linux-kernel - [PATCH v4 2/4] x86/signal: Use write_permissive_pkey

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-next>] [day] [month] [year] [list]

Message-ID: <85372b646f6d316e38578632cb4678f8ce724b95.1740403209.git.dvyukov@google.com>
Date: Mon, 24 Feb 2025 14:20:46 +0100
From: Dmitry Vyukov <dvyukov@...gle.com>
To: mathieu.desnoyers@...icios.com, peterz@...radead.org, boqun.feng@...il.com, 
	tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, 
	dave.hansen@...ux.intel.com, hpa@...or.com, aruna.ramakrishna@...cle.com, 
	elver@...gle.com
Cc: Dmitry Vyukov <dvyukov@...gle.com>, "Paul E. McKenney" <paulmck@...nel.org>, x86@...nel.org, 
	linux-kernel@...r.kernel.org
Subject: [PATCH v4 2/4] x86/signal: Use write_permissive_pkey_val() helper

Use the new switch_to_permissive_pkey_reg() helper instead of the
custom code. No functional changes intended.

Signed-off-by: Dmitry Vyukov <dvyukov@...gle.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: "Paul E. McKenney" <paulmck@...nel.org>
Cc: Boqun Feng <boqun.feng@...il.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: Borislav Petkov <bp@...en8.de>
Cc: Dave Hansen <dave.hansen@...ux.intel.com>
Cc: "H. Peter Anvin" <hpa@...or.com>
Cc: Aruna Ramakrishna <aruna.ramakrishna@...cle.com>
Cc: x86@...nel.org
Cc: linux-kernel@...r.kernel.org

---
Changes in v3:
 - restore sig_prepare_pkru with the large comment and
   make it call the new write_permissive_pkey_val
---
 arch/x86/kernel/signal.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 5f441039b5725..27a66a0697dd2 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -28,6 +28,7 @@
 #include <linux/entry-common.h>
 #include <linux/syscalls.h>
 #include <linux/rseq.h>
+#include <linux/pkeys.h>

 #include <asm/processor.h>
 #include <asm/ucontext.h>
@@ -72,10 +73,7 @@ static inline int is_x32_frame(struct ksignal *ksig)
  */
 static inline u32 sig_prepare_pkru(void)
 {
-	u32 orig_pkru = read_pkru();
-
-	write_pkru(0);
-	return orig_pkru;
+	return write_permissive_pkey_val();
 }

 /*
-- 
2.48.1.601.g30ceb7b040-goog