On 10/6/22 03:53, AKASHI Takahiro wrote:
On Wed, Oct 05, 2022 at 06:26:02PM +0300, Ilias Apalodimas wrote:
In general handles should only be deleted if the last remaining protocol is removed. Instead of explicitly calling efi_create_handle -> efi_add_protocol -> efi_delete_handle which blindly removes all protocols from a handle before removing it, use InstallMultiple/UninstallMultiple which adheres to the EFI spec and only deletes a handle if there are no additional protocols present
Signed-off-by: Ilias Apalodimas ilias.apalodimas@linaro.org
cmd/bootefi.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/cmd/bootefi.c b/cmd/bootefi.c index 3041873afbbc..4ab68868cc7e 100644 --- a/cmd/bootefi.c +++ b/cmd/bootefi.c @@ -509,12 +509,9 @@ efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size) * Make sure that device for device_path exist * in load_image(). Otherwise, shell and grub will fail. */
ret = efi_create_handle(&mem_handle);if (ret != EFI_SUCCESS)goto out;ret = efi_add_protocol(mem_handle, &efi_guid_device_path,file_path);
ret = efi_install_multiple_protocol_interfaces(&mem_handle,&efi_guid_device_path,file_path, NULL);nitpick: NULL -> NULL, NULL UEFI spec seems to require "A variable argument list containing pairs of protocol GUIDs and protocol interfaces" even if a protocol interface won't be used with GUID as NULL.
The spec also has: "The pairs of arguments are removed in order from the variable argument list until a NULL protocol GUID value is found."
This is what a calls inside EDK II looks like:
Status = CoreInstallMultipleProtocolInterfaces ( &mDecompressHandle, &gEfiDecompressProtocolGuid, &gEfiDecompress, NULL );
gBS->UninstallMultipleProtocolInterfaces ( Controller, &gEfiCallerIdGuid, AtaBusDriverData, NULL );
So I am happy with a single NULL here.
-Takahiro Akashi
if (ret != EFI_SUCCESS) goto out; msg_path = file_path;@@ -542,7 +539,9 @@ efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size) ret = do_bootefi_exec(handle, load_options);
out:
- efi_delete_handle(mem_handle);
- efi_uninstall_multiple_protocol_interfaces(mem_handle,
&efi_guid_device_path,file_path, NULL);
We have installed a lot more protocols. The binary may have installed additional protocols. Consider the case of a boottime driver. To delete the handle we would have to remove all installed protocols.
UninstallMultipleProtocolInterfaces() may fail if one of the protocols was opened with ByDriver or ByChildcontroller. The return value has to be considered before freeing file_path.
Best regards
Heinrich
efi_free_pool(file_path); return ret; } -- 2.34.1