From nobody Thu May 1 13:13:30 2025 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4ZpDyf3169z5v91F for ; Thu, 01 May 2025 13:13:46 +0000 (UTC) (envelope-from mibelanger@qnx.com) Received: from smtp-p02.blackberry.com (smtp-p02.blackberry.com [208.65.78.89]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4ZpDyc2H3yz3C29 for ; Thu, 01 May 2025 13:13:44 +0000 (UTC) (envelope-from mibelanger@qnx.com) Authentication-Results: mx1.freebsd.org; dkim=pass header.d=qnx.com header.s=pfpt20241003 header.b=42+wA8lm; dkim=fail ("body hash did not verify") header.d=blackberryltd.onmicrosoft.com header.s=selector2-blackberryltd-onmicrosoft-com header.b=r5+Ve+Pw; spf=pass (mx1.freebsd.org: domain of mibelanger@qnx.com designates 208.65.78.89 as permitted sender) smtp.mailfrom=mibelanger@qnx.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); dmarc=pass (policy=none) header.from=qnx.com Received: from pps.filterd (mhs403ykf.rim.net [127.0.0.1]) by mhs403ykf.rim.net (8.18.1.2/8.18.1.2) with ESMTP id 5418El4L010174 for ; Thu, 1 May 2025 09:13:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qnx.com; h=content-type : date : from : message-id : mime-version : subject : to; s=pfpt20241003; bh=9+fCy6ql+vMQ9vvLOy3tjzBgaMrt8SsIbJBlJ7UMx7Y=; b=42+wA8lmwyn8hNQPWHFnAKN6x+Jj6+m3LrvUryVItTvIKapJ7kk8q/YO2tKpoK9YN8Er QLzIkldxfnns/2siGQm8bKWpbRNxLUlFar6tYF9wckPplnOvcPj9eDIBV5Ufjp5dfLDI pYvd7ZNpv+ukrC+itkHErO6ivf22b55qxzrvlCHazTf+hcSjotVx757xxNP4Jv+2R6UA xLfZJyDOrBSemNF5FDLry/UQMaK+lnhgLTdytjTugntbFl8oIqUsES3TAxu2INPncFK4 ttWnqvW4RUhOvQVQoFNFS0j3adD8moMuUPgm3YDSZoZVFsuO2wP16EaTfyJy0JXs5KGX Pg== Received: from xch211cnc.rim.net (xch211cnc.rim.net [10.3.27.116]) by mhs403ykf.rim.net (PPS) with ESMTPS id 46b7urrxnj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 01 May 2025 09:13:38 -0400 Received: from XCH211YKF.rim.net (10.12.114.211) by XCH211CNC.rim.net (10.3.27.116) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.34; Thu, 1 May 2025 09:13:37 -0400 Received: from xce211cnc.rim.net (10.4.225.59) by XCH211YKF.rim.net (10.12.114.211) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.34 via Frontend Transport; Thu, 1 May 2025 09:13:37 -0400 Received: from YT5PR01CU002.outbound.protection.outlook.com (40.93.18.48) by hybrid-smtp.blackberry.com (10.4.225.59) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.44; Thu, 1 May 2025 09:13:37 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=kbv9k7ZzmU1AAPrhY0mxogYv25uixKbuUU/eK9O8nLcQSG3DxpgSUyV8xzAT0buyYhroLyLHfSL0kiZ57oOQ/YXnE2hMpk+B4NSSC48XL/wIJmCytl2IL8K4SgOdDNcYTU02EHqxVPzfKts6FcNDFYWwpv474Xbh3WA9VTU3VgK6c6v+aH3NH6e+JvG4p6y86SMHe4G/XQUwNR/tDXAM1OgPxh3uTLr24Q7WrBKidNgjXAipDjQv7UxNCDFcX05inb1PZAEIjjLnomp1Njr7dwGmLcFyipm+SKpFyS3IiDgGTHWJ+s8O5vhu6IzKxqzEvpXD4gswqyhK5UMsfa2RFQ== 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=MaCB7xgRDUtSPWmmd8Sc+OtbBHdcqz+8Sd9h1idfDVo=; b=GQuSRystGmyBQtkQHZC/xKkDB9tK9hOoud/PEzEy3sp/9dqUb0TgtTxw1ExUmRjitEr6Q5dAufNOpT+NKicXVpBLwe5Um/LOEJY9FC+PuzWcPAvf34ofHkCJt5g5RfACbS+gWe3HADlC1IEsO432co44KfH3us98pnKSp+61K0nlp0G55rsVBVxyr02olekL36hYUnsy5WoKNn3W7x69n2AwtFCvl8mmrNkXrYvGSWbfkvjsE4Ijb568r1cvxJdsnG/xcf/qeXsNLpjFAlr/fcEMDcP2NW58HjJWGO3HrtczMfGwQLEn/a4D0Qi+5K5A4aiTfg/gXhcy9mCx4dH3kQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=qnx.com; dmarc=pass action=none header.from=qnx.com; dkim=pass header.d=qnx.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blackberryltd.onmicrosoft.com; s=selector2-blackberryltd-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=MaCB7xgRDUtSPWmmd8Sc+OtbBHdcqz+8Sd9h1idfDVo=; b=r5+Ve+PwoJknB/GV/Tiv4RPiq9Hjo+PpgOaSoacBfR1dGyjH29mjkOD2lzHMOi6ztpDTAsqnVDF1BHBgzrZ1fKBNp4jVVk/xZvcaYpv4pIUV8m+4Dy2VSyl/fybhVfkpWC6jOrCKknutZI4RzqyHyVFUM02ZGYt3qx/LWBtxxQU= Received: from YQXPR01MB4198.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c01:11::8) by YT3PR01MB9314.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:a3::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8678.37; Thu, 1 May 2025 13:13:30 +0000 Received: from YQXPR01MB4198.CANPRD01.PROD.OUTLOOK.COM ([fe80::3789:7f3:7258:6f2a]) by YQXPR01MB4198.CANPRD01.PROD.OUTLOOK.COM ([fe80::3789:7f3:7258:6f2a%5]) with mapi id 15.20.8699.019; Thu, 1 May 2025 13:13:30 +0000 From: Mike Belanger To: "freebsd-net@freebsd.org" Subject: Race condition in ether_ifattach Thread-Topic: Race condition in ether_ifattach Thread-Index: AQHbupkrIaz/VXqEZU28rZfpENLFaA== Date: Thu, 1 May 2025 13:13:30 +0000 Message-ID: Accept-Language: en-US Content-Language: en-CA X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-reactions: allow x-ms-publictraffictype: Email x-ms-traffictypediagnostic: YQXPR01MB4198:EE_|YT3PR01MB9314:EE_ x-ms-office365-filtering-correlation-id: 540831ef-e7e1-4e08-d9ea-08dd88b1f7a9 x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0;ARA:13230040|1800799024|366016|376014|38070700018|8096899003; x-microsoft-antispam-message-info: =?Windows-1252?Q?aQV1c+raf0CWA0EXUFKEBej9aD46m6VNnupoGcx25oNCcFQaJXbZDaVg?= =?Windows-1252?Q?fF/UNMNKGaCFrMcKwBpjzcfr2tebZqGfeZRKgyqDsqitH8/6AAGQ3hhL?= =?Windows-1252?Q?wYbh1CtxyRt5dvPEDscm7+5BfMTIdOk+OiyTnTuEA8jAhWOh2GJUc0Rp?= =?Windows-1252?Q?/LaZ5uz1KjPad65Fw5GKQCorqwTzVq7tDY6isZEKRbj0Lg/0R8c6RCIC?= =?Windows-1252?Q?IBGWBaxPbRPp+cx+YtR7o2jAIdEMXX+fndYcwU5EuwyO4GsYzUaz3yFr?= =?Windows-1252?Q?QFB+2k9XJJAgsS6hMEJCP3vyMUYJI8P3yy1le9WKbw0JTNuaX8/7qgrc?= =?Windows-1252?Q?mpumcvmxhvuvYetgR37QyF6oVMPSWVUgO2j1+u11UaMF7apRcpterI0b?= =?Windows-1252?Q?NL7Xr6zvNhKgPXeoM46aOGTk95grhm8E/u3cdo/5L0w6T7TLU+FeBdkO?= =?Windows-1252?Q?nPJwezoyHYThp8vJdBTc7oiIbjddnRmz8ACfvnMc/3mPiJAscGYzWZZT?= =?Windows-1252?Q?cirmRjd25K0usV7uAX0qs7xyjNmFOsgd2e3bfb771o9/oTVYUgdp7l++?= =?Windows-1252?Q?e4g2M8U17C47Kr6mG1Vm+SEZuZtKAQS4njyx4ScIejBP4EndKmzMSJjd?= =?Windows-1252?Q?BYQU+FYyTdCKYUe8FkyySMrOaQjCe7o2RVWtT8IlaiQphjsstA9H3f0M?= =?Windows-1252?Q?zFKMispg/6ivtfH7JWs0PYzzGpjRB9PuSQtTxGriMCwsxLqHCNYw9pcd?= =?Windows-1252?Q?0qE7g8oLTxaaSXKQBzCXBZTGPQCk9VQywQQXIjZpC87olrKqv6FEOh7K?= =?Windows-1252?Q?2o1kEcSu+/9rQrKKJCPGTQykatbtEK/2yVgP3ZQvAfD2p7yg6EHxXKGF?= =?Windows-1252?Q?9cGQM6qlNTGxKVGnV0sjJTUdesAPP3VZvKUmIFtoEHv37eWZq3CFVP4s?= =?Windows-1252?Q?H9s7t0Oy85SZtY9Nm0ayQhBprhuZYNvh+S8A+fBZ8bspRosiX62+a0za?= =?Windows-1252?Q?RoXf0vbni7pNe/IBNJ2Kg1szxoVeRZS8nB5MPmGMaAEnjMsbN0STiI53?= =?Windows-1252?Q?jyQ53tJCcW5Q8btwoA51of51Nf5Y5CIjtyNj0v0ZOViU+gCFR1wpFPE1?= =?Windows-1252?Q?ulgH1VEysC3e0s2fVN9+qDyFf9iMtlCo+2nWjxevKPOnEjJ3MtECRNVE?= =?Windows-1252?Q?+xZdcKvYqJUnm3jPWcyJq1bL5/mbWtf2/0rrbGeL3GRuChXeqGjnmvaF?= =?Windows-1252?Q?FQNM+W/l+rC+/ovH6bABKkgLaOgChSKcO6MsQXNivwAGvPYJug0YFHXF?= =?Windows-1252?Q?9R46eIXC/VfNkF+M3bI5Jbh14tf6Y0qQwTnp8+e2CtbvCPsXcNCgMXdp?= =?Windows-1252?Q?nx0c7Xbd45hCAwTs/i7sknBIGFexKaeD9yzrOHiivAaRH2xqMa6hjzsB?= =?Windows-1252?Q?H8wVHSlWf4QW193gRmwXvGdLeeXFEt/jMWhC0b2H7JxHgawcvY1qKNUh?= =?Windows-1252?Q?Zrxxk6pajJwsGqI4162I0PURDsgndVo/R3nzEvmBfsAy+tTjxLpXY2mR?= =?Windows-1252?Q?Y0x7SM7Y688AbW6V0AMt7VAB2IgsCZWElFtnSQ=3D=3D?= x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:YQXPR01MB4198.CANPRD01.PROD.OUTLOOK.COM;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(38070700018)(8096899003);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?Windows-1252?Q?GW9S1vo1TsfE+I7yYVDgwaAdVgeQYRosH2GjHsyW0HS3kqAGovRHBo6R?= =?Windows-1252?Q?bO72vF4nnlLqxuzuIGVKkkv6J5OMgimReXa5aZ6/QhMsmNIH4EBF9RHl?= =?Windows-1252?Q?lHJJQzk9o4S/lsjhEJbTraLBieBlgn5BX9yA3C/wRcOw9+idr/09X4Sm?= =?Windows-1252?Q?Ne7ZXrMxY+ta8O4E1MlcY+M4+EbjiZ69+8gZO8ozMamQ8ZQdg6mV6RRZ?= =?Windows-1252?Q?Qvsr5L0fOji2zTa0KBdM3mFi4kT4wCZM3u5vHieqruk8fMe3KPfHBGey?= =?Windows-1252?Q?ndZT1PK5+x35zTNBi3SfGTc+gJgTtmfRdiEqTA6I8Ob28HCA9Eoa6rO1?= =?Windows-1252?Q?filLRto2Pp7WiG1IkD9MbaUP1tR9g1+91CsQs3aYy5Vq97sb79R8SIlS?= =?Windows-1252?Q?g/rneR+a0uzgtWlJAkvn6jcaziXH481Q0GJJ45fBX59L6lRu3ac+eoGr?= =?Windows-1252?Q?2AXZBPS6aQ4GWtQSwfIkFxFO3JqoEfLSMNPpv+idNTRe1/iiW2vV/mHL?= =?Windows-1252?Q?H35UNH+S8+DHBik641nq737TZbujS1a5dv6SHsm/OaWv1S4wus7W8/IW?= =?Windows-1252?Q?T6dPqyeI2AB7kQn3+iX6NF39IooK9ToHVcgbQvdQdW8A+QaS1a+PjPlg?= =?Windows-1252?Q?AB7kNeue5jJkfPPMUovvB+RvTxFhVTfkn/WBEueYmvZwQInBblohV7nV?= =?Windows-1252?Q?S7P2kGFsm1r+bvZKzu/0Sj5CtPRMNcfzStT4KJMHIC0qiA/TJNyIfe+C?= =?Windows-1252?Q?VYl8YK1jJgdIdfCBqO4neyDkO32elmAILqj52jTSgkpXYBv1aY0XQGuE?= =?Windows-1252?Q?c3JHTVMThobQN6sqH2Czef8LDv+HkzjxYb+VD9XCtONJKHZ/WiZiH8bR?= =?Windows-1252?Q?u/SFy6WOqricICcra//c3fqcsQmJr5BRE4CbV9QwATsVbXfGI6Jq2jNQ?= =?Windows-1252?Q?hBWUoYbTk0ch958NlRNG/2bpQQc10Janf3NX0e2b0isf8FKByJJ6e+me?= =?Windows-1252?Q?lKlSJ1ElMdwbhhMYUjlWYQZkk0Yaw0SKBfD3M/DfeqD0xNURsPIAhPfv?= =?Windows-1252?Q?z2ISkeJMo8HrE5unkEFwjqENxO7ElTUOFmYiGeCukM9r2w1mgL8nc/Ck?= =?Windows-1252?Q?xbtftkWPmHsRDEA5PRXuGBpjcTf7AaY6PUtVXh7r50UMej0YM816UVl+?= =?Windows-1252?Q?7P8rJIi/7vOe4XApL3a0ca2g86bXSHcSClRTdJL7yiaUBksO2xugx0il?= =?Windows-1252?Q?jQFLG1XMaDqXzyjazKXvUUavB0ahq0c2XuFINkpDEUgidsvzlntwo81e?= =?Windows-1252?Q?Uo5RmnfLrv+6TxcBRug+HfYZ0E00bAZD1xdlfLs8gwm4jHHtQuf5A5pZ?= =?Windows-1252?Q?+S3eW2r+83/khqKPADl94CKRDoFwao/v6nj0cxKTkR1EVGKXGizmSxh0?= =?Windows-1252?Q?M2hY4vgEA4kXxl+06239Ynm/dumXa8MTe/NlBs8BQIpDR0c+ebQQCvFJ?= =?Windows-1252?Q?JpdeZT7YQfHUefYxEk36+QJmPIbcvMme2xaq2iB6yTThd/+AZQTv6+Ou?= =?Windows-1252?Q?N/OwCAxdXfI2RA257O8ke4uQxMdXuFM0Tqb9EnR0qOyH4cXugFYm1uUd?= =?Windows-1252?Q?CsbsoJIOwhB2npRRPbI4/H7CGhJppX6Sa+5p+BRTMO9ay0tSJ4We7lTI?= =?Windows-1252?Q?skpspOVWWi0z+FOU1/qihLc0wqj/kIb+m4i4GH/nrH/yj7ypRf8xpA?= =?Windows-1252?Q?=3D=3D?= Content-Type: multipart/alternative; boundary="_000_YQXPR01MB41989535A01FA09637C82906C2822YQXPR01MB4198CANP_" List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@FreeBSD.org MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: YQXPR01MB4198.CANPRD01.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-Network-Message-Id: 540831ef-e7e1-4e08-d9ea-08dd88b1f7a9 X-MS-Exchange-CrossTenant-originalarrivaltime: 01 May 2025 13:13:30.2137 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 7fe064f1-1f82-4006-b05f-62ea659f38b0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: F12+niTnpmQNzSnySFvcwFFnEbH4o8/LCX9Te6JZDdC5E3hQDwEgA9GqvnMh6SSND96UOymivlv+aOog6/DjeZQmhLA+yPJDSrY7frc7JIM= X-MS-Exchange-Transport-CrossTenantHeadersStamped: YT3PR01MB9314 X-OriginatorOrg: qnx.com X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.736,FMLib:17.12.80.40 definitions=2025-05-01_04,2025-04-24_02,2025-02-21_01 X-Rspamd-Queue-Id: 4ZpDyc2H3yz3C29 X-Spamd-Bar: + X-Spamd-Result: default: False [1.25 / 15.00]; ARC_REJECT(1.00)[signature check failed: fail, {[1] = sig:microsoft.com:reject}]; NEURAL_SPAM_MEDIUM(0.99)[0.992]; NEURAL_SPAM_LONG(0.99)[0.987]; NEURAL_HAM_SHORT(-0.73)[-0.732]; DMARC_POLICY_ALLOW_WITH_FAILURES(-0.50)[]; R_SPF_ALLOW(-0.20)[+ip4:208.65.78.89]; R_DKIM_ALLOW(-0.20)[qnx.com:s=pfpt20241003]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; DKIM_TRACE(0.00)[qnx.com:+,blackberryltd.onmicrosoft.com:-]; RCPT_COUNT_ONE(0.00)[1]; MISSING_XM_UA(0.00)[]; ASN(0.00)[asn:18705, ipnet:208.65.76.0/22, country:CA]; RCVD_IN_DNSWL_NONE(0.00)[40.93.18.48:received]; MIME_TRACE(0.00)[0:+,1:+,2:~]; DMARC_POLICY_ALLOW(0.00)[qnx.com,none]; DKIM_MIXED(0.00)[]; RCVD_TLS_LAST(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; MLMMJ_DEST(0.00)[freebsd-net@freebsd.org]; R_DKIM_REJECT(0.00)[blackberryltd.onmicrosoft.com:s=selector2-blackberryltd-onmicrosoft-com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TO_DN_EQ_ADDR_ALL(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-net@freebsd.org]; RCVD_COUNT_SEVEN(0.00)[7] --_000_YQXPR01MB41989535A01FA09637C82906C2822YQXPR01MB4198CANP_ Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="windows-1252" There appears to be a race condition in ether_ifattach (if_ethersubr.c). The ether_ifattach() function calls if_attach, where the interface will get= announced, and then ether_ifattach continues with the initialization of th= e ifp. Is there any guarantee in FreeBSD that this race condition cannot be expose= d. We have been running the FreeBSD stack for some time under QNX and have jus= t recently run into an issue with this race condition. We are considering a modification where we have the option of deferring the= interface announcement in if_attach. Before opening a FreeBSD bug, I wanted to check if this issue would not be = valid in a FreeBSD system. It=92s very clear that there is a potential race when looking at the code, = but perhaps there is a mitigation that is not obvious. ---------------------------------------------------------------------- This transmission (including any attachments) may contain confidential info= rmation, privileged material (including material protected by the solicitor= -client or other applicable privileges), or constitute non-public informati= on. Any use of this information by anyone other than the intended recipient= is prohibited. If you have received this transmission in error, please imm= ediately reply to the sender and delete this information from your system. = Use, dissemination, distribution, or reproduction of this transmission by u= nintended recipients is not authorized and may be unlawful. --_000_YQXPR01MB41989535A01FA09637C82906C2822YQXPR01MB4198CANP_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="windows-1252"

There appears to be= a race condition in ether_ifattach (if_ethersubr.c).

The ether_ifattach(= ) function calls if_attach, where the interface will get announced, and the= n ether_ifattach continues with the initialization of the ifp.

Is there any guaran= tee in FreeBSD that this race condition cannot be exposed.

We have been runnin= g the FreeBSD stack for some time under QNX and have just recently run into= an issue with this race condition.

We are considering = a modification where we have the option of deferring the interface announce= ment in if_attach.

Before opening a Fr= eeBSD bug, I wanted to check if this issue would not be valid in a FreeBSD = system.

It=92s very clear t= hat there is a potential race when looking at the code, but perhaps there i= s a mitigation that is not obvious.

This transmission (including any attachments) may contain confidential = information, privileged material (including material protected by the solic= itor-client or other applicable privileges), or constitute non-public infor= mation. Any use of this information by anyone other than the intended recip= ient is prohibited. If you have received this transmission in error, please= immediately reply to the sender and delete this information from your syst= em. Use, dissemination, distribution, or reproduction of this transmission = by unintended recipients is not authorized and may be unlawful.
--_000_YQXPR01MB41989535A01FA09637C82906C2822YQXPR01MB4198CANP_--