From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0D9C5D116EA for ; Sat, 29 Nov 2025 23:50:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5ADFF6B000A; Sat, 29 Nov 2025 18:50:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 55F1D6B000C; Sat, 29 Nov 2025 18:50:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3D7A96B000D; Sat, 29 Nov 2025 18:50:34 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 271156B000A for ; Sat, 29 Nov 2025 18:50:34 -0500 (EST) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id ABD041A0B70 for ; Sat, 29 Nov 2025 23:50:33 +0000 (UTC) X-FDA: 84165291546.23.AD5D8D1 Received: from AM0PR02CU008.outbound.protection.outlook.com (mail-westeuropeazon11013055.outbound.protection.outlook.com [52.101.72.55]) by imf02.hostedemail.com (Postfix) with ESMTP id 0E35F80004 for ; Sat, 29 Nov 2025 23:50:29 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=arm.com header.s=selector1 header.b=HibJGYmn; dkim=pass header.d=arm.com header.s=selector1 header.b=HibJGYmn; dmarc=pass (policy=none) header.from=arm.com; arc=pass ("microsoft.com:s=arcselector10001:i=2"); spf=pass (imf02.hostedemail.com: domain of YeoReum.Yun@arm.com designates 52.101.72.55 as permitted sender) smtp.mailfrom=YeoReum.Yun@arm.com ARC-Seal: i=3; s=arc-20220608; d=hostedemail.com; t=1764460230; a=rsa-sha256; cv=pass; b=z2SIEUcJFo9UNUWxNPWEJW22G8zCwJKLOrbNmRjk6fGllZKN8im4QTU7P241MvY5U3GBnw FTpfiyWiLKGBCnUvc4Z4QGKspS6UCx/vmUblwNJsmKQ4uyuVsEqd1vAvCBeTXOgA/ra96w Rc2SCkUTSXKJFx4QpQPrfOwuP7fr0iY= ARC-Authentication-Results: i=3; imf02.hostedemail.com; dkim=pass header.d=arm.com header.s=selector1 header.b=HibJGYmn; dkim=pass header.d=arm.com header.s=selector1 header.b=HibJGYmn; dmarc=pass (policy=none) header.from=arm.com; arc=pass ("microsoft.com:s=arcselector10001:i=2"); spf=pass (imf02.hostedemail.com: domain of YeoReum.Yun@arm.com designates 52.101.72.55 as permitted sender) smtp.mailfrom=YeoReum.Yun@arm.com ARC-Message-Signature: i=3; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1764460230; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=o/AAG4J7hGv6Xqju4De+6WZ7MuhVaW5m5azDyDR/Gq0=; b=cO+aFmfF+dXIRtqRkdxEjAdd7tvDTXJwLN0STsn56OPfBfHVibAaljoQamCH92I2/NqD33 8QJIPnKMyNJ1y4O/IfntdZ3gS4eQFdXj8/+B1nb/F5zZC/hiMgQSt3P5uTN++fQMen+ZxO WKcL1rBIIU22XhQWiUPbSAawBBhDw3o= ARC-Seal: i=2; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=pass; b=G3CePrCdPcFbgfcOO4MBQy04ePx4x2DhFI/YOLJRKVaQdT5d9+lX/Sn06SAOb+B1Wt3PTUq5I1NyoOldYk87b/zwWlQZDtXIV7T1r+Dm4NRnMYWSTPqtUDaOUz/q87dSboYZMi392xQfjoHOV79IN66j/QsiBAHRnfYSgeoGLE2GWHk6iDtNoWjFDLXz4smffjx5vVGfIoP/X9jbaUAan+cICBHg8TrlqlqHWOhwGzEAIEQ6lXDcu666SkcAIh3u55EiUVK/r/A+bF3dDYXIQVmOLhg3WXPPEwDaH692hZmZHY81991+KWkTWW/0h2NBlobXgqAl2GtdD5e7oobSGA== ARC-Message-Signature: i=2; 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=o/AAG4J7hGv6Xqju4De+6WZ7MuhVaW5m5azDyDR/Gq0=; b=wKmiUkEJNPJvVpak8uCKu4CJxKVrzK5zJGGfJPRIgI67+UeoYGfI60wFfva3Ht6JEfTwcgXAraQ2/rNBeKBBC5KBNZfISVVNNBA1XUtYHAn2mpfLM/zJn7CFZR//qQ/zQ/XDExrXLssW1fBwEHn0gwBkwuF5F+KRH67hNJAy3wsPgoMQu6zfWMriB3VFc+IrKw23BZclXEDPNRCOvU92QIZQn+QrvI7AFsdjCDidMc8l/1oKey/XdPMAVgIV1W0jpQlIYJX4TXESej28nzryZpVC2Y13ll6Vw1cXs/ZLh0rf2qSmSb/QX+IVdyGWKsaDD22xp9jrEqugIvozvBaZlw== ARC-Authentication-Results: i=2; mx.microsoft.com 1; spf=pass (sender ip is 4.158.2.129) smtp.rcpttodomain=linux-foundation.org smtp.mailfrom=arm.com; dmarc=pass (p=none sp=none pct=100) action=none header.from=arm.com; dkim=pass (signature was verified) header.d=arm.com; arc=pass (0 oda=1 ltdi=1 spf=[1,1,smtp.mailfrom=arm.com] dkim=[1,1,header.d=arm.com] dmarc=[1,1,header.from=arm.com]) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arm.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=o/AAG4J7hGv6Xqju4De+6WZ7MuhVaW5m5azDyDR/Gq0=; b=HibJGYmnBDNyGu1sKzpNXAAR0g1KCqyt8dXv3UJvCoATO7vb2EOZ+SRrVAh+53DK02OGhxxJFJnxNuJ91+8XT2290Om6rBMLlh+0yS0+cQ1eKhdL9o5O7HsEvB1uzQh6AhE6UrE1GkS7D4LZ0nW/ZV/aKGgKPjGb5IGYPzOqkTI= Received: from DUZP191CA0069.EURP191.PROD.OUTLOOK.COM (2603:10a6:10:4fa::22) by DB8PR08MB5418.eurprd08.prod.outlook.com (2603:10a6:10:116::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9366.17; Sat, 29 Nov 2025 23:50:24 +0000 Received: from DB1PEPF00039232.eurprd03.prod.outlook.com (2603:10a6:10:4fa:cafe::76) by DUZP191CA0069.outlook.office365.com (2603:10a6:10:4fa::22) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9366.17 via Frontend Transport; Sat, 29 Nov 2025 23:50:22 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 4.158.2.129) smtp.mailfrom=arm.com; dkim=pass (signature was verified) header.d=arm.com;dmarc=pass action=none header.from=arm.com; Received-SPF: Pass (protection.outlook.com: domain of arm.com designates 4.158.2.129 as permitted sender) receiver=protection.outlook.com; client-ip=4.158.2.129; helo=outbound-uk1.az.dlp.m.darktrace.com; pr=C Received: from outbound-uk1.az.dlp.m.darktrace.com (4.158.2.129) by DB1PEPF00039232.mail.protection.outlook.com (10.167.8.105) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9388.8 via Frontend Transport; Sat, 29 Nov 2025 23:50:23 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=RP8Rw27o+MN9VsOcvyQzBsiJ2wmvLapZ7qG33jY08UDzyWycjlyppRs+5ByXcicRLIh4sPx5eouWf2O0DtvxyNzzAIM2niGpiQcuO7Tr1pD4c3f8B3t3jRixlDIvfwW4od7JJEzS+YShqBX1rvlwVCvIUWlh4ct6zMpDInn1S2zcH4VB91XyOtnO+eljuQbgp8ePNkIFNifaHVL6tNjRp/WMRLBuagsFNmFpxdMq3hPN+WloiooxLGA1NLXcybl+vTyibEZcvYkWmrit3pbbwJ2GmsN88mlcTQczhsKnt+mwSWAeaFmEsdQBvkYlJpg6GkH+dc2rGzvlcaixfipwhA== 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=o/AAG4J7hGv6Xqju4De+6WZ7MuhVaW5m5azDyDR/Gq0=; b=LmPB7ShfXTGx33Z470taY96xLcS6QcOHO9EYqulFm+cMC/3wmpWOzxYihN7Ai3RtH7YxeAeYvqIv8jmIp5FBE8JCtjGRg9foffncXdITL/6kapAvpB4cZXp6qGl2k+OcVWb5Rm4JFM1Yyoz8vP115GX/agrviI5pnNoqHu35FpPUpnf8l2yhwNPTIuj6BWEy4hFnxOCHLgTajkqAQXI5NuYM2RIMOh/pBHgbO3S6Mli6S0nRDiFRln/dt+Ud9Ji+1YHbwL0UcX5C92bEfkc/9JUkn4ExNIraQMmqAvT6lacqgATx1Vjk7BVWnO5oWuAItvhd3GHvaMQRVrszZbpuEg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=arm.com; dmarc=pass action=none header.from=arm.com; dkim=pass header.d=arm.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arm.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=o/AAG4J7hGv6Xqju4De+6WZ7MuhVaW5m5azDyDR/Gq0=; b=HibJGYmnBDNyGu1sKzpNXAAR0g1KCqyt8dXv3UJvCoATO7vb2EOZ+SRrVAh+53DK02OGhxxJFJnxNuJ91+8XT2290Om6rBMLlh+0yS0+cQ1eKhdL9o5O7HsEvB1uzQh6AhE6UrE1GkS7D4LZ0nW/ZV/aKGgKPjGb5IGYPzOqkTI= Authentication-Results-Original: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=arm.com; Received: from GV1PR08MB10521.eurprd08.prod.outlook.com (2603:10a6:150:163::20) by GV2PR08MB8342.eurprd08.prod.outlook.com (2603:10a6:150:bf::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9366.17; Sat, 29 Nov 2025 23:49:17 +0000 Received: from GV1PR08MB10521.eurprd08.prod.outlook.com ([fe80::d430:4ef9:b30b:c739]) by GV1PR08MB10521.eurprd08.prod.outlook.com ([fe80::d430:4ef9:b30b:c739%3]) with mapi id 15.20.9366.012; Sat, 29 Nov 2025 23:49:17 +0000 Date: Sat, 29 Nov 2025 23:49:14 +0000 From: Yeoreum Yun To: Andrew Morton Cc: catalin.marinas@arm.com, kevin.brodsky@arm.com, ryabinin.a.a@gmail.com, glider@google.com, andreyknvl@gmail.com, dvyukov@google.com, vincenzo.frascino@arm.com, urezki@gmail.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, stable@vger.kernel.org, Jiayuan Chen Subject: Re: [PATCH] kasan: hw_tags: fix a false positive case of vrealloc in alloced size Message-ID: References: <20251129123648.1785982-1-yeoreum.yun@arm.com> <20251129100658.6b25799da5ace00c3a6d0f42@linux-foundation.org> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: LO6P123CA0003.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:338::8) To GV1PR08MB10521.eurprd08.prod.outlook.com (2603:10a6:150:163::20) MIME-Version: 1.0 X-MS-TrafficTypeDiagnostic: GV1PR08MB10521:EE_|GV2PR08MB8342:EE_|DB1PEPF00039232:EE_|DB8PR08MB5418:EE_ X-MS-Office365-Filtering-Correlation-Id: d6acc3a6-a16a-44fb-7f43-08de2fa2101d x-checkrecipientrouted: true NoDisclaimer: true X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0;ARA:13230040|1800799024|376014|7416014|366016; X-Microsoft-Antispam-Message-Info-Original: =?utf-8?B?MlRHS2JOYUR4MmdQT0YvdkhSR0hObEdFU2dmOHhYRFl1RUROT1pBdDYvTEdk?= =?utf-8?B?V0lGWnJBSXFCYUFaTDdJMjBqYlJOUFR3d2NwTkRUNXRnYkVlRUM5SnZzQ2tq?= =?utf-8?B?QnYxU0I2YXVPMFpmMkVvcHBnK0E3bFJCbG1jSXJyUmtRVFFUWFZweHVCNWNI?= =?utf-8?B?ZG1uWUtHeXBWamxQWExkem9mc2VaWWxFdG1YbGFGdmFnbVF6c2IzNzgwUm9F?= =?utf-8?B?UGY2RHdPb1BubHRqRGRjY0lpK0dnT1NHRGpQc3JwYm9HZFZNM1ExRTVUQXcz?= =?utf-8?B?a2thNHY4KzJNVFQ2S2lCNzVIUnh3MHBWNGQzY25tSUI2MytGMHhlZmxrS21m?= =?utf-8?B?T1ZneW5BaDEwdWZMVk1CQ2JCdnhwQ1dBdC9jT2NKaGhQN1RqVFpWeEZYWUM0?= =?utf-8?B?bzE5UkFlbnFqU2U3Uy9yb09Rd1BNVStwZ2VqUDRQQUo4dTVmSWlYR1lPS1ZF?= =?utf-8?B?ZXRSVnVrenVMcTBieWdXc3AwVElWWnNUS0FSSDI1bkhzWmlDRVlkbDhDWXVu?= =?utf-8?B?djBsa3N2WWw2UWVSaUtGL3VXZzBWMS9GaVhrNTQya2tNb2dJbTVBVW9zWFVT?= =?utf-8?B?eW0yM3hwRnljMnNXL2p1UnVXNkE2c3RVU3NVTDU3R1lyUUJIV3RzQS9Iayt3?= =?utf-8?B?R2tqSUhVMEVSdG8zNTg2a3lKODAwemNaWG8xa2dDMFVNbWUvQ09RYy9jS1B2?= =?utf-8?B?ZWN2alh0MU1nZ28reXV2a0VVc2VHcVdPK0ZDWHo5N0xCWHg0WUV0SlBZTERh?= =?utf-8?B?OWV3cEZ1OTI0QlNRelB6aU12ZUhBOVNzSjVaZmVNeS8rWjhEeXJiKzhaZEIx?= =?utf-8?B?T3VGZ0lxbUpDWXkxOUhyL3lzbElZRWc5MVRxN0U1amQ2WThkVHFyd3czc1hO?= =?utf-8?B?ckdUNlEwWDQxdmM3a1IxR3hURC9jZlNWTXUrYWdUREZJWUlRaFZ5NUhVK29S?= =?utf-8?B?enpCOU45bTdYZnozT0FnRGkweExPemswcFlacjRTa3lLWUxNaE9rcGdEalpU?= =?utf-8?B?OHo0Z29uV0djSlJZL2JEMXR5ZFVpbFJxaUtKbkk5N2R2M3RkZ2dSYi9PVkd0?= =?utf-8?B?anVrc2ExdFN6M3V4OXpEV3VMY3VxcC9GS0VwcWNRV3YzMEFjWkhxT1FVQ3FM?= =?utf-8?B?dnJFT1pHd0pyMVB0RUNOUGNrUVIwbG12VUJWYnpra251Z3BzeDAvei90SVBO?= =?utf-8?B?UFc2OE52S1dFMFBNWlU5Z1ltdjJwdFpNVWI1Y0Z1cDlpQUdtaU9VUVFudTRk?= =?utf-8?B?aFNFbnUySG1zU1grb1AzTmdWcC9zakpzSU81UDlId25MWHBFMHgyeWhFOU56?= =?utf-8?B?TmlaQWtoWnBDNTlHUTE5bVFNSFQvMTEvUEFyazVOd1UzeEp6NElNcW9jN2gy?= =?utf-8?B?TnJxVjU0bHF5b2R5RWd2ellpcDV1azg5eEVCY0RRV1NOZjNESFJWY3FYLzBz?= =?utf-8?B?VGhDNUcvR24zMlFmM2dnZHF0ZkFYZVNVY2R6WjlCQXA2SXlIcENFUGMrL2RR?= =?utf-8?B?c3FTaXk2bWlQTDNRVU9ISTVFeHR1YmQwclNpaXdBK29vQVYzSDFjS0pka1Y4?= =?utf-8?B?N1kxUWhSSHZZdmRHWmY1MWxnalQ1ZFZMV3VIR2h6RVZ3M3pZWXlhOE5wSDhD?= =?utf-8?B?dTdNbUVZZVM2N1A3NExOdzA2WTI2N0V4S3ROUW4yTS9yNjhzSFBjMXFrNEth?= =?utf-8?B?Y2ZZRVhJdDJTY1Y4Mlpncjh2cGJnNVFQSVA5cHhqa0pkVXBCUCtOS1U0R3hX?= =?utf-8?B?ZFBJajlLVjRSUVZoczJMdXRHNlR6ZytnbVFoT2l1MWt3Tmh0VUNXNFl3T2tP?= =?utf-8?B?Vk11bk8zTmowSW5uTHZ3YXgydk9LNEJMV24rbmdIZUg0UWloaXdiNmdHT0FJ?= =?utf-8?B?cHVNNUJKOHJxS3V5SzRoQkUvMmxJQWY2TmdFalJUQ3kyVmhKTmthUlR5eEQ2?= =?utf-8?B?eEVINXRzZ3Y0UWNOaWJldlZjUzQ4WHVFNlBXeTFLTkZ0Rkc1OUw4TEhWMHFO?= =?utf-8?B?Y0FEREdCWStRPT0=?= X-Forefront-Antispam-Report-Untrusted: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:GV1PR08MB10521.eurprd08.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(7416014)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV2PR08MB8342 X-EOPAttributedMessage: 0 X-MS-Exchange-Transport-CrossTenantHeadersStripped: DB1PEPF00039232.eurprd03.prod.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: 6179f722-8757-4981-9f41-08de2fa1e878 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700013|14060799003|376014|1800799024|35042699022|7416014|82310400026|13003099007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?aEhNczlRcmJBR1RHMncxem1xMHNGeXZFUUUvbnNpWEZEd0JveEt2WEFWU2wz?= =?utf-8?B?WG4wQ01rMHRBeU1oSDluZFY2U3dQOHE0SUtZSUtncTdMcFJLa0dXaURNcU0x?= =?utf-8?B?U0NDbkRhQkpJOXpkR3hIZXNqR2VLQUtFMWY1MmtwQ2RFUWJVSnh5aVQ2V0xJ?= =?utf-8?B?Y3Z1Mzg1bnpwdHdHWUw2MnFYOHRVZHRpMWgrMWxMSlRubVZ5YzJKdFI5eVdW?= =?utf-8?B?MDRTajkwVk5MTG9qWmJHai8xeVJyR2RGSlg5WVp6Z0VRSExFd0tIanhyU2ZB?= =?utf-8?B?VlU4Z2hTZDV4RDI2NHRrRTVpdzB4L2hTYXlPYW0wTzFsVUNWOGIwdjFaUXV5?= =?utf-8?B?VXhZblh1VUJzTzI4MDlwRFc0eEhubndValhGNk5jeGcyakNVT1A2bDJxV1Iw?= =?utf-8?B?eU9HZ0h0UmZSeHVDTlVPZkdEL3ZrNDRkZHpLeVlaV0phcDZKekoxSm9tSWNP?= =?utf-8?B?c1YveXdMMnZZd3dpbUZxMHNzRGk0b21aTGJQVEtOM0ZMTklZZ1N0WXFoK01F?= =?utf-8?B?cm1OVnhZcjFyN0wvd2RKUE9rRUZHcE5OdzArZjdCNWRlSTdqUHJJSm9ZaEJP?= =?utf-8?B?Nlo4R3JXZFFMM283bEkvdkJiOUx5QWhpejBSSDkzUE5TWmtvRVpERzdiZTBu?= =?utf-8?B?WTVSbENyZVRtemhqWjJrRlFlWkd6WkRxNGQxNjZKeWV2cUl6QUxBc3lhak5m?= =?utf-8?B?dUVtM00vZEo2RCtldys5Q2duK2pJenZ1SHRDU1kvV1FWSGdRc2NQR3dlaGxC?= =?utf-8?B?Tmg4K0xhOXh6dFhJTGZRcGtPS1RzaFl1OHU1RDV5WkQ1OXN5N1BGZzYxemJH?= =?utf-8?B?VEtIQnA5TjlKdE1KVUxLclFuWGVxSm80Ri91WTBxRSt0dTB6RlFJWFdXNEI2?= =?utf-8?B?WDg2UzZmbW41aWhEd08zdm1UTkVYQzZQNElwSVY5VHhhZnFaVy8zTDd5aVRr?= =?utf-8?B?dkpjTGliNjZ3bVYwMlFFci9uTFY0RlJrQlR6Sk0vdlNnZkMyWWtiYUNLcGpk?= =?utf-8?B?ZC9qQ1FjbU1aekxNZ2xjQ0hkeU4xZ1BhWllpMmlaVVA2VEZJTk1BOFYzRTFH?= =?utf-8?B?Q0VmbG9jQUlybWo1T3M0Y2hRcUFTVnVUdm5mUmpmZ0tNMDJzR0xWb2ZOQ083?= =?utf-8?B?WnVIY295SU52VHAwclVjVjhHQllPV3V0enBZOFhabVhlOW00SGpVa1pDRUtZ?= =?utf-8?B?OUhEOU5CTE1VTXU2bXVEMUY5QTVOajQxeGV3QVQzSnMrZFhXQ0FmSWg1RXcy?= =?utf-8?B?UXgxWGxuaEpZbFl3WjdSV25wcTk0N1lRWi9mamZ0eVJQbzZCVEI4SVZkZ2Zw?= =?utf-8?B?VUdWTkZUOTE2c2MwQlF0Z294aFlsbmpQL1JXZ0lNSGF3UUppZzJKZ3c4c0dZ?= =?utf-8?B?U05Wemh2b1dWUXc1RnlnMHRLckFCQnI2bEZRQzZFTzdrbkorZld6T0NpTXoz?= =?utf-8?B?MlNUNDFSc2N4OTV3ZjlNdVdCbUdybkZmT3ZEcGcwbmV5NVY1ZlQzT0tINmpY?= =?utf-8?B?RDZGWjR0MEFsNHdGSEtmK3YzSTBhcmFzbjhxVExFVksxRHhaOGxjaCtwb3B3?= =?utf-8?B?TXRtRlhmTDdyWEpvdEYyaE44bk1JcmkxTXFta0lqaGRXLzRKQ3EybTFmZm9k?= =?utf-8?B?YWorK3d5WWI3OTlNY2NqVGRTL1B5a3lCYmJCeUs4SEU3WEptQ0xRS24zUUZY?= =?utf-8?B?RzdZQXl3Y2lDSXFtbGFORlBydmpZdGpsZmdDTFR6QXN0cCtpU2R1YU5UVmVZ?= =?utf-8?B?a2R6SThoTEFvU2xHNTdVbzB3M2loeFhQaTlJTCs3cG5iUzJSOWw1L0w3SnUw?= =?utf-8?B?UTA2N0hLZDkxK0lRdElCc0FzUVRweHhvUVN1WXNPUjdZMW9yaG1NaE9Kelgr?= =?utf-8?B?UnBNbjc4ci91eC9NYnMxM3B6cXhtTWpIdS9FQWExS0taQ05PNlZWeVhPM255?= =?utf-8?B?UVFoZzdyQ2JObjl2UG5XTnd2NTdTT0g4VG4rbTErMzMrSW1vMnFqVDltczRE?= =?utf-8?B?WXdDdmZ3MjByZUQ0Z0ExRWN5bEw5VjVjSFZzYVNBUmtzRlg1a0g4NTdGa0Z1?= =?utf-8?B?WmF1RGdMUmpST2lmckpyU3Q5NE5rdGNINmNDRjJTV0FYVU1qVmhOaTBDRGpD?= =?utf-8?Q?yExM=3D?= X-Forefront-Antispam-Report: CIP:4.158.2.129;CTRY:GB;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:outbound-uk1.az.dlp.m.darktrace.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(36860700013)(14060799003)(376014)(1800799024)(35042699022)(7416014)(82310400026)(13003099007);DIR:OUT;SFP:1101; X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Nov 2025 23:50:23.3690 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: d6acc3a6-a16a-44fb-7f43-08de2fa2101d X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[4.158.2.129];Helo=[outbound-uk1.az.dlp.m.darktrace.com] X-MS-Exchange-CrossTenant-AuthSource: DB1PEPF00039232.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB8PR08MB5418 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 0E35F80004 X-Stat-Signature: bffu53oujtg7igdoucd6ymerjjaxwp3p X-Rspam-User: X-HE-Tag: 1764460229-941181 X-HE-Meta: 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 CHXiLBKB 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Nov 29, 2025 at 11:26:25PM +0000, Yeoreum Yun wrote: > Hi Andrew, > > > On Sat, 29 Nov 2025 12:36:47 +0000 Yeoreum Yun wrote: > > > > > When a memory region is allocated with vmalloc() and later expanded with > > > vrealloc() — while still within the originally allocated size — > > > KASAN may report a false positive because > > > it does not update the tags for the newly expanded portion of the memory. > > > > > > A typical example of this pattern occurs in the BPF verifier, > > > and the following is a related false positive report: > > > > > > [ 2206.486476] ================================================================== > > > [ 2206.486509] BUG: KASAN: invalid-access in __memcpy+0xc/0x30 > > > [ 2206.486607] Write at addr f5ff800083765270 by task test_progs/205 > > > [ 2206.486664] Pointer tag: [f5], memory tag: [fe] > > > [ 2206.486703] > > > [ 2206.486745] CPU: 4 UID: 0 PID: 205 Comm: test_progs Tainted: G OE 6.18.0-rc7+ #145 PREEMPT(full) > > > [ 2206.486861] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE > > > [ 2206.486897] Hardware name: , BIOS > > > [ 2206.486932] Call trace: > > > [ 2206.486961] show_stack+0x24/0x40 (C) > > > [ 2206.487071] __dump_stack+0x28/0x48 > > > [ 2206.487182] dump_stack_lvl+0x7c/0xb0 > > > [ 2206.487293] print_address_description+0x80/0x270 > > > [ 2206.487403] print_report+0x94/0x100 > > > [ 2206.487505] kasan_report+0xd8/0x150 > > > [ 2206.487606] __do_kernel_fault+0x64/0x268 > > > [ 2206.487717] do_bad_area+0x38/0x110 > > > [ 2206.487820] do_tag_check_fault+0x38/0x60 > > > [ 2206.487936] do_mem_abort+0x48/0xc8 > > > [ 2206.488042] el1_abort+0x40/0x70 > > > [ 2206.488127] el1h_64_sync_handler+0x50/0x118 > > > [ 2206.488217] el1h_64_sync+0xa4/0xa8 > > > [ 2206.488303] __memcpy+0xc/0x30 (P) > > > [ 2206.488412] do_misc_fixups+0x4f8/0x1950 > > > [ 2206.488528] bpf_check+0x31c/0x840 > > > [ 2206.488638] bpf_prog_load+0x58c/0x658 > > > [ 2206.488737] __sys_bpf+0x364/0x488 > > > [ 2206.488833] __arm64_sys_bpf+0x30/0x58 > > > [ 2206.488920] invoke_syscall+0x68/0xe8 > > > [ 2206.489033] el0_svc_common+0xb0/0xf8 > > > [ 2206.489143] do_el0_svc+0x28/0x48 > > > [ 2206.489249] el0_svc+0x40/0xe8 > > > [ 2206.489337] el0t_64_sync_handler+0x84/0x140 > > > [ 2206.489427] el0t_64_sync+0x1bc/0x1c0 > > > > > > Here, 0xf5ff800083765000 is vmalloc()ed address for > > > env->insn_aux_data with the size of 0x268. > > > While this region is expanded size by 0x478 and initialise > > > increased region to apply patched instructions, > > > a false positive is triggered at the address 0xf5ff800083765270 > > > because __kasan_unpoison_vmalloc() with KASAN_VMALLOC_PROT_NORMAL flag only > > > doesn't update the tag on increaed region. > > > > > > To address this, introduces KASAN_VMALLOC_EXPAND flag which > > > is used to expand vmalloc()ed memory in range of real allocated size > > > to update tag for increased region. > > > > Thanks. > > > > > Fixes: 23689e91fb22 ("kasan, vmalloc: add vmalloc tagging for HW_TAGS”) > > > Cc: > > > > Unfortunately this is changing the same code as "mm/kasan: fix > > incorrect unpoisoning in vrealloc for KASAN", > > (https://lkml.kernel.org/r/20251128111516.244497-1-jiayuan.chen@linux.dev) > > which is also cc:stable. > > > > So could you please take a look at the code in mm.git's > > mm-hotfixes-unstable branch > > (git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm) and base the > > fix upon that? This way everything should merge and backport nicely. > > Thanks for sharing this :) > But I think the patch from Jiayuan still has a problem > since vrealloc() can pass the "unaligned address" with KASAN_GRANULE_SIZE > and this will trigger WARN_ON() in kasan_unpoison(). Ah, I missed his patch change the pointer from p + old_size to p for the kasan_unpoison_vrealloc(). Then the patch seems almost identical to fix the same problem. So, you can drop my patch. Sorry to make noise :\ [...] -- Sincerely, Yeoreum Yun