diff options
| author | Johan Hovold <johan@kernel.org> | 2019-10-03 15:49:58 +0200 |
|---|---|---|
| committer | Johan Hovold <johan@kernel.org> | 2019-10-04 10:57:19 +0200 |
| commit | 7d7e21fafdbc7fcf0854b877bd0975b487ed2717 (patch) | |
| tree | 05ec67c29029e7ace9d86bbb824537c640c391e5 /drivers/usb/serial/keyspan.c | |
| parent | dfbac2f4da6a0c4a8f6b4d715a4077a7b8df53ad (diff) | |
USB: serial: keyspan: fix NULL-derefs on open() and write()
Fix NULL-pointer dereferences on open() and write() which can be
triggered by a malicious USB device.
The current URB allocation helper would fail to initialise the newly
allocated URB if the device has unexpected endpoint descriptors,
something which could lead NULL-pointer dereferences in a number of
open() and write() paths when accessing the URB. For example:
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:usb_clear_halt+0x11/0xc0
...
Call Trace:
? tty_port_open+0x4d/0xd0
keyspan_open+0x70/0x160 [keyspan]
serial_port_activate+0x5b/0x80 [usbserial]
tty_port_open+0x7b/0xd0
? check_tty_count+0x43/0xa0
tty_open+0xf1/0x490
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:keyspan_write+0x14e/0x1f3 [keyspan]
...
Call Trace:
serial_write+0x43/0xa0 [usbserial]
n_tty_write+0x1af/0x4f0
? do_wait_intr_irq+0x80/0x80
? process_echoes+0x60/0x60
tty_write+0x13f/0x2f0
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:keyspan_usa26_send_setup+0x298/0x305 [keyspan]
...
Call Trace:
keyspan_open+0x10f/0x160 [keyspan]
serial_port_activate+0x5b/0x80 [usbserial]
tty_port_open+0x7b/0xd0
? check_tty_count+0x43/0xa0
tty_open+0xf1/0x490
Fixes: fdcba53e2d58 ("fix for bugzilla #7544 (keyspan USB-to-serial converter)")
Cc: stable <stable@vger.kernel.org> # 2.6.21
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial/keyspan.c')
| -rw-r--r-- | drivers/usb/serial/keyspan.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c index d34779fe4a8d..e66a59ef43a1 100644 --- a/drivers/usb/serial/keyspan.c +++ b/drivers/usb/serial/keyspan.c @@ -1741,8 +1741,8 @@ static struct urb *keyspan_setup_urb(struct usb_serial *serial, int endpoint, ep_desc = find_ep(serial, endpoint); if (!ep_desc) { - /* leak the urb, something's wrong and the callers don't care */ - return urb; + usb_free_urb(urb); + return NULL; } if (usb_endpoint_xfer_int(ep_desc)) { ep_type_name = "INT"; |