From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C62F2C17B6 for ; Thu, 18 Sep 2025 18:07:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=148.163.158.5 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758218852; cv=fail; b=OwyOYGk71J+BhI0v53wBHfIOK0U/9IvfPtQkcrSEQfwhNA91AynLNXf4lO3QeNca3EQ5CS6q3vintohpLMFCQuUzfAzXmu3oHXs8r16ySvNymbayApbMA6gvJF7+efaGBZ9CW4Ei4OxkZ6Edtf3TZ8eIsJTZ1TQ2+aI+vQ9gqao= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758218852; c=relaxed/simple; bh=ld9ltvb/l0tpqzvyyTsW+rk9vOLAaPMojxpX3FGwJcs=; h=From:To:CC:Date:Message-ID:References:In-Reply-To:Content-Type: MIME-Version:Subject; b=H2s/Rxc1wViycjwkFFvkWKQsJe+ffY/0urOs3HpzJaGl/QH/bDkdZufeA1WWfrv26ni97LLNrwIOIPqSeq25jPbTDFHP7TZevR3afNJ1fRtH6pXupOw9zLumc4HLj8z/580haSlAWOfrOcr/H88MKNQX9kiISFcZEzQ0uIzStX0= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ibm.com; spf=pass smtp.mailfrom=ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=axQlonk8; arc=fail smtp.client-ip=148.163.158.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="axQlonk8" Received: from pps.filterd (m0360072.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 58IFEUWe011266 for ; Thu, 18 Sep 2025 18:07:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-id:content-transfer-encoding:content-type:date:from :in-reply-to:message-id:mime-version:references:subject:to; s= pp1; bh=SMl9Xmy+ta/PoJTcRw7zTgo460v3TzjlAnnt5ng4bWg=; b=axQlonk8 wUGEBSIEVgVoI0TFoTSr9Eh0T+kAnnFffYpr3wuczgbbTZM0r0PckU6af9hk4a60 ifdPMTNZNGHlRTGev6mhwOI4nREqNsWabrT8iSKKM+b+Fm8pdJIyVQWohW2BjAdr YRpItLsFpv5Zpe6U/wOLfSQL/LAeHv/cXpGBGUZthRD7uqRUCDD2rDouHszCLqNy YzaQLJv7m0CHtjKWEm3jaz8KfhwCgz8IFoqbqXCvXPgBfR71VJGIVJR5CoZrF4BL EdULdQRwK57QR0/Fva0YwoRp7M27uPexZ1Bm24iQXFR5copioqGxcFMGDETUFFEl LZ06hy1DvQ8cLA== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 497g4nkj60-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Sep 2025 18:07:27 +0000 (GMT) Received: from m0360072.ppops.net (m0360072.ppops.net [127.0.0.1]) by pps.reinject (8.18.1.12/8.18.0.8) with ESMTP id 58II0Jxe023489; Thu, 18 Sep 2025 18:07:26 GMT Received: from mw6pr02cu001.outbound.protection.outlook.com (mail-westus2azon11012047.outbound.protection.outlook.com [52.101.48.47]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 497g4nkj5v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 Sep 2025 18:07:26 +0000 (GMT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=BwEpHVrzjyBCO7O+2mSOk+581zdD3ThWXvxsp0lnWYcFvqA6KmYY4ZGaqIPpoDlm28DIZAZIq/OauSdQBHMnq56umDvS9sM7hgdbppQqILwCUuaq/dkNxrpc0BV+wbrzPTxSccs1GJZukDTR7YL61iEo4K5J6+k3gSMNhHv1dF1RkrhIBU7M89a7I6vFgAVzXhwuW9HJmo97tAJzNU162DTfZ6lbz7ZTNHBkDr1Vr00mTc7H0z7Eht3QrEWM0VuY9bOmhh7CsJSREM2hrl8JtpwfF6xf7Jv8Hfh3TlwSQC+/8k7LK1ryUcRqwntSETy7r/7SjbHmy5GN6kn6nw1c5g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=y5fgl+USXztswL1dvi5mvdKPUiyvSceBDUO2aPiANbs=; b=xF2npkHmoTlH9R5hU9k3VJBdQWe7hCfvLK4W7WIdy+aObVnT2JfgGpStUaX8cgoqBttPPubpi72X5mOXz8CJqk4gESymVa5Z1bruzxRUbystQxxYVqWo/c3sCVGhRODwKIh+gC3Bf+LjeMnMi01b94k8IIz5xfq54iOC247Czi0B6KshUSy69tcMql4rsoN3PE9u67OpSYjaGd5FUwlHwaruEgSrmFdbMqlZLmvL3cYxEKyLGXe+4m+N1spGHXe7a12GwUF1slsabmI3TTeRS2FZAZjmlDioxmAh6VTY93F+O0lbuv/5w2JbGgEX7qJqmqAOKRoWfYTNs0bOHBMbow== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=ibm.com; dmarc=pass action=none header.from=ibm.com; dkim=pass header.d=ibm.com; arc=none Received: from SA1PR15MB5819.namprd15.prod.outlook.com (2603:10b6:806:338::8) by BY3PR15MB5057.namprd15.prod.outlook.com (2603:10b6:a03:3cc::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9137.13; Thu, 18 Sep 2025 18:07:23 +0000 Received: from SA1PR15MB5819.namprd15.prod.outlook.com ([fe80::6fd6:67be:7178:d89b]) by SA1PR15MB5819.namprd15.prod.outlook.com ([fe80::6fd6:67be:7178:d89b%3]) with mapi id 15.20.9094.021; Thu, 18 Sep 2025 18:07:23 +0000 From: Viacheslav Dubeyko To: "ceph-devel@vger.kernel.org" , "lyican53@gmail.com" CC: "idryomov@gmail.com" , Xiubo Li , "linux-kernel@vger.kernel.org" Thread-Topic: [EXTERNAL] [PATCH] ceph: Fix potential undefined behavior in crush_ln() with GCC 11.1.0 Thread-Index: AQHcKD62wAtpkSIONkKx6UhtKA1hyLSZPasA Date: Thu, 18 Sep 2025 18:07:23 +0000 Message-ID: References: <1AD55673-B7F4-4DB7-AE80-1AC81709F65A@gmail.com> In-Reply-To: <1AD55673-B7F4-4DB7-AE80-1AC81709F65A@gmail.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-publictraffictype: Email x-ms-traffictypediagnostic: SA1PR15MB5819:EE_|BY3PR15MB5057:EE_ x-ms-office365-filtering-correlation-id: 89e1cefc-c1d5-4254-3ee0-08ddf6de3782 x-ld-processed: fcf67057-50c9-4ad4-98f3-ffca64add9e9,ExtAddr x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0;ARA:13230040|1800799024|376014|366016|10070799003|38070700021; x-microsoft-antispam-message-info: =?utf-8?B?bnNiRTE0SjRBZnhaRmJ5TEVzR3Q2Mmd4cmY2ZnhuRUI3TEh3dG5rSDBlTlNv?= =?utf-8?B?MS9XRnRPMDV3akVxOFU2dGRUbytPWjJFM0REUkNCK3cwcjA5MFhvbU0raVp2?= =?utf-8?B?eHczUzJ2Ymx1WmdtMUF2eEU4WHJ6UkVzaEJqMWV0MThFQ013SGxUVWFDNE5O?= =?utf-8?B?N3lmTnVNMkYxZHo1aTBieXJZaFNTcUZUaXVYVzhLSXY4YllzSUNuNVY5RmUw?= =?utf-8?B?Zyt5Um5oTnRpT0Vpbjh2M2lkVjl2Z1hmcXZZemJwRjBhNkxtakpRY0hCUzl5?= =?utf-8?B?Ty82ZU9kcjdkd0JQK2NaR0RYOUM0dWVRUE9qQkZuVGRQVnFzTHliaDRwNnVt?= =?utf-8?B?ZWNqcGN3RWsrQ1dRYzBxUTlsL0YxcU43K0Q4T0Q4SUUxV0Z6M3d2dHdLSStj?= =?utf-8?B?Ump2QzdGNFAvZWtnc2g0QnR4NEFuZGNJMUFNcFZFSGNocERmcTFFNktwMXU1?= =?utf-8?B?L2hDOC9JNUU2Z3hpNU1Wa0h5ZXVsRy9ra1M1RzB1U0doa3ZiL2hFajVjV1dj?= =?utf-8?B?TjNGekxIS0NMV0VBRDRqbkdESHBTc3JvMzJkU29WcU9xczBaYzgvWVRobkZH?= =?utf-8?B?YUlobWRYWTZMSXpBaU1TUS9qVTdnRGxYc2Q2WDNndXV2SHlRdVVKVkNadlha?= =?utf-8?B?MHBVRGNnZzV5d2UvOTFNb2NTNWliTGxJUFRsSnZ5dDV6SUFUMndLWTZ1eW1n?= =?utf-8?B?YjJmRUFOZmFmcXY3RDB3U00xUFZqS1VSV2Rxb0xKWEdGdTNHMzJXSjVmZEl3?= =?utf-8?B?MGozei94dEhlZ0FZZHI3TGhLbVZ6ckF4SlY2QUxIUndqa25jaXZ4eGlnUUtW?= =?utf-8?B?cXRUSkVFN0VOVm1DWEsvcXBWRmVyaTZ1U0VzOGk3WE1uaDUrSXN3eGM5T2Fs?= =?utf-8?B?enp0SGlVUjB4akw2TUNOOVQrM3lkRkl6QldlbE9CQ1QzK0FSdkp6WVVDQUNB?= =?utf-8?B?cGt3WGxhWWlJckp5MTVEUHhuREFCVXZFVVpJZDJiNlhMeFJDc25td1BrVkNp?= =?utf-8?B?K3g1VGViOGxVMjdnNUNmbmNLSEpxYWZ6WFN2ZWFzN0xPRmxheGZIRzBHampv?= =?utf-8?B?ZldkM1NWTVpxSjFncjdlb01mY0hhYnpiVXJhcW4wMUhsVmpnZlJTa0tyTTZo?= =?utf-8?B?VnB6a3hzY2VnUEpmSEN5Zmh0bWs2ei9TVmlndVpjZHpuZ2h3SXIvM3E1anA4?= =?utf-8?B?blY5S1QrWGdra2diTEhFeHNINmh0Y3ZQTlBaMU9qN29JQUVRNDd6ZFlIZFpk?= =?utf-8?B?VjUvUytqZUdZaSthUy8rQWFTdEJTcVlzc016TzRZbWl6ZlQrSXBKNUZYSE9w?= =?utf-8?B?TjNsR3ZzUDZ0MHI5VUErZVJjUnNzbGF6TDB2ekRhK2JaNWg1YnZ4dEJPNUtP?= =?utf-8?B?dTE1clNWM2JmdUdUUktxeFE1SFpQMnFKQTBxbEpub0lBS29aSlQ0OE9XQW9p?= =?utf-8?B?cXljTVd0UGVyVmxrQlZwZnV2bWNDWi9hMUsxamZPZ1poTk9oM3Z2REtrM2FD?= =?utf-8?B?ZSt0aXpyTmlqdnJPMHZOMmtlc3JIb1FxVGVaQktCbEozYUNSTDdqaWh1aUli?= =?utf-8?B?SDFjNFE2S3lJNyt6aDhWbmJPODRPVnRIN1ZCRUg1SXdZNFQ5RUE1T2h2L29x?= =?utf-8?B?eGs4ck11SVdZV3Q2QVpQejl6Y2ZleUpmeko3OUZKWmsrbFlLUGJDVzlqUU5p?= =?utf-8?B?SXdxSThNZHlJdSs5VTVDVXkzeU5jSHdmbitubU4rNjRkOTI3YmkrM0s1b3h1?= =?utf-8?B?ek1JUFExWWVGeHdWdW0wUy9pNU9TV1BtT3AxVCtIWkplQXRlYkZzS29UUkRi?= =?utf-8?B?aGFrNnZObFFscUFsVXl1U252OGlzdFpxOGR0cWZseHFUdDBzSWpJK25MVlZs?= =?utf-8?B?L2s3NDVCM0kwbXlGa3hNcXI1SGY4U1M1QktleXhOT1NJenhSRnozY1FJcmFN?= =?utf-8?B?a0N5MFMyaytTSG10WG9TaUozWjVZYmVmY3R0K2tlWTVGY2x2TENrcW8xV3BM?= =?utf-8?Q?K6SSm5PZxNFiOYUKQ3Hr8IXULhWSTA=3D?= x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SA1PR15MB5819.namprd15.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(366016)(10070799003)(38070700021);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?utf-8?B?aHdjU052dmNJVU9PL1dRek1LbENuNnI5alBvc0NmQ2h6MUxtMW5qS3UwOEZo?= =?utf-8?B?MHExM0c2VHlzZG1RS0Jzd1Z6b1pQSWFwaCtJTWYrQkFKY292MEpZQk5BTWEz?= =?utf-8?B?NjJVRURzZTRYVFUwQTVudUJIakNIUHEyU0dJVW9RUEJPcjhmV1FHRTV3UlJr?= =?utf-8?B?UmxVakxWdXRlaUloOUZYbXYzQWt1MEtSaVJHcHhOc2RCcHR6NFR5L3o1aFBl?= =?utf-8?B?MlNJZnRzZGNxMXhEa1BSZXY0UkFOSkpWUjJsbWVuUHRYUmtLTWRnU044MDVu?= =?utf-8?B?R2crNVBBcTBvRGJ5TDNUckNXVmZvMG9OWFlzQVg1WXJOQnVGbHhQZFVYTmg3?= =?utf-8?B?dmZZSlRlcnRmTHE4eENlMUJxcUM0VHlvU0tpSXFTRmFGSDBWU21KS2d4dEFz?= =?utf-8?B?bDJvUFh1SHNvc1k2V3lhSnc1dS9tdEpibU5zQ0RaSDdCMTJBVnkwdXJrWXpN?= =?utf-8?B?TUJtSjQ0OE9xSDhEOUx1RWRzUFYvNzJ0Zk1PTk1kaE5Hb1RDVCs5dXdBVGNa?= =?utf-8?B?UnJab1RLQ0UyeFIvQXc0bnhYMEFtMzM1aXdETEp3UTdnZk4xYTB4eVY4UUE1?= =?utf-8?B?L3VnQzBMaUVzVDFMcWx6NnVzN0FQd21RU1hwK3R4RlNNSjkzc2pXRkFKQ0Iz?= =?utf-8?B?bjE3MFZPUi9XV3BOT1FqU01wcTJadmRNa1o0SG5nSmFtNmFSNjVWc1FrNTM5?= =?utf-8?B?TTV2VkpxcVpNRHZILy9lOUpSRG02bzNZa0tSd1RUdytTaSs2bWI0dkpRMW5X?= =?utf-8?B?SDZCMytZRnBYM2hJRytzamhrSFBGQUlFZStybHN4QjZRa2lBRVNWL0hMVkRk?= =?utf-8?B?WlVCZ01FbklTM1ZkRUlsVW04MnRuZGpiYlhESkFTUnBldnB4eU5ocDMzNlRu?= =?utf-8?B?cndrM0VqMVBUd3c5enFXYWlWZXJyMGw1MVhmUWprUHB3L2NiOHV5ZU1RWlR6?= =?utf-8?B?ZGZHWmlVZXc0U3lSTHJsbnc3cVpaSnVhVnZWVUlFODRGVEREWWV4N0JnYmhB?= =?utf-8?B?VFVrRElORFJlSGtJSHZ1T1R1MUZrc2d5Y0UyUUI1aVp0a09oL0YvSkE3VVhp?= =?utf-8?B?SERUdGdBd05HZXd5QmpiYmJ6R3NqVGhRaWhxZmMwMk5Bdm43QXhzaDZDWnp6?= =?utf-8?B?U3F1Z0kzc0xCRXlkQm8rVlhNVmpCb0djSFVIcHVmUnVHY2dqaGNMS3VnVGJL?= =?utf-8?B?QlFRT0lhWVp4UXpPZFc4dENnN1BMMDVaUFFiM2JqcENjcGRObXpoN3RudS9u?= =?utf-8?B?QnE0YWZlbGdiQ1BqUjIwMUNBMzVuSXp1S04wUWVoYWc4MUhEc2hOcDBLUkc2?= =?utf-8?B?bUZ6UmxxNVBPRmhaR1hvT3hXZ09KbVJMNVQ3UHJUcEVEdENRNGx2Zlo2THN6?= =?utf-8?B?MkMvcWVPY1Y2bHYyRk1qWVpSRWI3ZURMQjh6MmdORllxdkVZSG5kOTZaVU9u?= =?utf-8?B?ei9SRFNzVU5ITHRld081eDZXcWNlMVNUNXlzNjdPU0FIQlN1Y1F3ZytQNzlr?= =?utf-8?B?dDlTb1ptckhOV2EzVm1LNnpJTnk3dTRRNkVKUWVGYlp4OCtrenRrQmV1aFdK?= =?utf-8?B?WnFUTERTZnRuNEF4eWZqNlJtQ2p4cHlSenBIKzZIZkN3TEEwblFHWURldm0v?= =?utf-8?B?WjVlY1lkYzhKb0JOVFhpQWVFVUU5d2JCVjg3WVYvRnhWeDRaVHhta05ERWdT?= =?utf-8?B?VE9oYzRnVHZpWmRKeFh5aXZHQ2xEazJFK0EwbWttNEN2SzFYWXZhMkxKOVZ2?= =?utf-8?B?VzV0QlR1S2l2RlZxRnJaT3Z3ZFF6bzU1RGxKblo4c1B3OXN0TzFQaEptNEVi?= =?utf-8?B?cmhXT01ZQ2hxdlRvc3RYUHIwYW41bDRlS3k5K3J0bGJUUHQyTTJuQUxBbEdQ?= =?utf-8?B?MEFKN2IwNFBTZW1kWEV0VGhtOGsxMGZVcXplUVh3RG5vOElLWDdEMTlwYkd1?= =?utf-8?B?MmpFRUVUbE9uSUUwL2JXNjl3TzQ1MUpDYnpLdllnQUZkcE9tMkI0Q1BUSDU0?= =?utf-8?B?WVJSWENKVFdKWmV5VSt6cFMvaXRMdUJKNWM1cktEK0daUHVESldwd1pVcHl5?= =?utf-8?B?Wk1zclBQazFDUkhoM01IeTg3Y1N5NnBmZm1BdTJRbngxMDFydjd6NGlwVlVm?= =?utf-8?B?K1RnZi91WHc2a2dHL2J1UTltK2hBZncyei9WdjlQNWxrQnBHMDhBZE94SHA3?= =?utf-8?Q?zcWv3Rs8l9b0FEpmBUfzCKc=3D?= X-OriginatorOrg: ibm.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR15MB5819.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 89e1cefc-c1d5-4254-3ee0-08ddf6de3782 X-MS-Exchange-CrossTenant-originalarrivaltime: 18 Sep 2025 18:07:23.0711 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: fcf67057-50c9-4ad4-98f3-ffca64add9e9 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: GYe2X3+4OTMkikI4BCIAM7Clx/9QVI1M3cLgmzzc5pcfZYLMqYmvCHcElzovAhAAGBpnzDaGIEDahnh1twxADQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY3PR15MB5057 X-Authority-Analysis: v=2.4 cv=MN5gmNZl c=1 sm=1 tr=0 ts=68cc4a5f cx=c_pps a=nAh4yJc8K/mwxcjpRfPwJQ==:117 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=IkcTkHD0fZMA:10 a=yJojWOMRYYMA:10 a=mDV3o1hIAAAA:8 a=pGLkceISAAAA:8 a=Z4Rwk6OoAAAA:8 a=zCXfdZZrKPHR1CA1UbsA:9 a=QEXdDO2ut3YA:10 a=HkZW87K1Qel5hWWM3VKY:22 X-Proofpoint-GUID: pWdvmxMlorKdfwVznW7vcDCZhf4RGirV X-Proofpoint-ORIG-GUID: Xr7z4W9BCRESXV1XLpoDrHgp6ucZftzg X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTE2MDIwNCBTYWx0ZWRfX4/OpZFHI7FNb j09ZaeZNdP7ykheOfT4VDbca9g27Kg7MILn4WazRCgE6brwZgYI2RGhb+fp2HKOgH8AB5xswsvv Vxmk8yiuSEZV8JE+Bh1JH3JYtjKUCPhT19lPZtDs4kF88r2+bg4lM81xVhutwssjGXgdHzvAUKH +7T3uv1UDxXTHZQx1aCFifixsgPZ4m2zKwZ8j0an0COvyc3EDY2eOFQ+XXRUFWwRNzBRDEFeJEm ddCjT3flDkiVD52Bh4mw9iFyIlopaNA28Ks5YPCruCQohYLGdZA4ulDnjO250t8Z16SqdIudPP2 fyiGeKdycSjgAPjrxsv6oiY6S/w1NTOJlIPxD6hfgZ2k3PtUTRgghNB96LAXOOLUfAqGu+ibQp+ eE4NKdZw Content-Type: text/plain; charset="utf-8" Content-ID: Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] ceph: Fix potential undefined behavior in crush_ln() with GCC 11.1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-18_02,2025-09-18_02,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 spamscore=0 priorityscore=1501 bulkscore=0 impostorscore=0 malwarescore=0 adultscore=0 phishscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509160204 On Thu, 2025-09-18 at 09:50 +0800, =E9=99=88=E5=8D=8E=E6=98=AD=EF=BC=88Lyic= an=EF=BC=89 wrote: > When compiled with GCC 11.1.0 and -march=3Dx86-64-v3 -O1 optimization fla= gs, > __builtin_clz() may generate BSR instructions without proper zero handlin= g. > The BSR instruction has undefined behavior when the source operand is zer= o, > which could occur when (x & 0x1FFFF) equals 0 in the crush_ln() function. >=20 > This issue is documented in GCC bug 101175: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101175 =20 >=20 > The problematic code path occurs in crush_ln() when: > - x is incremented from xin =20 > - (x & 0x18000) =3D=3D 0 (condition for the optimization) > - (x & 0x1FFFF) =3D=3D 0 (zero argument to __builtin_clz) >=20 > Testing with GCC 11.5.0 confirms that specific input values like 0x7FFFF,= =20 > 0x9FFFF, 0xBFFFF, 0xDFFFF, 0xFFFFF can trigger this condition, causing > __builtin_clz(0) to be called with undefined behavior. >=20 > Add a zero check before calling __builtin_clz() to ensure defined behavior > across all GCC versions and optimization levels. >=20 > Signed-off-by: Huazhao Chen > --- > net/ceph/crush/mapper.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) >=20 > diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c > index 1234567..abcdef0 100644 > --- a/net/ceph/crush/mapper.c > +++ b/net/ceph/crush/mapper.c > @@ -262,7 +262,8 @@ static __u64 crush_ln(unsigned int xin) > * do it in one step instead of iteratively > */ > if (!(x & 0x18000)) { > - int bits =3D __builtin_clz(x & 0x1FFFF) - 16; > + u32 masked =3D x & 0x1FFFF; > + int bits =3D masked ? __builtin_clz(masked) - 16 : 16; > x <<=3D bits; > iexpon =3D 15 - bits; > } Unfortunately, I am failing to apply the patch: git am ./20250918_lyican53_ceph_fix_potential_undefined_behavior_in_crush_ln_with_= gcc_1 1_1_0.mbx Applying: ceph: Fix potential undefined behavior in crush_ln() with GCC 11.= 1.0 error: corrupt patch at line 10 Patch failed at 0001 ceph: Fix potential undefined behavior in crush_ln() w= ith GCC 11.1.0 hint: Use 'git am --show-current-patch=3Ddiff' to see the failed patch hint: When you have resolved this problem, run "git am --continue". hint: If you prefer to skip this patch, run "git am --skip" instead. hint: To restore the original branch and stop patching, run "git am --abort= ". hint: Disable this message with "git config set advice.mergeConflict false" I am applying the patch on commit f83ec76bf285bea5727f478a68b894f5543ca76e: Author: Linus Torvalds Date: Sun Sep 14 14:21:14 2025 -0700 Linux 6.17-rc6 Which kernel version do you have? Thanks, Slava.