From ada7ff69bd8a95614aa63dd618764daf428f235d Mon Sep 17 00:00:00 2001

From: Gary Lin <glin@suse.com>

Date: Fri, 4 Jun 2021 17:02:31 +0800

Subject: [PATCH 22/35] shim: don't fail on the odd LoadOptions length

Some firmware feeds the LoadOptions with an odd length when booting from

an USB device(*). We should only skip this kind of LoadOptions, not fail

it, or the user won't be able to boot the system from USB or CD-ROM.

(*) https://bugzilla.suse.com/show_bug.cgi?id=1185232#c62

Signed-off-by: Gary Lin <glin@suse.com>

---

 load-options.c | 12 ++++++++++--

 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/load-options.c b/load-options.c

index 480832c1..e34aa381 100644

--- a/load-options.c

+++ b/load-options.c

@@ -310,9 +310,17 @@ parse_load_options(EFI_LOADED_IMAGE *li)

 	UINT32 remaining_size;

 	CHAR16 *loader_str = NULL;

-	/* Sanity check since we make several assumptions about the length */

+	/*

+	 * Sanity check since we make several assumptions about the length

+	 * Some firmware feeds the following load option when booting from

+	 * an USB device:

+	 *

+	 *    0x46 0x4a 0x00 |FJ.|

+	 *

+	 * The string is meaningless for shim and so just ignore it.

+	 */

 	if (li->LoadOptionsSize % 2 != 0)

-		return EFI_INVALID_PARAMETER;

+		return EFI_SUCCESS;

 	/* So, load options are a giant pain in the ass.  If we're invoked

 	 * from the EFI shell, we get something like this:

-- 

2.32.0