From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C656F442FD3; Thu, 30 Jul 2026 14:47:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785422878; cv=none; b=ZsDifCTuWRgPSd9tZfQmGqjPRr0HZ7aMeDODYq0zVWGIRrbjMfRkFTNdqhi6WoHgJpooQovfoS/xm7LSazMKOJZixNLFqd16IPqsaMUNQRk5jCT6vCTMANFpiZ/J8xNuxlqy2l8YhGeQYfOt3e7BB/KuDXpucjVu+iY/RsnMG74= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785422878; c=relaxed/simple; bh=1cvqugoFogODCLoQo+2FtmYq3cZWz2vXcAbY30L2Tng=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=e4TIA5udqsqE99l2PYkPk3+D914c3bAJLCN72fy4mBmdQdAhkCkhq+y39Wvbz09/a052g/YxosHmy9smwy5vD7/k5PlevZtDS1Zv1cmy7hqDBjr6hxnfgFKrN+M2bbgykltxHd04pbBjZaqA61lmhBr3N4VLzVz3DLE4pS0EqF8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=kLIaUH33; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="kLIaUH33" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 64A431F00A3A; Thu, 30 Jul 2026 14:47:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785422875; bh=TKfLsKMt1iAnnTvLED+QXZPRgp29ruN9AvkXIRuMhHc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=kLIaUH33O4ZncyfUY9+OMBSx7PcCpQI5zdXMpdo6bNbme5p5WkYM0kA8uhJb9JjJK LXelt0GdLGgqLtZRxBdDjef9ApkHkvkgoLAxLtMSVggn3rtyZdcuXY6ND1aNaj79wt LVOxOWH+3hrDshh3PQ6Mjs5zJmzFHweee2ZkChsQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , Menachem Adin , Alexander Usyskin Subject: [PATCH 7.1 586/744] mei: bus: access mei_device under device_lock on cleanup Date: Thu, 30 Jul 2026 16:14:19 +0200 Message-ID: <20260730141456.738828724@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141444.267951807@linuxfoundation.org> References: <20260730141444.267951807@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Usyskin commit f112ea910e554d58b4b39a4492b7d302f0f4204f upstream. Fix couple of problems in mei_cl_bus_dev_release(): mei_cl_flush_queues() is running without lock. bus->file_list access after mei_dev_bus_put(bus) can become a use-after-free if this was the last reference to bus. Protect queues cleanup and WARN traversal by device lock there to avoid the concurrent access problems. Move WARN traversal before mei_dev_bus_put(bus). This file uses bus variable name for mei_device, adjust code of mei_cl_bus_dev_release() to use bus variable too. Cc: stable Fixes: 35e8a426b16a ("mei: bus: Check for still connected devices in mei_cl_bus_dev_release()") Reviewed-by: Menachem Adin Signed-off-by: Alexander Usyskin Link: https://patch.msgid.link/20260705151259.3054795-1-alexander.usyskin@intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/bus.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -4,6 +4,7 @@ * Intel Management Engine Interface (Intel MEI) Linux driver */ +#include #include #include #include @@ -1330,15 +1331,16 @@ static void mei_dev_bus_put(struct mei_d static void mei_cl_bus_dev_release(struct device *dev) { struct mei_cl_device *cldev = to_mei_cl_device(dev); - struct mei_device *mdev = cldev->cl->dev; + struct mei_device *bus = cldev->bus; struct mei_cl *cl; - mei_cl_flush_queues(cldev->cl, NULL); - mei_me_cl_put(cldev->me_cl); - mei_dev_bus_put(cldev->bus); - - list_for_each_entry(cl, &mdev->file_list, link) - WARN_ON(cl == cldev->cl); + scoped_guard(mutex, &bus->device_lock) { + mei_cl_flush_queues(cldev->cl, NULL); + mei_me_cl_put(cldev->me_cl); + list_for_each_entry(cl, &bus->file_list, link) + WARN_ON(cl == cldev->cl); + } + mei_dev_bus_put(bus); kfree(cldev->cl); kfree(cldev);