The caller of disk_get_part_uuid is responsible for checking the return
value, as this function returns NULL in case of an error. This was not
done, leading to a nullptr dereference on error.
We fix this by checking the return code. Further, we now issue a error
message in case the UUID cannot be determined.
Fixes: 7c90e82 ("efi: implement systemd boot loader interface")
Reported-by: Jan Kiszka <[email protected]>
Signed-off-by: Felix Moessbauer <[email protected]>
---
main.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/main.c b/main.c
index f0b9aa0..e19b1f9 100644
--- a/main.c
+++ b/main.c
@@ -189,14 +189,18 @@ EFI_STATUS efi_main(EFI_HANDLE image_handle,
EFI_SYSTEM_TABLE *system_table)
UINT16 *boot_medium_uuidstr =
disk_get_part_uuid(loaded_image->DeviceHandle);
- bg_interface_params.loader_device_part_uuid = boot_medium_uuidstr;
- status = set_bg_interface_vars(&bg_interface_params);
- if (EFI_ERROR(status)) {
- ERROR(L"Cannot set bootloader interface variables (%r)\n",
- status);
+ if (!boot_medium_uuidstr) {
+ ERROR(L"Cannot get boot partition UUID\n");
+ } else {
+ bg_interface_params.loader_device_part_uuid =
boot_medium_uuidstr;
+ status = set_bg_interface_vars(&bg_interface_params);
+ if (EFI_ERROR(status)) {
+ ERROR(L"Cannot set bootloader interface variables
(%r)\n",
+ status);
+ }
+ INFO(L"LoaderDevicePartUUID=%s\n", boot_medium_uuidstr);
+ FreePool(boot_medium_uuidstr);
}
- INFO(L"LoaderDevicePartUUID=%s\n", boot_medium_uuidstr);
- FreePool(boot_medium_uuidstr);
FreePool(payload_dev_path);
FreePool(boot_medium_path);
--
2.49.0
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