This is a note to let you know that I've just added the patch titled
powerpc/32s: Add missing call to kuep_lock on syscall entry
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-32s-add-missing-call-to-kuep_lock-on-syscall-entry.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 57fdfbce89137ae85cd5cef48be168040a47dd13 Mon Sep 17 00:00:00 2001
From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Date: Mon, 8 Feb 2021 15:10:20 +0000
Subject: powerpc/32s: Add missing call to kuep_lock on syscall entry
From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
commit 57fdfbce89137ae85cd5cef48be168040a47dd13 upstream.
Userspace Execution protection and fast syscall entry were implemented
independently from each other and were both merged in kernel 5.2,
leading to syscall entry missing userspace execution protection.
On syscall entry, execution of user space memory must be
locked in the same way as on exception entry.
Fixes: b86fb88855ea ("powerpc/32: implement fast entry for syscalls on non BOOKE")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/c65e105b63aaf74f91a14f845bc77192350b84a6.1612796617.git.christophe.leroy@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kernel/entry_32.S | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -336,6 +336,9 @@ trace_syscall_entry_irq_off:
.globl transfer_to_syscall
transfer_to_syscall:
+#ifdef CONFIG_PPC_BOOK3S_32
+ kuep_lock r11, r12
+#endif
#ifdef CONFIG_TRACE_IRQFLAGS
andi. r12,r9,MSR_EE
beq- trace_syscall_entry_irq_off
Patches currently in stable-queue which might be from christophe.leroy@xxxxxxxxxx are
queue-5.4/powerpc-8xx-fix-software-emulation-interrupt.patch
queue-5.4/powerpc-32s-add-missing-call-to-kuep_lock-on-syscall-entry.patch
queue-5.4/crypto-talitos-work-around-sec6-errata-aes-ctr-mode-.patch
queue-5.4/powerpc-47x-disable-256k-page-size.patch
