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;
}
/**
* 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;
}
/**
* 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;
}
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 i, ret;
unsigned int fdt_size;
unsigned long kernel_load_addr, purgatory_load_addr;
unsigned long initrd_load_addr, fdt_load_addr, stack_top;
void *fdt;
const void *slave_code;
struct elfhdr ehdr;
struct elf_info elf_info;
struct fdt_reserve_entry *rsvmap;
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ppc64_rma_size };
ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
if (ret)
goto out;
ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr);
if (ret)
goto out;
pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
ret = kexec_load_purgatory(image, 0, ppc64_rma_size, true,
&purgatory_load_addr);
if (ret) {
pr_err("Loading purgatory failed.\n");
goto out;
}
pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr);
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;
/*
* Documentation/devicetree/booting-without-of.txt says we need to
* add a reservation entry for the device tree block, but
* early_init_fdt_reserve_self reserves the memory even if there's no
* such entry. We'll add a reservation entry anyway, to be safe and
* compliant.
*
* Use dummy values, we will correct them in a moment.
*/
ret = fdt_add_mem_rsv(fdt, 1, 1);
if (ret) {
pr_err("Error reserving device tree memory: %s\n",
fdt_strerror(ret));
ret = -EINVAL;
goto out;
}
fdt_pack(fdt);
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;
/*
* Fix fdt reservation, now that we now where it will be loaded
* and how big it is.
*/
rsvmap = fdt + fdt_off_mem_rsvmap(fdt);
i = fdt_num_mem_rsv(fdt) - 1;
rsvmap[i].address = cpu_to_fdt64(fdt_load_addr);
rsvmap[i].size = cpu_to_fdt64(fdt_totalsize(fdt));
pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
kbuf.memsz = PURGATORY_STACK_SIZE;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = true;
ret = kexec_locate_mem_hole(&kbuf);
if (ret) {
pr_err("Couldn't find free memory for the purgatory stack.\n");
ret = -ENOMEM;
goto out;
}
stack_top = kbuf.mem + PURGATORY_STACK_SIZE - 1;
pr_debug("Purgatory stack is at 0x%lx\n", stack_top);
slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
fdt_load_addr, stack_top,
find_debug_console(fdt));
if (ret)
pr_err("Error setting up the purgatory.\n");
out:
elf_free_info(&elf_info);
/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
return ret ? ERR_PTR(ret) : fdt;
}
struct kexec_file_ops kexec_elf64_ops = {
.probe = elf64_probe,
.load = elf64_load,
};
/**
* 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;
}
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 ret;
unsigned int fdt_size;
unsigned long kernel_load_addr, purgatory_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 };
ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
if (ret)
goto out;
ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr);
if (ret)
goto out;
pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
ret = kexec_load_purgatory(image, 0, ppc64_rma_size, true,
&purgatory_load_addr);
if (ret) {
pr_err("Loading purgatory failed.\n");
goto out;
}
pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr);
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(fdt, initrd_load_addr, initrd_len, cmdline);
if (ret)
goto out;
fdt_pack(fdt);
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);
slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
fdt_load_addr);
if (ret)
pr_err("Error setting up the purgatory.\n");
out:
elf_free_info(&elf_info);
/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
return ret ? ERR_PTR(ret) : fdt;
}
struct kexec_file_ops kexec_elf64_ops = {
.probe = elf64_probe,
.load = elf64_load,
};