diff options
| author | Oliver Neukum <oneukum@suse.com> | 2018-09-05 12:07:02 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-20 12:48:39 +0200 |
| commit | 7a68d9fb851012829c29e770621905529bd9490b (patch) | |
| tree | d46548b2c14c362c18dd6a0bafb6363553ff565d /drivers/usb | |
| parent | e871db8d78df1c411032cbb3acfdf8930509360e (diff) | |
| download | linux-7a68d9fb851012829c29e770621905529bd9490b.tar.gz | |
USB: usbdevfs: sanitize flags more
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 <oneukum@suse.com>
Reported-by: syzbot+843efa30c8821bd69f53@syzkaller.appspotmail.com
Fixes: 0cb54a3e47cb ("USB: debugging code shouldn't alter control flow")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/core/devio.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 6ce77b33da61..263dd2f309fb 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -1434,10 +1434,13 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb 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 | @@ -1471,6 +1474,8 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb 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 */ @@ -1511,6 +1516,10 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb 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: @@ -1531,6 +1540,10 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb 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: @@ -1676,9 +1689,9 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb 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_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; |