Fix update sector flag index truncation

F/2586

Author: danielinux

src/libwolfboot.c

@@ -693,7 +693,7 @@ int RAMFUNCTION wolfBoot_set_update_sector_flag(uint16_t sector,
     uint32_t *magic;
     uint8_t *flags;
     uint8_t fl_value;
-    uint8_t pos = sector >> 1;
+    uint32_t pos = sector >> 1;
 
     magic = get_partition_magic(PART_UPDATE);
     if (*magic != wolfboot_magic_trail)
@@ -748,7 +748,7 @@ int wolfBoot_get_update_sector_flag(uint16_t sector, uint8_t *flag)
 {
     uint32_t *magic;
     uint8_t *flags;
-    uint8_t pos = sector >> 1;
+    uint32_t pos = sector >> 1;
     magic = get_partition_magic(PART_UPDATE);
     if (*magic != WOLFBOOT_MAGIC_TRAIL)
         return -1;

tools/unit-tests/unit-nvm.c

@@ -362,6 +362,43 @@ START_TEST(test_get_update_sector_flag_rejects_invalid_magic)
 }
 END_TEST
 
+START_TEST(test_update_sector_flag_high_index_does_not_alias_low_index)
+{
+    int ret;
+    uint8_t st = 0;
+
+    ret = mmap_file("/tmp/wolfboot-unit-high-index.bin", (void *)MOCK_ADDRESS,
+            WOLFBOOT_PARTITION_SIZE, NULL);
+    ck_assert(ret >= 0);
+#ifdef FLAGS_HOME
+    ret = mmap_file("/tmp/wolfboot-unit-high-index-int.bin",
+            (void *)MOCK_ADDRESS_BOOT, WOLFBOOT_PARTITION_SIZE, NULL);
+    ck_assert(ret >= 0);
+#endif
+    ret = mmap_file("/tmp/wolfboot-unit-high-index-swap.bin",
+            (void *)MOCK_ADDRESS_SWAP, WOLFBOOT_SECTOR_SIZE, NULL);
+    ck_assert(ret >= 0);
+
+    hal_flash_unlock();
+    wolfBoot_erase_partition(PART_UPDATE);
+
+    ret = wolfBoot_set_update_sector_flag(1, SECT_FLAG_SWAPPING);
+    ck_assert_int_eq(ret, 0);
+    ret = wolfBoot_set_update_sector_flag(512, SECT_FLAG_UPDATED);
+    ck_assert_int_eq(ret, 0);
+
+    ret = wolfBoot_get_update_sector_flag(1, &st);
+    ck_assert_int_eq(ret, 0);
+    ck_assert_uint_eq(st, SECT_FLAG_SWAPPING);
+
+    ret = wolfBoot_get_update_sector_flag(512, &st);
+    ck_assert_int_eq(ret, 0);
+    ck_assert_uint_eq(st, SECT_FLAG_UPDATED);
+
+    hal_flash_lock();
+}
+END_TEST
+
 
 Suite *wolfboot_suite(void)
 {
@@ -375,6 +412,8 @@ Suite *wolfboot_suite(void)
             test_partition_magic_write_stops_on_flash_write_error);
     tcase_add_test(nvm_select_fresh_sector,
             test_get_update_sector_flag_rejects_invalid_magic);
+    tcase_add_test(nvm_select_fresh_sector,
+            test_update_sector_flag_high_index_does_not_alias_low_index);
     suite_add_tcase(s, nvm_select_fresh_sector);
 
     return s;