diff options
Diffstat (limited to 'common/elf.c')
-rw-r--r-- | common/elf.c | 281 |
1 files changed, 241 insertions, 40 deletions
diff --git a/common/elf.c b/common/elf.c index 4733accb05..62f793010f 100644 --- a/common/elf.c +++ b/common/elf.c @@ -5,21 +5,32 @@ #include <common.h> #include <elf.h> +#include <errno.h> +#include <fcntl.h> +#include <libfile.h> #include <memory.h> +#include <unistd.h> +#include <zero_page.h> +#include <linux/fs.h> +#include <linux/list_sort.h> struct elf_section { struct list_head list; struct resource *r; + void *phdr; }; static int elf_request_region(struct elf_image *elf, resource_size_t start, - resource_size_t size) + resource_size_t size, void *phdr) { struct list_head *list = &elf->list; struct resource *r_new; struct elf_section *r; - r = xzalloc(sizeof(*r)); + r = calloc(1, sizeof(*r)); + if (!r) + return -ENOMEM; + r_new = request_sdram_region("elf_section", start, size); if (!r_new) { pr_err("Failed to request region: %pa %pa\n", &start, &size); @@ -27,6 +38,7 @@ static int elf_request_region(struct elf_image *elf, resource_size_t start, } r->r = r_new; + r->phdr = phdr; list_add_tail(&r->list, list); return 0; @@ -39,108 +51,297 @@ static void elf_release_regions(struct elf_image *elf) list_for_each_entry_safe(r, r_tmp, list, list) { release_sdram_region(r->r); + list_del(&r->list); free(r); } } - -static int load_elf_phdr_segment(struct elf_image *elf, void *src, - void *phdr) +static int request_elf_segment(struct elf_image *elf, void *phdr) { - void *dst = (void *) elf_phdr_p_paddr(elf, phdr); + void *dst = (void *) (phys_addr_t) elf_phdr_p_paddr(elf, phdr); int ret; - u64 p_filesz = elf_phdr_p_filesz(elf, phdr); u64 p_memsz = elf_phdr_p_memsz(elf, phdr); /* we care only about PT_LOAD segments */ if (elf_phdr_p_type(elf, phdr) != PT_LOAD) return 0; - if (!p_filesz) + if (!p_memsz) return 0; - pr_debug("Loading phdr to 0x%p (%llu bytes)\n", dst, p_filesz); + if (dst < elf->low_addr) + elf->low_addr = dst; + if (dst + p_memsz > elf->high_addr) + elf->high_addr = dst + p_memsz; + + pr_debug("Requesting segment 0x%p (%llu bytes)\n", dst, p_memsz); - ret = elf_request_region(elf, (resource_size_t)dst, p_filesz); + ret = elf_request_region(elf, (resource_size_t)dst, p_memsz, phdr); if (ret) return ret; - memcpy(dst, src, p_filesz); + return 0; +} + +static int elf_section_cmp(void *priv, struct list_head *a, struct list_head *b) +{ + struct elf_image *elf = priv; + struct elf_section *elf_a, *elf_b; - if (p_filesz < p_memsz) - memset(dst + p_filesz, 0x00, - p_memsz - p_filesz); + if (a == b) + return 0; - return 0; + elf_a = list_entry(a, struct elf_section, list); + elf_b = list_entry(b, struct elf_section, list); + + return elf_phdr_p_offset(elf, elf_a->phdr) > + elf_phdr_p_offset(elf, elf_b->phdr); +} + +static int load_elf_to_memory(struct elf_image *elf) +{ + void *dst; + int ret = 0, fd = -1; + u64 p_filesz, p_memsz, p_offset; + struct elf_section *r; + struct list_head *list = &elf->list; + + if (elf->filename) { + fd = open(elf->filename, O_RDONLY); + if (fd < 0) { + pr_err("could not open: %m\n"); + return -errno; + } + } + + zero_page_access(); + + list_for_each_entry(r, list, list) { + p_offset = elf_phdr_p_offset(elf, r->phdr); + p_filesz = elf_phdr_p_filesz(elf, r->phdr); + p_memsz = elf_phdr_p_memsz(elf, r->phdr); + dst = (void *) (phys_addr_t) elf_phdr_p_paddr(elf, r->phdr); + + pr_debug("Loading phdr offset 0x%llx to 0x%p (%llu bytes)\n", + p_offset, dst, p_filesz); + + if (fd >= 0) { + ret = lseek(fd, p_offset, SEEK_SET); + if (ret == -1) { + pr_err("lseek at offset 0x%llx failed\n", + p_offset); + goto out; + } + + if (read_full(fd, dst, p_filesz) < 0) { + pr_err("could not read elf segment: %m\n"); + ret = -errno; + goto out; + } + } else { + memcpy(dst, elf->hdr_buf + p_offset, p_filesz); + } + + if (p_filesz < p_memsz) + memset(dst + p_filesz, 0x00, p_memsz - p_filesz); + } + +out: + zero_page_faulting(); + + close(fd); + + return ret >= 0 ? 0 : ret; } -static int load_elf_image_phdr(struct elf_image *elf) +static int load_elf_image_segments(struct elf_image *elf) { - void *buf = elf->buf; + void *buf = elf->hdr_buf; void *phdr = (void *) (buf + elf_hdr_e_phoff(elf, buf)); int i, ret; - elf->entry = elf_hdr_e_entry(elf, buf); + /* File as already been loaded */ + if (!list_empty(&elf->list)) + return -EINVAL; for (i = 0; i < elf_hdr_e_phnum(elf, buf) ; ++i) { - void *src = buf + elf_phdr_p_offset(elf, phdr); - - ret = load_elf_phdr_segment(elf, src, phdr); - /* in case of error elf_load_image() caller should clean up and - * call elf_release_image() */ + ret = request_elf_segment(elf, phdr); if (ret) - return ret; + goto elf_release_regions; phdr += elf_size_of_phdr(elf); } + /* + * Sort the list to avoid doing backward lseek while loading the elf + * segments from file to memory(some filesystems don't support it) + */ + list_sort(elf, &elf->list, elf_section_cmp); + + ret = load_elf_to_memory(elf); + if (ret) + goto elf_release_regions; + return 0; + +elf_release_regions: + elf_release_regions(elf); + + return ret; } -static int elf_check_image(struct elf_image *elf) +static int elf_check_image(struct elf_image *elf, void *buf) { - if (strncmp(elf->buf, ELFMAG, SELFMAG)) { + if (strncmp(buf, ELFMAG, SELFMAG)) { pr_err("ELF magic not found.\n"); return -EINVAL; } - elf->class = ((char *) elf->buf)[EI_CLASS]; + elf->class = ((char *) buf)[EI_CLASS]; - if (elf_hdr_e_type(elf, elf->buf) != ET_EXEC) { + if (elf_hdr_e_type(elf, buf) != ET_EXEC) { pr_err("Non EXEC ELF image.\n"); return -ENOEXEC; } + if (!elf_hdr_e_phnum(elf, buf)) { + pr_err("No phdr found.\n"); + return -ENOEXEC; + } + return 0; } -struct elf_image *elf_load_image(void *buf) +static void elf_init_struct(struct elf_image *elf) +{ + INIT_LIST_HEAD(&elf->list); + elf->low_addr = (void *) (unsigned long) -1; + elf->high_addr = 0; + elf->filename = NULL; +} + +struct elf_image *elf_open_binary(void *buf) { - struct elf_image *elf; int ret; + struct elf_image *elf; - elf = xzalloc(sizeof(*elf)); + elf = calloc(1, sizeof(*elf)); + if (!elf) + return ERR_PTR(-ENOMEM); - INIT_LIST_HEAD(&elf->list); + elf_init_struct(elf); + + elf->hdr_buf = buf; + ret = elf_check_image(elf, buf); + if (ret) { + free(elf); + return ERR_PTR(-EINVAL); + } - elf->buf = buf; + elf->entry = elf_hdr_e_entry(elf, elf->hdr_buf); - ret = elf_check_image(elf); + return elf; +} + +static struct elf_image *elf_check_init(const char *filename) +{ + int ret, fd; + int hdr_size; + struct elf64_hdr hdr; + struct elf_image *elf; + + elf = calloc(1, sizeof(*elf)); + if (!elf) + return ERR_PTR(-ENOMEM); + + elf_init_struct(elf); + + /* First pass is to read elf header only */ + fd = open(filename, O_RDONLY); + if (fd < 0) { + pr_err("could not open: %m\n"); + ret = -errno; + goto err_free_elf; + } + + if (read_full(fd, &hdr, sizeof(hdr)) < 0) { + pr_err("could not read elf header: %m\n"); + close(fd); + ret = -errno; + goto err_free_elf; + } + close(fd); + + ret = elf_check_image(elf, &hdr); if (ret) - return ERR_PTR(ret); + goto err_free_elf; - ret = load_elf_image_phdr(elf); - if (ret) { - elf_release_image(elf); - return ERR_PTR(ret); + hdr_size = elf_hdr_e_phoff(elf, &hdr) + + elf_hdr_e_phnum(elf, &hdr) * + elf_hdr_e_phentsize(elf, &hdr); + + /* Second pass is to read the whole elf header and program headers */ + elf->hdr_buf = malloc(hdr_size); + if (!elf->hdr_buf) { + ret = -ENOMEM; + goto err_free_elf; } + /* + * We must open the file again since some fs (tftp) do not support + * backward lseek operations + */ + fd = open(filename, O_RDONLY); + if (fd < 0) { + pr_err("could not open: %m\n"); + ret = -errno; + goto err_free_hdr_buf; + } + + if (read_full(fd, elf->hdr_buf, hdr_size) < 0) { + pr_err("could not read elf program headers: %m\n"); + ret = -errno; + close(fd); + goto err_free_hdr_buf; + } + close(fd); + + elf->filename = strdup(filename); + if (!elf->filename) { + ret = -ENOMEM; + goto err_free_hdr_buf; + } + + elf->entry = elf_hdr_e_entry(elf, elf->hdr_buf); + return elf; + +err_free_hdr_buf: + free(elf->hdr_buf); +err_free_elf: + free(elf); + + return ERR_PTR(ret); } -void elf_release_image(struct elf_image *elf) +struct elf_image *elf_open(const char *filename) +{ + return elf_check_init(filename); +} + +int elf_load(struct elf_image *elf) +{ + return load_elf_image_segments(elf); +} + +void elf_close(struct elf_image *elf) { elf_release_regions(elf); + if (elf->filename) { + free(elf->hdr_buf); + free(elf->filename); + } + free(elf); } |