X-Git-Url: https://repo.jachan.dev/qemu.git/blobdiff_plain/8ce3c44c925982d834a8200ee0c9c00a7e9db20e..ed31504097cd038097a720efd82a69273c04cf61:/include/hw/elf_ops.h diff --git a/include/hw/elf_ops.h b/include/hw/elf_ops.h index a517753a6f..74679ff8da 100644 --- a/include/hw/elf_ops.h +++ b/include/hw/elf_ops.h @@ -49,6 +49,13 @@ static void glue(bswap_sym, SZ)(struct elf_sym *sym) bswap16s(&sym->st_shndx); } +static void glue(bswap_rela, SZ)(struct elf_rela *rela) +{ + bswapSZs(&rela->r_offset); + bswapSZs(&rela->r_info); + bswapSZs((elf_word *)&rela->r_addend); +} + static struct elf_shdr *glue(find_section, SZ)(struct elf_shdr *shdr_table, int n, int type) { @@ -98,7 +105,7 @@ static int glue(symcmp, SZ)(const void *s0, const void *s1) } static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab, - int clear_lsb) + int clear_lsb, symbol_fn_t sym_cb) { struct elf_shdr *symtab, *strtab, *shdr_table = NULL; struct elf_sym *syms = NULL; @@ -126,10 +133,26 @@ static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab, nsyms = symtab->sh_size / sizeof(struct elf_sym); + /* String table */ + if (symtab->sh_link >= ehdr->e_shnum) { + goto fail; + } + strtab = &shdr_table[symtab->sh_link]; + + str = load_at(fd, strtab->sh_offset, strtab->sh_size); + if (!str) { + goto fail; + } + i = 0; while (i < nsyms) { - if (must_swab) + if (must_swab) { glue(bswap_sym, SZ)(&syms[i]); + } + if (sym_cb) { + sym_cb(str + syms[i].st_name, syms[i].st_info, + syms[i].st_value, syms[i].st_size); + } /* We are only interested in function symbols. Throw everything else away. */ if (syms[i].st_shndx == SHN_UNDEF || @@ -156,15 +179,6 @@ static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab, } } - /* String table */ - if (symtab->sh_link >= ehdr->e_shnum) - goto fail; - strtab = &shdr_table[symtab->sh_link]; - - str = load_at(fd, strtab->sh_offset, strtab->sh_size); - if (!str) - goto fail; - /* Commit */ s = g_malloc0(sizeof(*s)); s->lookup_symbol = glue(lookup_symbol, SZ); @@ -182,12 +196,83 @@ static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab, return -1; } +static int glue(elf_reloc, SZ)(struct elfhdr *ehdr, int fd, int must_swab, + uint64_t (*translate_fn)(void *, uint64_t), + void *translate_opaque, uint8_t *data, + struct elf_phdr *ph, int elf_machine) +{ + struct elf_shdr *reltab, *shdr_table = NULL; + struct elf_rela *rels = NULL; + int nrels, i, ret = -1; + elf_word wordval; + void *addr; + + shdr_table = load_at(fd, ehdr->e_shoff, + sizeof(struct elf_shdr) * ehdr->e_shnum); + if (!shdr_table) { + return -1; + } + if (must_swab) { + for (i = 0; i < ehdr->e_shnum; i++) { + glue(bswap_shdr, SZ)(&shdr_table[i]); + } + } + + reltab = glue(find_section, SZ)(shdr_table, ehdr->e_shnum, SHT_RELA); + if (!reltab) { + goto fail; + } + rels = load_at(fd, reltab->sh_offset, reltab->sh_size); + if (!rels) { + goto fail; + } + nrels = reltab->sh_size / sizeof(struct elf_rela); + + for (i = 0; i < nrels; i++) { + if (must_swab) { + glue(bswap_rela, SZ)(&rels[i]); + } + if (rels[i].r_offset < ph->p_vaddr || + rels[i].r_offset >= ph->p_vaddr + ph->p_filesz) { + continue; + } + addr = &data[rels[i].r_offset - ph->p_vaddr]; + switch (elf_machine) { + case EM_S390: + switch (rels[i].r_info) { + case R_390_RELATIVE: + wordval = *(elf_word *)addr; + if (must_swab) { + bswapSZs(&wordval); + } + wordval = translate_fn(translate_opaque, wordval); + if (must_swab) { + bswapSZs(&wordval); + } + *(elf_word *)addr = wordval; + break; + default: + fprintf(stderr, "Unsupported relocation type %i!\n", + (int)rels[i].r_info); + } + } + } + + ret = 0; +fail: + g_free(rels); + g_free(shdr_table); + return ret; +} + static int glue(load_elf, SZ)(const char *name, int fd, uint64_t (*translate_fn)(void *, uint64_t), void *translate_opaque, int must_swab, uint64_t *pentry, uint64_t *lowaddr, uint64_t *highaddr, - int elf_machine, int clear_lsb) + int elf_machine, int clear_lsb, int data_swab, + AddressSpace *as, bool load_rom, + symbol_fn_t sym_cb) { struct elfhdr ehdr; struct elf_phdr *phdr = NULL, *ph; @@ -204,27 +289,51 @@ static int glue(load_elf, SZ)(const char *name, int fd, glue(bswap_ehdr, SZ)(&ehdr); } + if (elf_machine <= EM_NONE) { + /* The caller didn't specify an ARCH, we can figure it out */ + elf_machine = ehdr.e_machine; + } + switch (elf_machine) { case EM_PPC64: - if (EM_PPC64 != ehdr.e_machine) - if (EM_PPC != ehdr.e_machine) { + if (ehdr.e_machine != EM_PPC64) { + if (ehdr.e_machine != EM_PPC) { ret = ELF_LOAD_WRONG_ARCH; goto fail; } + } break; case EM_X86_64: - if (EM_X86_64 != ehdr.e_machine) - if (EM_386 != ehdr.e_machine) { + if (ehdr.e_machine != EM_X86_64) { + if (ehdr.e_machine != EM_386) { ret = ELF_LOAD_WRONG_ARCH; goto fail; } + } break; case EM_MICROBLAZE: - if (EM_MICROBLAZE != ehdr.e_machine) - if (EM_MICROBLAZE_OLD != ehdr.e_machine) { + if (ehdr.e_machine != EM_MICROBLAZE) { + if (ehdr.e_machine != EM_MICROBLAZE_OLD) { + ret = ELF_LOAD_WRONG_ARCH; + goto fail; + } + } + break; + case EM_MOXIE: + if (ehdr.e_machine != EM_MOXIE) { + if (ehdr.e_machine != EM_MOXIE_OLD) { ret = ELF_LOAD_WRONG_ARCH; goto fail; } + } + break; + case EM_MIPS: + case EM_NANOMIPS: + if ((ehdr.e_machine != EM_MIPS) && + (ehdr.e_machine != EM_NANOMIPS)) { + ret = ELF_LOAD_WRONG_ARCH; + goto fail; + } break; default: if (elf_machine != ehdr.e_machine) { @@ -236,10 +345,12 @@ static int glue(load_elf, SZ)(const char *name, int fd, if (pentry) *pentry = (uint64_t)(elf_sword)ehdr.e_entry; - glue(load_symbols, SZ)(&ehdr, fd, must_swab, clear_lsb); + glue(load_symbols, SZ)(&ehdr, fd, must_swab, clear_lsb, sym_cb); size = ehdr.e_phnum * sizeof(phdr[0]); - lseek(fd, ehdr.e_phoff, SEEK_SET); + if (lseek(fd, ehdr.e_phoff, SEEK_SET) != ehdr.e_phoff) { + goto fail; + } phdr = g_malloc0(size); if (!phdr) goto fail; @@ -267,14 +378,84 @@ static int glue(load_elf, SZ)(const char *name, int fd, goto fail; } } + + /* The ELF spec is somewhat vague about the purpose of the + * physical address field. One common use in the embedded world + * is that physical address field specifies the load address + * and the virtual address field specifies the execution address. + * Segments are packed into ROM or flash, and the relocation + * and zero-initialization of data is done at runtime. This + * means that the memsz header represents the runtime size of the + * segment, but the filesz represents the loadtime size. If + * we try to honour the memsz value for an ELF file like this + * we will end up with overlapping segments (which the + * loader.c code will later reject). + * We support ELF files using this scheme by by checking whether + * paddr + memsz for this segment would overlap with any other + * segment. If so, then we assume it's using this scheme and + * truncate the loaded segment to the filesz size. + * If the segment considered as being memsz size doesn't overlap + * then we use memsz for the segment length, to handle ELF files + * which assume that the loader will do the zero-initialization. + */ + if (mem_size > file_size) { + /* If this segment's zero-init portion overlaps another + * segment's data or zero-init portion, then truncate this one. + * Invalid ELF files where the segments overlap even when + * only file_size bytes are loaded will be rejected by + * the ROM overlap check in loader.c, so we don't try to + * explicitly detect those here. + */ + int j; + elf_word zero_start = ph->p_paddr + file_size; + elf_word zero_end = ph->p_paddr + mem_size; + + for (j = 0; j < ehdr.e_phnum; j++) { + struct elf_phdr *jph = &phdr[j]; + + if (i != j && jph->p_type == PT_LOAD) { + elf_word other_start = jph->p_paddr; + elf_word other_end = jph->p_paddr + jph->p_memsz; + + if (!(other_start >= zero_end || + zero_start >= other_end)) { + mem_size = file_size; + break; + } + } + } + } + /* address_offset is hack for kernel images that are linked at the wrong physical address. */ if (translate_fn) { addr = translate_fn(translate_opaque, ph->p_paddr); + glue(elf_reloc, SZ)(&ehdr, fd, must_swab, translate_fn, + translate_opaque, data, ph, elf_machine); } else { addr = ph->p_paddr; } + if (data_swab) { + int j; + for (j = 0; j < file_size; j += (1 << data_swab)) { + uint8_t *dp = data + j; + switch (data_swab) { + case (1): + *(uint16_t *)dp = bswap16(*(uint16_t *)dp); + break; + case (2): + *(uint32_t *)dp = bswap32(*(uint32_t *)dp); + break; + case (3): + *(uint64_t *)dp = bswap64(*(uint64_t *)dp); + break; + default: + g_assert_not_reached(); + } + } + } + /* the entry pointer in the ELF header is a virtual * address, if the text segments paddr and vaddr differ * we need to adjust the entry */ @@ -286,10 +467,27 @@ static int glue(load_elf, SZ)(const char *name, int fd, *pentry = ehdr.e_entry - ph->p_vaddr + ph->p_paddr; } - snprintf(label, sizeof(label), "phdr #%d: %s", i, name); + if (mem_size == 0) { + /* Some ELF files really do have segments of zero size; + * just ignore them rather than trying to create empty + * ROM blobs, because the zero-length blob can falsely + * trigger the overlapping-ROM-blobs check. + */ + g_free(data); + } else { + if (load_rom) { + snprintf(label, sizeof(label), "phdr #%d: %s", i, name); - /* rom_add_elf_program() seize the ownership of 'data' */ - rom_add_elf_program(label, data, file_size, mem_size, addr); + /* rom_add_elf_program() seize the ownership of 'data' */ + rom_add_elf_program(label, data, file_size, mem_size, + addr, as); + } else { + address_space_write(as ? as : &address_space_memory, + addr, MEMTXATTRS_UNSPECIFIED, + data, file_size); + g_free(data); + } + } total_size += mem_size; if (addr < low)