From: Sven Schnelle <svens@xxxxxxxxxxxxxx> Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxxx> --- patch generated with 'git format-patch -C' in order to see the modifications done in kexec_elf.c in addition to copying it from arch/powerpc/kernel/kexec_elf_64.c arch/Kconfig | 3 + arch/powerpc/Kconfig | 1 + arch/powerpc/kernel/kexec_elf_64.c | 547 +-------------------- include/linux/kexec.h | 35 ++ kernel/Makefile | 1 + .../kernel/kexec_elf_64.c => kernel/kexec_elf.c | 264 +++------- 6 files changed, 118 insertions(+), 733 deletions(-) copy arch/powerpc/kernel/kexec_elf_64.c => kernel/kexec_elf.c (64%) diff --git a/arch/Kconfig b/arch/Kconfig index 33687dddd86a..c7c75fbc0b79 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -18,6 +18,9 @@ config KEXEC_CORE select CRASH_CORE bool +config KEXEC_ELF + bool + config HAVE_IMA_KEXEC bool diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 2d0be82c3061..447b6e3ad999 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -501,6 +501,7 @@ config KEXEC_FILE select KEXEC_CORE select HAVE_IMA_KEXEC select BUILD_BIN2C + select KEXEC_ELF depends on PPC64 depends on CRYPTO=y depends on CRYPTO_SHA256=y diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c index ba4f18a43ee8..d062c5991722 100644 --- a/arch/powerpc/kernel/kexec_elf_64.c +++ b/arch/powerpc/kernel/kexec_elf_64.c @@ -31,539 +31,7 @@ #include <linux/slab.h> #include <linux/types.h> -#define PURGATORY_STACK_SIZE (16 * 1024) - -#define elf_addr_to_cpu elf64_to_cpu - -#ifndef Elf_Rel -#define Elf_Rel Elf64_Rel -#endif /* Elf_Rel */ - -struct elf_info { - /* - * Where the ELF binary contents are kept. - * Memory managed by the user of the struct. - */ - const char *buffer; - - const struct elfhdr *ehdr; - const struct elf_phdr *proghdrs; - struct elf_shdr *sechdrs; -}; - -static inline bool elf_is_elf_file(const struct elfhdr *ehdr) -{ - return memcmp(ehdr->e_ident, ELFMAG, SELFMAG) == 0; -} - -static uint64_t elf64_to_cpu(const struct elfhdr *ehdr, uint64_t value) -{ - if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - value = le64_to_cpu(value); - else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - value = be64_to_cpu(value); - - return value; -} - -static uint16_t elf16_to_cpu(const struct elfhdr *ehdr, uint16_t value) -{ - if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - value = le16_to_cpu(value); - else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - value = be16_to_cpu(value); - - return value; -} - -static uint32_t elf32_to_cpu(const struct elfhdr *ehdr, uint32_t value) -{ - if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - value = le32_to_cpu(value); - else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - value = be32_to_cpu(value); - - return value; -} - -/** - * elf_is_ehdr_sane - check that it is safe to use the ELF header - * @buf_len: size of the buffer in which the ELF file is loaded. - */ -static bool elf_is_ehdr_sane(const struct elfhdr *ehdr, size_t buf_len) -{ - if (ehdr->e_phnum > 0 && ehdr->e_phentsize != sizeof(struct elf_phdr)) { - pr_debug("Bad program header size.\n"); - return false; - } else if (ehdr->e_shnum > 0 && - ehdr->e_shentsize != sizeof(struct elf_shdr)) { - pr_debug("Bad section header size.\n"); - return false; - } else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT || - ehdr->e_version != EV_CURRENT) { - pr_debug("Unknown ELF version.\n"); - return false; - } - - if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) { - size_t phdr_size; - - /* - * e_phnum is at most 65535 so calculating the size of the - * program header cannot overflow. - */ - phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum; - - /* Sanity check the program header table location. */ - if (ehdr->e_phoff + phdr_size < ehdr->e_phoff) { - pr_debug("Program headers at invalid location.\n"); - return false; - } else if (ehdr->e_phoff + phdr_size > buf_len) { - pr_debug("Program headers truncated.\n"); - return false; - } - } - - if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) { - size_t shdr_size; - - /* - * e_shnum is at most 65536 so calculating - * the size of the section header cannot overflow. - */ - shdr_size = sizeof(struct elf_shdr) * ehdr->e_shnum; - - /* Sanity check the section header table location. */ - if (ehdr->e_shoff + shdr_size < ehdr->e_shoff) { - pr_debug("Section headers at invalid location.\n"); - return false; - } else if (ehdr->e_shoff + shdr_size > buf_len) { - pr_debug("Section headers truncated.\n"); - return false; - } - } - - return true; -} - -static int elf_read_ehdr(const char *buf, size_t len, struct elfhdr *ehdr) -{ - struct elfhdr *buf_ehdr; - - if (len < sizeof(*buf_ehdr)) { - pr_debug("Buffer is too small to hold ELF header.\n"); - return -ENOEXEC; - } - - memset(ehdr, 0, sizeof(*ehdr)); - memcpy(ehdr->e_ident, buf, sizeof(ehdr->e_ident)); - if (!elf_is_elf_file(ehdr)) { - pr_debug("No ELF header magic.\n"); - return -ENOEXEC; - } - - if (ehdr->e_ident[EI_CLASS] != ELF_CLASS) { - pr_debug("Not a supported ELF class.\n"); - return -ENOEXEC; - } else if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB && - ehdr->e_ident[EI_DATA] != ELFDATA2MSB) { - pr_debug("Not a supported ELF data format.\n"); - return -ENOEXEC; - } - - buf_ehdr = (struct elfhdr *) buf; - if (elf16_to_cpu(ehdr, buf_ehdr->e_ehsize) != sizeof(*buf_ehdr)) { - pr_debug("Bad ELF header size.\n"); - return -ENOEXEC; - } - - ehdr->e_type = elf16_to_cpu(ehdr, buf_ehdr->e_type); - ehdr->e_machine = elf16_to_cpu(ehdr, buf_ehdr->e_machine); - ehdr->e_version = elf32_to_cpu(ehdr, buf_ehdr->e_version); - ehdr->e_entry = elf_addr_to_cpu(ehdr, buf_ehdr->e_entry); - ehdr->e_phoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_phoff); - ehdr->e_shoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_shoff); - ehdr->e_flags = elf32_to_cpu(ehdr, buf_ehdr->e_flags); - ehdr->e_phentsize = elf16_to_cpu(ehdr, buf_ehdr->e_phentsize); - ehdr->e_phnum = elf16_to_cpu(ehdr, buf_ehdr->e_phnum); - ehdr->e_shentsize = elf16_to_cpu(ehdr, buf_ehdr->e_shentsize); - ehdr->e_shnum = elf16_to_cpu(ehdr, buf_ehdr->e_shnum); - ehdr->e_shstrndx = elf16_to_cpu(ehdr, buf_ehdr->e_shstrndx); - - return elf_is_ehdr_sane(ehdr, len) ? 0 : -ENOEXEC; -} - -/** - * elf_is_phdr_sane - check that it is safe to use the program header - * @buf_len: size of the buffer in which the ELF file is loaded. - */ -static bool elf_is_phdr_sane(const struct elf_phdr *phdr, size_t buf_len) -{ - - if (phdr->p_offset + phdr->p_filesz < phdr->p_offset) { - pr_debug("ELF segment location wraps around.\n"); - return false; - } else if (phdr->p_offset + phdr->p_filesz > buf_len) { - pr_debug("ELF segment not in file.\n"); - return false; - } else if (phdr->p_paddr + phdr->p_memsz < phdr->p_paddr) { - pr_debug("ELF segment address wraps around.\n"); - return false; - } - - return true; -} - -static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info, - int idx) -{ - /* Override the const in proghdrs, we are the ones doing the loading. */ - struct elf_phdr *phdr = (struct elf_phdr *) &elf_info->proghdrs[idx]; - const char *pbuf; - struct elf_phdr *buf_phdr; - - pbuf = buf + elf_info->ehdr->e_phoff + (idx * sizeof(*buf_phdr)); - buf_phdr = (struct elf_phdr *) pbuf; - - phdr->p_type = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_type); - phdr->p_offset = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_offset); - phdr->p_paddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_paddr); - phdr->p_vaddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr); - phdr->p_flags = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_flags); - - /* - * The following fields have a type equivalent to Elf_Addr - * both in 32 bit and 64 bit ELF. - */ - phdr->p_filesz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_filesz); - phdr->p_memsz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_memsz); - phdr->p_align = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_align); - - return elf_is_phdr_sane(phdr, len) ? 0 : -ENOEXEC; -} - -/** - * elf_read_phdrs - read the program headers from the buffer - * - * This function assumes that the program header table was checked for sanity. - * Use elf_is_ehdr_sane() if it wasn't. - */ -static int elf_read_phdrs(const char *buf, size_t len, - struct elf_info *elf_info) -{ - size_t phdr_size, i; - const struct elfhdr *ehdr = elf_info->ehdr; - - /* - * e_phnum is at most 65535 so calculating the size of the - * program header cannot overflow. - */ - phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum; - - elf_info->proghdrs = kzalloc(phdr_size, GFP_KERNEL); - if (!elf_info->proghdrs) - return -ENOMEM; - - for (i = 0; i < ehdr->e_phnum; i++) { - int ret; - - ret = elf_read_phdr(buf, len, elf_info, i); - if (ret) { - kfree(elf_info->proghdrs); - elf_info->proghdrs = NULL; - return ret; - } - } - - return 0; -} - -/** - * elf_is_shdr_sane - check that it is safe to use the section header - * @buf_len: size of the buffer in which the ELF file is loaded. - */ -static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len) -{ - bool size_ok; - - /* SHT_NULL headers have undefined values, so we can't check them. */ - if (shdr->sh_type == SHT_NULL) - return true; - - /* Now verify sh_entsize */ - switch (shdr->sh_type) { - case SHT_SYMTAB: - size_ok = shdr->sh_entsize == sizeof(Elf_Sym); - break; - case SHT_RELA: - size_ok = shdr->sh_entsize == sizeof(Elf_Rela); - break; - case SHT_DYNAMIC: - size_ok = shdr->sh_entsize == sizeof(Elf_Dyn); - break; - case SHT_REL: - size_ok = shdr->sh_entsize == sizeof(Elf_Rel); - break; - case SHT_NOTE: - case SHT_PROGBITS: - case SHT_HASH: - case SHT_NOBITS: - default: - /* - * This is a section whose entsize requirements - * I don't care about. If I don't know about - * the section I can't care about it's entsize - * requirements. - */ - size_ok = true; - break; - } - - if (!size_ok) { - pr_debug("ELF section with wrong entry size.\n"); - return false; - } else if (shdr->sh_addr + shdr->sh_size < shdr->sh_addr) { - pr_debug("ELF section address wraps around.\n"); - return false; - } - - if (shdr->sh_type != SHT_NOBITS) { - if (shdr->sh_offset + shdr->sh_size < shdr->sh_offset) { - pr_debug("ELF section location wraps around.\n"); - return false; - } else if (shdr->sh_offset + shdr->sh_size > buf_len) { - pr_debug("ELF section not in file.\n"); - return false; - } - } - - return true; -} - -static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info, - int idx) -{ - struct elf_shdr *shdr = &elf_info->sechdrs[idx]; - const struct elfhdr *ehdr = elf_info->ehdr; - const char *sbuf; - struct elf_shdr *buf_shdr; - - sbuf = buf + ehdr->e_shoff + idx * sizeof(*buf_shdr); - buf_shdr = (struct elf_shdr *) sbuf; - - shdr->sh_name = elf32_to_cpu(ehdr, buf_shdr->sh_name); - shdr->sh_type = elf32_to_cpu(ehdr, buf_shdr->sh_type); - shdr->sh_addr = elf_addr_to_cpu(ehdr, buf_shdr->sh_addr); - shdr->sh_offset = elf_addr_to_cpu(ehdr, buf_shdr->sh_offset); - shdr->sh_link = elf32_to_cpu(ehdr, buf_shdr->sh_link); - shdr->sh_info = elf32_to_cpu(ehdr, buf_shdr->sh_info); - - /* - * The following fields have a type equivalent to Elf_Addr - * both in 32 bit and 64 bit ELF. - */ - shdr->sh_flags = elf_addr_to_cpu(ehdr, buf_shdr->sh_flags); - shdr->sh_size = elf_addr_to_cpu(ehdr, buf_shdr->sh_size); - shdr->sh_addralign = elf_addr_to_cpu(ehdr, buf_shdr->sh_addralign); - shdr->sh_entsize = elf_addr_to_cpu(ehdr, buf_shdr->sh_entsize); - - return elf_is_shdr_sane(shdr, len) ? 0 : -ENOEXEC; -} - -/** - * elf_read_shdrs - read the section headers from the buffer - * - * This function assumes that the section header table was checked for sanity. - * Use elf_is_ehdr_sane() if it wasn't. - */ -static int elf_read_shdrs(const char *buf, size_t len, - struct elf_info *elf_info) -{ - size_t shdr_size, i; - - /* - * e_shnum is at most 65536 so calculating - * the size of the section header cannot overflow. - */ - shdr_size = sizeof(struct elf_shdr) * elf_info->ehdr->e_shnum; - - elf_info->sechdrs = kzalloc(shdr_size, GFP_KERNEL); - if (!elf_info->sechdrs) - return -ENOMEM; - - for (i = 0; i < elf_info->ehdr->e_shnum; i++) { - int ret; - - ret = elf_read_shdr(buf, len, elf_info, i); - if (ret) { - kfree(elf_info->sechdrs); - elf_info->sechdrs = NULL; - return ret; - } - } - - return 0; -} - -/** - * elf_read_from_buffer - read ELF file and sets up ELF header and ELF info - * @buf: Buffer to read ELF file from. - * @len: Size of @buf. - * @ehdr: Pointer to existing struct which will be populated. - * @elf_info: Pointer to existing struct which will be populated. - * - * This function allows reading ELF files with different byte order than - * the kernel, byte-swapping the fields as needed. - * - * Return: - * On success returns 0, and the caller should call elf_free_info(elf_info) to - * free the memory allocated for the section and program headers. - */ -int elf_read_from_buffer(const char *buf, size_t len, struct elfhdr *ehdr, - struct elf_info *elf_info) -{ - int ret; - - ret = elf_read_ehdr(buf, len, ehdr); - if (ret) - return ret; - - elf_info->buffer = buf; - elf_info->ehdr = ehdr; - if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) { - ret = elf_read_phdrs(buf, len, elf_info); - if (ret) - return ret; - } - if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) { - ret = elf_read_shdrs(buf, len, elf_info); - if (ret) { - kfree(elf_info->proghdrs); - return ret; - } - } - - return 0; -} - -/** - * elf_free_info - free memory allocated by elf_read_from_buffer - */ -void elf_free_info(struct elf_info *elf_info) -{ - kfree(elf_info->proghdrs); - kfree(elf_info->sechdrs); - memset(elf_info, 0, sizeof(*elf_info)); -} -/** - * build_elf_exec_info - read ELF executable and check that we can use it - */ -static int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr, - struct elf_info *elf_info) -{ - int i; - int ret; - - ret = elf_read_from_buffer(buf, len, ehdr, elf_info); - if (ret) - return ret; - - /* Big endian vmlinux has type ET_DYN. */ - if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) { - pr_err("Not an ELF executable.\n"); - goto error; - } else if (!elf_info->proghdrs) { - pr_err("No ELF program header.\n"); - goto error; - } - - for (i = 0; i < ehdr->e_phnum; i++) { - /* - * Kexec does not support loading interpreters. - * In addition this check keeps us from attempting - * to kexec ordinay executables. - */ - if (elf_info->proghdrs[i].p_type == PT_INTERP) { - pr_err("Requires an ELF interpreter.\n"); - goto error; - } - } - - return 0; -error: - elf_free_info(elf_info); - return -ENOEXEC; -} - -static int elf64_probe(const char *buf, unsigned long len) -{ - struct elfhdr ehdr; - struct elf_info elf_info; - int ret; - - ret = build_elf_exec_info(buf, len, &ehdr, &elf_info); - if (ret) - return ret; - - elf_free_info(&elf_info); - - return elf_check_arch(&ehdr) ? 0 : -ENOEXEC; -} - -/** - * elf_exec_load - load ELF executable image - * @lowest_load_addr: On return, will be the address where the first PT_LOAD - * section will be loaded in memory. - * - * Return: - * 0 on success, negative value on failure. - */ -static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr, - struct elf_info *elf_info, - unsigned long *lowest_load_addr) -{ - unsigned long base = 0, lowest_addr = UINT_MAX; - int ret; - size_t i; - struct kexec_buf kbuf = { .image = image, .buf_max = ppc64_rma_size, - .top_down = false }; - - /* Read in the PT_LOAD segments. */ - for (i = 0; i < ehdr->e_phnum; i++) { - unsigned long load_addr; - size_t size; - const struct elf_phdr *phdr; - - phdr = &elf_info->proghdrs[i]; - if (phdr->p_type != PT_LOAD) - continue; - - size = phdr->p_filesz; - if (size > phdr->p_memsz) - size = phdr->p_memsz; - - kbuf.buffer = (void *) elf_info->buffer + phdr->p_offset; - kbuf.bufsz = size; - kbuf.memsz = phdr->p_memsz; - kbuf.buf_align = phdr->p_align; - kbuf.buf_min = phdr->p_paddr + base; - ret = kexec_add_buffer(&kbuf); - if (ret) - goto out; - load_addr = kbuf.mem; - - if (load_addr < lowest_addr) - lowest_addr = load_addr; - } - - /* Update entry point to reflect new load address. */ - ehdr->e_entry += base; - - *lowest_load_addr = lowest_addr; - ret = 0; - out: - return ret; -} +#define PURGATORY_STACK_SIZE (16 * 1024) static void *elf64_load(struct kimage *image, char *kernel_buf, unsigned long kernel_len, char *initrd, @@ -577,17 +45,17 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, void *fdt; const void *slave_code; struct elfhdr ehdr; - struct elf_info elf_info; + struct kexec_elf_info elf_info; struct kexec_buf kbuf = { .image = image, .buf_min = 0, .buf_max = ppc64_rma_size }; struct kexec_buf pbuf = { .image = image, .buf_min = 0, .buf_max = ppc64_rma_size, .top_down = true }; - ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info); + ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info); if (ret) goto out; - ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr); + ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr); if (ret) goto out; @@ -606,6 +74,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, kbuf.bufsz = kbuf.memsz = initrd_len; kbuf.buf_align = PAGE_SIZE; kbuf.top_down = false; + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; ret = kexec_add_buffer(&kbuf); if (ret) goto out; @@ -638,6 +107,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, kbuf.bufsz = kbuf.memsz = fdt_size; kbuf.buf_align = PAGE_SIZE; kbuf.top_down = true; + kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; ret = kexec_add_buffer(&kbuf); if (ret) goto out; @@ -652,13 +122,12 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, pr_err("Error setting up the purgatory.\n"); out: - elf_free_info(&elf_info); - + kexec_free_elf_info(&elf_info); /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */ return ret ? ERR_PTR(ret) : fdt; } const struct kexec_file_ops kexec_elf64_ops = { - .probe = elf64_probe, + .probe = kexec_elf_probe, .load = elf64_load, }; diff --git a/include/linux/kexec.h b/include/linux/kexec.h index b9b1bc5f9669..72648b18b778 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -216,6 +216,41 @@ extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, void **addr, unsigned long *sz); #endif /* CONFIG_KEXEC_FILE */ +#ifdef CONFIG_KEXEC_ELF + +struct kexec_elf_info { + /* + * Where the ELF binary contents are kept. + * Memory managed by the user of the struct. + */ + const char *buffer; + + const struct elfhdr *ehdr; + const struct elf_phdr *proghdrs; + struct elf_shdr *sechdrs; +}; + +void kexec_free_elf_info(struct kexec_elf_info *elf_info); + +int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, + struct kexec_elf_info *elf_info); + +int kexec_elf_kernel_load(struct kimage *image, struct kexec_buf *kbuf, + char *kernel_buf, unsigned long kernel_len, + unsigned long *kernel_load_addr); + +int kexec_elf_probe(const char *buf, unsigned long len); + +int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, + struct kexec_elf_info *elf_info, + struct kexec_buf *kbuf, + unsigned long *lowest_load_addr); + +int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, + struct kexec_elf_info *elf_info, + struct kexec_buf *kbuf, + unsigned long *lowest_load_addr); +#endif struct kimage { kimage_entry_t head; kimage_entry_t *entry; diff --git a/kernel/Makefile b/kernel/Makefile index 6c57e78817da..081b378050d0 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -63,6 +63,7 @@ obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_KEXEC_CORE) += kexec_core.o obj-$(CONFIG_KEXEC) += kexec.o obj-$(CONFIG_KEXEC_FILE) += kexec_file.o +obj-$(CONFIG_KEXEC_ELF) += kexec_elf.o obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o obj-$(CONFIG_COMPAT) += compat.o obj-$(CONFIG_CGROUPS) += cgroup/ diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/kernel/kexec_elf.c similarity index 64% copy from arch/powerpc/kernel/kexec_elf_64.c copy to kernel/kexec_elf.c index ba4f18a43ee8..07e5bcc79bba 100644 --- a/arch/powerpc/kernel/kexec_elf_64.c +++ b/kernel/kexec_elf.c @@ -1,55 +1,13 @@ -/* - * Load ELF vmlinux file for the kexec_file_load syscall. - * - * Copyright (C) 2004 Adam Litke (agl@xxxxxxxxxx) - * Copyright (C) 2004 IBM Corp. - * Copyright (C) 2005 R Sharada (sharada@xxxxxxxxxx) - * Copyright (C) 2006 Mohan Kumar M (mohan@xxxxxxxxxx) - * Copyright (C) 2016 IBM Corporation - * - * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c. - * Heavily modified for the kernel by - * Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxxxxxxx>. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation (version 2 of the License). - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ +// SPDX-License-Identifier: GPL-2.0 #define pr_fmt(fmt) "kexec_elf: " fmt #include <linux/elf.h> #include <linux/kexec.h> -#include <linux/libfdt.h> #include <linux/module.h> -#include <linux/of_fdt.h> #include <linux/slab.h> #include <linux/types.h> -#define PURGATORY_STACK_SIZE (16 * 1024) - -#define elf_addr_to_cpu elf64_to_cpu - -#ifndef Elf_Rel -#define Elf_Rel Elf64_Rel -#endif /* Elf_Rel */ - -struct elf_info { - /* - * Where the ELF binary contents are kept. - * Memory managed by the user of the struct. - */ - const char *buffer; - - const struct elfhdr *ehdr; - const struct elf_phdr *proghdrs; - struct elf_shdr *sechdrs; -}; static inline bool elf_is_elf_file(const struct elfhdr *ehdr) { @@ -66,22 +24,22 @@ static uint64_t elf64_to_cpu(const struct elfhdr *ehdr, uint64_t value) return value; } -static uint16_t elf16_to_cpu(const struct elfhdr *ehdr, uint16_t value) +static uint32_t elf32_to_cpu(const struct elfhdr *ehdr, uint32_t value) { if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - value = le16_to_cpu(value); + value = le32_to_cpu(value); else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - value = be16_to_cpu(value); + value = be32_to_cpu(value); return value; } -static uint32_t elf32_to_cpu(const struct elfhdr *ehdr, uint32_t value) +static uint16_t elf16_to_cpu(const struct elfhdr *ehdr, uint16_t value) { if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) - value = le32_to_cpu(value); + value = le16_to_cpu(value); else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - value = be32_to_cpu(value); + value = be16_to_cpu(value); return value; } @@ -180,9 +138,9 @@ static int elf_read_ehdr(const char *buf, size_t len, struct elfhdr *ehdr) ehdr->e_type = elf16_to_cpu(ehdr, buf_ehdr->e_type); ehdr->e_machine = elf16_to_cpu(ehdr, buf_ehdr->e_machine); ehdr->e_version = elf32_to_cpu(ehdr, buf_ehdr->e_version); - ehdr->e_entry = elf_addr_to_cpu(ehdr, buf_ehdr->e_entry); - ehdr->e_phoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_phoff); - ehdr->e_shoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_shoff); + ehdr->e_entry = elf64_to_cpu(ehdr, buf_ehdr->e_entry); + ehdr->e_phoff = elf64_to_cpu(ehdr, buf_ehdr->e_phoff); + ehdr->e_shoff = elf64_to_cpu(ehdr, buf_ehdr->e_shoff); ehdr->e_flags = elf32_to_cpu(ehdr, buf_ehdr->e_flags); ehdr->e_phentsize = elf16_to_cpu(ehdr, buf_ehdr->e_phentsize); ehdr->e_phnum = elf16_to_cpu(ehdr, buf_ehdr->e_phnum); @@ -214,7 +172,7 @@ static bool elf_is_phdr_sane(const struct elf_phdr *phdr, size_t buf_len) return true; } -static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info, +static int elf_read_phdr(const char *buf, size_t len, struct kexec_elf_info *elf_info, int idx) { /* Override the const in proghdrs, we are the ones doing the loading. */ @@ -226,18 +184,18 @@ static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info, buf_phdr = (struct elf_phdr *) pbuf; phdr->p_type = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_type); - phdr->p_offset = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_offset); - phdr->p_paddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_paddr); - phdr->p_vaddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr); + phdr->p_offset = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_offset); + phdr->p_paddr = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_paddr); + phdr->p_vaddr = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr); phdr->p_flags = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_flags); /* * The following fields have a type equivalent to Elf_Addr * both in 32 bit and 64 bit ELF. */ - phdr->p_filesz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_filesz); - phdr->p_memsz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_memsz); - phdr->p_align = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_align); + phdr->p_filesz = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_filesz); + phdr->p_memsz = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_memsz); + phdr->p_align = elf64_to_cpu(elf_info->ehdr, buf_phdr->p_align); return elf_is_phdr_sane(phdr, len) ? 0 : -ENOEXEC; } @@ -249,7 +207,7 @@ static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info, * Use elf_is_ehdr_sane() if it wasn't. */ static int elf_read_phdrs(const char *buf, size_t len, - struct elf_info *elf_info) + struct kexec_elf_info *elf_info) { size_t phdr_size, i; const struct elfhdr *ehdr = elf_info->ehdr; @@ -296,13 +254,13 @@ static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len) size_ok = shdr->sh_entsize == sizeof(Elf_Sym); break; case SHT_RELA: - size_ok = shdr->sh_entsize == sizeof(Elf_Rela); + size_ok = shdr->sh_entsize == sizeof(Elf64_Rela); break; case SHT_DYNAMIC: size_ok = shdr->sh_entsize == sizeof(Elf_Dyn); break; case SHT_REL: - size_ok = shdr->sh_entsize == sizeof(Elf_Rel); + size_ok = shdr->sh_entsize == sizeof(Elf64_Rel); break; case SHT_NOTE: case SHT_PROGBITS: @@ -340,7 +298,7 @@ static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len) return true; } -static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info, +static int elf_read_shdr(const char *buf, size_t len, struct kexec_elf_info *elf_info, int idx) { struct elf_shdr *shdr = &elf_info->sechdrs[idx]; @@ -353,8 +311,8 @@ static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info, shdr->sh_name = elf32_to_cpu(ehdr, buf_shdr->sh_name); shdr->sh_type = elf32_to_cpu(ehdr, buf_shdr->sh_type); - shdr->sh_addr = elf_addr_to_cpu(ehdr, buf_shdr->sh_addr); - shdr->sh_offset = elf_addr_to_cpu(ehdr, buf_shdr->sh_offset); + shdr->sh_addr = elf64_to_cpu(ehdr, buf_shdr->sh_addr); + shdr->sh_offset = elf64_to_cpu(ehdr, buf_shdr->sh_offset); shdr->sh_link = elf32_to_cpu(ehdr, buf_shdr->sh_link); shdr->sh_info = elf32_to_cpu(ehdr, buf_shdr->sh_info); @@ -362,10 +320,10 @@ static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info, * The following fields have a type equivalent to Elf_Addr * both in 32 bit and 64 bit ELF. */ - shdr->sh_flags = elf_addr_to_cpu(ehdr, buf_shdr->sh_flags); - shdr->sh_size = elf_addr_to_cpu(ehdr, buf_shdr->sh_size); - shdr->sh_addralign = elf_addr_to_cpu(ehdr, buf_shdr->sh_addralign); - shdr->sh_entsize = elf_addr_to_cpu(ehdr, buf_shdr->sh_entsize); + shdr->sh_flags = elf64_to_cpu(ehdr, buf_shdr->sh_flags); + shdr->sh_size = elf64_to_cpu(ehdr, buf_shdr->sh_size); + shdr->sh_addralign = elf64_to_cpu(ehdr, buf_shdr->sh_addralign); + shdr->sh_entsize = elf64_to_cpu(ehdr, buf_shdr->sh_entsize); return elf_is_shdr_sane(shdr, len) ? 0 : -ENOEXEC; } @@ -377,7 +335,7 @@ static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info, * Use elf_is_ehdr_sane() if it wasn't. */ static int elf_read_shdrs(const char *buf, size_t len, - struct elf_info *elf_info) + struct kexec_elf_info *elf_info) { size_t shdr_size, i; @@ -416,11 +374,11 @@ static int elf_read_shdrs(const char *buf, size_t len, * the kernel, byte-swapping the fields as needed. * * Return: - * On success returns 0, and the caller should call elf_free_info(elf_info) to + * On success returns 0, and the caller should call kexec_free_elf_info(elf_info) to * free the memory allocated for the section and program headers. */ int elf_read_from_buffer(const char *buf, size_t len, struct elfhdr *ehdr, - struct elf_info *elf_info) + struct kexec_elf_info *elf_info) { int ret; @@ -447,19 +405,19 @@ int elf_read_from_buffer(const char *buf, size_t len, struct elfhdr *ehdr, } /** - * elf_free_info - free memory allocated by elf_read_from_buffer + * kexec_free_elf_info - free memory allocated by elf_read_from_buffer */ -void elf_free_info(struct elf_info *elf_info) +void kexec_free_elf_info(struct kexec_elf_info *elf_info) { kfree(elf_info->proghdrs); - kfree(elf_info->sechdrs); memset(elf_info, 0, sizeof(*elf_info)); } + /** - * build_elf_exec_info - read ELF executable and check that we can use it + * kexec_build_elf_info - read ELF executable and check that we can use it */ -static int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr, - struct elf_info *elf_info) +int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, + struct kexec_elf_info *elf_info) { int i; int ret; @@ -491,25 +449,10 @@ static int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr, return 0; error: - elf_free_info(elf_info); + kexec_free_elf_info(elf_info); return -ENOEXEC; } -static int elf64_probe(const char *buf, unsigned long len) -{ - struct elfhdr ehdr; - struct elf_info elf_info; - int ret; - - ret = build_elf_exec_info(buf, len, &ehdr, &elf_info); - if (ret) - return ret; - - elf_free_info(&elf_info); - - return elf_check_arch(&ehdr) ? 0 : -ENOEXEC; -} - /** * elf_exec_load - load ELF executable image * @lowest_load_addr: On return, will be the address where the first PT_LOAD @@ -518,16 +461,14 @@ static int elf64_probe(const char *buf, unsigned long len) * Return: * 0 on success, negative value on failure. */ -static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr, - struct elf_info *elf_info, - unsigned long *lowest_load_addr) +int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, + struct kexec_elf_info *elf_info, + struct kexec_buf *kbuf, + unsigned long *lowest_load_addr) { - unsigned long base = 0, lowest_addr = UINT_MAX; + unsigned long lowest_addr = UINT_MAX; int ret; size_t i; - struct kexec_buf kbuf = { .image = image, .buf_max = ppc64_rma_size, - .top_down = false }; - /* Read in the PT_LOAD segments. */ for (i = 0; i < ehdr->e_phnum; i++) { unsigned long load_addr; @@ -542,123 +483,58 @@ static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr, if (size > phdr->p_memsz) size = phdr->p_memsz; - kbuf.buffer = (void *) elf_info->buffer + phdr->p_offset; - kbuf.bufsz = size; - kbuf.memsz = phdr->p_memsz; - kbuf.buf_align = phdr->p_align; - kbuf.buf_min = phdr->p_paddr + base; - ret = kexec_add_buffer(&kbuf); + kbuf->buffer = (void *) elf_info->buffer + phdr->p_offset; + kbuf->bufsz = size; + kbuf->memsz = phdr->p_memsz; + kbuf->buf_align = phdr->p_align; + kbuf->buf_min = phdr->p_paddr; + kbuf->mem = KEXEC_BUF_MEM_UNKNOWN; + ret = kexec_add_buffer(kbuf); if (ret) goto out; - load_addr = kbuf.mem; + load_addr = kbuf->mem; if (load_addr < lowest_addr) lowest_addr = load_addr; } - /* Update entry point to reflect new load address. */ - ehdr->e_entry += base; - + image->start = ehdr->e_entry; *lowest_load_addr = lowest_addr; ret = 0; out: return ret; } -static void *elf64_load(struct kimage *image, char *kernel_buf, - unsigned long kernel_len, char *initrd, - unsigned long initrd_len, char *cmdline, - unsigned long cmdline_len) +int kexec_elf_kernel_load(struct kimage *image, struct kexec_buf *kbuf, + char *kernel_buf, unsigned long kernel_len, + unsigned long *kernel_load_addr) { int ret; - unsigned int fdt_size; - unsigned long kernel_load_addr; - unsigned long initrd_load_addr = 0, fdt_load_addr; - void *fdt; - const void *slave_code; struct elfhdr ehdr; - struct elf_info elf_info; - struct kexec_buf kbuf = { .image = image, .buf_min = 0, - .buf_max = ppc64_rma_size }; - struct kexec_buf pbuf = { .image = image, .buf_min = 0, - .buf_max = ppc64_rma_size, .top_down = true }; - - ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info); - if (ret) - goto out; + struct kexec_elf_info elf_info; - ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr); + ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info); if (ret) goto out; - pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr); - - ret = kexec_load_purgatory(image, &pbuf); - if (ret) { - pr_err("Loading purgatory failed.\n"); - goto out; - } - - pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem); - - if (initrd != NULL) { - kbuf.buffer = initrd; - kbuf.bufsz = kbuf.memsz = initrd_len; - kbuf.buf_align = PAGE_SIZE; - kbuf.top_down = false; - ret = kexec_add_buffer(&kbuf); - if (ret) - goto out; - initrd_load_addr = kbuf.mem; - - pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr); - } - - fdt_size = fdt_totalsize(initial_boot_params) * 2; - fdt = kmalloc(fdt_size, GFP_KERNEL); - if (!fdt) { - pr_err("Not enough memory for the device tree.\n"); - ret = -ENOMEM; - goto out; - } - ret = fdt_open_into(initial_boot_params, fdt, fdt_size); - if (ret < 0) { - pr_err("Error setting up the new device tree.\n"); - ret = -EINVAL; - goto out; - } - - ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline); - if (ret) - goto out; - - fdt_pack(fdt); + ret = kexec_elf_load(image, &ehdr, &elf_info, kbuf, kernel_load_addr); +out: + kexec_free_elf_info(&elf_info); + return ret; - kbuf.buffer = fdt; - kbuf.bufsz = kbuf.memsz = fdt_size; - kbuf.buf_align = PAGE_SIZE; - kbuf.top_down = true; - ret = kexec_add_buffer(&kbuf); - if (ret) - goto out; - fdt_load_addr = kbuf.mem; +} - pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr); +int kexec_elf_probe(const char *buf, unsigned long len) +{ + struct elfhdr ehdr; + struct kexec_elf_info elf_info; + int ret; - slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset; - ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr, - fdt_load_addr); + ret = kexec_build_elf_info(buf, len, &ehdr, &elf_info); if (ret) - pr_err("Error setting up the purgatory.\n"); + return ret; -out: - elf_free_info(&elf_info); + kexec_free_elf_info(&elf_info); - /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */ - return ret ? ERR_PTR(ret) : fdt; + return elf_check_arch(&ehdr) ? 0 : -ENOEXEC; } - -const struct kexec_file_ops kexec_elf64_ops = { - .probe = elf64_probe, - .load = elf64_load, -}; -- 2.13.3 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec