efi_loader: check device path is not installed twice

Prior to corrective patches for virtio and SATA devices the same device
path was installed on two different handles. This is not allowable.
With this patch we will throw an error if this condition occurs for
block devices.

Update a comment for the installation of the simple file system
protocol.

Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Heinrich Schuchardt 2020-05-21 09:22:06 +02:00
parent bf3bcef7fb
commit 0a87e05dbd

View file

@ -356,6 +356,7 @@ static efi_status_t efi_disk_add_dev(
struct efi_disk_obj **disk)
{
struct efi_disk_obj *diskobj;
struct efi_object *handle;
efi_status_t ret;
/* Don't add empty devices */
@ -379,15 +380,25 @@ static efi_status_t efi_disk_add_dev(
diskobj->dp = efi_dp_from_part(desc, part);
}
diskobj->part = part;
ret = efi_add_protocol(&diskobj->header, &efi_block_io_guid,
&diskobj->ops);
/*
* Install the device path and the block IO protocol.
*
* InstallMultipleProtocolInterfaces() checks if the device path is
* already installed on an other handle and returns EFI_ALREADY_STARTED
* in this case.
*/
handle = &diskobj->header;
ret = EFI_CALL(efi_install_multiple_protocol_interfaces(
&handle, &efi_guid_device_path, diskobj->dp,
&efi_block_io_guid, &diskobj->ops, NULL));
if (ret != EFI_SUCCESS)
return ret;
ret = efi_add_protocol(&diskobj->header, &efi_guid_device_path,
diskobj->dp);
if (ret != EFI_SUCCESS)
return ret;
/* partitions or whole disk without partitions */
/*
* On partitions or whole disks without partitions install the
* simple file system protocol if a file system is available.
*/
if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
efi_fs_exists(desc, part)) {
diskobj->volume = efi_simple_file_system(desc, part,