efi_loader: fix AppendDevicePath
The logic of the AppendDevicePath service of the
EFI_DEVICE_PATH_UTILITIES_PROTOCOL is incorrectly implemented:
* if both paths are NULL an end node has to be returned
* if both paths are not NULL the end node of the second device path has to
be kept
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c
index 0cd0b45..9b4d9ae 100644
--- a/lib/efi_loader/efi_device_path.c
+++ b/lib/efi_loader/efi_device_path.c
@@ -263,7 +263,10 @@
{
struct efi_device_path *ret;
- if (!dp1) {
+ if (!dp1 && !dp2) {
+ /* return an end node */
+ ret = efi_dp_dup(&END);
+ } else if (!dp1) {
ret = efi_dp_dup(dp2);
} else if (!dp2) {
ret = efi_dp_dup(dp1);
@@ -275,8 +278,8 @@
if (!p)
return NULL;
memcpy(p, dp1, sz1);
- memcpy(p + sz1, dp2, sz2);
- memcpy(p + sz1 + sz2, &END, sizeof(END));
+ /* the end node of the second device path has to be retained */
+ memcpy(p + sz1, dp2, sz2 + sizeof(END));
ret = p;
}