From nobody Sat Sep 26 04:30:04 2026 Received: from DB3PR0202CU003.outbound.protection.outlook.com (mail-northeuropeazon11020112.outbound.protection.outlook.com [52.101.84.112]) (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 05862368974; Fri, 4 Sep 2026 13:54:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.84.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788530085; cv=fail; b=u0TiOR360JzbDSwobxqk7m9Q5bpD7cFtYxvtecGIA5Yoan9YcWDwtMINfLYn8vN1ueRc1a9RMaEyAwb6PSQ1wHQ6gwTKPs1oekTKnMnjJzbyS/2fuBoWDhby8bGdcqOnU1AfPYeVATMqYxZQPcaxFFdnfgPDHUEuB7AK7qrWCmY= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788530085; c=relaxed/simple; bh=p3hEreqki7xtJCq9/i8+7mTf+U18d/TxyLGZn3jZa/I=; h=From:To:CC:Subject:Date:Message-ID:Content-Type:MIME-Version; b=i/jr+A22CwYPIhnZI9DVzK4NpfwZMS2cMh2zsTrThbbjzIEeZgEpTBQONuk6gXC2K/fT6l3cATa7/ryjbO+ZFjo5clkpHFUMTGNZd0gOHze8TfsIpLfW6xlAs2stLqDNplOw8+Ah7nM58iuLdeaWBTToFMild3/0lxg2ipkpd+I= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=drivesec.com; spf=pass smtp.mailfrom=drivesec.com; dkim=pass (2048-bit key) header.d=drivesec.com header.i=@drivesec.com header.b=AATGinbC; arc=fail smtp.client-ip=52.101.84.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=drivesec.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=drivesec.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=drivesec.com header.i=@drivesec.com header.b="AATGinbC" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=j46//F8IDoRztHR2Xpj0Fx0CKii9eO4GwQKtRPHdW3qqyeJ2JIz/J1w2rx1fTr+xQlWo6WfhjTpyWW+ReupEdA4est6cme4cZ5cfZp42s5eHRo8SLG0Xw0dUQ6GU42YHiaaNZv1HWqWINYAwWGHCKpoPMvTYgEyAxRQByHAOlM4UC8Wix2OeJqFSJ8HQq3CV99OWdbESFkniPZnPqZqC0z7Fjajedhz+dP8YdTQHMO3JhmsTD3UKvEDeuUSzFvQZwz/BVavKzKwit5EUtzCGcxQoIT7PiOFexPoJEgL1ox/UQShNOX9zrhs1XJ0xFtd3ZyIPQHjO/d4Y/yk87IwKKQ== 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=JLMtsV1bNn7InwDGkMAdLRgw2TXBSQngCT/g0xZRqxw=; b=wPCOvfmNTDfzkXAKWy9cBohtNg//KxTGnnudds49tonmp8aLWiUtyXpRqcpJ+DN3UVDq3eh+gCrzoPHQQ9OcbVmEcUhjQB3uZ5NikE8J/X0GJdsCoVx5/hL9VSUoq50M8g3GJxWcA1AHh1j63gDaEouw1O99P233Hp4dR03dH9fIzw8mvodSOnCDGMcNcPn3cRqlezLsAzw6mdDJlEabC2w32PoqN0zfz8e8S3axKtoLluat2MBd6Yx5FWaHYn4Zy68SMbytuc8hOJWJQe3OWMuFt7QiW0HFfrWOXTLmBXHM98OzL+e70yHDTaZ5C9nR1wk7XnUSVS/XkGnBiVO1Zw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=drivesec.com; dmarc=pass action=none header.from=drivesec.com; dkim=pass header.d=drivesec.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=drivesec.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=JLMtsV1bNn7InwDGkMAdLRgw2TXBSQngCT/g0xZRqxw=; b=AATGinbCREioEGSsl+jsVTGOW019RxEl3hIICTdbNFx3mXOXymy3TunWACLKDfLOPmKoOlO9rimtdVrNEAnAhLDAdwQrwpZbAILhtn3fJTdknLFHKcJTAbEtPxWWwZxtzOEfkkuCfFXC2nQQE5DNAJeJGPQALXVWAdjjphoj4MQ5W97VACwOgu5WcGVBeg9QCZT7I+80dkK2GDg+sQFlA2iXbewFVl2fChMj3Ifa7SO+hIAZWTgOND4DDmkdOWCiNNnwJv6tYizpfgsSwV6hNlMkUGQlHzHJxFtRsBp44htx0zfZnnqf75sfDQDQQzCcHM5LBtot3iLvlijobL/00g== Received: from DU4P193MB3185.EURP193.PROD.OUTLOOK.COM (2603:10a6:10:63e::21) by AM9P193MB1048.EURP193.PROD.OUTLOOK.COM (2603:10a6:20b:1f2::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.360.13; Fri, 4 Sep 2026 13:54:37 +0000 Received: from DU4P193MB3185.EURP193.PROD.OUTLOOK.COM ([fe80::95bc:70d1:d001:69a9]) by DU4P193MB3185.EURP193.PROD.OUTLOOK.COM ([fe80::95bc:70d1:d001:69a9%5]) with mapi id 15.21.0360.008; Fri, 4 Sep 2026 13:54:37 +0000 From: Alberto Carboneri To: "James E . J . Bottomley" , "Martin K . Petersen" CC: Flavian Dei , Willy Tarreau , Hannes Reinecke , Niklas Cassel , Damien Le Moal , "linux-scsi@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: [PATCH] scsi: core: Validate MODE SENSE lengths in scsi_cdl_enable() Thread-Topic: [PATCH] scsi: core: Validate MODE SENSE lengths in scsi_cdl_enable() Thread-Index: AQHdPHTsccjEq9C3OkWhHO9dT1wahg== Date: Fri, 4 Sep 2026 13:54:37 +0000 Message-ID: <20260904135410.360314-1-acarboneri@drivesec.com> Accept-Language: it-IT, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=drivesec.com; x-ms-publictraffictype: Email x-ms-traffictypediagnostic: DU4P193MB3185:EE_|AM9P193MB1048:EE_ x-ms-office365-filtering-correlation-id: ed18777f-35f3-413a-927b-08df0a8c0f0e x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0;ARA:13230040|366016|1800799024|23010399003|376014|10067099003|6133799003|56012099006|18002099003|38070700021; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DU4P193MB3185.EURP193.PROD.OUTLOOK.COM;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(23010399003)(376014)(10067099003)(6133799003)(56012099006)(18002099003)(38070700021);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?iso-8859-1?Q?FWstsQkxP8cy1uDYSFj/8KnW8QrtSE6dgTMkGVk9iAdOeWQTifEB5PQlL1?= =?iso-8859-1?Q?z6eBRyD28teCPnBvfPNI7PkGTma+PeoXPbh4lpGekk18ESe/7lXVBVrrxE?= =?iso-8859-1?Q?wzBQRzYOeipGALVW4qQUuse/TrfPPf335z6iADIyiK439SBGLyaUsxKerX?= =?iso-8859-1?Q?iYJXbvqY/N314LPQ80WDotPkHENae1QDZ0ZkhfcLSVsDHd8sjLDhuH61kH?= =?iso-8859-1?Q?/NUJf5YayMMmgZ0+YXNnRhanbkm04N3SefucHr9SM9pAAFNb5+9aSUV7hR?= =?iso-8859-1?Q?vNUEUkDaPY6zoJsjEWCPLfbIQLCSpSskX57n0LQ8bXAhZ4mFzYgNT3HHIo?= =?iso-8859-1?Q?zsD9fnsfnxysBqyPf6xlkScnaqCgrqsmUplJRq+tGhw/Vnzg4GsPnoJtCi?= =?iso-8859-1?Q?ePNHYC1DDFFn0Vo25h2pE5rtCpPOEcrJkR95VZmngExJyli+nRkSpZJAHR?= =?iso-8859-1?Q?m0wVTBLGHcYbPbKRqrVNWbJHlkO3hS8FqkCnuZMBnYnbXV6mJsUZ6mdp1B?= =?iso-8859-1?Q?ZMGVYIrNJcEsJRBlt6ZJzIPe/6JU+DmpB7JEH3wqPX5aYf6j5Xqfm5XON3?= =?iso-8859-1?Q?NUKK3hvZqFBgkq80W0/dIPu9Px5ZlxUFNsTTL+c+jlxs1PK1ImsN/4WWPK?= =?iso-8859-1?Q?EQs7EQ6Hvwcc44O9irbmKoZHjsMxdQTcJMcxjOnfe1N+WtsLErKn4H7FMx?= =?iso-8859-1?Q?njaa6gkkmRtdKNuoaIdkFYuTl7+TNd26OJN2AUqQecXPw90y7euwgTHTJM?= =?iso-8859-1?Q?oYwMMdzCQA14UwHYZTxLgVnatbe4KOdWwGAiKjC9QjyTa6yK9wD1bz0HJS?= =?iso-8859-1?Q?0aVXGI3S4jJfBQ1QIy5FB+TirkDAHSwGLQ3Gjl3Y+BOcQOoNbenNjn4T3h?= =?iso-8859-1?Q?oqjQreedJKLpTaxDkkE/KV9KvjXvKMpiZ4UGA5O2AsrYM/d291AUJwA7K8?= =?iso-8859-1?Q?WFPx6TsbslD2Y0D9oZgb/XJVt4/rlQY8+MN5AiLEaqhzP+tvVt5/P0FW0c?= =?iso-8859-1?Q?Y1NbNI0aUX9VaxeeSBuLNJCJ87ZHC69elA+oguAiMkCDX0JVULAclCr3k7?= =?iso-8859-1?Q?aDm6tdJR14LBjgH9vpF3HVdLWjBHfL8fF+QTZpWVOkXNkpPxP1qQpkvkwZ?= =?iso-8859-1?Q?A4UhSgB1PFwzEXhBi46OdU1OqGlm+6DT6eYgPWNlbwNxbQtAISDCbTdQ0C?= =?iso-8859-1?Q?grm2PetuN5XQSy8/UiUnB+Wdh8j6AgXypiJSZZaGsysOQgdzkldTZjrupd?= =?iso-8859-1?Q?NpnhRvbReX8tfYpR0Y8eEocDNGoCtwvnNSi4HMFgfJkuVPSlQBQfCkTMHP?= =?iso-8859-1?Q?20zIkIkFRjrtHr0SP2BsKzKa9MQGEKGmLiHq/sXYnCyi5ZeR9i+xWwavAb?= =?iso-8859-1?Q?VqZjm1ViCNIPRno0+ywxOZqyToIqrsUpDiv5/9hAZmkp8ry8ofMvlm6mQI?= =?iso-8859-1?Q?nkMTA7DzFwmfSfqvYtKDeCdgkEnmnyMSdKH1S+Rn9YqSpPdR60SKaDBH2b?= =?iso-8859-1?Q?f5Uiobvackw3+WJyxlmtncSjUfqtTSisiuXQYQKkcbtJqx+x1cxZQYr854?= =?iso-8859-1?Q?IS/K/Re03cM+WNz+HhXnup0fkBkNJvXzA7kwOcCxddBhoJZAiCeuLtr255?= =?iso-8859-1?Q?psqQh+NGW36GydZdMiCdW5Rs2m6PpQWfkNNMqdT5Lhh4Yw43sKJukh7Xk3?= =?iso-8859-1?Q?M4Vm21QbiPLjDB6GQQdBWye+6fuKNMtIFiAiTxS9pMAtp9hRGfxyjWys7C?= =?iso-8859-1?Q?taL7FDqAfYhcD+tD3cV/28k79vjVhNPiUvWebLqxv0XxOB?= 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 X-OriginatorOrg: drivesec.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: DU4P193MB3185.EURP193.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-Network-Message-Id: ed18777f-35f3-413a-927b-08df0a8c0f0e X-MS-Exchange-CrossTenant-originalarrivaltime: 04 Sep 2026 13:54:37.3735 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 366e08b4-8687-488d-b967-a9f52a74f642 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 0VzsiMffEcxoAJ67NICUuM1+D/lK6H8GxEM7IOLb9kjuw98maRbrGz4i4UQJcHBj6TNEmOvdGh2I80uThBbG+A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM9P193MB1048 Content-Type: text/plain; charset="utf-8" scsi_cdl_enable() uses length fields returned by MODE SENSE to locate the ATA feature mode page in a 64-byte stack buffer. A target can report a total length shorter than its mode header and block descriptors. The unsigned subtraction used for the MODE SELECT length can wrap, and the separately computed buf_data can point beyond buf. During automatic scan, enable is false, so the read-modify-write of buf_data[4] can clear the low two bits of a target-selected out-of-bounds stack byte. scsi_mode_select() can then copy up to 64 bytes from outside the buffer into the outgoing MODE SELECT payload, disclosing stack contents to the target. This is reachable while scanning a USB storage device that identifies as an ATA device and advertises CDL support. No filesystem mount or userspace access to the block device is required. On upstream commit cee9395acd80 ("Linux 7.3-rc1"), a build-specific, one-vCPU QEMU/Raw Gadget proof using QEMU-only multi-UDC allocator sampling executed a fixed proof command inside the guest and created a UID-0-owned marker during automatic enumeration, with KASLR and NX enabled. The issue was independently found during security research at Drivesec S.r.l. Cap the available length to the buffer size. Validate and consume the mode header and block descriptor lengths before using the page, and require the five bytes needed to access the CDL field. Fixes: 1b22cfb14142 ("scsi: core: Allow enabling and disabling command dura= tion limits") Reported-by: Sashiko AI Review Closes: https://lore.kernel.org/linux-scsi/20260717192313.93D791F000E9@smtp= .kernel.org/ Link: https://lore.kernel.org/linux-scsi/20260717222931.AC4EE1F000E9@smtp.k= ernel.org/ Link: https://lore.kernel.org/linux-scsi/df13ec87ac9b28e3b0a2d9eb26477e276f= f0278a.camel@HansenPartnership.com/ Cc: stable@vger.kernel.org Assisted-by: LLM Co-developed-by: Pimen Flavian Dei (Drivesec S.r.l.) Signed-off-by: Pimen Flavian Dei (Drivesec S.r.l.) Signed-off-by: Alberto Carboneri (Drivesec S.r.l.) Reviewed-by: Damien Le Moal --- Tested on x86-64: - GCC 13.3.0, W=3D1 drivers/scsi/scsi.o - Clang 18.1.3, W=3D1 drivers/scsi/scsi.o - Malformed BDL92 MODE SENSE regression, 3/3 fresh QEMU boots: scan continued with no MODE SELECT, disclosure, Oops, or panic - Applies cleanly to v6.12.107 drivers/scsi/scsi.c | 24 +++++++++++++++++++----- 1 file changed, 19 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 76cdad063f7b..f285521d9de6 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -727,6 +727,7 @@ int scsi_cdl_enable(struct scsi_device *sdev, bool enab= le) struct scsi_mode_data data; struct scsi_sense_hdr sshdr; char *buf_data; + size_t avail, offset; int len; =20 ret =3D scsi_mode_sense(sdev, 0x08, 0x0a, 0xf2, buf, sizeof(buf), @@ -735,11 +736,24 @@ int scsi_cdl_enable(struct scsi_device *sdev, bool en= able) return -EINVAL; =20 /* Enable or disable CDL using the ATA feature page */ - len =3D min_t(size_t, sizeof(buf), - data.length - data.header_length - - data.block_descriptor_length); - buf_data =3D buf + data.header_length + - data.block_descriptor_length; + avail =3D min_t(size_t, data.length, sizeof(buf)); + if (data.header_length > avail) + return -EINVAL; + + offset =3D data.header_length; + avail -=3D data.header_length; + + if (data.block_descriptor_length > avail) + return -EINVAL; + + offset +=3D data.block_descriptor_length; + avail -=3D data.block_descriptor_length; + + if (avail < 5) + return -EINVAL; + + buf_data =3D buf + offset; + len =3D avail; =20 /* * If we want to enable CDL and CDL is already enabled on the base-commit: af8c27375733fb6a6df9fa484cda77cc3dd0cb80 --=20 2.43.0