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=-18.9 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=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 09636C48BE5 for ; Wed, 16 Jun 2021 15:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EAEF4613C7 for ; Wed, 16 Jun 2021 15:35:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234993AbhFPPh7 (ORCPT ); Wed, 16 Jun 2021 11:37:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:50126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234861AbhFPPhN (ORCPT ); Wed, 16 Jun 2021 11:37:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4133D61356; Wed, 16 Jun 2021 15:35:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623857706; bh=Bfy/OINFM5FnQ3Zw0Dk8XG8bs8VbMfZ25+MGvtsyTXk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=e2p1Wp/DCDGIAQ3QfpZ3mvVFhbHgDBfh2tOWlsrUsBE26I1ZCBDU30/3fGwTod0w7 yKEpzVUiCgec8xMKmSmxM8od027W/PdefZ0gNXWPMdaBXdzioWOvmd8nG9YPNwlnP+ B81dfac21XYL17V1C6fnpZGtBuY5YjmnbZD+gbuQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+7c2bb71996f95a82524c@syzkaller.appspotmail.com, Anirudh Rayabharam , Benjamin Tissoires , Jiri Kosina , Sasha Levin Subject: [PATCH 5.4 08/28] HID: usbhid: fix info leak in hid_submit_ctrl Date: Wed, 16 Jun 2021 17:33:19 +0200 Message-Id: <20210616152834.415501842@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210616152834.149064097@linuxfoundation.org> References: <20210616152834.149064097@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: Anirudh Rayabharam [ Upstream commit 6be388f4a35d2ce5ef7dbf635a8964a5da7f799f ] In hid_submit_ctrl(), the way of calculating the report length doesn't take into account that report->size can be zero. When running the syzkaller reproducer, a report of size 0 causes hid_submit_ctrl) to calculate transfer_buffer_length as 16384. When this urb is passed to the usb core layer, KMSAN reports an info leak of 16384 bytes. To fix this, first modify hid_report_len() to account for the zero report size case by using DIV_ROUND_UP for the division. Then, call it from hid_submit_ctrl(). Reported-by: syzbot+7c2bb71996f95a82524c@syzkaller.appspotmail.com Signed-off-by: Anirudh Rayabharam Acked-by: Benjamin Tissoires Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/usbhid/hid-core.c | 2 +- include/linux/hid.h | 3 +-- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index 17a638f15082..1cfbbaf6901d 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -374,7 +374,7 @@ static int hid_submit_ctrl(struct hid_device *hid) raw_report = usbhid->ctrl[usbhid->ctrltail].raw_report; dir = usbhid->ctrl[usbhid->ctrltail].dir; - len = ((report->size - 1) >> 3) + 1 + (report->id > 0); + len = hid_report_len(report); if (dir == USB_DIR_OUT) { usbhid->urbctrl->pipe = usb_sndctrlpipe(hid_to_usb_dev(hid), 0); usbhid->urbctrl->transfer_buffer_length = len; diff --git a/include/linux/hid.h b/include/linux/hid.h index ae906deb42e8..85bedeb9ca9f 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -1154,8 +1154,7 @@ static inline void hid_hw_wait(struct hid_device *hdev) */ static inline u32 hid_report_len(struct hid_report *report) { - /* equivalent to DIV_ROUND_UP(report->size, 8) + !!(report->id > 0) */ - return ((report->size - 1) >> 3) + 1 + (report->id > 0); + return DIV_ROUND_UP(report->size, 8) + (report->id > 0); } int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size, -- 2.30.2