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 5EA4D392831; Thu, 30 Jul 2026 15:18:23 +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=1785424704; cv=none; b=YAIYjJ2Gls/R7Cq1XywpKyO6hKbvJoPBs6dCcSd4MMnPdLMeosMHk1KFSRMjVFGHpTp+fpZa1GO9iw9beaG1KMV0zKXfrFrAw2zS9AqOVf0vNxx5lCNZFbn9J+VjffC0ptLPNvX6i0SVoSl5NZIOUHQdj1JUaQKemnsL2YeZGBM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785424704; c=relaxed/simple; bh=tpsVFlNw/IihU9d9VyHNxu+AL+z2R/hmyrEEOk65J+M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=n4k5f5fVVa2sFL2IpY/lKSILkXLaaYVSwgz1KbaCBt25nf92YqW//19Gp7S5tr266aiQnLqWcZkELM33oOaMJqpw8hBNXAMI0BvBRKI9R6DEYqUJZQLByUbVUiz+zZ29NSiuagyRTJtobs1Eh830LHw/M0337eTbF3xHwsPSCAM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ushu6/kk; 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="ushu6/kk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA2861F000E9; Thu, 30 Jul 2026 15:18:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785424703; bh=GtHHSkLrtTBTlcXmL34OOr/D8nw04hcTyoRdWrE5SxA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ushu6/kksxGOQXsuo41AddEHKGzrb+wag5GjMelK0hyQe8AIjrc6oPa+B8TrVa8oe uEsEAeGoywWCS4RJiqv/zffiMZg97ShJaPb2E0SgmogAFBEaBsX2tEFiJk/eSAX0mv eClyNbrOFXOFK9LPjENh1s1cw7CyTrBI9sKnMGmM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , Menachem Adin , Alexander Usyskin Subject: [PATCH 6.18 486/675] mei: bus: access mei_device under device_lock on cleanup Date: Thu, 30 Jul 2026 16:13:36 +0200 Message-ID: <20260730141455.451694796@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@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 6.18-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 @@ -1317,15 +1318,16 @@ 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);