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 849F6259CBB; Mon, 1 Dec 2025 11:32:12 +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=1764588732; cv=none; b=p2GeH2zfHijakzPSgF/xKsvDevtibl7c/CJaO8M2wSNNLHNTxiYnXccnr2JXn0McOvLutYB2zIxam7CI8HIUIF+lG97FqjnBSihUBWchUTi2xcNtYlaFccI0AWnkFes8RZy9dIqAETcsp3LfJKLkwgaak/XMyIi7iPL+JbymUQ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764588732; c=relaxed/simple; bh=FaTD6hsNAsWWNvN8M+pkeTYcBWMSzL9mnwc5PxYOoc8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Is9PsEreLrj5KVl553S9AAcWA8BBZYvxQGD4wObRRzd04hUv3NlFPwg1br1/ekmXOZhaWeC/+HTQykOPJq6zAWoP+X3YdMP8fmJunEPH3rB47YbDuqqrOjYCM51JqsqIXVFWys4PAsl5WmnztF1Z5K1pnQPzao7CCe9W/3RKv5U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NdQ8n29r; 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="NdQ8n29r" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00408C4CEF1; Mon, 1 Dec 2025 11:32:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764588732; bh=FaTD6hsNAsWWNvN8M+pkeTYcBWMSzL9mnwc5PxYOoc8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NdQ8n29rkOyTKgUXKoRqmZnZtXiB+s9nZkbWOmxwA2y9rCZkc0qYWW+pb+0J+z2qf 3skzvegihYKsrDg47d7g6y5yezS6Zc+P3PAye+yjDD5b6xLxyt6kIBPSvZnuOFAogT 4nQpjrYEKgC0wZkshGo/1eCemmWLLy2RT37fVlRo= 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 5.4 150/187] ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd Date: Mon, 1 Dec 2025 12:24:18 +0100 Message-ID: <20251201112246.637317243@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251201112241.242614045@linuxfoundation.org> References: <20251201112241.242614045@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 5.4-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 f2c697ff50b57..11a74cc0e94d8 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -2967,6 +2967,8 @@ 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