Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933223AbcDKNof (ORCPT ); Mon, 11 Apr 2016 09:44:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:37473 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932461AbcDKNYH (ORCPT ); Mon, 11 Apr 2016 09:24:07 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Takashi Iwai , Jiri Slaby Subject: [PATCH 3.12 59/98] ALSA: usb-audio: Add sanity checks for endpoint accesses Date: Mon, 11 Apr 2016 15:23:01 +0200 Message-Id: X-Mailer: git-send-email 2.8.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2828 Lines: 82 From: Takashi Iwai 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 447d6275f0c21f6cc97a88b3a0c601436a4cdf2a upstream. Add some sanity check codes before actually accessing the endpoint via get_endpoint() in order to avoid the invalid access through a malformed USB descriptor. Mostly just checking bNumEndpoints, but in one place (snd_microii_spdif_default_get()), the validity of iface and altsetting index is checked as well. Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=971125 Signed-off-by: Takashi Iwai Signed-off-by: Jiri Slaby --- sound/usb/clock.c | 2 ++ sound/usb/endpoint.c | 3 +++ sound/usb/mixer_quirks.c | 4 ++++ sound/usb/pcm.c | 2 ++ 4 files changed, 11 insertions(+) diff --git a/sound/usb/clock.c b/sound/usb/clock.c index 86f80c60b21f..1329d7725196 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -283,6 +283,8 @@ static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface, unsigned char data[3]; int err, crate; + if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress; /* if endpoint doesn't have sampling rate control, bail out */ diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index b0a0f2028319..c42a4c0e95da 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -410,6 +410,9 @@ exit_clear: * * New endpoints will be added to chip->ep_list and must be freed by * calling snd_usb_endpoint_free(). + * + * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that + * bNumEndpoints > 1 beforehand. */ struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, struct usb_host_interface *alts, diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c index ca2d07378807..ee4b3b901bf5 100644 --- a/sound/usb/mixer_quirks.c +++ b/sound/usb/mixer_quirks.c @@ -1372,7 +1372,11 @@ static int snd_microii_spdif_default_get(struct snd_kcontrol *kcontrol, /* use known values for that card: interface#1 altsetting#1 */ iface = usb_ifnum_to_if(mixer->chip->dev, 1); + if (!iface || iface->num_altsetting < 2) + return -EINVAL; alts = &iface->altsetting[1]; + if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress; err = snd_usb_ctl_msg(mixer->chip->dev, diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 98ca3540514f..1f498b1f88bd 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -159,6 +159,8 @@ static int init_pitch_v1(struct snd_usb_audio *chip, int iface, unsigned char data[1]; int err; + if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress; data[0] = 1; -- 2.8.1