lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Thu, 15 Dec 2022 15:38:17 +0300
From:   Evgeniy Baskov <baskov@...ras.ru>
To:     Ard Biesheuvel <ardb@...nel.org>
Cc:     Peter Jones <pjones@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Andy Lutomirski <luto@...nel.org>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Alexey Khoroshilov <khoroshilov@...ras.ru>,
        "Limonciello, Mario" <mario.limonciello@....com>,
        joeyli <jlee@...e.com>, lvc-project@...uxtesting.org,
        x86@...nel.org, linux-efi@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-hardening@...r.kernel.org
Subject: [PATCH v4 26/26] efi/x86: don't set unsupported memory attributes

From: Peter Jones <pjones@...hat.com>

On platforms where the firmware uses DXE, but which do not implement the
EFI Memory Attribute Protocol, we implement W^X support using DXE's
set_memory_attributes() call.  This call will fail without making any
changes if an attribute is set that isn't supported on the platform.

This patch changes efi_adjust_memory_range_protection() to avoid trying
to set any attribute bits that aren't set in the memory region's
capability flags.

Signed-off-by: Peter Jones <pjones@...hat.com>
---
 drivers/firmware/efi/libstub/mem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index 50a0b649b75a..b86ea2920d5e 100644
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -195,6 +195,7 @@ static efi_status_t adjust_mem_attrib_dxe(efi_physical_addr_t rounded_start,
 
 		desc.attributes &= ~(EFI_MEMORY_RO | EFI_MEMORY_XP);
 		desc.attributes |= attributes;
+		desc.attributes &= desc.capabilities;
 
 		unprotect_start = max(rounded_start, desc.base_address);
 		unprotect_size = min(rounded_end, next) - unprotect_start;
-- 
2.37.4

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ