src/arch/x86/stack_canary_breakpoint.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <arch/breakpoint.h>
   4 #include <arch/stack_canary_breakpoint.h>
   5 #include <arch/symbols.h>
   6 #include <bootstate.h>
   7 #include <console/console.h>
   8 #include <types.h>
   9 #include <symbols.h>
  10
  11 static struct breakpoint_handle stack_canary_bp;
  12
  13 static int handle_stack_canary_written(struct breakpoint_handle handle, struct eregs *regs)
  14 {
  15 #if ENV_X86_64
  16         printk(BIOS_ERR, "Stack corruption detected at rip: 0x%llx\n", regs->rip);
  17 #else
  18         printk(BIOS_ERR, "Stack corruption detected at eip: 0x%x\n", regs->eip);
  19 #endif
  20         return 0;
  21 }
  22
  23 static void create_stack_canary_breakpoint(uintptr_t *addr)
  24 {
  25         enum breakpoint_result res =
  26                 breakpoint_create_data(&stack_canary_bp, addr, sizeof(uintptr_t), true);
  27
  28         if (res != BREAKPOINT_RES_OK) {
  29                 printk(BIOS_ERR, "Failed to create stack canary breakpoint\n");
  30                 return;
  31         }
  32
  33         breakpoint_set_handler(stack_canary_bp, &handle_stack_canary_written);
  34         breakpoint_enable(stack_canary_bp, true);
  35 }
  36
  37 void stack_canary_breakpoint_init(void)
  38 {
  39         uintptr_t *addr;
  40
  41         if (CONFIG(RESET_VECTOR_IN_RAM)) {
  42                 addr = (uintptr_t *)_earlyram_stack;
  43         } else if (ENV_CACHE_AS_RAM) {
  44                 addr = (uintptr_t *)_car_stack;
  45         } else {
  46                 addr = (uintptr_t *)_stack;
  47         }
  48
  49         create_stack_canary_breakpoint(addr);
  50 }
  51
  52 void stack_canary_breakpoint_remove(void)
  53 {
  54         breakpoint_remove(stack_canary_bp);
  55 }
  56
  57 static void stack_canary_breakpoint_remove_hook(void *unused)
  58 {
  59         stack_canary_breakpoint_remove();
  60 }
  61
  62 BOOT_STATE_INIT_ENTRY(BS_OS_RESUME, BS_ON_ENTRY, stack_canary_breakpoint_remove_hook, NULL);
  63 BOOT_STATE_INIT_ENTRY(BS_PAYLOAD_BOOT, BS_ON_ENTRY, stack_canary_breakpoint_remove_hook, NULL);