linux-kernel - [PATCH v1 12/15] powerpc/kuap: Wire-up KUAP on 40x

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]

Message-Id: <21fba0d5addd3ec1f90d742c21b86dabc208fc32.1633523837.git.christophe.leroy@csgroup.eu>
Date:   Wed,  6 Oct 2021 14:43:45 +0200
From:   Christophe Leroy <christophe.leroy@...roup.eu>
To:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>
Cc:     Christophe Leroy <christophe.leroy@...roup.eu>,
        linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH v1 12/15] powerpc/kuap: Wire-up KUAP on 40x

This adds KUAP support to 40x. This is done by checking
the content of SPRN_PID at the time user pgtable is loaded.

Signed-off-by: Christophe Leroy <christophe.leroy@...roup.eu>
---
 arch/powerpc/kernel/head_40x.S         | 8 ++++++++
 arch/powerpc/platforms/Kconfig.cputype | 1 +
 2 files changed, 9 insertions(+)

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 7d72ee5ab387..87d322dbed94 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -297,6 +297,10 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 3:
 	mfspr	r11,SPRN_SPRG_THREAD
 	lwz	r11,PGDIR(r11)
+#ifdef CONFIG_PPC_KUAP
+	rlwinm.	r9, r9, 0, 0xff
+	beq	5f			/* Kuap fault */
+#endif
 4:
 	tophys(r11, r11)
 	rlwimi	r11, r10, 12, 20, 29	/* Create L1 (pgdir/pmd) address */
@@ -377,6 +381,10 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 3:
 	mfspr	r11,SPRN_SPRG_THREAD
 	lwz	r11,PGDIR(r11)
+#ifdef CONFIG_PPC_KUAP
+	rlwinm.	r9, r9, 0, 0xff
+	beq	5f			/* Kuap fault */
+#endif
 4:
 	tophys(r11, r11)
 	rlwimi	r11, r10, 12, 20, 29	/* Create L1 (pgdir/pmd) address */
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 74e5887abbce..3fdc10bc4aab 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -53,6 +53,7 @@ config 40x
 	select PPC_UDBG_16550
 	select 4xx_SOC
 	select HAVE_PCI
+	select PPC_HAVE_KUAP
 
 config 44x
 	bool "AMCC 44x, 46x or 47x"
-- 
2.31.1