leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

USB: devio: Don't corrupt user memory

Browse Source 
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>
Cc: stable <stable@vger.kernel.org>
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>
This commit is contained in:
Dan Carpenter 2017-09-22 23:43:46 +03:00 committed by Greg Kroah-Hartman
parent 57999d1107
commit fa1ed74eb1
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/usb/core/devio.c
View File

@ -1576,7 +1576,11 @@ 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: