From patchwork Wed Sep 27 14:01:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joey Gouly X-Patchwork-Id: 13400853 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F0F2E80AAF for ; Wed, 27 Sep 2023 14:04:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232067AbjI0OEK (ORCPT ); Wed, 27 Sep 2023 10:04:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232065AbjI0OEI (ORCPT ); Wed, 27 Sep 2023 10:04:08 -0400 Received: from EUR05-VI1-obe.outbound.protection.outlook.com (mail-vi1eur05on2043.outbound.protection.outlook.com [40.107.21.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0D2C211D; Wed, 27 Sep 2023 07:04:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=CtQhUKKAeciLMz8eOcAzcWfX0r2cwo1XnqJpJwevaOw=; b=C3G5pwolId6E0/SNrrLGnc5x3R1MZyvrL8fUc//Aucc+Rp0cbtgWoO1K5JSvnE0gSgs8TUA6iLfslmrqm3K/UMw2ULdd8blsEcq93AxrzIUxSBETZH0fAiuBMhnSnTwNE4ly2I15D3fyE3naBrvVP0r/KwjmOtEw+zbbgMao6AA= Received: from AM0PR10CA0120.EURPRD10.PROD.OUTLOOK.COM (2603:10a6:208:e6::37) by DB3PR08MB10336.eurprd08.prod.outlook.com (2603:10a6:10:43b::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6813.28; Wed, 27 Sep 2023 14:04:01 +0000 Received: from AM7EUR03FT010.eop-EUR03.prod.protection.outlook.com (2603:10a6:208:e6:cafe::bd) by AM0PR10CA0120.outlook.office365.com (2603:10a6:208:e6::37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6792.35 via Frontend Transport; Wed, 27 Sep 2023 14:04:00 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 63.35.35.123) smtp.mailfrom=arm.com; dkim=pass (signature was verified) header.d=armh.onmicrosoft.com;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 63.35.35.123 as permitted sender) receiver=protection.outlook.com; client-ip=63.35.35.123; helo=64aa7808-outbound-1.mta.getcheckrecipient.com; pr=C Received: from 64aa7808-outbound-1.mta.getcheckrecipient.com (63.35.35.123) by AM7EUR03FT010.mail.protection.outlook.com (100.127.141.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6838.21 via Frontend Transport; Wed, 27 Sep 2023 14:03:59 +0000 Received: ("Tessian outbound 0ae75d4034ba:v211"); Wed, 27 Sep 2023 14:03:59 +0000 X-CheckRecipientChecked: true X-CR-MTA-CID: 8c0c49c206008a61 X-CR-MTA-TID: 64aa7808 Received: from e06e0c146651.1 by 64aa7808-outbound-1.mta.getcheckrecipient.com id 705B4AD0-0930-4F3A-A271-0479D60E97DC.1; Wed, 27 Sep 2023 14:01:54 +0000 Received: from EUR01-DB5-obe.outbound.protection.outlook.com by 64aa7808-outbound-1.mta.getcheckrecipient.com with ESMTPS id e06e0c146651.1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384); Wed, 27 Sep 2023 14:01:54 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=iTgipIyIGLUaqx8CnxNrhipBpXF/SlrTYhzx+lH3ilrA1+fF0PQmV+dG+MuIuVXfkobWhfBqy1LhokCWi6HOyUjX9a+TkB4qGNQz9lDmyeTlBtAqEQNwVVawk1RdrWNP4cwftkiefK9xaQ+dDmShdj3mdZ/8RTNNGb667Tf8kfezTjGYnHr76peXYeG5+hN2q+UL+IVqj8Pyx3KxjFAZsx3TLeD9qKRBdRwCR56l94es7tudaEt9n0CF+adVncu6ptJalZKKxDbyZFoiFiUhZ/j1JlPOIbIp/WCdyDK5jJXg9jMEQ0dJpxuOc2tQEGzOLmf/9+n/qfgha3idczB79A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=CtQhUKKAeciLMz8eOcAzcWfX0r2cwo1XnqJpJwevaOw=; b=VKAOf1uaRWHTU7wrOMiDdqGz9B8/CKRUVV77bPVlDM/zZZV4/4RRDeUCJfLDzOKmqwBuyPKLR3ZVvksBkIx3a1ojM/zcFyURIWRZ67JyyBeqKllZmAq9Yc5zdt6s8+SNHTZgGplOkY+5j0TBR+GJOXBJg3w36F88JLbTSaPZjmS865rVtRoDkDjnYKmATneYozMd+1WU6VIbs050S03jlleqbK6M+95WkFQC9rtXvL+oYC/dyxdqZRuAp/vi+hjCfCMQ3Xu4IK1iB65EyGzZG9ijFUuSvuuMOFBoQ25krnwwo4zPSNHwOyioyLUhFzZNBtJpav1PYSevnqjC+NUWiA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 40.67.248.234) smtp.rcpttodomain=lists.infradead.org smtp.mailfrom=arm.com; dmarc=pass (p=none sp=none pct=100) action=none header.from=arm.com; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector2-armh-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=CtQhUKKAeciLMz8eOcAzcWfX0r2cwo1XnqJpJwevaOw=; b=C3G5pwolId6E0/SNrrLGnc5x3R1MZyvrL8fUc//Aucc+Rp0cbtgWoO1K5JSvnE0gSgs8TUA6iLfslmrqm3K/UMw2ULdd8blsEcq93AxrzIUxSBETZH0fAiuBMhnSnTwNE4ly2I15D3fyE3naBrvVP0r/KwjmOtEw+zbbgMao6AA= Received: from AS9PR05CA0256.eurprd05.prod.outlook.com (2603:10a6:20b:493::23) by PA4PR08MB7595.eurprd08.prod.outlook.com (2603:10a6:102:271::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6813.28; Wed, 27 Sep 2023 14:01:52 +0000 Received: from AM7EUR03FT046.eop-EUR03.prod.protection.outlook.com (2603:10a6:20b:493:cafe::a2) by AS9PR05CA0256.outlook.office365.com (2603:10a6:20b:493::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6838.21 via Frontend Transport; Wed, 27 Sep 2023 14:01:52 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 40.67.248.234) smtp.mailfrom=arm.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 40.67.248.234 as permitted sender) receiver=protection.outlook.com; client-ip=40.67.248.234; helo=nebula.arm.com; pr=C Received: from nebula.arm.com (40.67.248.234) by AM7EUR03FT046.mail.protection.outlook.com (100.127.140.78) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.6838.22 via Frontend Transport; Wed, 27 Sep 2023 14:01:52 +0000 Received: from AZ-NEU-EX03.Arm.com (10.251.24.31) by AZ-NEU-EX04.Arm.com (10.251.24.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Wed, 27 Sep 2023 14:01:39 +0000 Received: from e124191.cambridge.arm.com (10.1.197.45) by mail.arm.com (10.251.24.31) with Microsoft SMTP Server id 15.1.2507.27 via Frontend Transport; Wed, 27 Sep 2023 14:01:39 +0000 From: Joey Gouly To: CC: , , , , , , , , , , , , , Subject: [PATCH v1 12/20] arm64: handle PKEY/POE faults Date: Wed, 27 Sep 2023 15:01:15 +0100 Message-ID: <20230927140123.5283-13-joey.gouly@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230927140123.5283-1-joey.gouly@arm.com> References: <20230927140123.5283-1-joey.gouly@arm.com> MIME-Version: 1.0 X-EOPAttributedMessage: 1 X-MS-TrafficTypeDiagnostic: AM7EUR03FT046:EE_|PA4PR08MB7595:EE_|AM7EUR03FT010:EE_|DB3PR08MB10336:EE_ X-MS-Office365-Filtering-Correlation-Id: 3b4df554-8f9d-463c-cade-08dbbf6298c1 x-checkrecipientrouted: true NoDisclaimer: true X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0; X-Microsoft-Antispam-Message-Info-Original: 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 X-Forefront-Antispam-Report-Untrusted: CIP:40.67.248.234;CTRY:IE;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:nebula.arm.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230031)(4636009)(136003)(346002)(396003)(39860400002)(376002)(230922051799003)(186009)(451199024)(1800799009)(82310400011)(40470700004)(36840700001)(46966006)(2906002)(36756003)(86362001)(40480700001)(5660300002)(44832011)(26005)(70206006)(54906003)(70586007)(2616005)(336012)(316002)(1076003)(426003)(41300700001)(6916009)(478600001)(7696005)(8676002)(4326008)(8936002)(47076005)(40460700003)(82740400003)(356005)(6666004)(36860700001)(81166007)(83380400001)(7416002)(36900700001);DIR:OUT;SFP:1101; X-MS-Exchange-Transport-CrossTenantHeadersStamped: PA4PR08MB7595 X-MS-Exchange-Transport-CrossTenantHeadersStripped: AM7EUR03FT010.eop-EUR03.prod.protection.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: 4725d3bd-55f8-4bd3-0ad8-08dbbf624d42 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: gdNe05r38aQCz2WtmnmkXPl3beeToRCdkxNT0Q3e8d+ti637z5CKQjkFC3NfQIXmutx2LOMID4T/pbQkOgPxQmyFSMcEqVl9eJ6JPSfaACBXExLcDMoH4Kkoy7k8N5+2gtM5SFDi8TjowlWdR1GOBltnkn5wKHnWSf4rHmw9rZH4QTjQBRg4Pb5Jwq88Z6lJTwq+GTUhxtmnStiPF4WuhIwZsbr/9W25fC+XUWsjx++J95bO1soBSD7VJrzlEuK5LjD+KK0G7QPFX9clDR3GJVXeDohz64tEljntJgpZ9ttTc2alos0PiTXFh+e/ffWUILYQ13MhqEw6eNcdS0DculnhJ+nfhuI2fT+EYoLkKJX4aCzylT0TtAcMmWjidlKeiobnsANJEgTWkaww3/yV8K6MZnTcJ1pl5Fu0QlkGtWzjXv+gez0NAtA0X0/qg3BNcXtZ6elpUIBqKx9PlZRCtUeuNSMOEP/UeKFV/gISjwdpYMd/54QCjDZ/KfB3UsAcd9PQv4J61wgNyn7ZvyFX+cCAw5LlwulTuE67L9huqr4yrPNynSjmVkRBB+Rzc/0dJrEcJdr0nTpbIoGJ0Cdmb1B/klGcL0x+7lJxnzI3JUWdS6ZsaXGw2QHp3zm/9KbJ7XETR5FcprXWwP4R7IBm394ALmFmDAHaLy/XrzJRMk9tBRP1s1WyMe5SceK+0VkFNIcWblv0kEKLYI3NWjaup7EYj5/YKV+sv0GNvkUw0+jMYP4b+rlN3FF8sy/e+Xvs X-Forefront-Antispam-Report: CIP:63.35.35.123;CTRY:IE;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:64aa7808-outbound-1.mta.getcheckrecipient.com;PTR:ec2-63-35-35-123.eu-west-1.compute.amazonaws.com;CAT:NONE;SFS:(13230031)(4636009)(136003)(346002)(396003)(39860400002)(376002)(230922051799003)(186009)(451199024)(1800799009)(82310400011)(40470700004)(36840700001)(46966006)(2906002)(36756003)(86362001)(40480700001)(5660300002)(44832011)(26005)(70206006)(54906003)(70586007)(2616005)(336012)(450100002)(6862004)(316002)(1076003)(426003)(41300700001)(478600001)(7696005)(8676002)(4326008)(8936002)(47076005)(40460700003)(82740400003)(6666004)(36860700001)(81166007)(83380400001);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Sep 2023 14:03:59.2813 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 3b4df554-8f9d-463c-cade-08dbbf6298c1 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT010.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB3PR08MB10336 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org If a memory fault occurs that is due to an overlay/pkey fault, report that to userspace with a SEGV_PKUERR. Signed-off-by: Joey Gouly Cc: Catalin Marinas Cc: Will Deacon --- arch/arm64/include/asm/traps.h | 1 + arch/arm64/kernel/traps.c | 12 ++++++++-- arch/arm64/mm/fault.c | 44 +++++++++++++++++++++++++++++++--- 3 files changed, 52 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h index d66dfb3a72dd..dae51eccfc19 100644 --- a/arch/arm64/include/asm/traps.h +++ b/arch/arm64/include/asm/traps.h @@ -26,6 +26,7 @@ try_emulate_armv8_deprecated(struct pt_regs *regs, u32 insn) void force_signal_inject(int signal, int code, unsigned long address, unsigned long err); void arm64_notify_segfault(unsigned long addr); void arm64_force_sig_fault(int signo, int code, unsigned long far, const char *str); +void arm64_force_sig_fault_pkey(int signo, int code, unsigned long far, const char *str, int pkey); void arm64_force_sig_mceerr(int code, unsigned long far, short lsb, const char *str); void arm64_force_sig_ptrace_errno_trap(int errno, unsigned long far, const char *str); diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 8b70759cdbb9..b68682c284a2 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -263,16 +263,24 @@ static void arm64_show_signal(int signo, const char *str) __show_regs(regs); } -void arm64_force_sig_fault(int signo, int code, unsigned long far, - const char *str) +void arm64_force_sig_fault_pkey(int signo, int code, unsigned long far, + const char *str, int pkey) { arm64_show_signal(signo, str); if (signo == SIGKILL) force_sig(SIGKILL); + else if (code == SEGV_PKUERR) + force_sig_pkuerr((void __user *)far, pkey); else force_sig_fault(signo, code, (void __user *)far); } +void arm64_force_sig_fault(int signo, int code, unsigned long far, + const char *str) +{ + arm64_force_sig_fault_pkey(signo, code, far, str, 0); +} + void arm64_force_sig_mceerr(int code, unsigned long far, short lsb, const char *str) { diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 2e5d1e238af9..a76906199479 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #include @@ -497,6 +498,23 @@ static void do_bad_area(unsigned long far, unsigned long esr, #define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000) #define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000) +static bool fault_from_pkey(unsigned long esr, struct vm_area_struct *vma, + unsigned int mm_flags) +{ + unsigned long iss2 = ESR_ELx_ISS2(esr); + + if (!arch_pkeys_enabled()) + return false; + + if (iss2 & ESR_ELx_Overlay) + return true; + + return !arch_vma_access_permitted(vma, + mm_flags & FAULT_FLAG_WRITE, + mm_flags & FAULT_FLAG_INSTRUCTION, + mm_flags & FAULT_FLAG_REMOTE); +} + static vm_fault_t __do_page_fault(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr, unsigned int mm_flags, unsigned long vm_flags, @@ -688,9 +706,29 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, * Something tried to access memory that isn't in our memory * map. */ - arm64_force_sig_fault(SIGSEGV, - fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR, - far, inf->name); + int fault_kind; + /* + * The pkey value that we return to userspace can be different + * from the pkey that caused the fault. + * + * 1. T1 : mprotect_key(foo, PAGE_SIZE, pkey=4); + * 2. T1 : set AMR to deny access to pkey=4, touches, page + * 3. T1 : faults... + * 4. T2: mprotect_key(foo, PAGE_SIZE, pkey=5); + * 5. T1 : enters fault handler, takes mmap_lock, etc... + * 6. T1 : reaches here, sees vma_pkey(vma)=5, when we really + * faulted on a pte with its pkey=4. + */ + int pkey = vma_pkey(vma); + + if (fault_from_pkey(esr, vma, mm_flags)) + fault_kind = SEGV_PKUERR; + else + fault_kind = fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR; + + arm64_force_sig_fault_pkey(SIGSEGV, + fault_kind, + far, inf->name, pkey); } return 0;