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| author | Dan Carpenter <dan.carpenter@oracle.com> | 2017-09-22 20:43:46 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-12 09:51:17 (GMT) |
| commit | 77a4be89599c587f8b1ac6256ad7dc11a8ce28fa (patch) | |
| tree | 8e4d0848360b44554692990030eb4f7570a43dd4 /drivers/usb | |
| parent | e39b17143a5b5aac81f066d455e5d3a9877eb3ae (diff) | |
| download | linux-77a4be89599c587f8b1ac6256ad7dc11a8ce28fa.tar.xz | |
USB: devio: Don't corrupt user memory
commit fa1ed74eb1c233be6131ec92df21ab46499a15b6 upstream.
The user buffer has "uurb->buffer_length" bytes. If the kernel has more
information than that, we should truncate it instead of writing past
the end of the user's buffer. I added a WARN_ONCE() to help the user
debug the issue.
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/core/devio.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index c8075eb..860108c 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -1577,7 +1577,11 @@ static int proc_do_submiturb(struct usb_dev_state *ps, struct usbdevfs_urb *uurb totlen += isopkt[u].length; } u *= sizeof(struct usb_iso_packet_descriptor); - uurb->buffer_length = totlen; + if (totlen <= uurb->buffer_length) + uurb->buffer_length = totlen; + else + WARN_ONCE(1, "uurb->buffer_length is too short %d vs %d", + totlen, uurb->buffer_length); break; default: |