efi_selftest: check system table pointer

Enhance the debug support unit test.

Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

diff --git a/lib/efi_selftest/efi_selftest_debug_support.c b/lib/efi_selftest/efi_selftest_debug_support.c
index 9ca8b3f82f53f1ce3665b199f4f74a4af0825782..ac77caaf5610026b3085cbd21068d1c13053f653 100644 (file)
--- a/lib/efi_selftest/efi_selftest_debug_support.c
+++ b/lib/efi_selftest/efi_selftest_debug_support.c
@@ -9,6 +9,7 @@
 
 #include <efi_loader.h>
 #include <efi_selftest.h>
+#include <linux/sizes.h>
 
 /**
  * efi_st_debug_support_execute() - execute test
@@ -21,6 +22,12 @@ static int efi_st_debug_support_execute(void)
 {
        struct efi_debug_image_info_table_header *efi_st_debug_info_table_header = NULL;
        efi_guid_t efi_debug_image_info_table_guid = EFI_DEBUG_IMAGE_INFO_TABLE_GUID;
+       struct efi_mem_desc *memory_map;
+       efi_uintn_t map_size = 0;
+       efi_uintn_t map_key;
+       efi_uintn_t desc_size;
+       u32 desc_version;
+       efi_status_t ret;
 
        /* get EFI_DEBUG_IMAGE_INFO_TABLE */
        efi_st_debug_info_table_header = efi_st_get_config_table(&efi_debug_image_info_table_guid);
@@ -30,7 +37,66 @@ static int efi_st_debug_support_execute(void)
                return EFI_ST_FAILURE;
        }
 
-       return EFI_ST_SUCCESS;
+       /* Load memory map */
+       ret = st_boottime->get_memory_map(&map_size, NULL, &map_key, &desc_size,
+                                         &desc_version);
+       if (ret != EFI_BUFFER_TOO_SMALL) {
+               efi_st_error
+                       ("GetMemoryMap did not return EFI_BUFFER_TOO_SMALL\n");
+               return EFI_ST_FAILURE;
+       }
+       /* Allocate extra space for newly allocated memory */
+       map_size += sizeof(struct efi_mem_desc);
+       ret = st_boottime->allocate_pool(EFI_BOOT_SERVICES_DATA, map_size,
+                                        (void **)&memory_map);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("AllocatePool failed\n");
+               return EFI_ST_FAILURE;
+       }
+       ret = st_boottime->get_memory_map(&map_size, memory_map, &map_key,
+                                         &desc_size, &desc_version);
+       if (ret != EFI_SUCCESS) {
+               efi_st_error("GetMemoryMap failed\n");
+               return EFI_ST_FAILURE;
+       }
+       /* Find the system table pointer */
+       for (efi_uintn_t i = 0; map_size; ++i, map_size -= desc_size) {
+               struct efi_mem_desc *entry = &memory_map[i];
+               u64 end;
+
+               if (entry->type != EFI_RUNTIME_SERVICES_DATA)
+                       continue;
+
+               end = entry->physical_start +
+                     (entry->num_pages << EFI_PAGE_SHIFT);
+               for (u64 pos = ALIGN(entry->physical_start, SZ_4M);
+                    pos <= end; pos += SZ_4M) {
+                       struct efi_system_table_pointer *systab_pointer =
+                               (void *)(uintptr_t)pos;
+
+                       /* check for overflow */
+                       if (pos < entry->physical_start)
+                               break;
+                       if (systab_pointer->signature ==
+                           EFI_SYSTEM_TABLE_SIGNATURE) {
+                               if (systab_pointer->efi_system_table_base !=
+                                   (uintptr_t)st_systable) {
+                                       efi_st_error("Wrong system table address\n");
+                                       ret = EFI_ST_FAILURE;
+                                       goto out;
+                               }
+                               ret = EFI_ST_SUCCESS;
+                               goto out;
+                       }
+               }
+       }
+       efi_st_error("System table pointer not found\n");
+       ret = EFI_ST_FAILURE;
+
+out:
+       st_boottime->free_pool(memory_map);
+
+       return ret;
 }
 
 EFI_UNIT_TEST(debug_support) = {