From: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date: Wed, 20 Oct 2021 11:57:38 +0000 (+0200)
Subject: efi: check input parameter
X-Git-Tag: v250-rc1~458^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=refs%2Fpull%2F21065%2Fhead;p=thirdparty%2Fsystemd.git

efi: check input parameter

clang complained about an unused variable. We cast the buffer to
struct boot_params, so let's check that it's at least this long.
---

diff --git a/src/boot/efi/linux_x86.c b/src/boot/efi/linux_x86.c
index 98b2366ad28..15052bdff65 100644
--- a/src/boot/efi/linux_x86.c
+++ b/src/boot/efi/linux_x86.c
@@ -138,6 +138,9 @@ EFI_STATUS linux_exec(
         assert(linux_buffer);
         assert(initrd_buffer || initrd_length == 0);
 
+        if (linux_length < sizeof(struct boot_params))
+                return EFI_LOAD_ERROR;
+
         image_params = (const struct boot_params *) linux_buffer;
 
         if (image_params->hdr.boot_flag != 0xAA55 ||