Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753356AbdGEV0W (ORCPT ); Wed, 5 Jul 2017 17:26:22 -0400 Received: from mail-qt0-f194.google.com ([209.85.216.194]:36515 "EHLO mail-qt0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752445AbdGEVXt (ORCPT ); Wed, 5 Jul 2017 17:23:49 -0400 From: Ram Pai To: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.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, dave.hansen@intel.com, hbabu@us.ibm.com, linuxram@us.ibm.com, arnd@arndb.de, akpm@linux-foundation.org, corbet@lwn.net, mingo@redhat.com Subject: [RFC v5 33/38] powerpc: Deliver SEGV signal on pkey violation Date: Wed, 5 Jul 2017 14:22:10 -0700 Message-Id: <1499289735-14220-34-git-send-email-linuxram@us.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1499289735-14220-1-git-send-email-linuxram@us.ibm.com> References: <1499289735-14220-1-git-send-email-linuxram@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3302 Lines: 101 The value of the AMR register at the time of exception is made available in gp_regs[PT_AMR] of the siginfo. The value of the pkey, whose protection got violated, is made available in si_pkey field of the siginfo structure. Signed-off-by: Ram Pai --- arch/powerpc/include/uapi/asm/ptrace.h | 3 ++- arch/powerpc/kernel/signal_32.c | 5 +++++ arch/powerpc/kernel/signal_64.c | 4 ++++ arch/powerpc/kernel/traps.c | 14 ++++++++++++++ 4 files changed, 25 insertions(+), 1 deletions(-) diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h index 8036b38..7ec2428 100644 --- a/arch/powerpc/include/uapi/asm/ptrace.h +++ b/arch/powerpc/include/uapi/asm/ptrace.h @@ -108,8 +108,9 @@ struct pt_regs { #define PT_DAR 41 #define PT_DSISR 42 #define PT_RESULT 43 -#define PT_DSCR 44 #define PT_REGS_COUNT 44 +#define PT_DSCR 44 +#define PT_AMR 45 #define PT_FPR0 48 /* each FP reg occupies 2 slots in this space */ diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 97bb138..9c4a7f3 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -500,6 +500,11 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, (unsigned long) &frame->tramp[2]); } +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS + if (__put_user(get_paca()->paca_amr, &frame->mc_gregs[PT_AMR])) + return 1; +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ + return 0; } diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index c83c115..86a4262 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -174,6 +174,10 @@ static long setup_sigcontext(struct sigcontext __user *sc, if (set != NULL) err |= __put_user(set->sig[0], &sc->oldmask); +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS + err |= __put_user(get_paca()->paca_amr, &sc->gp_regs[PT_AMR]); +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ + return err; } diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index d4e545d..cc0a8c4 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -247,6 +248,14 @@ void user_single_step_siginfo(struct task_struct *tsk, info->si_addr = (void __user *)regs->nip; } +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS +static void fill_sig_info_pkey(int si_code, siginfo_t *info, unsigned long addr) +{ + WARN_ON(si_code != SEGV_PKUERR); + info->si_pkey = get_paca()->paca_pkey; +} +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ + void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) { siginfo_t info; @@ -274,6 +283,11 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) info.si_signo = signr; info.si_code = code; info.si_addr = (void __user *) addr; + +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS + fill_sig_info_pkey(code, &info, addr); +#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */ + force_sig_info(signr, &info, current); } -- 1.7.1