linux-kernel - [PATCH 5.4 23/71] ALSA: usb-audio: Validate MS endpoint descriptors

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210524152327.216071018@linuxfoundation.org>
Date:   Mon, 24 May 2021 17:25:29 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        syzbot+6bb23a5d5548b93c94aa@...kaller.appspotmail.com,
        Takashi Iwai <tiwai@...e.de>
Subject: [PATCH 5.4 23/71] ALSA: usb-audio: Validate MS endpoint descriptors

From: Takashi Iwai <tiwai@...e.de>

commit e84749a78dc82bc545f12ce009e3dbcc2c5a8a91 upstream.

snd_usbmidi_get_ms_info() may access beyond the border when a
malformed descriptor is passed.  This patch adds the sanity checks of
the given MS endpoint descriptors, and skips invalid ones.

Reported-by: syzbot+6bb23a5d5548b93c94aa@...kaller.appspotmail.com
Cc: <stable@...r.kernel.org>
Link: https://lore.kernel.org/r/20210510150659.17710-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@...e.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 sound/usb/midi.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/sound/usb/midi.c
+++ b/sound/usb/midi.c
@@ -1889,8 +1889,12 @@ static int snd_usbmidi_get_ms_info(struc
 		ms_ep = find_usb_ms_endpoint_descriptor(hostep);
 		if (!ms_ep)
 			continue;
+		if (ms_ep->bLength <= sizeof(*ms_ep))
+			continue;
 		if (ms_ep->bNumEmbMIDIJack > 0x10)
 			continue;
+		if (ms_ep->bLength < sizeof(*ms_ep) + ms_ep->bNumEmbMIDIJack)
+			continue;
 		if (usb_endpoint_dir_out(ep)) {
 			if (endpoints[epidx].out_ep) {
 				if (++epidx >= MIDI_MAX_ENDPOINTS) {