arch/h8300/kernel/module.c

   1 #include <linux/moduleloader.h>
   2 #include <linux/elf.h>
   3 #include <linux/vmalloc.h>
   4 #include <linux/fs.h>
   5 #include <linux/string.h>
   6 #include <linux/kernel.h>
   7
   8 int apply_relocate_add(Elf32_Shdr *sechdrs,
   9                        const char *strtab,
  10                        unsigned int symindex,
  11                        unsigned int relsec,
  12                        struct module *me)
  13 {
  14         unsigned int i;
  15         Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
  16
  17         pr_debug("Applying relocate section %u to %u\n", relsec,
  18                sechdrs[relsec].sh_info);
  19         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
  20                 /* This is where to make the change */
  21                 uint32_t *loc =
  22                         (uint32_t *)(sechdrs[sechdrs[relsec].sh_info].sh_addr
  23                                              + rela[i].r_offset);
  24                 /* This is the symbol it is referring to.  Note that all
  25                    undefined symbols have been resolved.  */
  26                 Elf32_Sym *sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
  27                         + ELF32_R_SYM(rela[i].r_info);
  28                 uint32_t v = sym->st_value + rela[i].r_addend;
  29
  30                 switch (ELF32_R_TYPE(rela[i].r_info)) {
  31                 case R_H8_DIR24R8:
  32                         loc = (uint32_t *)((uint32_t)loc - 1);
  33                         *loc = (*loc & 0xff000000) | ((*loc & 0xffffff) + v);
  34                         break;
  35                 case R_H8_DIR24A8:
  36                         if (ELF32_R_SYM(rela[i].r_info))
  37                                 *loc += v;
  38                         break;
  39                 case R_H8_DIR32:
  40                 case R_H8_DIR32A16:
  41                         *loc += v;
  42                         break;
  43                 case R_H8_PCREL16:
  44                         v -= (unsigned long)loc + 2;
  45                         if ((Elf32_Sword)v > 0x7fff ||
  46                             (Elf32_Sword)v < -(Elf32_Sword)0x8000)
  47                                 goto overflow;
  48                         else
  49                                 *(unsigned short *)loc = v;
  50                         break;
  51                 case R_H8_PCREL8:
  52                         v -= (unsigned long)loc + 1;
  53                         if ((Elf32_Sword)v > 0x7f ||
  54                             (Elf32_Sword)v < -(Elf32_Sword)0x80)
  55                                 goto overflow;
  56                         else
  57                                 *(unsigned char *)loc = v;
  58                         break;
  59                 default:
  60                         pr_err("module %s: Unknown relocation: %u\n",
  61                                me->name, ELF32_R_TYPE(rela[i].r_info));
  62                         return -ENOEXEC;
  63                 }
  64         }
  65         return 0;
  66  overflow:
  67         pr_err("module %s: relocation offset overflow: %08x\n",
  68                me->name, rela[i].r_offset);
  69         return -ENOEXEC;
  70 }