- Refactor find_handle() to improve device path comparison logic. - Original logic only compared paths when len_current <= len. - This fails when searching for ESP inside a larger boot device. - ESP partition path is longer than boot device path by design. - New logic allows matching when dp is a prefix of dp_current. - Without this change, it was not able to find ESP and capsule update fails to start.
- Also update efi_fs_from_path() to use system partition GUID. - Above ensures ESP's EFI handle is returned which contains file system protocol. - Without this change, it was returning a wrong EFI handle that was not ESP handle. - These changes improves reliability for capsule updates. Signed-off-by: Balaji Selvanathan <[email protected]> --- lib/efi_loader/efi_device_path.c | 62 ++++++++++++++++++++++---------- lib/efi_loader/efi_disk.c | 2 +- 2 files changed, 45 insertions(+), 19 deletions(-) diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c index b3fb20b2501..3716165e963 100644 --- a/lib/efi_loader/efi_device_path.c +++ b/lib/efi_loader/efi_device_path.c @@ -107,54 +107,80 @@ struct efi_device_path *efi_dp_shorten(struct efi_device_path *dp) * @rem: pointer to receive remaining device path * Return: matching handle */ + static efi_handle_t find_handle(struct efi_device_path *dp, const efi_guid_t *guid, bool short_path, struct efi_device_path **rem) { efi_handle_t handle, best_handle = NULL; - efi_uintn_t len, best_len = 0; + efi_uintn_t len, len_current, best_len = 0; + efi_status_t ret; + struct efi_device_path *dp_current; + struct efi_handler *handler; len = efi_dp_instance_size(dp); list_for_each_entry(handle, &efi_obj_list, link) { - struct efi_handler *handler; - struct efi_device_path *dp_current; - efi_uintn_t len_current; - efi_status_t ret; - if (guid) { ret = efi_search_protocol(handle, guid, &handler); if (ret != EFI_SUCCESS) continue; } - ret = efi_search_protocol(handle, &efi_guid_device_path, - &handler); + + ret = efi_search_protocol(handle, &efi_guid_device_path, &handler); if (ret != EFI_SUCCESS) continue; + dp_current = handler->protocol_interface; if (short_path) { dp_current = efi_dp_shorten(dp_current); if (!dp_current) continue; } + len_current = efi_dp_instance_size(dp_current); + if (rem) { - if (len_current > len) + /* If current path is shorter than or equal to input path */ + if (len_current <= len) { + if (memcmp(dp_current, dp, len_current)) + continue; + if (!rem) + return handle; + if (len_current > best_len) { + best_len = len_current; + best_handle = handle; + *rem = (void *)((u8 *)dp + len_current); + } + } + /* If current path is greater than input path */ + else if (len_current > len) { + if (memcmp(dp, dp_current, len)) + continue; + if (len > best_len) { + best_len = len; + best_handle = handle; + *rem = (struct efi_device_path *)((u8 *)dp_current + len); + } + } else { continue; + } } else { - if (len_current != len) + if (len_current == len) { + if (memcmp(dp_current, dp, len_current)) + continue; + } + /* If current path is greater than input path */ + else if (len_current > len) { + if (memcmp(dp, dp_current, len)) + continue; + } else { continue; - } - if (memcmp(dp_current, dp, len_current)) - continue; - if (!rem) + } return handle; - if (len_current > best_len) { - best_len = len_current; - best_handle = handle; - *rem = (void*)((u8 *)dp + len_current); } } + return best_handle; } diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c index 130c4db9606..49f8b5935f4 100644 --- a/lib/efi_loader/efi_disk.c +++ b/lib/efi_loader/efi_disk.c @@ -339,7 +339,7 @@ efi_fs_from_path(struct efi_device_path *full_path) efi_free_pool(file_path); /* Get the EFI object for the partition */ - efiobj = efi_dp_find_obj(device_path, NULL, NULL); + efiobj = efi_dp_find_obj(device_path, &efi_system_partition_guid, NULL); efi_free_pool(device_path); if (!efiobj) return NULL; -- 2.34.1
