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-rw-r--r--arch/x86/kernel/module.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 1ea42d08349..b92fbcf4860 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -34,6 +34,32 @@
#define DEBUGP(fmt...)
#endif
+#if defined(CONFIG_UML) || defined(CONFIG_X86_32)
+void *module_alloc(unsigned long size)
+{
+ if (size == 0)
+ return NULL;
+ return vmalloc_exec(size);
+}
+#else /*X86_64*/
+void *module_alloc(unsigned long size)
+{
+ struct vm_struct *area;
+
+ if (!size)
+ return NULL;
+ size = PAGE_ALIGN(size);
+ if (size > MODULES_LEN)
+ return NULL;
+
+ area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
+ if (!area)
+ return NULL;
+
+ return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
+}
+#endif
+
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
@@ -51,6 +77,140 @@ int module_frob_arch_sections(Elf_Ehdr *hdr,
return 0;
}
+#ifdef CONFIG_X86_32
+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_386_32:
+ /* We add the value into the location given */
+ *location += sym->st_value;
+ break;
+ case R_386_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)
+{
+ printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
+ me->name);
+ return -ENOEXEC;
+}
+#else /*X86_64*/
+int apply_relocate_add(Elf64_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ unsigned int i;
+ Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
+ Elf64_Sym *sym;
+ void *loc;
+ u64 val;
+
+ 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 */
+ loc = (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 = (Elf64_Sym *)sechdrs[symindex].sh_addr
+ + ELF64_R_SYM(rel[i].r_info);
+
+ DEBUGP("type %d st_value %Lx r_addend %Lx loc %Lx\n",
+ (int)ELF64_R_TYPE(rel[i].r_info),
+ sym->st_value, rel[i].r_addend, (u64)loc);
+
+ val = sym->st_value + rel[i].r_addend;
+
+ switch (ELF64_R_TYPE(rel[i].r_info)) {
+ case R_X86_64_NONE:
+ break;
+ case R_X86_64_64:
+ *(u64 *)loc = val;
+ break;
+ case R_X86_64_32:
+ *(u32 *)loc = val;
+ if (val != *(u32 *)loc)
+ goto overflow;
+ break;
+ case R_X86_64_32S:
+ *(s32 *)loc = val;
+ if ((s64)val != *(s32 *)loc)
+ goto overflow;
+ break;
+ case R_X86_64_PC32:
+ val -= (u64)loc;
+ *(u32 *)loc = val;
+#if 0
+ if ((s64)val != *(s32 *)loc)
+ goto overflow;
+#endif
+ break;
+ default:
+ printk(KERN_ERR "module %s: Unknown rela relocation: %llu\n",
+ me->name, ELF64_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
+ }
+ return 0;
+
+overflow:
+ printk(KERN_ERR "overflow in relocation type %d val %Lx\n",
+ (int)ELF64_R_TYPE(rel[i].r_info), val);
+ printk(KERN_ERR "`%s' likely not compiled with -mcmodel=kernel\n",
+ me->name);
+ return -ENOEXEC;
+}
+
+int apply_relocate(Elf_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ printk(KERN_ERR "non add relocation not supported\n");
+ return -ENOSYS;
+}
+
+#endif
+
int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *me)