From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Wed, 4 Sep 2019 20:46:13 +0000 (+0200)
Subject: efi_loader: do not set invalid screen mode
X-Git-Tag: v2019.10-rc4~21^2~4
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=03446987c5008fd1e3732b01fd63a29c7a6d9246;p=oweals%2Fu-boot.git

efi_loader: do not set invalid screen mode

EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.SetMode() should return EFI_UNDEFINED if a
screen mode is not available.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Alexander Graf <agraf@csgraf.de>
---

diff --git a/lib/efi_loader/efi_console.c b/lib/efi_loader/efi_console.c
index 5560fc8dea..5109017796 100644
--- a/lib/efi_loader/efi_console.c
+++ b/lib/efi_loader/efi_console.c
@@ -379,6 +379,10 @@ static efi_status_t EFIAPI efi_cout_set_mode(
 
 	if (mode_number >= efi_con_mode.max_mode)
 		return EFI_EXIT(EFI_UNSUPPORTED);
+
+	if (!efi_cout_modes[mode_number].present)
+		return EFI_EXIT(EFI_UNSUPPORTED);
+
 	efi_con_mode.mode = mode_number;
 	EFI_CALL(efi_cout_clear_screen(this));