From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38208) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gTlBm-0007fv-KK for qemu-devel@nongnu.org; Mon, 03 Dec 2018 05:10:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gTlBh-0001XF-SW for qemu-devel@nongnu.org; Mon, 03 Dec 2018 05:10:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47912) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gTlBh-0001WX-NX for qemu-devel@nongnu.org; Mon, 03 Dec 2018 05:10:49 -0500 From: Gerd Hoffmann Date: Mon, 3 Dec 2018 11:10:45 +0100 Message-Id: <20181203101045.27976-3-kraxel@redhat.com> In-Reply-To: <20181203101045.27976-1-kraxel@redhat.com> References: <20181203101045.27976-1-kraxel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH for-3.1 v3 2/2] usb-mtp: outlaw slashes in filenames List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: public@hansmi.ch, Gerd Hoffmann 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 Signed-off-by: Gerd Hoffmann Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- hw/usb/dev-mtp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c index 0f6a9702ef..100b7171f4 100644 --- a/hw/usb/dev-mtp.c +++ b/hw/usb/dev-mtp.c @@ -1719,6 +1719,12 @@ static void usb_mtp_write_metadata(MTPState *s) =20 filename =3D utf16_to_str(dataset->length, dataset->filename); =20 + if (strchr(filename, '/')) { + usb_mtp_queue_result(s, RES_PARAMETER_NOT_SUPPORTED, d->trans, + 0, 0, 0, 0); + return; + } + o =3D usb_mtp_object_lookup_name(p, filename, dataset->length); if (o !=3D NULL) { next_handle =3D o->handle; --=20 2.9.3