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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B7C3C433F5 for ; Wed, 30 Mar 2022 11:01:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245715AbiC3LDd (ORCPT ); Wed, 30 Mar 2022 07:03:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245693AbiC3LDV (ORCPT ); Wed, 30 Mar 2022 07:03:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE7D5C5584 for ; Wed, 30 Mar 2022 04:01:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3BBBD6150C for ; Wed, 30 Mar 2022 11:01:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22B71C34115; Wed, 30 Mar 2022 11:01:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1648638094; bh=1EvLJBCGXjG2NfRoEoOmIymXZKHcYWtj2sCw1Ecw1eg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EHdArsRoaLYh/rBOg3MsicDkGjVUeJ5GhPxXCujnxAE9IWju6cwICX1fFEBEysi8k bDrG77mVCfxfhvY6hyIf9ksQmjF0dTizHug2EMSEJ3CXW2slwFns8HRYEDNTVo5Re2 QpxJdwHJyN2TMxl33pSoIaGu9wLIy4uwcmqbVVQ4= Date: Wed, 30 Mar 2022 13:01:31 +0200 From: Greg KH To: Mukesh Ojha Cc: "Rafael J. Wysocki" , linux-kernel@vger.kernel.org Subject: Re: Possible case of Race in kobject_get_path() Message-ID: References: <0410ceda-cbdd-43a9-7d9b-4079bcdb6237@quicinc.com> <148f4e9b-0584-ccc1-1443-30d41190dfd3@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <148f4e9b-0584-ccc1-1443-30d41190dfd3@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 30, 2022 at 04:14:11PM +0530, Mukesh Ojha wrote: > > On 3/30/2022 3:46 PM, Greg KH wrote: > > On Wed, Mar 30, 2022 at 03:41:04PM +0530, Mukesh Ojha wrote: > > > Hi All, > > > > > > We are facing one issue where one driver (p1) is trying to register its > > > device from driver probe > > > and from another path (p2) dev_set_name(new name) done from driver probe of > > > the added device whose > > > new name length can be more than earlier done in (p1 path) which could > > > result in redzone overwritten issue. > > I do not understand, what specific driver is doing this so that we can > > see an example of this problem? > > >> > > trying to paste some logs of the race. > > [ 14.235820][ T503] BUG kmalloc-128 (Tainted: G S O ): Left Redzone > overwritten What kernel version is this? > [ 14.244189][ T503] > ----------------------------------------------------------------------------- > [ 14.255241][ T503] INFO: 0xffffff87caae0f7d-0xffffff87caae0f7f > @offset=3965. First byte 0x2f instead of 0xcc > [ 14.265176][ T503] INFO: Allocated in kobject_get_path+0x58/0x100 age=1 > cpu=0 pid=503 > [ 14.273111][ T503] kobject_get_path+0x58/0x100 > [ 14.277747][ T503] kobject_uevent_env+0x120/0x744 > [ 14.282639][ T503] device_add+0x98c/0x1028 > [ 14.286925][ T503] *device_register+0x24/0x38* > [ 14.291395][ T503] slim_alloc_device+0xdc/0x108 [slimbus] > [ 14.296992][ T503] slim_register_controller+0x210/0x2ac [slimbus] > [ 14.303291][ T503] qcom_slim_ngd_probe+0x3c/0x348 [slim_qcom_ngd_ctrl] > [ 14.310007][ T503] platform_drv_probe+0x60/0x180 > [ 14.314812][ T503] really_probe+0x208/0xb64 > [ 14.319184][ T503] driver_probe_device+0x130/0x254 > [ 14.324159][ T503] __device_attach_driver+0x1e8/0x324 > [ 14.329399][ T503] __device_attach+0x170/0x364 > [ 14.334035][ T503] bus_probe_device+0x4c/0x164 > [ 14.338671][ T503] device_add+0xa60/0x1028 > [ 14.342957][ T503] platform_device_add+0x260/0x2c8 > [ 14.347941][ T503] qcom_slim_ngd_ctrl_probe+0x71c/0x804 > [slim_qcom_ngd_ctrl] > [ 14.355177][ T503] INFO: Freed in kobject_uevent_env+0x210/0x744 age=1 > cpu=4 pid=518 > [ 14.363018][ T503] do_init_module+0xac/0x494 > [ 14.367475][ T503] load_module+0x35c0/0x3e54 > [ 14.371930][ T503] __se_sys_finit_module+0x188/0x1c8 > [ 14.377086][ T503] __arm64_sys_finit_module+0x20/0x30 > [ 14.382328][ T503] el0_svc_common+0xdc/0x294 > [ 14.386786][ T503] el0_svc+0x38/0x9c > [ 14.390552][ T503] el0_sync_handler+0x8c/0xf0 > > > [ 14.490994*][ T503] Redzone ffffff87caae0f7**0*: cc cc cc cc cc cc cc cc cc > cc cc cc cc 2f 64 65 .............*/de* > [ 14.501185][ T503] Object ffffff87caae0f80: 76 69 63 65 73 2f 70 6c 61 74 > 66 6f 72 6d 2f 73 vices/platform/s > [ 14.511376][ T503] Object ffffff87caae0f90: 6f 63 2f 33 33 34 30 30 30 30 > 2e 73 6c 69 6d 2f oc/3340000.slim/ > [ 14.521566][ T503] Object ffffff87caae0fa0: 71 63 6f 6d 2c 73 6c 69 6d 2d > 6e 67 64 2e 31 2f qcom,slim-ngd.1/ > [ 14.531757][ T503] Object ffffff87caae0fb0: 62 74 66 6d 73 6c 69 6d 5f 73 > 6c 61 76 65 00 00 *btfmslim_slave*.. > > > > 499 static int btfm_slim_probe(struct slim_device *slim) I do not see that function in Linus's tree right now. Where does it come from? thanks, greg k-h