diff options
Diffstat (limited to 'arch/mips/kernel/module-rela.c')
| -rw-r--r-- | arch/mips/kernel/module-rela.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/mips/kernel/module-rela.c b/arch/mips/kernel/module-rela.c new file mode 100644 index 0000000..61d6002 --- /dev/null +++ b/arch/mips/kernel/module-rela.c @@ -0,0 +1,145 @@ +/* + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Copyright (C) 2001 Rusty Russell. + * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org) + * Copyright (C) 2005 Thiemo Seufer + */ + +#include <linux/elf.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/moduleloader.h> + +extern int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v); + +static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = v; + + return 0; +} + +static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v) +{ + if (v % 4) { + pr_err("module %s: dangerous R_MIPS_26 RELArelocation\n", + me->name); + return -ENOEXEC; + } + + if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) { + printk(KERN_ERR + "module %s: relocation overflow\n", + me->name); + return -ENOEXEC; + } + + *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff); + + return 0; +} + +static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x8000LL) >> 16) & 0xffff); + + return 0; +} + +static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *location = (*location & 0xffff0000) | (v & 0xffff); + + return 0; +} + +static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(Elf_Addr *)location = v; + + return 0; +} + +static int apply_r_mips_higher_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x80008000LL) >> 32) & 0xffff); + + return 0; +} + +static int apply_r_mips_highest_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *location = (*location & 0xffff0000) | + ((((long long) v + 0x800080008000LL) >> 48) & 0xffff); + + return 0; +} + +static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, + Elf_Addr v) = { + [R_MIPS_NONE] = apply_r_mips_none, + [R_MIPS_32] = apply_r_mips_32_rela, + [R_MIPS_26] = apply_r_mips_26_rela, + [R_MIPS_HI16] = apply_r_mips_hi16_rela, + [R_MIPS_LO16] = apply_r_mips_lo16_rela, + [R_MIPS_64] = apply_r_mips_64_rela, + [R_MIPS_HIGHER] = apply_r_mips_higher_rela, + [R_MIPS_HIGHEST] = apply_r_mips_highest_rela +}; + +int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr; + Elf_Sym *sym; + u32 *location; + unsigned int i; + Elf_Addr v; + int res; + + pr_debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset; + /* This is the symbol it is referring to */ + sym = (Elf_Sym *)sechdrs[symindex].sh_addr + + ELF_MIPS_R_SYM(rel[i]); + if (IS_ERR_VALUE(sym->st_value)) { + /* Ignore unresolved weak symbol */ + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) + continue; + printk(KERN_WARNING "%s: Unknown symbol %s\n", + me->name, strtab + sym->st_name); + return -ENOENT; + } + + v = sym->st_value + rel[i].r_addend; + + res = reloc_handlers_rela[ELF_MIPS_R_TYPE(rel[i])](me, location, v); + if (res) + return res; + } + + return 0; +} |