UEFI Shell sticks the UCS2 of li->FilePath in li->LoadOptions. Ignore it.

If li->LoadOptions tells us to execute our own binary, it's clearly not
what we want to do for the second stage.  So simply ignore that case.

Signed-off-by: Peter Jones <pjones@redhat.com>

2 files changed, 63 insertions, 1 deletions

diff --git a/shim.c b/shim.c
index dcf1c516..32b3ae95 100644
--- a/shim.c
+++ b/shim.c
@@ -41,6 +41,7 @@
 #include "signature.h"
 #include "netboot.h"
 #include "shim_cert.h"
+#include "ucs2.h"
 
 #define DEFAULT_LOADER L"\\grub.efi"
 #define MOK_MANAGER L"\\MokManager.efi"
@@ -1328,6 +1329,7 @@ EFI_STATUS set_second_stage (EFI_HANDLE image_handle)
 {
 	EFI_STATUS status;
 	EFI_LOADED_IMAGE *li;
+	CHAR16 *bootpath = NULL;
 	CHAR16 *start = NULL, *c;
 	int i, remaining_size = 0;
 
@@ -1361,7 +1363,10 @@ EFI_STATUS set_second_stage (EFI_HANDLE image_handle)
 		}
 	}
 
-	second_stage = (CHAR16 *)li->LoadOptions;
+	bootpath = DevicePathToStr(li->FilePath);
+	if (!StrCaseCmp(bootpath, (CHAR16 *)li->LoadOptions))
+		second_stage = (CHAR16 *)li->LoadOptions;
+
 	if (start && remaining_size > 0) {
 		load_options = start;
 		load_options_size = remaining_size;
diff --git a/ucs2.h b/ucs2.h
new file mode 100644
index 00000000..7c49b09b
--- /dev/null
+++ b/ucs2.h
@@ -0,0 +1,57 @@
+/*
+ * shim - trivial UEFI first-stage bootloader
+ *
+ * Copyright 2013 Red Hat, Inc <pjones@redhat.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Significant portions of this code are derived from Tianocore
+ * (http://tianocore.sf.net) and are Copyright 2009-2012 Intel
+ * Corporation.
+ */
+
+#ifndef SHIM_UCS2_H
+#define SHIM_UCS2_H
+
+static inline INTN
+__attribute__((unused))
+StrCaseCmp(CHAR16 *s0, CHAR16 *s1)
+{
+	CHAR16 c0, c1;
+	while (1) {
+		if (*s0 == L'\0' || *s1 == L'\0')
+			return *s1 - *s0;
+		c0 = (*s0 >= L'a' && *s0 <= L'z') ? *s0 - 32 : *s0;
+		c1 = (*s1 >= L'a' && *s1 <= L'z') ? *s1 - 32 : *s1;
+		if (c0 != c1)
+			return c1 - c0;
+		s0++;
+		s1++;
+	}
+	return 0;
+}
+
+#endif /* SHIM_UCS2_H */