From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:34702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727569AbeJKXF7 (ORCPT ); Thu, 11 Oct 2018 19:05:59 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Neukum , syzbot+843efa30c8821bd69f53@syzkaller.appspotmail.com Subject: [PATCH 3.18 057/120] USB: usbdevfs: sanitize flags more Date: Thu, 11 Oct 2018 17:33:58 +0200 Message-Id: <20181011152552.109242797@linuxfoundation.org> In-Reply-To: <20181011152549.500488630@linuxfoundation.org> References: <20181011152549.500488630@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Neukum commit 7a68d9fb851012829c29e770621905529bd9490b upstream. Requesting a ZERO_PACKET or not is sensible only for output. In the input direction the device decides. Likewise accepting short packets makes sense only for input. This allows operation with panic_on_warn without opening up a local DOS. Signed-off-by: Oliver Neukum Reported-by: syzbot+843efa30c8821bd69f53@syzkaller.appspotmail.com Fixes: 0cb54a3e47cb ("USB: debugging code shouldn't alter control flow") Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -1286,10 +1286,13 @@ static int proc_do_submiturb(struct usb_ struct async *as = NULL; struct usb_ctrlrequest *dr = NULL; unsigned int u, totlen, isofrmlen; - int i, ret, is_in, num_sgs = 0, ifnum = -1; + int i, ret, num_sgs = 0, ifnum = -1; int number_of_packets = 0; unsigned int stream_id = 0; void *buf; + bool is_in; + bool allow_short = false; + bool allow_zero = false; unsigned long mask = USBDEVFS_URB_SHORT_NOT_OK | USBDEVFS_URB_BULK_CONTINUATION | USBDEVFS_URB_NO_FSBR | @@ -1323,6 +1326,8 @@ static int proc_do_submiturb(struct usb_ u = 0; switch(uurb->type) { case USBDEVFS_URB_TYPE_CONTROL: + if (is_in) + allow_short = true; if (!usb_endpoint_xfer_control(&ep->desc)) return -EINVAL; /* min 8 byte setup packet */ @@ -1363,6 +1368,10 @@ static int proc_do_submiturb(struct usb_ break; case USBDEVFS_URB_TYPE_BULK: + if (!is_in) + allow_zero = true; + else + allow_short = true; switch (usb_endpoint_type(&ep->desc)) { case USB_ENDPOINT_XFER_CONTROL: case USB_ENDPOINT_XFER_ISOC: @@ -1383,6 +1392,10 @@ static int proc_do_submiturb(struct usb_ if (!usb_endpoint_xfer_int(&ep->desc)) return -EINVAL; interrupt_urb: + if (!is_in) + allow_zero = true; + else + allow_short = true; break; case USBDEVFS_URB_TYPE_ISO: @@ -1508,11 +1521,11 @@ static int proc_do_submiturb(struct usb_ u = (is_in ? URB_DIR_IN : URB_DIR_OUT); if (uurb->flags & USBDEVFS_URB_ISO_ASAP) u |= URB_ISO_ASAP; - if (uurb->flags & USBDEVFS_URB_SHORT_NOT_OK && is_in) + if (allow_short && uurb->flags & USBDEVFS_URB_SHORT_NOT_OK) u |= URB_SHORT_NOT_OK; if (uurb->flags & USBDEVFS_URB_NO_FSBR) u |= URB_NO_FSBR; - if (uurb->flags & USBDEVFS_URB_ZERO_PACKET) + if (allow_zero && uurb->flags & USBDEVFS_URB_ZERO_PACKET) u |= URB_ZERO_PACKET; if (uurb->flags & USBDEVFS_URB_NO_INTERRUPT) u |= URB_NO_INTERRUPT;