From patchwork Tue Aug 10 17:30:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 495744 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=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 4672DC4320A for ; Tue, 10 Aug 2021 18:00:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2D7106044F for ; Tue, 10 Aug 2021 18:00:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237213AbhHJSBT (ORCPT ); Tue, 10 Aug 2021 14:01:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:60118 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238063AbhHJR7R (ORCPT ); Tue, 10 Aug 2021 13:59:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 66A5561181; Tue, 10 Aug 2021 17:46:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628617573; bh=Gkv8usg/hRL6/6cAr9d4ZngDvOLRKk8GTGE5ck5X+dU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gAw7n7LH5tyQAx1YSdh7LnMNAl4mugCLa1SpP5Dz4QQR366WqYmyVv6u12e922g3l 2iVU3+j0kmMPnC+KBzXI3as7m3YmeDXYJDHdLdZB85ZkKxlpyEonvNYCTXVJmg3H9p txVdKYWjobBVJqVdDXEUsqNs0QrwMIsT5KIwqVLc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Skripkin , syzbot+5872a520e0ce0a7c7230@syzkaller.appspotmail.com, syzbot+cc699626e48a6ebaf295@syzkaller.appspotmail.com Subject: [PATCH 5.13 118/175] staging: rtl8712: error handling refactoring Date: Tue, 10 Aug 2021 19:30:26 +0200 Message-Id: <20210810173004.836493220@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210810173000.928681411@linuxfoundation.org> References: <20210810173000.928681411@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Pavel Skripkin commit e9e6aa51b2735d83a67d9fa0119cf11abef80d99 upstream. There was strange error handling logic in case of fw load failure. For some reason fw loader callback was doing clean up stuff when fw is not available. I don't see any reason behind doing this. Since this driver doesn't have EEPROM firmware let's just disconnect it in case of fw load failure. Doing clean up stuff in 2 different place which can run concurently is not good idea and syzbot found 2 bugs related to this strange approach. So, in this pacth I deleted all clean up code from fw callback and made a call to device_release_driver() under device_lock(parent) in case of fw load failure. This approach is more generic and it defend driver from UAF bugs, since all clean up code is moved to one place. Fixes: e02a3b945816 ("staging: rtl8712: fix memory leak in rtl871x_load_fw_cb") Fixes: 8c213fa59199 ("staging: r8712u: Use asynchronous firmware loading") Cc: stable Reported-and-tested-by: syzbot+5872a520e0ce0a7c7230@syzkaller.appspotmail.com Reported-and-tested-by: syzbot+cc699626e48a6ebaf295@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Link: https://lore.kernel.org/r/d49ecc56e97c4df181d7bd4d240b031f315eacc3.1626895918.git.paskripkin@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/rtl8712/hal_init.c | 30 +++++++++++++++-------- drivers/staging/rtl8712/usb_intf.c | 48 ++++++++++++++++--------------------- 2 files changed, 41 insertions(+), 37 deletions(-) --- a/drivers/staging/rtl8712/hal_init.c +++ b/drivers/staging/rtl8712/hal_init.c @@ -29,21 +29,31 @@ #define FWBUFF_ALIGN_SZ 512 #define MAX_DUMP_FWSZ (48 * 1024) +static void rtl871x_load_fw_fail(struct _adapter *adapter) +{ + struct usb_device *udev = adapter->dvobjpriv.pusbdev; + struct device *dev = &udev->dev; + struct device *parent = dev->parent; + + complete(&adapter->rtl8712_fw_ready); + + dev_err(&udev->dev, "r8712u: Firmware request failed\n"); + + if (parent) + device_lock(parent); + + device_release_driver(dev); + + if (parent) + device_unlock(parent); +} + static void rtl871x_load_fw_cb(const struct firmware *firmware, void *context) { struct _adapter *adapter = context; if (!firmware) { - struct usb_device *udev = adapter->dvobjpriv.pusbdev; - struct usb_interface *usb_intf = adapter->pusb_intf; - - dev_err(&udev->dev, "r8712u: Firmware request failed\n"); - usb_put_dev(udev); - usb_set_intfdata(usb_intf, NULL); - r8712_free_drv_sw(adapter); - adapter->dvobj_deinit(adapter); - complete(&adapter->rtl8712_fw_ready); - free_netdev(adapter->pnetdev); + rtl871x_load_fw_fail(adapter); return; } adapter->fw = firmware; --- a/drivers/staging/rtl8712/usb_intf.c +++ b/drivers/staging/rtl8712/usb_intf.c @@ -594,36 +594,30 @@ static void r871xu_dev_remove(struct usb { struct net_device *pnetdev = usb_get_intfdata(pusb_intf); struct usb_device *udev = interface_to_usbdev(pusb_intf); + struct _adapter *padapter = netdev_priv(pnetdev); - if (pnetdev) { - struct _adapter *padapter = netdev_priv(pnetdev); + /* never exit with a firmware callback pending */ + wait_for_completion(&padapter->rtl8712_fw_ready); + usb_set_intfdata(pusb_intf, NULL); + release_firmware(padapter->fw); + if (drvpriv.drv_registered) + padapter->surprise_removed = true; + if (pnetdev->reg_state != NETREG_UNINITIALIZED) + unregister_netdev(pnetdev); /* will call netdev_close() */ + r8712_flush_rwctrl_works(padapter); + r8712_flush_led_works(padapter); + udelay(1); + /* Stop driver mlme relation timer */ + r8712_stop_drv_timers(padapter); + r871x_dev_unload(padapter); + r8712_free_drv_sw(padapter); + free_netdev(pnetdev); - /* never exit with a firmware callback pending */ - wait_for_completion(&padapter->rtl8712_fw_ready); - pnetdev = usb_get_intfdata(pusb_intf); - usb_set_intfdata(pusb_intf, NULL); - if (!pnetdev) - goto firmware_load_fail; - release_firmware(padapter->fw); - if (drvpriv.drv_registered) - padapter->surprise_removed = true; - if (pnetdev->reg_state != NETREG_UNINITIALIZED) - unregister_netdev(pnetdev); /* will call netdev_close() */ - r8712_flush_rwctrl_works(padapter); - r8712_flush_led_works(padapter); - udelay(1); - /* Stop driver mlme relation timer */ - r8712_stop_drv_timers(padapter); - r871x_dev_unload(padapter); - r8712_free_drv_sw(padapter); - free_netdev(pnetdev); + /* decrease the reference count of the usb device structure + * when disconnect + */ + usb_put_dev(udev); - /* decrease the reference count of the usb device structure - * when disconnect - */ - usb_put_dev(udev); - } -firmware_load_fail: /* If we didn't unplug usb dongle and remove/insert module, driver * fails on sitesurvey for the first time when device is up. * Reset usb port for sitesurvey fail issue.