From patchwork Mon May 1 18:22:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alan Stern X-Patchwork-Id: 678328 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF504C77B73 for ; Mon, 1 May 2023 18:22:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232172AbjEASWj (ORCPT ); Mon, 1 May 2023 14:22:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232178AbjEASWi (ORCPT ); Mon, 1 May 2023 14:22:38 -0400 Received: from netrider.rowland.org (netrider.rowland.org [192.131.102.5]) by lindbergh.monkeyblade.net (Postfix) with SMTP id EC7B913A for ; Mon, 1 May 2023 11:22:35 -0700 (PDT) Received: (qmail 312068 invoked by uid 1000); 1 May 2023 14:22:35 -0400 Date: Mon, 1 May 2023 14:22:35 -0400 From: Alan Stern To: Greg KH Cc: USB mailing list , syzkaller-bugs@googlegroups.com Subject: [PATCH] USB: usbtmc: Fix direction for 0-length ioctl control messages Message-ID: References: <38c0a2fd-cd9c-43b3-99f0-4f9ed2fdc69f@rowland.harvard.edu> <0000000000004b903305faa3ad0c@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <0000000000004b903305faa3ad0c@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org The syzbot fuzzer found a problem in the usbtmc driver: When a user submits an ioctl for a 0-length control transfer, the driver does not check that the direction is set to OUT: ------------[ cut here ]------------ usb 3-1: BOGUS control dir, pipe 80000b80 doesn't match bRequestType fd WARNING: CPU: 0 PID: 5100 at drivers/usb/core/urb.c:411 usb_submit_urb+0x14a7/0x1880 drivers/usb/core/urb.c:411 Modules linked in: CPU: 0 PID: 5100 Comm: syz-executor428 Not tainted 6.3.0-syzkaller-12049-g58390c8ce1bd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:usb_submit_urb+0x14a7/0x1880 drivers/usb/core/urb.c:411 Code: 7c 24 40 e8 1b 13 5c fb 48 8b 7c 24 40 e8 21 1d f0 fe 45 89 e8 44 89 f1 4c 89 e2 48 89 c6 48 c7 c7 e0 b5 fc 8a e8 19 c8 23 fb <0f> 0b e9 9f ee ff ff e8 ed 12 5c fb 0f b6 1d 12 8a 3c 08 31 ff 41 RSP: 0018:ffffc90003d2fb00 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8880789e9058 RCX: 0000000000000000 RDX: ffff888029593b80 RSI: ffffffff814c1447 RDI: 0000000000000001 RBP: ffff88801ea742f8 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff88802915e528 R13: 00000000000000fd R14: 0000000080000b80 R15: ffff8880222b3100 FS: 0000555556ca63c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ef4d18150 CR3: 0000000073e5b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: usb_start_wait_urb+0x101/0x4b0 drivers/usb/core/message.c:58 usb_internal_control_msg drivers/usb/core/message.c:102 [inline] usb_control_msg+0x320/0x4a0 drivers/usb/core/message.c:153 usbtmc_ioctl_request drivers/usb/class/usbtmc.c:1954 [inline] usbtmc_ioctl+0x1b3d/0x2840 drivers/usb/class/usbtmc.c:2097 To fix this, we must override the direction in the bRequestType field of the control request structure when the length is 0. Reported-and-tested-by: syzbot+ce77725b89b7bd52425c@syzkaller.appspotmail.com Signed-off-by: Alan Stern Link: https://lore.kernel.org/linux-usb/000000000000716a3705f9adb8ee@google.com/ CC: --- drivers/usb/class/usbtmc.c | 2 ++ 1 file changed, 2 insertions(+) Index: usb-devel/drivers/usb/class/usbtmc.c =================================================================== --- usb-devel.orig/drivers/usb/class/usbtmc.c +++ usb-devel/drivers/usb/class/usbtmc.c @@ -1928,6 +1928,8 @@ static int usbtmc_ioctl_request(struct u if (request.req.wLength > USBTMC_BUFSIZE) return -EMSGSIZE; + if (request.req.wLength == 0) /* Length-0 requests are never IN */ + request.req.bRequestType &= ~USB_DIR_IN; is_in = request.req.bRequestType & USB_DIR_IN;