicesCode and RuntimeServicesData + * regions, we need to preserve the relative offsets between adjacent + * EFI_MEMORY_RUNTIME regions with the same memory type attributes. + * The easiest way to find adjacent regions is to sort the memory map + * before traversing it. + */ + sort(memory_map, map_size / desc_size, desc_size, cmp_mem_desc, NULL); + + for (l = 0; l < map_size; l += desc_size, prev = in) { u64 paddr, size; + in = (void *)memory_map + l; if (!(in->attribute & EFI_MEMORY_RUNTIME)) continue; + paddr = in->phys_addr; + size = in->num_pages * EFI_PAGE_SIZE; + /* * Make the mapping compatible with 64k pages: this allows * a 4k page size kernel to kexec a 64k page size kernel and * vice versa. */ - paddr = round_down(in->phys_addr, SZ_64K); - size = round_up(in->num_pages * EFI_PAGE_SIZE + - in->phys_addr - paddr, SZ_64K); - - /* - * Avoid wasting memory on PTEs by choosing a virtual base that - * is compatible with section mappings if this region has the - * appropriate size and physical alignment. (Sections are 2 MB - * on 4k granule kernels) - */ - if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M) - efi_virt_base = round_up(efi_virt_base, SZ_2M); + if (!regions_are_adjacent(prev, in) || + !regions_have_compatible_memory_type_attrs(prev, in)) { + + paddr = round_down(in->phys_addr, SZ_64K); + size += in->phys_addr - paddr; + + /* + * Avoid wasting memory on PTEs by choosing a virtual + * base that is compatible with section mappings if this + * region has the appropriate size and physical + * alignment. (Sections are 2 MB on 4k granule kernels) + */ + if (IS_ALIGNED(in->phys_addr, SZ_2M) && size >= SZ_2M) + efi_virt_base = round_up(efi_virt_base, SZ_2M); + else + efi_virt_base = round_up(efi_virt_base, SZ_64K); + } in->virt_addr = efi_virt_base + in->phys_addr - paddr; efi_virt_base += size; -- cgit