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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 66578C2B9F4 for ; Mon, 28 Jun 2021 14:47:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47D2E619AD for ; Mon, 28 Jun 2021 14:47:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234702AbhF1OuU (ORCPT ); Mon, 28 Jun 2021 10:50:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:54506 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236320AbhF1OrU (ORCPT ); Mon, 28 Jun 2021 10:47:20 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D1C9661CA3; Mon, 28 Jun 2021 14:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624890994; bh=udkCOC6Hz1MXtaCm4KFABL+LowYHouaHndMAfGaCQBo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tgjIFMWNZr/Mtq6eRZ4q5TgjHBRBlthkYmUkKBvXpXinXm951qzv8m9xwddXb17ST nx9atkTlZt1n5llnidI9VCWyvcBJ5RqNov84dQlja4Op8PafkoG5Bdp2ZMpTfOx3G9 /EuB0Qn86oBcJVDz1aPQbnehQ0vXAmLxOvESZ8eG2hWb8/nvWfB126BP9prQxEPD04 ONDd35/+CS1w1LrUaqA8gwG3cWhudRDg6xJPIAqORbctq3GUiXWV2KHH0v0l7pF2H3 XOOFRHpmIRwxNaTFb4LYRi2hU+nqTCLRDlDQmEG7xMRdP81BDhBdVnpViopTZJhdcw 7pzrvBiagpf+Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Anirudh Rayabharam , syzbot+7c2bb71996f95a82524c@syzkaller.appspotmail.com, Benjamin Tissoires , Jiri Kosina , Sasha Levin Subject: [PATCH 4.14 04/88] HID: usbhid: fix info leak in hid_submit_ctrl Date: Mon, 28 Jun 2021 10:35:04 -0400 Message-Id: <20210628143628.33342-5-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210628143628.33342-1-sashal@kernel.org> References: <20210628143628.33342-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.14.238-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.14.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.14.238-rc1 X-KernelTest-Deadline: 2021-06-30T14:36+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@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 98916fb4191a..46b8f4c353de 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -373,7 +373,7 @@ 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 d07fe33a9045..5a2c55ed33fa 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -1114,8 +1114,7 @@ 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