[PATCH] efi: allow LoadImage from a source buffer

[Ahmad Fatoum <a.fatoum@barebox.org>]

LoadImage is allowed to load a PE image from a caller-provided source
buffer when no device path is supplied. The SCT covers that path and
barebox only handled filesystem-backed images, so valid test images were
rejected before StartImage could run them.

Add the source-buffer path and feed it through the normal image loader so
the loaded image uses the same validation and bookkeeping as file-backed
images.

Assisted-by: Codex:gpt-5.5
Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
 efi/loader/boot.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/efi/loader/boot.c b/efi/loader/boot.c
index b92e6bb33093..d34de119f4e7 100644
--- a/efi/loader/boot.c
+++ b/efi/loader/boot.c
@@ -1988,8 +1988,7 @@ efi_status_t EFIAPI efiloader_load_image(bool boot_policy,
 	EFI_ENTRY("%d, %p, %pD, %p, %zu, %p", boot_policy, parent_image,
 		  file_path, source_buffer, source_size, image_handle);
 
-	if (!image_handle || (!source_buffer && !file_path) ||
-	    !efi_search_obj(parent_image) ||
+	if (!image_handle || !efi_search_obj(parent_image) ||
 	    /* The parent image handle must refer to a loaded image */
 	    !parent_image->type) {
 		ret = EFI_INVALID_PARAMETER;
@@ -2005,8 +2004,14 @@ efi_status_t EFIAPI efiloader_load_image(bool boot_policy,
 	} else {
 		dest_buffer = source_buffer;
 	}
-	/* split file_path which contains both the device and file parts */
-	ret = efi_dp_split_file_path(file_path, &dp, &fp);
+	if (file_path) {
+		/* split file_path which contains both the device and file parts */
+		ret = efi_dp_split_file_path(file_path, &dp, &fp);
+	} else {
+		dp = NULL;
+		fp = NULL;
+		ret = EFI_SUCCESS;
+	}
 	if (ret == EFI_SUCCESS) {
 		ret = efi_setup_loaded_image(dp, fp, image_obj, &info);
 		if (ret == EFI_SUCCESS)
-- 
2.47.3