From patchwork Wed Jun 24 20:23:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Collin Walling X-Patchwork-Id: 1316547 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 49sZX85JGyz9sRW for ; Thu, 25 Jun 2020 06:30:15 +1000 (AEST) Received: from localhost ([::1]:34994 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1joC27-00074T-Qr for incoming@patchwork.ozlabs.org; Wed, 24 Jun 2020 16:30:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55050) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1joBvy-0006No-VK; Wed, 24 Jun 2020 16:23:50 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:36396) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1joBvv-00032S-OU; Wed, 24 Jun 2020 16:23:50 -0400 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 05OK3OcK105345; Wed, 24 Jun 2020 16:23:46 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 31vbmtbt20-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 Jun 2020 16:23:45 -0400 Received: from m0098404.ppops.net (m0098404.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 05OK4Ofm112346; Wed, 24 Jun 2020 16:23:45 -0400 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 31vbmtbt14-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 Jun 2020 16:23:45 -0400 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 05OKJWaq012586; Wed, 24 Jun 2020 20:23:42 GMT Received: from b01cxnp23034.gho.pok.ibm.com (b01cxnp23034.gho.pok.ibm.com [9.57.198.29]) by ppma04dal.us.ibm.com with ESMTP id 31uurq06jf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 Jun 2020 20:23:42 +0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 05OKNfjG50856370 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 24 Jun 2020 20:23:41 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A6295AE060; Wed, 24 Jun 2020 20:23:41 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 73582AE062; Wed, 24 Jun 2020 20:23:41 +0000 (GMT) Received: from localhost.localdomain.com (unknown [9.85.198.108]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 24 Jun 2020 20:23:41 +0000 (GMT) From: Collin Walling To: qemu-devel@nongnu.org, qemu-s390x@nongnu.org Subject: [PATCH v4 3/8] s390/sclp: rework sclp boundary and length checks Date: Wed, 24 Jun 2020 16:23:07 -0400 Message-Id: <20200624202312.28349-4-walling@linux.ibm.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200624202312.28349-1-walling@linux.ibm.com> References: <20200624202312.28349-1-walling@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216, 18.0.687 definitions=2020-06-24_16:2020-06-24, 2020-06-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 malwarescore=0 bulkscore=0 impostorscore=0 suspectscore=0 adultscore=0 spamscore=0 phishscore=0 clxscore=1015 cotscore=-2147483648 mlxlogscore=999 lowpriorityscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006240129 Received-SPF: pass client-ip=148.163.156.1; envelope-from=walling@linux.ibm.com; helo=mx0a-001b2d01.pphosted.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/24 15:31:11 X-ACL-Warn: Detected OS = Linux 3.x [generic] [fuzzy] X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: thuth@redhat.com, frankja@linux.ibm.com, david@redhat.com, cohuck@redhat.com, pasic@linux.ibm.com, borntraeger@de.ibm.com, mst@redhat.com, svens@linux.ibm.com, pbonzini@redhat.com, mihajlov@linux.ibm.com, rth@twiddle.net Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Rework the SCLP boundary check to account for different SCLP commands (eventually) allowing different boundary sizes. Move the length check code into a separate function, and introduce a new function to determine the length of the read SCP data (i.e. the size from the start of the struct to where the CPU entries should begin). The format of read CPU info is unlikely to change in the future, so we do not require a separate function to calculate its length. Signed-off-by: Collin Walling Acked-by: Janosch Frank Reviewed-by: Cornelia Huck Reviewed-by: Thomas Huth --- hw/s390x/sclp.c | 54 ++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 44 insertions(+), 10 deletions(-) diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c index 181ce04007..5899c1e3b8 100644 --- a/hw/s390x/sclp.c +++ b/hw/s390x/sclp.c @@ -49,6 +49,34 @@ static inline bool sclp_command_code_valid(uint32_t code) return false; } +static bool sccb_verify_boundary(uint64_t sccb_addr, uint32_t code, + SCCBHeader *header) +{ + uint64_t sccb_max_addr = sccb_addr + be16_to_cpu(header->length) - 1; + uint64_t sccb_boundary = (sccb_addr & PAGE_MASK) + PAGE_SIZE; + + switch (code & SCLP_CMD_CODE_MASK) { + default: + if (sccb_max_addr < sccb_boundary) { + return true; + } + } + header->response_code = cpu_to_be16(SCLP_RC_SCCB_BOUNDARY_VIOLATION); + return false; +} + +/* Calculates sufficient SCCB length to store a full Read SCP/CPU response */ +static bool sccb_verify_length(SCCB *sccb, int num_cpus, int offset_cpu) +{ + int required_len = offset_cpu + num_cpus * sizeof(CPUEntry); + + if (be16_to_cpu(sccb->h.length) < required_len) { + sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); + return false; + } + return true; +} + static void prepare_cpu_entries(MachineState *ms, CPUEntry *entry, int *count) { uint8_t features[SCCB_CPU_FEATURE_LEN] = { 0 }; @@ -66,6 +94,11 @@ static void prepare_cpu_entries(MachineState *ms, CPUEntry *entry, int *count) } } +static inline int get_read_scp_info_offset_cpu(void) +{ + return offsetof(ReadInfo, entries); +} + /* Provide information about the configuration, CPUs and storage */ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb) { @@ -74,17 +107,16 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb) int cpu_count; int rnsize, rnmax; IplParameterBlock *ipib = s390_ipl_get_iplb(); + int offset_cpu = get_read_scp_info_offset_cpu(); - if (be16_to_cpu(sccb->h.length) < - (sizeof(ReadInfo) + machine->possible_cpus->len * sizeof(CPUEntry))) { - sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); + if (!sccb_verify_length(sccb, machine->possible_cpus->len, offset_cpu)) { return; } /* CPU information */ prepare_cpu_entries(machine, read_info->entries, &cpu_count); read_info->entries_cpu = cpu_to_be16(cpu_count); - read_info->offset_cpu = cpu_to_be16(offsetof(ReadInfo, entries)); + read_info->offset_cpu = cpu_to_be16(offset_cpu); read_info->highest_cpu = cpu_to_be16(machine->smp.max_cpus - 1); read_info->ibc_val = cpu_to_be32(s390_get_ibc_val()); @@ -133,17 +165,16 @@ static void sclp_read_cpu_info(SCLPDevice *sclp, SCCB *sccb) { MachineState *machine = MACHINE(qdev_get_machine()); ReadCpuInfo *cpu_info = (ReadCpuInfo *) sccb; + int offset_cpu = offsetof(ReadCpuInfo, entries); int cpu_count; - if (be16_to_cpu(sccb->h.length) < - (sizeof(ReadInfo) + machine->possible_cpus->len * sizeof(CPUEntry))) { - sccb->h.response_code = cpu_to_be16(SCLP_RC_INSUFFICIENT_SCCB_LENGTH); + if (!sccb_verify_length(sccb, machine->possible_cpus->len, offset_cpu)) { return; } prepare_cpu_entries(machine, cpu_info->entries, &cpu_count); cpu_info->nr_configured = cpu_to_be16(cpu_count); - cpu_info->offset_configured = cpu_to_be16(offsetof(ReadCpuInfo, entries)); + cpu_info->offset_configured = cpu_to_be16(offset_cpu); cpu_info->nr_standby = cpu_to_be16(0); /* The standby offset is 16-byte for each CPU */ @@ -229,6 +260,10 @@ int sclp_service_call_protected(CPUS390XState *env, uint64_t sccb, goto out_write; } + if (!sccb_verify_boundary(sccb, code, &work_sccb.h)) { + goto out_write; + } + sclp_c->execute(sclp, &work_sccb, code); out_write: s390_cpu_pv_mem_write(env_archcpu(env), 0, &work_sccb, @@ -274,8 +309,7 @@ int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code) goto out_write; } - if ((sccb + be16_to_cpu(work_sccb.h.length)) > ((sccb & PAGE_MASK) + PAGE_SIZE)) { - work_sccb.h.response_code = cpu_to_be16(SCLP_RC_SCCB_BOUNDARY_VIOLATION); + if (!sccb_verify_boundary(sccb, code, &work_sccb.h)) { goto out_write; }