Commit 86f46f34 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32s: Initialise KUAP and KUEP in C 



In order to selectively activate KUAP and KUEP in a following patch,
perform KUAP and KUEP initialisation in C.

Unlike PPC64, PPC32 doesn't have an early_setup_secondary(),
so do it in start_secondary().

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/87be72023448dd4e476744ed279b8c04b8d08a1c.1622708530.git.christophe.leroy@csgroup.eu
parent 882136fb

arch/powerpc/kernel/head_book3s_32.S

+0 −6
Original line number Diff line number Diff line
@@ -934,12 +934,6 @@ _GLOBAL(load_segment_registers) 
	li	r0, NUM_USER_SEGMENTS /* load up user segment register values */

	mtctr	r0		/* for context 0 */

	li	r3, 0		/* Kp = 0, Ks = 0, VSID = 0 */

#ifdef CONFIG_PPC_KUEP

	oris	r3, r3, SR_NX@h	/* Set Nx */

#endif

#ifdef CONFIG_PPC_KUAP

	oris	r3, r3, SR_KS@h	/* Set Ks */

#endif

	li	r4, 0

3:	mtsrin	r3, r4

	addi	r3, r3, 0x111	/* increment VSID */

arch/powerpc/kernel/smp.c

+4 −0
Original line number Diff line number Diff line
@@ -1541,6 +1541,10 @@ void start_secondary(void *unused) 
{

	unsigned int cpu = raw_smp_processor_id();



	/* PPC64 calls setup_kup() in early_setup_secondary() */

	if (IS_ENABLED(CONFIG_PPC32))

		setup_kup();



	mmgrab(&init_mm);

	current->active_mm = &init_mm;

arch/powerpc/mm/book3s32/kuap.c

+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later



#include <asm/kup.h>

#include <asm/smp.h>



void __init setup_kuap(bool disabled)

{

	kuap_update_sr(mfsr(0) | SR_KS, 0, TASK_SIZE);



	if (smp_processor_id() != boot_cpuid)

		return;



	pr_info("Activating Kernel Userspace Access Protection\n");



	if (disabled)

arch/powerpc/mm/book3s32/kuep.c

+6 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later



#include <asm/kup.h>

#include <asm/smp.h>



void __init setup_kuep(bool disabled)

{

	kuep_lock();



	if (smp_processor_id() != boot_cpuid)

		return;



	pr_info("Activating Kernel Userspace Execution Prevention\n");



	if (disabled)