diff options
Diffstat (limited to 'memattrs.c')
| -rw-r--r-- | memattrs.c | 72 |
1 files changed, 72 insertions, 0 deletions
@@ -164,4 +164,76 @@ update_mem_attrs(uintptr_t addr, uint64_t size, return ret; } +void +get_hsi_mem_info(void) +{ + EFI_STATUS efi_status; + uintptr_t addr; + uint64_t attrs = 0; + uint32_t *tmp_alloc; + + addr = ((uintptr_t)&get_hsi_mem_info) & ~EFI_PAGE_MASK; + + efi_status = get_mem_attrs(addr, EFI_PAGE_SIZE, &attrs); + if (EFI_ERROR(efi_status)) { +error: + /* + * In this case we can't actually tell anything, so assume + * and report the worst case scenario. + */ + hsi_status = SHIM_HSI_STATUS_HEAPX | + SHIM_HSI_STATUS_STACKX | + SHIM_HSI_STATUS_ROW; + dprint(L"Setting HSI to 0x%lx due to error: %r\n", hsi_status, efi_status); + return; + } else { + hsi_status = SHIM_HSI_STATUS_HASMAP; + dprint(L"Setting HSI to 0x%lx\n", hsi_status); + } + + if (!(hsi_status & SHIM_HSI_STATUS_HASMAP)) { + dprint(L"No memory protocol, not testing further\n"); + return; + } + + hsi_status = SHIM_HSI_STATUS_HASMAP; + if (attrs & MEM_ATTR_W) { + dprint(L"get_hsi_mem_info() is on a writable page: 0x%x->0x%x\n", + hsi_status, hsi_status | SHIM_HSI_STATUS_ROW); + hsi_status |= SHIM_HSI_STATUS_ROW; + } + + addr = ((uintptr_t)&addr) & ~EFI_PAGE_MASK; + efi_status = get_mem_attrs(addr, EFI_PAGE_SIZE, &attrs); + if (EFI_ERROR(efi_status)) { + dprint(L"get_mem_attrs(0x%016llx, 0x%x, &attrs) failed.\n", addr, EFI_PAGE_SIZE); + goto error; + } + + if (attrs & MEM_ATTR_X) { + dprint(L"Stack variable is on an executable page: 0x%x->0x%x\n", + hsi_status, hsi_status | SHIM_HSI_STATUS_STACKX); + hsi_status |= SHIM_HSI_STATUS_STACKX; + } + + tmp_alloc = AllocatePool(EFI_PAGE_SIZE); + if (!tmp_alloc) { + dprint(L"Failed to allocate heap variable.\n"); + goto error; + } + + addr = ((uintptr_t)tmp_alloc) & ~EFI_PAGE_MASK; + efi_status = get_mem_attrs(addr, EFI_PAGE_SIZE, &attrs); + FreePool(tmp_alloc); + if (EFI_ERROR(efi_status)) { + dprint(L"get_mem_attrs(0x%016llx, 0x%x, &attrs) failed.\n", addr, EFI_PAGE_SIZE); + goto error; + } + if (attrs & MEM_ATTR_X) { + dprint(L"Heap variable is on an executable page: 0x%x->0x%x\n", + hsi_status, hsi_status | SHIM_HSI_STATUS_HEAPX); + hsi_status |= SHIM_HSI_STATUS_HEAPX; + } +} + // vim:fenc=utf-8:tw=75:noet |