linux-cve-announce - CVE-2023-53216: arm64: efi: Make efi_rt_lock a raw

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>] [day] [month] [year] [list]
Message-ID: <2025091512-CVE-2023-53216-7693@gregkh>
Date: Mon, 15 Sep 2025 16:21:50 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2023-53216: arm64: efi: Make efi_rt_lock a raw_spinlock

From: Greg Kroah-Hartman <gregkh@...nel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

arm64: efi: Make efi_rt_lock a raw_spinlock

Running a rt-kernel base on 6.2.0-rc3-rt1 on an Ampere Altra outputs
the following:
  BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9, name: kworker/u320:0
  preempt_count: 2, expected: 0
  RCU nest depth: 0, expected: 0
  3 locks held by kworker/u320:0/9:
  #0: ffff3fff8c27d128 ((wq_completion)efi_rts_wq){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41)
  #1: ffff80000861bdd0 ((work_completion)(&efi_rts_work.work)){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41)
  #2: ffffdf7e1ed3e460 (efi_rt_lock){+.+.}-{3:3}, at: efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101)
  Preemption disabled at:
  efi_virtmap_load (./arch/arm64/include/asm/mmu_context.h:248)
  CPU: 0 PID: 9 Comm: kworker/u320:0 Tainted: G        W          6.2.0-rc3-rt1
  Hardware name: WIWYNN Mt.Jade Server System B81.03001.0005/Mt.Jade Motherboard, BIOS 1.08.20220218 (SCP: 1.08.20220218) 2022/02/18
  Workqueue: efi_rts_wq efi_call_rts
  Call trace:
  dump_backtrace (arch/arm64/kernel/stacktrace.c:158)
  show_stack (arch/arm64/kernel/stacktrace.c:165)
  dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
  dump_stack (lib/dump_stack.c:114)
  __might_resched (kernel/sched/core.c:10134)
  rt_spin_lock (kernel/locking/rtmutex.c:1769 (discriminator 4))
  efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101)
  [...]

This seems to come from commit ff7a167961d1 ("arm64: efi: Execute
runtime services from a dedicated stack") which adds a spinlock. This
spinlock is taken through:
efi_call_rts()
\-efi_call_virt()
  \-efi_call_virt_pointer()
    \-arch_efi_call_virt_setup()

Make 'efi_rt_lock' a raw_spinlock to avoid being preempted.

[ardb: The EFI runtime services are called with a different set of
       translation tables, and are permitted to use the SIMD registers.
       The context switch code preserves/restores neither, and so EFI
       calls must be made with preemption disabled, rather than only
       disabling migration.]

The Linux kernel CVE team has assigned CVE-2023-53216 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 5.10.165 with commit 4012603cbd469223f225637d265a233f034c567a and fixed in 5.10.175 with commit 030b1c4217a4f504c7d0795a2bd86b7181e56f11
	Issue introduced in 5.15.90 with commit de2af657cab92afc13a4ccd8780370481ed0eb61 and fixed in 5.15.103 with commit 6a72729ed6accc86dad5522895e8fa2f96642a2c
	Issue introduced in 6.1.8 with commit f75a91c82dc805af8f718ff106ec9c090234b37b and fixed in 6.1.18 with commit 8b38969fa01662ec539a0d08a8ea5ec6f31fa4ed
	Issue introduced in 6.2 with commit ff7a167961d1b97e0e205f245f806e564d3505e7 and fixed in 6.2.5 with commit 4e8f7d998b582a99aadedd07ae6086e99b89c97a
	Issue introduced in 6.2 with commit ff7a167961d1b97e0e205f245f806e564d3505e7 and fixed in 6.3 with commit 0e68b5517d3767562889f1d83fdb828c26adb24f

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2023-53216
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	arch/arm64/include/asm/efi.h
	arch/arm64/kernel/efi.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/030b1c4217a4f504c7d0795a2bd86b7181e56f11
	https://git.kernel.org/stable/c/6a72729ed6accc86dad5522895e8fa2f96642a2c
	https://git.kernel.org/stable/c/8b38969fa01662ec539a0d08a8ea5ec6f31fa4ed
	https://git.kernel.org/stable/c/4e8f7d998b582a99aadedd07ae6086e99b89c97a
	https://git.kernel.org/stable/c/0e68b5517d3767562889f1d83fdb828c26adb24f