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=-19.2 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,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 D9DCEC47082 for ; Mon, 7 Jun 2021 16:30:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C46A261C81 for ; Mon, 7 Jun 2021 16:30:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233163AbhFGQbv (ORCPT ); Mon, 7 Jun 2021 12:31:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:60366 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232468AbhFGQWq (ORCPT ); Mon, 7 Jun 2021 12:22:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id ADD59613D5; Mon, 7 Jun 2021 16:15:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623082523; bh=udkCOC6Hz1MXtaCm4KFABL+LowYHouaHndMAfGaCQBo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lm7LR2ia65hgwyU/3gqEhoa6ltwAG7nbBoAS7ptgld1aEoq/dLK3Z4xSVblVIODA5 9vol8QMUyBOcFeYdbKXl+u+gFz4aSWUfqNTBN0sb5TyeYJc26pYmzO+NsWxjP/twj1 9R6aN6rnEU7Z0SJzhaHTbDoScdDizPDaJsgkeGOueO4seBQirYIPTbl4smH9aPpQNj Mi7r9mRcfa1+sQ3akeOL7xf5SzJ3LIoyayZ/YRhThhkid48N6bcoKMK876fAwJZuwV VaNQOUs/IlsT0bTQ5bmPQD2K3hWQZb9uievZWeCF4ASmtx5YQ/Qs8qVz6K1cJc4C/4 txRmmCIvWdsZQ== 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 , linux-usb@vger.kernel.org, linux-input@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 04/18] HID: usbhid: fix info leak in hid_submit_ctrl Date: Mon, 7 Jun 2021 12:15:02 -0400 Message-Id: <20210607161517.3584577-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210607161517.3584577-1-sashal@kernel.org> References: <20210607161517.3584577-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 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