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();