usb-mtp: outlaw slashes in filenames

Slash is unix directory separator, so they are not allowed in filenames.
Note this also stops the classic escape via "../".

Fixes: CVE-2018-16867
Reported-by: Michael Hanselmann <public@hansmi.ch>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20181203101045.27976-3-kraxel@redhat.com
This commit is contained in:
Gerd Hoffmann 2018-12-03 11:10:45 +01:00
parent 6de02a1323
commit c52d46e041

View File

@ -1719,6 +1719,12 @@ static void usb_mtp_write_metadata(MTPState *s)
filename = utf16_to_str(dataset->length, dataset->filename); filename = utf16_to_str(dataset->length, dataset->filename);
if (strchr(filename, '/')) {
usb_mtp_queue_result(s, RES_PARAMETER_NOT_SUPPORTED, d->trans,
0, 0, 0, 0);
return;
}
o = usb_mtp_object_lookup_name(p, filename, dataset->length); o = usb_mtp_object_lookup_name(p, filename, dataset->length);
if (o != NULL) { if (o != NULL) {
next_handle = o->handle; next_handle = o->handle;