diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/include/uapi/asm/elf.h | 16 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 89 | ||||
| -rw-r--r-- | fs/binfmt_elf.c | 4 | ||||
| -rw-r--r-- | include/uapi/linux/elf.h | 1 |
5 files changed, 109 insertions, 2 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6f1c31f4b9ab..d1fe732979d4 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -107,6 +107,7 @@ config X86 select ARCH_HAS_DEBUG_WX select ARCH_HAS_ZONE_DMA_SET if EXPERT select ARCH_HAVE_NMI_SAFE_CMPXCHG + select ARCH_HAVE_EXTRA_ELF_NOTES select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI select ARCH_MIGHT_HAVE_PC_PARPORT diff --git a/arch/x86/include/uapi/asm/elf.h b/arch/x86/include/uapi/asm/elf.h new file mode 100644 index 000000000000..468e135fa285 --- /dev/null +++ b/arch/x86/include/uapi/asm/elf.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_X86_ELF_H +#define _UAPI_ASM_X86_ELF_H + +#include <linux/types.h> + +struct x86_xfeat_component { + __u32 type; + __u32 size; + __u32 offset; + __u32 flags; +} __packed; + +_Static_assert(sizeof(struct x86_xfeat_component) % 4 == 0, "x86_xfeat_component is not aligned"); + +#endif /* _UAPI_ASM_X86_ELF_H */ diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 1339f8328db5..53d9f01d5988 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -13,6 +13,7 @@ #include <linux/seq_file.h> #include <linux/proc_fs.h> #include <linux/vmalloc.h> +#include <linux/coredump.h> #include <asm/fpu/api.h> #include <asm/fpu/regset.h> @@ -23,6 +24,8 @@ #include <asm/prctl.h> #include <asm/elf.h> +#include <uapi/asm/elf.h> + #include "context.h" #include "internal.h" #include "legacy.h" @@ -1841,3 +1844,89 @@ int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns, return 0; } #endif /* CONFIG_PROC_PID_ARCH_STATUS */ + +#ifdef CONFIG_COREDUMP +static const char owner_name[] = "LINUX"; + +/* + * Dump type, size, offset and flag values for every xfeature that is present. + */ +static int dump_xsave_layout_desc(struct coredump_params *cprm) +{ + int num_records = 0; + int i; + + for_each_extended_xfeature(i, fpu_user_cfg.max_features) { + struct x86_xfeat_component xc = { + .type = i, + .size = xstate_sizes[i], + .offset = xstate_offsets[i], + /* reserved for future use */ + .flags = 0, + }; + + if (!dump_emit(cprm, &xc, sizeof(xc))) + return 0; + + num_records++; + } + return num_records; +} + +static u32 get_xsave_desc_size(void) +{ + u32 cnt = 0; + u32 i; + + for_each_extended_xfeature(i, fpu_user_cfg.max_features) + cnt++; + + return cnt * (sizeof(struct x86_xfeat_component)); +} + +int elf_coredump_extra_notes_write(struct coredump_params *cprm) +{ + int num_records = 0; + struct elf_note en; + + if (!fpu_user_cfg.max_features) + return 0; + + en.n_namesz = sizeof(owner_name); + en.n_descsz = get_xsave_desc_size(); + en.n_type = NT_X86_XSAVE_LAYOUT; + + if (!dump_emit(cprm, &en, sizeof(en))) + return 1; + if (!dump_emit(cprm, owner_name, en.n_namesz)) + return 1; + if (!dump_align(cprm, 4)) + return 1; + + num_records = dump_xsave_layout_desc(cprm); + if (!num_records) + return 1; + + /* Total size should be equal to the number of records */ + if ((sizeof(struct x86_xfeat_component) * num_records) != en.n_descsz) + return 1; + + return 0; +} + +int elf_coredump_extra_notes_size(void) +{ + int size; + + if (!fpu_user_cfg.max_features) + return 0; + + /* .note header */ + size = sizeof(struct elf_note); + /* Name plus alignment to 4 bytes */ + size += roundup(sizeof(owner_name), 4); + size += get_xsave_desc_size(); + + return size; +} +#endif /* CONFIG_COREDUMP */ diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 19fa49cd9907..01bcbe7fdebd 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -2039,7 +2039,7 @@ static int elf_core_dump(struct coredump_params *cprm) { size_t sz = info.size; - /* For cell spufs */ + /* For cell spufs and x86 xstate */ sz += elf_coredump_extra_notes_size(); phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); @@ -2103,7 +2103,7 @@ static int elf_core_dump(struct coredump_params *cprm) if (!write_note_info(&info, cprm)) goto end_coredump; - /* For cell spufs */ + /* For cell spufs and x86 xstate */ if (elf_coredump_extra_notes_write(cprm)) goto end_coredump; diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index 81762ff3c99e..b9935988da5c 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -411,6 +411,7 @@ typedef struct elf64_shdr { #define NT_X86_XSTATE 0x202 /* x86 extended state using xsave */ /* Old binutils treats 0x203 as a CET state */ #define NT_X86_SHSTK 0x204 /* x86 SHSTK state */ +#define NT_X86_XSAVE_LAYOUT 0x205 /* XSAVE layout description */ #define NT_S390_HIGH_GPRS 0x300 /* s390 upper register halves */ #define NT_S390_TIMER 0x301 /* s390 timer register */ #define NT_S390_TODCMP 0x302 /* s390 TOD clock comparator register */ |