122 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <linux/moduleloader.h>
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| #include <linux/elf.h>
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| #include <linux/vmalloc.h>
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| #include <linux/fs.h>
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| #include <linux/string.h>
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| #include <linux/kernel.h>
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| 
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| #if 0
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| #define DEBUGP printk
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| #else
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| #define DEBUGP(fmt...)
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| #endif
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| 
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| void *module_alloc(unsigned long size)
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| {
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| 	if (size == 0)
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| 		return NULL;
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| 	return vmalloc(size);
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| }
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| 
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| 
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| /* Free memory returned from module_alloc */
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| void module_free(struct module *mod, void *module_region)
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| {
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| 	vfree(module_region);
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| }
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| 
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| /* We don't need anything special. */
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| int module_frob_arch_sections(Elf_Ehdr *hdr,
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| 			      Elf_Shdr *sechdrs,
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| 			      char *secstrings,
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| 			      struct module *mod)
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| {
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| 	return 0;
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| }
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| 
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| int apply_relocate(Elf32_Shdr *sechdrs,
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| 		   const char *strtab,
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| 		   unsigned int symindex,
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| 		   unsigned int relsec,
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| 		   struct module *me)
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| {
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| 	printk(KERN_ERR "module %s: RELOCATION unsupported\n",
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| 	       me->name);
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| 	return -ENOEXEC;
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| }
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| 
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| int apply_relocate_add(Elf32_Shdr *sechdrs,
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| 		       const char *strtab,
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| 		       unsigned int symindex,
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| 		       unsigned int relsec,
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| 		       struct module *me)
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| {
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| 	unsigned int i;
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| 	Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
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| 
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| 	DEBUGP("Applying relocate section %u to %u\n", relsec,
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| 	       sechdrs[relsec].sh_info);
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| 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
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| 		/* This is where to make the change */
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| 		uint32_t *loc = (uint32_t *)(sechdrs[sechdrs[relsec].sh_info].sh_addr
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| 					     + rela[i].r_offset);
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| 		/* This is the symbol it is referring to.  Note that all
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| 		   undefined symbols have been resolved.  */
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| 		Elf32_Sym *sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
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| 			+ ELF32_R_SYM(rela[i].r_info);
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| 		uint32_t v = sym->st_value + rela[i].r_addend;
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| 
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| 		switch (ELF32_R_TYPE(rela[i].r_info)) {
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| 		case R_H8_DIR24R8:
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| 			loc = (uint32_t *)((uint32_t)loc - 1);
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| 			*loc = (*loc & 0xff000000) | ((*loc & 0xffffff) + v);
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| 			break;
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| 		case R_H8_DIR24A8:
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| 			if (ELF32_R_SYM(rela[i].r_info))
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| 				*loc += v;
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| 			break;
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| 		case R_H8_DIR32:
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| 		case R_H8_DIR32A16:
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| 			*loc += v;
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| 			break;
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| 		case R_H8_PCREL16:
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| 			v -= (unsigned long)loc + 2;
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| 			if ((Elf32_Sword)v > 0x7fff || 
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| 			    (Elf32_Sword)v < -(Elf32_Sword)0x8000)
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| 				goto overflow;
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| 			else 
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| 				*(unsigned short *)loc = v;
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| 			break;
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| 		case R_H8_PCREL8:
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| 			v -= (unsigned long)loc + 1;
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| 			if ((Elf32_Sword)v > 0x7f || 
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| 			    (Elf32_Sword)v < -(Elf32_Sword)0x80)
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| 				goto overflow;
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| 			else 
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| 				*(unsigned char *)loc = v;
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| 			break;
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| 		default:
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| 			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
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| 			       me->name, ELF32_R_TYPE(rela[i].r_info));
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| 			return -ENOEXEC;
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| 		}
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| 	}
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| 	return 0;
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|  overflow:
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| 	printk(KERN_ERR "module %s: relocation offset overflow: %08x\n",
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| 	       me->name, rela[i].r_offset);
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| 	return -ENOEXEC;
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| }
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| 
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| int module_finalize(const Elf_Ehdr *hdr,
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| 		    const Elf_Shdr *sechdrs,
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| 		    struct module *me)
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| {
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| 	return module_bug_finalize(hdr, sechdrs, me);
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| }
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| 
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| void module_arch_cleanup(struct module *mod)
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| {
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| 	module_bug_cleanup(mod);
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| }
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