From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 A3B8947B436; Sat, 12 Sep 2026 18:22:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789237347; cv=none; b=Xr+NYAvNvzahTfotPV0fgAkeWKlaNlzNlvzJLh8O3n5SSzC4KSrci3qiRG72u9ahK6AgAGVC/poyw2BSDWNJ745T2X83/Wv48b3cmh4trBM6MDT079PdhX/YECmIrMhyuScK+7s+USVqZb+CLdYGgbi/sKiIgvS1dx0CZu3ugic= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789237347; c=relaxed/simple; bh=DYTDI++9u7dzYRpAxA89c7WYfGExeJLK+qA6qalqEl0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SN5QhExCKV1c1yVJQNY5X/69Y7aAFHxDnxo3MRFXeHaCRVm6oIEq9NQNGKt4Nqa0oEUTJd+g6a8iMZ6i16ci6z89dmlH+ozU6oHz58TMZH4XY4VGw8R/Wab47Eu1HuanArDXnXkv48CRQWUcoKpOchqpuddnoWkX7eH4bpekYkY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Ya6LU+IR; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Ya6LU+IR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42E5D1F000FF; Sat, 12 Sep 2026 18:22:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789237346; bh=7KHvv3jVI97cmZgBHOkNy8oU8b++J68qCEug588fzWo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Ya6LU+IRK9bHfE9vQCy3zidvqQvghfUvwa5y3XtRFZISrG6cfJUuiraJpIN0mEjk1 NWt+8slTz7lEOHMSAOI0pvzVABiNn3VZ49t5oS5+MIhf1aRPekvlL7esBU0mPhRUuI ez4bMML2Ei/xjXWD2c5819CU071lTiVmtFJFNFCg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jameson Thies , Benson Leung Subject: [PATCH 5.15 240/935] usb: typec: ucsi: displayport: Fix OOB altmode array index Date: Sat, 12 Sep 2026 08:54:30 +0200 Message-ID: <20260912065532.329877645@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jameson Thies commit 04cec690b1fd9d1c4c314b91a10d8c68a3acfe18 upstream. The UCSI displayport driver indexes the connector's port altmode array with the GET_CURRENT_CAM response after checking it is not 0xff. The port altmode array is UCSI_MAX_ALTMODES elements long. If the PPM returns an invalid GET_CURRENT_CAM response above UCSI_MAX_ALTMODES and not equal to 0xff, the kernel may crash with an array index OOB error. Update the UCSI displayport driver to verify the current cam is less than UCSI_MAX_ALTMODES before accessing the port altmode array. Fixes: af8622f6a585 ("usb: typec: ucsi: Support for DisplayPort alt mode") Cc: stable@vger.kernel.org Signed-off-by: Jameson Thies Reviewed-by: Benson Leung Link: https://patch.msgid.link/20260825234545.2076049-1-jthies@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/displayport.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/typec/ucsi/displayport.c +++ b/drivers/usb/typec/ucsi/displayport.c @@ -74,7 +74,7 @@ static int ucsi_displayport_enter(struct cur = 0xff; } - if (cur != 0xff) { + if (cur < UCSI_MAX_ALTMODES) { ret = dp->con->port_altmode[cur] == alt ? 0 : -EBUSY; goto err_unlock; }