efi_loader: segfault in efi_clear_os_indications()
If we call efi_clear_os_indications() before initializing the memory store
for UEFI variables a NULL pointer dereference occurs.
The error was observed on the sandbox with:
usb start
host bind 0 sandbox.img
load host 0:1 $kernel_addr_r helloworld.efi
bootefi $kernel_addr_r
Here efi_resister_disk() failed due to an error in the BTRFS implementation.
Move the logic to clear EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED
to the rest of the capsule code.
If CONFIG_EFI_IGNORE_OSINDICATIONS=y, we should still clear the flag.
If OsIndications does not exist, we should not create it as it is owned by
the operating system.
Fixes: 149108a3eb59 ("efi_loader: clear OsIndications")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c
index 502bcfc..8301eed 100644
--- a/lib/efi_loader/efi_capsule.c
+++ b/lib/efi_loader/efi_capsule.c
@@ -1037,30 +1037,45 @@
}
/**
- * check_run_capsules - Check whether capsule update should run
+ * check_run_capsules() - check whether capsule update should run
*
* The spec says OsIndications must be set in order to run the capsule update
* on-disk. Since U-Boot doesn't support runtime SetVariable, allow capsules to
* run explicitly if CONFIG_EFI_IGNORE_OSINDICATIONS is selected
+ *
+ * Return: EFI_SUCCESS if update to run, EFI_NOT_FOUND otherwise
*/
-static bool check_run_capsules(void)
+static efi_status_t check_run_capsules(void)
{
u64 os_indications;
efi_uintn_t size;
- efi_status_t ret;
-
- if (IS_ENABLED(CONFIG_EFI_IGNORE_OSINDICATIONS))
- return true;
+ efi_status_t r;
size = sizeof(os_indications);
- ret = efi_get_variable_int(L"OsIndications", &efi_global_variable_guid,
- NULL, &size, &os_indications, NULL);
- if (ret == EFI_SUCCESS &&
- (os_indications
- & EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED))
- return true;
+ r = efi_get_variable_int(L"OsIndications", &efi_global_variable_guid,
+ NULL, &size, &os_indications, NULL);
+ if (r != EFI_SUCCESS || size != sizeof(os_indications))
+ return EFI_NOT_FOUND;
- return false;
+ if (os_indications &
+ EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED) {
+ os_indications &=
+ ~EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED;
+ r = efi_set_variable_int(L"OsIndications",
+ &efi_global_variable_guid,
+ EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS,
+ sizeof(os_indications),
+ &os_indications, false);
+ if (r != EFI_SUCCESS)
+ log_err("Setting %ls failed\n", L"OsIndications");
+ return EFI_SUCCESS;
+ } else if (IS_ENABLED(CONFIG_EFI_IGNORE_OSINDICATIONS)) {
+ return EFI_SUCCESS;
+ } else {
+ return EFI_NOT_FOUND;
+ }
}
/**
@@ -1078,7 +1093,7 @@
unsigned int nfiles, index, i;
efi_status_t ret;
- if (!check_run_capsules())
+ if (check_run_capsules() != EFI_SUCCESS)
return EFI_SUCCESS;
index = get_last_capsule();
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index a2338d7..1aba71c 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -176,43 +176,13 @@
/**
- * efi_clear_os_indications() - clear OsIndications
- *
- * Clear EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED
- */
-static efi_status_t efi_clear_os_indications(void)
-{
- efi_uintn_t size;
- u64 os_indications;
- efi_status_t ret;
-
- size = sizeof(os_indications);
- ret = efi_get_variable_int(L"OsIndications", &efi_global_variable_guid,
- NULL, &size, &os_indications, NULL);
- if (ret != EFI_SUCCESS)
- os_indications = 0;
- else
- os_indications &=
- ~EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED;
- ret = efi_set_variable_int(L"OsIndications", &efi_global_variable_guid,
- EFI_VARIABLE_NON_VOLATILE |
- EFI_VARIABLE_BOOTSERVICE_ACCESS |
- EFI_VARIABLE_RUNTIME_ACCESS,
- sizeof(os_indications), &os_indications,
- false);
- if (ret != EFI_SUCCESS)
- log_err("Setting %ls failed\n", L"OsIndications");
- return ret;
-}
-
-/**
* efi_init_obj_list() - Initialize and populate EFI object list
*
* Return: status code
*/
efi_status_t efi_init_obj_list(void)
{
- efi_status_t r, ret = EFI_SUCCESS;
+ efi_status_t ret = EFI_SUCCESS;
/* Initialize once only */
if (efi_obj_list_initialized != OBJ_LIST_NOT_INITIALIZED)
@@ -331,11 +301,7 @@
if (IS_ENABLED(CONFIG_EFI_CAPSULE_ON_DISK) &&
!IS_ENABLED(CONFIG_EFI_CAPSULE_ON_DISK_EARLY))
ret = efi_launch_capsules();
-
out:
- r = efi_clear_os_indications();
- if (ret == EFI_SUCCESS)
- ret = r;
efi_obj_list_initialized = ret;
return ret;
}