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=-24.4 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,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 99F66C4320E for ; Fri, 13 Aug 2021 15:13:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80CC8610CF for ; Fri, 13 Aug 2021 15:13:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242071AbhHMPN1 (ORCPT ); Fri, 13 Aug 2021 11:13:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:53104 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241806AbhHMPLn (ORCPT ); Fri, 13 Aug 2021 11:11:43 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E8F99610FE; Fri, 13 Aug 2021 15:11:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628867476; bh=30KxOoloYmk5zGptQQfwJlpzpjCtuvoyUMdhH9lZjGY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=16OLWzmKS1kHlI3+Iw1b5R+pKtNl2EVoda17Wie8FFHesvhsh9CqvCcAM5IWO9nJe FEHVK44F04sMAI+HUHC1dfikCNNKzMBDDJGyMmMzGBYXVinza4vOUmkIrZbzyNCLMo BHjW62eX2sxO7ym065Tqn+NOvyX95184/E8jJf6k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Maxim Devaev , Phil Elwell Subject: [PATCH 4.14 20/42] usb: gadget: f_hid: fixed NULL pointer dereference Date: Fri, 13 Aug 2021 17:06:46 +0200 Message-Id: <20210813150525.780787054@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210813150525.098817398@linuxfoundation.org> References: <20210813150525.098817398@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Phil Elwell commit 2867652e4766360adf14dfda3832455e04964f2a upstream. Disconnecting and reconnecting the USB cable can lead to crashes and a variety of kernel log spam. The problem was found and reproduced on the Raspberry Pi [1] and the original fix was created in Raspberry's own fork [2]. Link: https://github.com/raspberrypi/linux/issues/3870 [1] Link: https://github.com/raspberrypi/linux/commit/a6e47d5f4efbd2ea6a0b6565cd2f9b7bb217ded5 [2] Signed-off-by: Maxim Devaev Signed-off-by: Phil Elwell Cc: stable Link: https://lore.kernel.org/r/20210723155928.210019-1-mdevaev@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_hid.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -349,6 +349,11 @@ static ssize_t f_hidg_write(struct file spin_lock_irqsave(&hidg->write_spinlock, flags); + if (!hidg->req) { + spin_unlock_irqrestore(&hidg->write_spinlock, flags); + return -ESHUTDOWN; + } + #define WRITE_COND (!hidg->write_pending) try_again: /* write queue */ @@ -369,8 +374,14 @@ try_again: count = min_t(unsigned, count, hidg->report_length); spin_unlock_irqrestore(&hidg->write_spinlock, flags); - status = copy_from_user(req->buf, buffer, count); + if (!req) { + ERROR(hidg->func.config->cdev, "hidg->req is NULL\n"); + status = -ESHUTDOWN; + goto release_write_pending; + } + + status = copy_from_user(req->buf, buffer, count); if (status != 0) { ERROR(hidg->func.config->cdev, "copy_from_user error\n"); @@ -398,14 +409,17 @@ try_again: spin_unlock_irqrestore(&hidg->write_spinlock, flags); + if (!hidg->in_ep->enabled) { + ERROR(hidg->func.config->cdev, "in_ep is disabled\n"); + status = -ESHUTDOWN; + goto release_write_pending; + } + status = usb_ep_queue(hidg->in_ep, req, GFP_ATOMIC); - if (status < 0) { - ERROR(hidg->func.config->cdev, - "usb_ep_queue error on int endpoint %zd\n", status); + if (status < 0) goto release_write_pending; - } else { + else status = count; - } return status; release_write_pending: