From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x244.google.com (mail-qt0-x244.google.com [IPv6:2607:f8b0:400d:c0d::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xLKfG4RH4zDr5s for ; Mon, 31 Jul 2017 10:12:54 +1000 (AEST) Received: by mail-qt0-x244.google.com with SMTP id d10so15667408qtb.4 for ; Sun, 30 Jul 2017 17:12:54 -0700 (PDT) Sender: Ram Pai From: Ram Pai To: linuxppc-dev@lists.ozlabs.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, linuxram@us.ibm.com, bauerman@linux.vnet.ibm.com, mhocko@kernel.org Subject: [RFC v7 08/25] powerpc: ability to create execute-disabled pkeys Date: Sun, 30 Jul 2017 17:12:09 -0700 Message-Id: <1501459946-11619-9-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1501459946-11619-1-git-send-email-linuxram@us.ibm.com> References: <1501459946-11619-1-git-send-email-linuxram@us.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , powerpc has hardware support to disable execute on a pkey. This patch enables the ability to create execute-disabled keys. Signed-off-by: Ram Pai --- arch/powerpc/include/asm/pkeys.h | 12 ++++++++++++ arch/powerpc/mm/pkeys.c | 5 +++++ 2 files changed, 17 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h index aec3f49..9d59619 100644 --- a/arch/powerpc/include/asm/pkeys.h +++ b/arch/powerpc/include/asm/pkeys.h @@ -22,6 +22,18 @@ #define VM_PKEY_BIT4 VM_HIGH_ARCH_4 #endif +/* override any generic PKEY Permission defines */ +#undef PKEY_DISABLE_ACCESS +#define PKEY_DISABLE_ACCESS 0x1 +#undef PKEY_DISABLE_WRITE +#define PKEY_DISABLE_WRITE 0x2 +#undef PKEY_DISABLE_EXECUTE +#define PKEY_DISABLE_EXECUTE 0x4 +#undef PKEY_ACCESS_MASK +#define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\ + PKEY_DISABLE_WRITE |\ + PKEY_DISABLE_EXECUTE) + #define arch_max_pkey() pkeys_total #define AMR_RD_BIT 0x1UL #define AMR_WR_BIT 0x2UL diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c index 5b3531e..c1c40c3 100644 --- a/arch/powerpc/mm/pkeys.c +++ b/arch/powerpc/mm/pkeys.c @@ -78,6 +78,7 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long init_val) { u64 new_amr_bits = 0x0ul; + u64 new_iamr_bits = 0x0ul; if (!is_pkey_enabled(pkey)) return -EINVAL; @@ -90,5 +91,9 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey, init_amr(pkey, new_amr_bits); + if ((init_val & PKEY_DISABLE_EXECUTE)) + new_iamr_bits |= IAMR_EX_BIT; + + init_iamr(pkey, new_iamr_bits); return 0; } -- 1.7.1