From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Mon, 20 May 2019 19:55:18 +0000 (+0000)
Subject: efi_loader: correct device path check
X-Git-Url: http://git.dujemihanovic.xyz/?a=commitdiff_plain;h=20562893fab953a1409abbe3594446ebb79d81c6;p=u-boot.git

efi_loader: correct device path check

Since commit 226cddbe32f0 ("efi_loader: check device path in
InstallMultipleProtocolInterfaces") iPXE fails to access the network.

LocateDevicePath() returns EFI_SUCCESS even if a shorter path is found as a
partial match. It returns the remaining path. So to be sure that we found a
complete match we need to check that the remaining path refers to an end
node.

Provide debug output if a device path has already been installed.

Fixes: 226cddbe32f0 ("efi_loader: check device path in
       InstallMultipleProtocolInterfaces")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---

diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 971bd5ffa3..54fff85e64 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -2360,7 +2360,10 @@ efi_status_t EFIAPI efi_install_multiple_protocol_interfaces
 
 			r = EFI_CALL(efi_locate_device_path(protocol, &dp,
 							    &old_handle));
-			if (r == EFI_SUCCESS) {
+			if (r == EFI_SUCCESS &&
+			    dp->type == DEVICE_PATH_TYPE_END) {
+				EFI_PRINT("Path %pD already installed\n",
+					  protocol_interface);
 				r = EFI_ALREADY_STARTED;
 				break;
 			}