From patchwork Thu Nov 5 13:47:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 11884429 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24939C4741F for ; Thu, 5 Nov 2020 13:48:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA332206B6 for ; Thu, 5 Nov 2020 13:48:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727275AbgKENsR convert rfc822-to-8bit (ORCPT ); Thu, 5 Nov 2020 08:48:17 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:60550 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725468AbgKENsQ (ORCPT ); Thu, 5 Nov 2020 08:48:16 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0A5DljqF176172; Thu, 5 Nov 2020 08:47:53 -0500 Received: from ppma04fra.de.ibm.com (6a.4a.5195.ip4.static.sl-reverse.com [149.81.74.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 34m5ftekvw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 05 Nov 2020 08:47:52 -0500 Received: from pps.filterd (ppma04fra.de.ibm.com [127.0.0.1]) by ppma04fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 0A5DiBvH006410; Thu, 5 Nov 2020 13:47:26 GMT Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by ppma04fra.de.ibm.com with ESMTP id 34h0f6tt1m-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 05 Nov 2020 13:47:26 +0000 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0A5DlNMp64487700 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 5 Nov 2020 13:47:23 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CDF76A4054; Thu, 5 Nov 2020 13:47:23 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7CFFBA405B; Thu, 5 Nov 2020 13:47:23 +0000 (GMT) Received: from smtp.tlslab.ibm.com (unknown [9.101.4.1]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with SMTP; Thu, 5 Nov 2020 13:47:23 +0000 (GMT) Received: from yukon.ibmuc.com (sig-9-145-56-119.uk.ibm.com [9.145.56.119]) by smtp.tlslab.ibm.com (Postfix) with ESMTP id 3776422006B; Thu, 5 Nov 2020 14:47:22 +0100 (CET) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: Paul Mackerras Cc: linuxppc-dev@lists.ozlabs.org, Michael Ellerman , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, Greg Kurz , Gustavo Romero , David Gibson , =?utf-8?q?C=C3=A9dric_Le_Goater?= Subject: [PATCH] KVM: PPC: Book3S HV: XIVE: Fix possible oops when accessing ESB page Date: Thu, 5 Nov 2020 14:47:13 +0100 Message-Id: <20201105134713.656160-1-clg@kaod.org> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-11-05_07:2020-11-05,2020-11-05 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 spamscore=0 mlxscore=0 phishscore=0 suspectscore=0 clxscore=1034 bulkscore=0 priorityscore=1501 mlxlogscore=648 adultscore=0 impostorscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011050088 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When accessing the ESB page of a source interrupt, the fault handler will retrieve the page address from the XIVE interrupt 'xive_irq_data' structure. If the associated KVM XIVE interrupt is not valid, that is not allocated at the HW level for some reason, the fault handler will dereference a NULL pointer leading to the oops below : WARNING: CPU: 40 PID: 59101 at arch/powerpc/kvm/book3s_xive_native.c:259 xive_native_esb_fault+0xe4/0x240 [kvm] CPU: 40 PID: 59101 Comm: qemu-system-ppc Kdump: loaded Tainted: G W --------- - - 4.18.0-240.el8.ppc64le #1 NIP: c00800000e949fac LR: c00000000044b164 CTR: c00800000e949ec8 REGS: c000001f69617840 TRAP: 0700 Tainted: G W --------- - - (4.18.0-240.el8.ppc64le) MSR: 9000000000029033 CR: 44044282 XER: 00000000 CFAR: c00000000044b160 IRQMASK: 0 GPR00: c00000000044b164 c000001f69617ac0 c00800000e96e000 c000001f69617c10 GPR04: 05faa2b21e000080 0000000000000000 0000000000000005 ffffffffffffffff GPR08: 0000000000000000 0000000000000001 0000000000000000 0000000000000001 GPR12: c00800000e949ec8 c000001ffffd3400 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 c000001f5c065160 c000000001c76f90 GPR24: c000001f06f20000 c000001f5c065100 0000000000000008 c000001f0eb98c78 GPR28: c000001dcab40000 c000001dcab403d8 c000001f69617c10 0000000000000011 NIP [c00800000e949fac] xive_native_esb_fault+0xe4/0x240 [kvm] LR [c00000000044b164] __do_fault+0x64/0x220 Call Trace: [c000001f69617ac0] [0000000137a5dc20] 0x137a5dc20 (unreliable) [c000001f69617b50] [c00000000044b164] __do_fault+0x64/0x220 [c000001f69617b90] [c000000000453838] do_fault+0x218/0x930 [c000001f69617bf0] [c000000000456f50] __handle_mm_fault+0x350/0xdf0 [c000001f69617cd0] [c000000000457b1c] handle_mm_fault+0x12c/0x310 [c000001f69617d10] [c00000000007ef44] __do_page_fault+0x264/0xbb0 [c000001f69617df0] [c00000000007f8c8] do_page_fault+0x38/0xd0 [c000001f69617e30] [c00000000000a714] handle_page_fault+0x18/0x38 Instruction dump: 40c2fff0 7c2004ac 2fa90000 409e0118 73e90001 41820080 e8bd0008 7c2004ac 7ca90074 39400000 915c0000 7929d182 <0b090000> 2fa50000 419e0080 e89e0018 ---[ end trace 66c6ff034c53f64f ]--- xive-kvm: xive_native_esb_fault: accessing invalid ESB page for source 8 ! Fix that by checking the validity of the KVM XIVE interrupt structure. Reported-by: Greg Kurz Signed-off-by: Cédric Le Goater Tested-by: Greg Kurz --- arch/powerpc/kvm/book3s_xive_native.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c index d0c2db0e07fa..a59a94f02733 100644 --- a/arch/powerpc/kvm/book3s_xive_native.c +++ b/arch/powerpc/kvm/book3s_xive_native.c @@ -251,6 +251,13 @@ static vm_fault_t xive_native_esb_fault(struct vm_fault *vmf) } state = &sb->irq_state[src]; + + /* Some sanity checking */ + if (!state->valid) { + pr_devel("%s: source %lx invalid !\n", __func__, irq); + return VM_FAULT_SIGBUS; + } + kvmppc_xive_select_irq(state, &hw_num, &xd); arch_spin_lock(&sb->lock);