From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell Currey Subject: [PATCH 5/7] powerpc/mm/radix: Use KUEP API for Radix MMU Date: Thu, 21 Feb 2019 20:35:59 +1100 Message-Id: <20190221093601.27920-6-ruscur@russell.cc> In-Reply-To: <20190221093601.27920-1-ruscur@russell.cc> References: <20190221093601.27920-1-ruscur@russell.cc> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: linuxppc-dev@lists.ozlabs.org Cc: mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@c-s.fr, kernel-hardening@lists.openwall.com, Russell Currey List-ID: Execution protection already exists on radix, this just refactors the radix init to provide the KUEP setup function instead. Thus, the only functional change is that it can now be disabled. Signed-off-by: Russell Currey --- arch/powerpc/mm/pgtable-radix.c | 12 +++++++++--- arch/powerpc/platforms/Kconfig.cputype | 1 + 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index 931156069a81..224bcd4be5ae 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -535,8 +535,15 @@ static void radix_init_amor(void) mtspr(SPRN_AMOR, (3ul << 62)); } -static void radix_init_iamr(void) +#ifdef CONFIG_PPC_KUEP +void __init setup_kuep(bool disabled) { + if (disabled || !early_radix_enabled()) + return; + + if (smp_processor_id() == boot_cpuid) + pr_info("Activating Kernel Userspace Execution Prevention\n"); + /* * Radix always uses key0 of the IAMR to determine if an access is * allowed. We set bit 0 (IBM bit 1) of key0, to prevent instruction @@ -544,6 +551,7 @@ static void radix_init_iamr(void) */ mtspr(SPRN_IAMR, (1ul << 62)); } +#endif void __init radix__early_init_mmu(void) { @@ -605,7 +613,6 @@ void __init radix__early_init_mmu(void) memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); - radix_init_iamr(); radix_init_pgtable(); /* Switch to the guard PID before turning on MMU */ radix__switch_mmu_context(NULL, &init_mm); @@ -627,7 +634,6 @@ void radix__early_init_mmu_secondary(void) __pa(partition_tb) | (PATB_SIZE_SHIFT - 12)); radix_init_amor(); } - radix_init_iamr(); radix__switch_mmu_context(NULL, &init_mm); if (cpu_has_feature(CPU_FTR_HVMODE)) diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 7fa5ddbdce12..25cc7d36b27d 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -320,6 +320,7 @@ config PPC_RADIX_MMU bool "Radix MMU Support" depends on PPC_BOOK3S_64 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA + select PPC_HAVE_KUEP default y help Enable support for the Power ISA 3.0 Radix style MMU. Currently this -- 2.20.1