From patchwork Thu Aug 11 09:48:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Kochetkov X-Patchwork-Id: 12941304 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71100C19F2A for ; Thu, 11 Aug 2022 09:48:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233884AbiHKJsr (ORCPT ); Thu, 11 Aug 2022 05:48:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229724AbiHKJsr (ORCPT ); Thu, 11 Aug 2022 05:48:47 -0400 X-Greylist: delayed 1603 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 11 Aug 2022 02:48:45 PDT Received: from smtpng1.i.mail.ru (smtpng1.i.mail.ru [94.100.181.251]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE6DD9082B; Thu, 11 Aug 2022 02:48:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=inbox.ru; s=mail4; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject:Cc:To:From:From:Subject:Content-Type:Content-Transfer-Encoding:To:Cc; bh=I7Ayg1KJiv/lsQm9ztBCqNb2erJhN1SxZDb2jBhynJQ=; t=1660211326;x=1660301326; b=S+xkdw2O9GXq18YuAK7w4Z1VS5RYKMAeZ/6sKy5HgnuViarIewjw7FeilP0atY2T7iTNFQUd/2p6Tyir/uO3JpTgNZd2Fo8wFMYoVxWCwOCk1tY2MtHqs3TbBPp+wDhiKd8omwmexKm1kuyCgBwZA+SYSkBDIDL30vCi1CsoIgTdVvLtGisnq7XnifWXc896F+SK02wMHmUGFjXyf+qTLPPX3cccXp26bRwDvsW3SlRQWv8coWC0X2wJmwXAwHShl4E3jQw/gbKq+CdCM7X8Ap5347ZOcRDHwAogNTHYWH2VbcOXENaxIqqrX+bkYRjkbGdlVr9dVvg3eRxuj0+ZbQ==; Received: by smtpng1.m.smailru.net with esmtpa (envelope-from ) id 1oM4nz-0000WO-9j; Thu, 11 Aug 2022 12:48:43 +0300 From: Maxim Kochetkov To: netdev@vger.kernel.org Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-arm-msm@vger.kernel.org, Maxim Kochetkov , Hemant Kumar , Manivannan Sadhasivam Subject: [PATCH v2 1/1] net: qrtr: start MHI channel after endpoit creation Date: Thu, 11 Aug 2022 12:48:40 +0300 Message-Id: <20220811094840.1654088-1-fido_max@inbox.ru> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Authentication-Results: smtpng1.m.smailru.net; auth=pass smtp.auth=fido_max@inbox.ru smtp.mailfrom=fido_max@inbox.ru X-Mailru-Src: smtp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eAau8CL7WIMRKs4sN3D3tLDjz0dLbV79QFUyzQ2Ujvy7cMT6pYYqY16iZVKkSc3dCLJ7zSJH7+u4VD18S7Vl4ZUrpaVfd2+vE6kuoey4m4VkSEu530nj6fImhcD4MUrOEAnl0W826KZ9Q+tr5ycPtXkTV4k65bRjmOUUP8cvGozZ33TWg5HZplvhhXbhDGzqmQDTd6OAevLeAnq3Ra9uf7zvY2zzsIhlcp/Y7m53TZgf2aB4JOg4gkr2biojfXJM3siCnCmYS7facU8ebA== X-Mailru-Sender: 689FA8AB762F7393CC2E0F076E87284E12C8D11CC8D54F216789068519F65BC498CC072019C18A892CA7F8C7C9492E1F2F5E575105D0B01ADBE2EF17B331888EEAB4BC95F72C04283CDA0F3B3F5B9367 X-Mras: Ok Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org MHI channel may generates event/interrupt right after enabling. It may leads to 2 race conditions issues. 1) Such event may be dropped by qcom_mhi_qrtr_dl_callback() at check: if (!qdev || mhi_res->transaction_status) return; Because dev_set_drvdata(&mhi_dev->dev, qdev) may be not performed at this moment. In this situation qrtr-ns will be unable to enumerate services in device. --------------------------------------------------------------- 2) Such event may come at the moment after dev_set_drvdata() and before qrtr_endpoint_register(). In this case kernel will panic with accessing wrong pointer at qcom_mhi_qrtr_dl_callback(): rc = qrtr_endpoint_post(&qdev->ep, mhi_res->buf_addr, mhi_res->bytes_xferd); Because endpoint is not created yet. -------------------------------------------------------------- So move mhi_prepare_for_transfer_autoqueue after endpoint creation to fix it. Fixes: a2e2cc0dbb11 ("net: qrtr: Start MHI channels during init") Signed-off-by: Maxim Kochetkov Reviewed-by: Hemant Kumar Reviewed-by: Manivannan Sadhasivam Reviewed-by: Loic Poulain --- net/qrtr/mhi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/net/qrtr/mhi.c b/net/qrtr/mhi.c index 18196e1c8c2f..9ced13c0627a 100644 --- a/net/qrtr/mhi.c +++ b/net/qrtr/mhi.c @@ -78,11 +78,6 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, struct qrtr_mhi_dev *qdev; int rc; - /* start channels */ - rc = mhi_prepare_for_transfer_autoqueue(mhi_dev); - if (rc) - return rc; - qdev = devm_kzalloc(&mhi_dev->dev, sizeof(*qdev), GFP_KERNEL); if (!qdev) return -ENOMEM; @@ -96,6 +91,13 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, if (rc) return rc; + /* start channels */ + rc = mhi_prepare_for_transfer_autoqueue(mhi_dev); + if (rc) { + qrtr_endpoint_unregister(&qdev->ep); + return rc; + } + dev_dbg(qdev->dev, "Qualcomm MHI QRTR driver probed\n"); return 0;