From patchwork Thu Aug 22 13:40:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roger Quadros X-Patchwork-Id: 172025 Delivered-To: patch@linaro.org Received: by 2002:a92:d204:0:0:0:0:0 with SMTP id y4csp900801ily; Thu, 22 Aug 2019 06:40:47 -0700 (PDT) X-Google-Smtp-Source: APXvYqywG043TekPo7Vl3PosC4q349HHSaUjGRoT1DNfwaySuzcoP1HDhcwGJFGIj9RCNxC9H5I1 X-Received: by 2002:a17:902:a40d:: with SMTP id p13mr24294513plq.92.1566481247300; Thu, 22 Aug 2019 06:40:47 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1566481247; cv=none; d=google.com; s=arc-20160816; b=aXgYmad7Yw8u9ja7bJIlsqcXbx2r2xEM+4hpqfa6zsvj8GyZEx6wgt2SYyRBQvI7Dm xX1IUl6/xgMZj+pmFqrHJjLTWH8z7lb4eTv5J8Ll8u8AvLjWQFfasq4+efzRoaPIMbGX 1LzaJKgnG4C2sJbLkUTvtYhkvc4st7ibb91pCr2uQpINML3m2laRbsQz/23ZOQcTT8g4 PA67Uaja6VAdkgylE4AScktlXBykkL6GKfMdGq5RLofNvwlSsgCiYXpOHqTr89XIanur vbgMP6lMfQOCEgVwoK5syxDS3R3eAz++KoHmCUmy/xv5xsaAlkH5nNuemoXdyOi/JETW oTGg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:dkim-signature; bh=snaiQFyiKmw4m9JXHWRa9VJ1PxzA6iRYaZc9+TjBxdU=; b=S2EppNA1PfsBwsf+uiyn+/0Nh26UJkxNeCp0doA3NliZdJiECdU4otCZQfPsP6Q0tl BJxCAk1uwLIsPhUc0RR9Y244Z4dH5JizrIlfaOjR1bSv6BE3BspJWbaL5Xef7XVH2Vlf saIXISqousUAr/u/O3TyihLsh7HpDGIjQo+/HQEJ3hmfbt0dipCp8RXCd36QnbUeNQOF AUEKBC0qtxscNdyHnn6iuGjCK7MxYCZCzqaeJypMAjS2aZwBmDtO/C+rUlLgvXsNp0zB VHu6zLTCLFKfFuQn63IzURZlhKw6i8nI+pEOkjH5nxFjW1hy4d7QQ3zJnpaNLO5EHvJZ VNVw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@ti.com header.s=ti-com-17Q1 header.b="Dl9L/ISJ"; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=ti.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id l98si6598888plb.157.2019.08.22.06.40.47; Thu, 22 Aug 2019 06:40:47 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@ti.com header.s=ti-com-17Q1 header.b="Dl9L/ISJ"; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=ti.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389202AbfHVNkp (ORCPT + 28 others); Thu, 22 Aug 2019 09:40:45 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:47650 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389189AbfHVNko (ORCPT ); Thu, 22 Aug 2019 09:40:44 -0400 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id x7MDeVu5088189; Thu, 22 Aug 2019 08:40:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1566481231; bh=snaiQFyiKmw4m9JXHWRa9VJ1PxzA6iRYaZc9+TjBxdU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=Dl9L/ISJt/z8EpEiC5FrCtNUgGTZnlLYdWzZp7lFHGkEMWC7TtisKSejTcZz3crES NVyvLmvHH6kX/NS3YweMZCHvGOK808vwn0YKqAc0B81nxg6btppiRCvlXNLTGNBicO XzFwxmiZhgyy46y4ytaYaD4VUNLAolwC8BRzB7cI= Received: from DFLE109.ent.ti.com (dfle109.ent.ti.com [10.64.6.30]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x7MDeVAW009576 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 22 Aug 2019 08:40:31 -0500 Received: from DFLE101.ent.ti.com (10.64.6.22) by DFLE109.ent.ti.com (10.64.6.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Thu, 22 Aug 2019 08:40:31 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DFLE101.ent.ti.com (10.64.6.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Thu, 22 Aug 2019 08:40:31 -0500 Received: from lta0400828a.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id x7MDeT3P050012; Thu, 22 Aug 2019 08:40:29 -0500 From: Roger Quadros To: , CC: , , , Roger Quadros Subject: [PATCH v2] usb: gadget: udc: core: Fix segfault if udc_bind_to_driver() for pending driver fails Date: Thu, 22 Aug 2019 16:40:28 +0300 Message-ID: <20190822134028.2623-1-rogerq@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190821101201.5377-1-rogerq@ti.com> References: <20190821101201.5377-1-rogerq@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If a gadget driver is in the pending drivers list, a UDC becomes available and udc_bind_to_driver() fails, then it gets deleted from the pending list. i.e. list_del(&driver->pending) in check_pending_gadget_drivers(). Then if that gadget driver is unregistered, usb_gadget_unregister_driver() does a list_del(&driver->pending) again thus causing a page fault as that list entry has been poisoned by the previous list_del(). Fix this by using list_del_init() instead of list_del() in check_pending_gadget_drivers(). Test case: - Make sure no UDC is available - modprobe g_mass_storage file=wrongfile - Load UDC driver so it becomes available lun0: unable to open backing file: wrongfile - modprobe -r g_mass_storage [ 60.900431] Unable to handle kernel paging request at virtual address dead000000000108 [ 60.908346] Mem abort info: [ 60.911145] ESR = 0x96000044 [ 60.914227] Exception class = DABT (current EL), IL = 32 bits [ 60.920162] SET = 0, FnV = 0 [ 60.923217] EA = 0, S1PTW = 0 [ 60.926354] Data abort info: [ 60.929228] ISV = 0, ISS = 0x00000044 [ 60.933058] CM = 0, WnR = 1 [ 60.936011] [dead000000000108] address between user and kernel address ranges [ 60.943136] Internal error: Oops: 96000044 [#1] PREEMPT SMP [ 60.948691] Modules linked in: g_mass_storage(-) usb_f_mass_storage libcomposite xhci_plat_hcd xhci_hcd usbcore ti_am335x_adc kfifo_buf omap_rng cdns3 rng_core udc_core crc32_ce xfrm_user crct10dif_ce snd_so6 [ 60.993995] Process modprobe (pid: 834, stack limit = 0x00000000c2aebc69) [ 61.000765] CPU: 0 PID: 834 Comm: modprobe Not tainted 4.19.59-01963-g065f42a60499 #92 [ 61.008658] Hardware name: Texas Instruments SoC (DT) [ 61.014472] pstate: 60000005 (nZCv daif -PAN -UAO) [ 61.019253] pc : usb_gadget_unregister_driver+0x7c/0x108 [udc_core] [ 61.025503] lr : usb_gadget_unregister_driver+0x30/0x108 [udc_core] [ 61.031750] sp : ffff00001338fda0 [ 61.035049] x29: ffff00001338fda0 x28: ffff800846d40000 [ 61.040346] x27: 0000000000000000 x26: 0000000000000000 [ 61.045642] x25: 0000000056000000 x24: 0000000000000800 [ 61.050938] x23: ffff000008d7b0d0 x22: ffff0000088b07c8 [ 61.056234] x21: ffff000001100000 x20: ffff000002020260 [ 61.061530] x19: ffff0000010ffd28 x18: 0000000000000000 [ 61.066825] x17: 0000000000000000 x16: 0000000000000000 [ 61.072121] x15: 0000000000000000 x14: 0000000000000000 [ 61.077417] x13: ffff000000000000 x12: ffffffffffffffff [ 61.082712] x11: 0000000000000030 x10: 7f7f7f7f7f7f7f7f [ 61.088008] x9 : fefefefefefefeff x8 : 0000000000000000 [ 61.093304] x7 : ffffffffffffffff x6 : 000000000000ffff [ 61.098599] x5 : 8080000000000000 x4 : 0000000000000000 [ 61.103895] x3 : ffff000001100020 x2 : ffff800846d40000 [ 61.109190] x1 : dead000000000100 x0 : dead000000000200 [ 61.114486] Call trace: [ 61.116922] usb_gadget_unregister_driver+0x7c/0x108 [udc_core] [ 61.122828] usb_composite_unregister+0x10/0x18 [libcomposite] [ 61.128643] msg_cleanup+0x18/0xfce0 [g_mass_storage] [ 61.133682] __arm64_sys_delete_module+0x17c/0x1f0 [ 61.138458] el0_svc_common+0x90/0x158 [ 61.142192] el0_svc_handler+0x2c/0x80 [ 61.145926] el0_svc+0x8/0xc [ 61.148794] Code: eb03003f d10be033 54ffff21 a94d0281 (f9000420) [ 61.154869] ---[ end trace afb22e9b637bd9a7 ]--- Segmentation fault Signed-off-by: Roger Quadros --- Changelog: v2 - Retain policy behaviour if pending gadget driver fails to bind. drivers/usb/gadget/udc/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 7cf34beb50df..92af8dc98c3d 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1143,7 +1143,7 @@ static int check_pending_gadget_drivers(struct usb_udc *udc) dev_name(&udc->dev)) == 0) { ret = udc_bind_to_driver(udc, driver); if (ret != -EPROBE_DEFER) - list_del(&driver->pending); + list_del_init(&driver->pending); break; }