From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6CFADC4338F for ; Mon, 2 Aug 2021 06:47:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AF7F60F11 for ; Mon, 2 Aug 2021 06:47:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232306AbhHBGrl (ORCPT ); Mon, 2 Aug 2021 02:47:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:42152 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231410AbhHBGrk (ORCPT ); Mon, 2 Aug 2021 02:47:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DDCDC61050; Mon, 2 Aug 2021 06:47:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627886851; bh=tjOcz9TZwEilKhNtlP5WqvCRmPhGzI0gl+EwjDc+HBA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ng8FQr2g9SjFNOQwHzCK6iMvebQZbGLkYUSig262N6LJuTyz4WrUusDAqQTZ1igVI ySbEUBjlKlTmv7MzBkLkG1WGZklpi9A4jrPl4SPpRE1MO/nSZPani/QdsCav8CDFiE +vo91xH7FUgSE57VV45a2TysBsX5WPoCe+y3VhO8V9XPk2OEbF0xHSt4xzZgsmBFX6 wDLMd9EsQCBXwb03XZjOtQR6bLJc+LYsPnz7vWr6IjKSZXSlGlOUssNufLOG0SuFZo gIPx0xqLJqZ5BEEuE3SVQbcbBHFsrp0+pGrrYjBAWLKhWCqYzPDd71HEs34lycM6cn B8XQsCO2gay9g== Date: Mon, 2 Aug 2021 09:47:28 +0300 From: Leon Romanovsky To: Jack Wang Cc: linux-rdma@vger.kernel.org, bvanassche@acm.org, dledford@redhat.com, jgg@ziepe.ca, haris.iqbal@ionos.com, Gioh Kim Subject: Re: [PATCH for-next 02/10] RDMA/rtrs-srv: Prevent sysfs error with path name "ctl" Message-ID: References: <20210730131832.118865-1-jinpu.wang@ionos.com> <20210730131832.118865-3-jinpu.wang@ionos.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210730131832.118865-3-jinpu.wang@ionos.com> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Fri, Jul 30, 2021 at 03:18:24PM +0200, Jack Wang wrote: > From: Gioh Kim > > If the client tries to create a path with name "ctl", > the server tries to creates /sys/devices/virtual/rtrs-server/ctl/. > Then server generated below error because there is already ctl directory > which manages some setup of the server. > > sysfs: cannot create duplicate filename '/devices/virtual/rtrs-server/ctl' > Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] > Call Trace: > dump_stack+0x50/0x63 > sysfs_warn_dup.cold+0x17/0x24 > sysfs_create_dir_ns+0xb6/0xd0 > kobject_add_internal+0xa6/0x2a0 > kobject_add+0x7e/0xb0 > ? _cond_resched+0x15/0x30 > device_add+0x121/0x640 > rtrs_srv_create_sess_files+0x18f/0x1f0 [rtrs_server] > ? __alloc_pages_nodemask+0x16c/0x2b0 > ? kmalloc_order+0x7c/0x90 > ? kmalloc_order_trace+0x1d/0xa0 > ? rtrs_iu_alloc+0x17e/0x1bf [rtrs_core] > rtrs_srv_info_req_done+0x417/0x5b0 [rtrs_server] > ? __switch_to_asm+0x40/0x70 > __ib_process_cq+0x76/0xd0 [ib_core] > ib_cq_poll_work+0x26/0x80 [ib_core] > process_one_work+0x1df/0x3a0 > worker_thread+0x4a/0x3c0 > kthread+0xfb/0x130 > ? process_one_work+0x3a0/0x3a0 > ? kthread_park+0x90/0x90 > ret_from_fork+0x1f/0x40 > kobject_add_internal failed for ctl with -EEXIST, don't try to register things with the same name in the same directory. > rtrs_server L178: device_add(): -17 > > This patch checks the path name and disconnect on server to prevent > the kernel error. > > Signed-off-by: Gioh Kim > Signed-off-by: Jack Wang > --- > drivers/infiniband/ulp/rtrs/rtrs-srv.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > index cd9a4ccf4c28..b814a6052cf1 100644 > --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c > +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > @@ -758,6 +758,14 @@ static bool exist_sessname(struct rtrs_srv_ctx *ctx, > struct rtrs_srv_sess *sess; > bool found = false; > > + /* > + * Session name "ct" is not allowed because > + * /sys/devices/virtual/rtrs-server/ctl already exists > + * for setup management. > + */ > + if (!strcmp(sessname, "ctl")) > + return true; Why does it have special treatment? And what will happen if user supplies "." or ".."? Does rtrs receive this session name from the other side in the network? Thanks