📄 module.c
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#include <linux/moduleloader.h>#include <linux/elf.h>#include <linux/vmalloc.h>#include <linux/fs.h>#include <linux/string.h>#include <linux/kernel.h>#if 0#define DEBUGP printk#else#define DEBUGP(fmt...)#endifvoid *module_alloc(unsigned long size){ if (size == 0) return NULL; return vmalloc(size);}/* Free memory returned from module_alloc */void module_free(struct module *mod, void *module_region){ vfree(module_region); /* FIXME: If module_region == mod->init_region, trim exception table entries. */}/* We don't need anything special. */int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, char *secstrings, struct module *mod){ return 0;}int apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relsec, struct module *me){ unsigned int i; Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr; Elf32_Sym *sym; uint32_t *location; DEBUGP("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. Note that all undefined symbols have been resolved. */ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + ELF32_R_SYM(rel[i].r_info); switch (ELF32_R_TYPE(rel[i].r_info)) { case R_68K_32: /* We add the value into the location given */ *location += sym->st_value; break; case R_68K_PC32: /* Add the value, subtract its postition */ *location += sym->st_value - (uint32_t)location; break; default: printk(KERN_ERR "module %s: Unknown relocation: %u\n", me->name, ELF32_R_TYPE(rel[i].r_info)); return -ENOEXEC; } } return 0;}int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relsec, struct module *me){ unsigned int i; Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; Elf32_Sym *sym; uint32_t *location; DEBUGP("Applying relocate_add 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. Note that all undefined symbols have been resolved. */ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + ELF32_R_SYM(rel[i].r_info); switch (ELF32_R_TYPE(rel[i].r_info)) { case R_68K_32: /* We add the value into the location given */ *location = rel[i].r_addend + sym->st_value; break; case R_68K_PC32: /* Add the value, subtract its postition */ *location = rel[i].r_addend + sym->st_value - (uint32_t)location; break; default: printk(KERN_ERR "module %s: Unknown relocation: %u\n", me->name, ELF32_R_TYPE(rel[i].r_info)); return -ENOEXEC; } } return 0;}int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *me){ return 0;}void module_arch_cleanup(struct module *mod){}
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