From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C1A151DE2A5; Fri, 21 Nov 2025 13:29:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763731788; cv=none; b=JYEoLgv5zq8i9xiqBp9x7cDrkmP8Vnm8q3JRhw1U8NWvlOtvY487QNfHvtleqW09KT3zGSlcXwU70nsIi9Nh9+bJmOFYqMwj6naQZ6fFIc2VOI31sk6FYPj5C12sM5CnWjBtT8EufQqHB2i8WcAS/4Ki8zXuOAu6TGl0IX3Nhvs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763731788; c=relaxed/simple; bh=I0WTAqX+HZANFtHqToLm1uFnQgkxb1hWGW+/TKjxtKU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=be5Lwq6MDOt4yqAgs26APyPnws0buEveNazdGaJPFGquEQkOh6P7YU84bPBdU7LS1gFMgDviwSeWnoXtrLQSBFFsKunN5xpPhFwK5KyYIYHe4If9aqKPK6mHrM+o2EylUtoHxvRtdmQRSFie5GukUWSoZNRy7mzewt886twNMF0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cBXs5UhU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cBXs5UhU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C814C4CEF1; Fri, 21 Nov 2025 13:29:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1763731788; bh=I0WTAqX+HZANFtHqToLm1uFnQgkxb1hWGW+/TKjxtKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cBXs5UhU9jtgloXGwh75cuawdjzbVlfDJefLuOcQ9KI+49NGTn7EAHox+D+qeruDw Qy5SSnc6vL3afdxn07WUE4nOekHd7m/dbJHVdgl8Ikp6dqZj7NcOJluOjbx5x2EKZJ HCGkiiAQfB38g4mkPwXrijEsdUKCX3lXKAZNbCzw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Haein Lee , Takashi Iwai , Sasha Levin Subject: [PATCH 6.12 080/185] ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd Date: Fri, 21 Nov 2025 14:11:47 +0100 Message-ID: <20251121130146.757781339@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251121130143.857798067@linuxfoundation.org> References: <20251121130143.857798067@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Haein Lee [ Upstream commit 632108ec072ad64c8c83db6e16a7efee29ebfb74 ] In snd_usb_create_streams(), for UAC version 3 devices, the Interface Association Descriptor (IAD) is retrieved via usb_ifnum_to_if(). If this call fails, a fallback routine attempts to obtain the IAD from the next interface and sets a BADD profile. However, snd_usb_mixer_controls_badd() assumes that the IAD retrieved from usb_ifnum_to_if() is always valid, without performing a NULL check. This can lead to a NULL pointer dereference when usb_ifnum_to_if() fails to find the interface descriptor. This patch adds a NULL pointer check after calling usb_ifnum_to_if() in snd_usb_mixer_controls_badd() to prevent the dereference. This issue was discovered by syzkaller, which triggered the bug by sending a crafted USB device descriptor. Fixes: 17156f23e93c ("ALSA: usb: add UAC3 BADD profiles support") Signed-off-by: Haein Lee Link: https://patch.msgid.link/vwhzmoba9j2f.vwhzmob9u9e2.g6@dooray.com Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/usb/mixer.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index ba9c6874915a2..4853336f0e6b5 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -3079,6 +3079,8 @@ static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer, int i; assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc; + if (!assoc) + return -EINVAL; /* Detect BADD capture/playback channels from AS EP descriptors */ for (i = 0; i < assoc->bInterfaceCount; i++) { -- 2.51.0