From 88c26d7d2bd8175f97ad14cf2c79f199e7307efc Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 9 Aug 2022 16:45:17 +0200 Subject: [PATCH] efi/libstub: use EFI provided memcpy/memset routines LoongArch inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5OHOB -------------------------------- The stub is used in different execution environments, but on arm64, RISC-V and LoongArch, we still use the core kernel's implementation of memcpy and memset, as they are just a branch instruction away, and can generally be reused even from code such as the EFI stub that runs in a completely different address space. KAsan complicates this slightly, resulting in the need for some hacks to expose the uninstrumented, __ prefixed versions as the normal ones, as the latter are instrumented to include the KAsan checks, which only work in the core kernel. Unfortunately, #define'ing memcpy to __memcpy when building C code does not guarantee that no explicit memcpy() calls will be emitted. And with the upcoming zboot support, which consists of a separate binary which therefore needs its own implementation of memcpy/memset anyway, it's better to provide one explicitly instead of linking to the existing one. Given that EFI exposes implementations of memmove() and memset() via the boot services table, let's wire those up in the appropriate way, and drop the references to the core kernel ones. Signed-off-by: Ard Biesheuvel Signed-off-by: Huacai Chen --- arch/arm64/kernel/image-vars.h | 9 ------- arch/loongarch/kernel/image-vars.h | 3 --- arch/riscv/kernel/image-vars.h | 9 ------- drivers/firmware/efi/libstub/Makefile | 2 +- drivers/firmware/efi/libstub/efistub.h | 4 +-- drivers/firmware/efi/libstub/intrinsics.c | 30 +++++++++++++++++++++++ 6 files changed, 33 insertions(+), 24 deletions(-) create mode 100644 drivers/firmware/efi/libstub/intrinsics.c diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index 7ea4b84f1518..8d3fede89ae1 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -27,9 +27,6 @@ __efistub_primary_entry_offset = primary_entry - _text; */ __efistub_memcmp = __pi_memcmp; __efistub_memchr = __pi_memchr; -__efistub_memcpy = __pi_memcpy; -__efistub_memmove = __pi_memmove; -__efistub_memset = __pi_memset; __efistub_strlen = __pi_strlen; __efistub_strnlen = __pi_strnlen; __efistub_strcmp = __pi_strcmp; @@ -38,12 +35,6 @@ __efistub_strrchr = __pi_strrchr; __efistub_strchr = __pi_strchr; __efistub___clean_dcache_area_poc = __pi___clean_dcache_area_poc; -#ifdef CONFIG_KASAN -__efistub___memcpy = __pi_memcpy; -__efistub___memmove = __pi_memmove; -__efistub___memset = __pi_memset; -#endif - __efistub__text = _text; __efistub__end = _end; __efistub__edata = _edata; diff --git a/arch/loongarch/kernel/image-vars.h b/arch/loongarch/kernel/image-vars.h index c901ebb903f2..88f5d81702df 100644 --- a/arch/loongarch/kernel/image-vars.h +++ b/arch/loongarch/kernel/image-vars.h @@ -9,9 +9,6 @@ __efistub_memcmp = memcmp; __efistub_memchr = memchr; -__efistub_memcpy = memcpy; -__efistub_memmove = memmove; -__efistub_memset = memset; __efistub_strcat = strcat; __efistub_strcmp = strcmp; __efistub_strlen = strlen; diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h index 8c212efb37a6..bf1c73b5a5b9 100644 --- a/arch/riscv/kernel/image-vars.h +++ b/arch/riscv/kernel/image-vars.h @@ -25,21 +25,12 @@ */ __efistub_memcmp = memcmp; __efistub_memchr = memchr; -__efistub_memcpy = memcpy; -__efistub_memmove = memmove; -__efistub_memset = memset; __efistub_strlen = strlen; __efistub_strnlen = strnlen; __efistub_strcmp = strcmp; __efistub_strncmp = strncmp; __efistub_strrchr = strrchr; -#ifdef CONFIG_KASAN -__efistub___memcpy = memcpy; -__efistub___memmove = memmove; -__efistub___memset = memset; -#endif - __efistub__start = _start; __efistub__start_kernel = _start_kernel; __efistub__end = _end; diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 97c7c5deeb8a..5b5ae50d805a 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -63,7 +63,7 @@ efi-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE $(call if_changed_rule,cc_o_c) -lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o \ +lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o fdt.o string.o intrinsics.o \ $(patsubst %.c,lib-%.o,$(efi-deps-y)) lib-$(CONFIG_ARM) += arm32-stub.o diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index 969d964d08af..db009721f543 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -298,8 +298,8 @@ union efi_boot_services { efi_status_t (__efiapi *install_multiple_protocol_interfaces)(efi_handle_t *, ...); efi_status_t (__efiapi *uninstall_multiple_protocol_interfaces)(efi_handle_t, ...); void *calculate_crc32; - void *copy_mem; - void *set_mem; + void (__efiapi *copy_mem)(void *, const void *, unsigned long); + void (__efiapi *set_mem)(void *, unsigned long, unsigned char); void *create_event_ex; }; struct { diff --git a/drivers/firmware/efi/libstub/intrinsics.c b/drivers/firmware/efi/libstub/intrinsics.c new file mode 100644 index 000000000000..a04ab39292b6 --- /dev/null +++ b/drivers/firmware/efi/libstub/intrinsics.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include + +#include "efistub.h" + +#ifdef CONFIG_KASAN +#undef memcpy +#undef memmove +#undef memset +void *__memcpy(void *__dest, const void *__src, size_t __n) __alias(memcpy); +void *__memmove(void *__dest, const void *__src, size_t count) __alias(memmove); +void *__memset(void *s, int c, size_t count) __alias(memset); +#endif + +void *memcpy(void *dst, const void *src, size_t len) +{ + efi_bs_call(copy_mem, dst, src, len); + return dst; +} + +extern void *memmove(void *dst, const void *src, size_t len) __alias(memcpy); + +void *memset(void *dst, int c, size_t len) +{ + efi_bs_call(set_mem, dst, len, c & U8_MAX); + return dst; +} -- GitLab