2 * Copyright (C) 2015 Imagination Technologies
3 * Author: Alex Smith <alex.smith@imgtec.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
11 static inline bool FUNC(patch_vdso)(const char *path, void *vdso)
13 const ELF(Ehdr) *ehdr = vdso;
16 char *shstrtab, *name;
17 uint16_t sh_count, sh_entsize, i;
19 shdrs = vdso + FUNC(swap_uint)(ehdr->e_shoff);
20 sh_count = swap_uint16(ehdr->e_shnum);
21 sh_entsize = swap_uint16(ehdr->e_shentsize);
23 shdr = shdrs + (sh_entsize * swap_uint16(ehdr->e_shstrndx));
24 shstrtab = vdso + FUNC(swap_uint)(shdr->sh_offset);
26 for (i = 0; i < sh_count; i++) {
27 shdr = shdrs + (i * sh_entsize);
28 name = shstrtab + swap_uint32(shdr->sh_name);
31 * Ensure there are no relocation sections - ld.so does not
32 * relocate the VDSO so if there are relocations things will
35 switch (swap_uint32(shdr->sh_type)) {
39 "%s: '%s' contains relocation sections\n",
44 /* Check for existing sections. */
45 if (strcmp(name, ".MIPS.abiflags") == 0) {
47 "%s: '%s' already contains a '.MIPS.abiflags' section\n",
52 if (strcmp(name, ".mips_abiflags") == 0) {
53 strcpy(name, ".MIPS.abiflags");
54 shdr->sh_type = swap_uint32(SHT_MIPS_ABIFLAGS);
55 shdr->sh_entsize = shdr->sh_size;
62 static inline bool FUNC(get_symbols)(const char *path, void *vdso)
64 const ELF(Ehdr) *ehdr = vdso;
69 uint16_t sh_count, sh_entsize, st_count, st_entsize, i, j;
73 shdrs = vdso + FUNC(swap_uint)(ehdr->e_shoff);
74 sh_count = swap_uint16(ehdr->e_shnum);
75 sh_entsize = swap_uint16(ehdr->e_shentsize);
77 for (i = 0; i < sh_count; i++) {
78 shdr = shdrs + (i * sh_entsize);
80 if (swap_uint32(shdr->sh_type) == SHT_SYMTAB)
85 fprintf(stderr, "%s: '%s' has no symbol table\n", program_name,
91 flags = swap_uint32(ehdr->e_flags);
92 if (elf_class == ELFCLASS64)
94 else if (flags & EF_MIPS_ABI2)
99 /* Get symbol table. */
100 symtab = vdso + FUNC(swap_uint)(shdr->sh_offset);
101 st_entsize = FUNC(swap_uint)(shdr->sh_entsize);
102 st_count = FUNC(swap_uint)(shdr->sh_size) / st_entsize;
104 /* Get string table. */
105 shdr = shdrs + (swap_uint32(shdr->sh_link) * sh_entsize);
106 strtab = vdso + FUNC(swap_uint)(shdr->sh_offset);
108 /* Write offsets for symbols needed by the kernel. */
109 for (i = 0; vdso_symbols[i].name; i++) {
110 if (!(vdso_symbols[i].abis & elf_abi))
113 for (j = 0; j < st_count; j++) {
114 sym = symtab + (j * st_entsize);
115 name = strtab + swap_uint32(sym->st_name);
117 if (!strcmp(name, vdso_symbols[i].name)) {
118 offset = FUNC(swap_uint)(sym->st_value);
121 "\t.%s = 0x%" PRIx64 ",\n",
122 vdso_symbols[i].offset_name, offset);
129 "%s: '%s' is missing required symbol '%s'\n",
130 program_name, path, vdso_symbols[i].name);