Commit d1a85305 authored by Bernd Schmidt's avatar Bernd Schmidt Committed by Bryan Wu
Browse files

Blackfin arch: Remove all traces of the relocation stack 



Remove all traces of the relocation stack.  It's been removed from
binutils for years now.

Add a sanity overflow check to pcrel24 relocations to catch modules that
were built without -mlong-calls.

Signed-off-by: default avatarBernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: default avatarBryan Wu <cooloney@kernel.org>
parent 2eddbada

arch/blackfin/kernel/module.c

+7 −132
Original line number Diff line number Diff line
@@ -37,111 +37,6 @@ 
#include <asm/dma.h>

#include <asm/cacheflush.h>



/*

 * handle arithmetic relocations.

 * See binutils/bfd/elf32-bfin.c for more details

 */

#define RELOC_STACK_SIZE 100

static uint32_t reloc_stack[RELOC_STACK_SIZE];

static unsigned int reloc_stack_tos;



#define is_reloc_stack_empty() ((reloc_stack_tos > 0)?0:1)



static void reloc_stack_push(uint32_t value)

{

	reloc_stack[reloc_stack_tos++] = value;

}



static uint32_t reloc_stack_pop(void)

{

	return reloc_stack[--reloc_stack_tos];

}



static uint32_t reloc_stack_operate(unsigned int oper, struct module *mod)

{

	uint32_t value;



	switch (oper) {

	case R_add:

		value = reloc_stack[reloc_stack_tos - 2] +

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_sub:

		value = reloc_stack[reloc_stack_tos - 2] -

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_mult:

		value = reloc_stack[reloc_stack_tos - 2] *

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_div:

		value = reloc_stack[reloc_stack_tos - 2] /

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_mod:

		value = reloc_stack[reloc_stack_tos - 2] %

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_lshift:

		value = reloc_stack[reloc_stack_tos - 2] <<

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_rshift:

		value = reloc_stack[reloc_stack_tos - 2] >>

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_and:

		value = reloc_stack[reloc_stack_tos - 2] &

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_or:

		value = reloc_stack[reloc_stack_tos - 2] |

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_xor:

		value = reloc_stack[reloc_stack_tos - 2] ^

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_land:

		value = reloc_stack[reloc_stack_tos - 2] &&

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_lor:

		value = reloc_stack[reloc_stack_tos - 2] ||

			reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 2;

		break;

	case R_neg:

		value = -reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos--;

		break;

	case R_comp:

		value = ~reloc_stack[reloc_stack_tos - 1];

		reloc_stack_tos -= 1;

		break;

	default:

		printk(KERN_WARNING "module %s: unhandled reloction\n",

				mod->name);

		return 0;

	}



	/* now push the new value back on stack */

	reloc_stack_push(value);



	return value;

}



void *module_alloc(unsigned long size)

{

	if (size == 0)
@@ -334,11 +229,7 @@ apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab, 
		   undefined symbols have been resolved. */

		sym = (Elf32_Sym *) sechdrs[symindex].sh_addr

		    + ELF32_R_SYM(rel[i].r_info);

		if (is_reloc_stack_empty()) {

		value = sym->st_value;

		} else {

			value = reloc_stack_pop();

		}

		value += rel[i].r_addend;

		pr_debug("location is %x, value is %x type is %d \n",

			 (unsigned int) location32, value,
@@ -361,6 +252,12 @@ apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab, 
			location32 = (uint32_t *) location16;

			value -= (uint32_t) location32;

			value >>= 1;

			if ((value & 0xFF000000) != 0 &&

			    (value & 0xFF000000) != 0xFF000000) {

				printk(KERN_ERR "module %s: relocation overflow\n",

				       mod->name);

				return -ENOEXEC;

			}

			pr_debug("value is %x, before %x-%x after %x-%x\n", value,

			       *location16, *(location16 + 1),

			       (*location16 & 0xff00) | (value >> 16 & 0x00ff),
@@ -405,28 +302,6 @@ apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab, 
			pr_debug("before %x after %x\n", *location32, value);

			*location32 = value;

			break;

		case R_push:

			reloc_stack_push(value);

			break;

		case R_const:

			reloc_stack_push(rel[i].r_addend);

			break;

		case R_add:

		case R_sub:

		case R_mult:

		case R_div:

		case R_mod:

		case R_lshift:

		case R_rshift:

		case R_and:

		case R_or:

		case R_xor:

		case R_land:

		case R_lor:

		case R_neg:

		case R_comp:

			reloc_stack_operate(ELF32_R_TYPE(rel[i].r_info), mod);

			break;

		default:

			printk(KERN_ERR "module %s: Unknown relocation: %u\n",

			       mod->name, ELF32_R_TYPE(rel[i].r_info));