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 B7C44386C22; Sat, 12 Sep 2026 19:37:17 +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=1789241838; cv=none; b=ihtpBif9ZQB+DE0pst7K9BIH2ZHHmfYQtdv2FUUZFYq2nu3jLxW2S+3tn8Z8PhI9KcKIsy5WWKTyg+q09tIBNBYAk5s8YWDo/PnxIzaNrCjCSCfZpi6Krm7o0qaMrYbcpj1+iN2RbagsVF5muE1xW7ePHkw/P11ZtHNfmzIL/98= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789241838; c=relaxed/simple; bh=75zxqOyhna3aYQDI2YJBD4EThsYIgMwFduGtW0zISaM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=InGZTOH9wh80aKVEmMlEgFlezWOprxyTnGUE+S22GRTmU5M+kS6r54z1BNAq5W4KfA9GhcFPrsZFZTGivgXxUKSXc1dNVQ4QpUhTSe4r9TaMXCsPRoFaRztCnUr4eKms+iINNAV4hDv3DgftD1nnNQUYq5WuYDNX7syX0rfODTQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yBySJ6Dt; 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="yBySJ6Dt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BEE861F0089E; Sat, 12 Sep 2026 19:37:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789241837; bh=dgZjkVKMmuJrnk/yVAdCIuIerRKKVFCQ/Jw4AILKqew=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yBySJ6Dtg0PAg9z0kzwOSsnmA2X1IUq43MM5qwPUGtAFcBnrj65mRtIcSJMVqp12R 0pEeXRQFfpfSHXnpk17wfg839LqQbtFbGkU3x3f0e+mMWT1125SCM3XXIM33o02HB9 unek0GlseVn2k1kXPZjurzS1gXXgDQ4B07nnHzic= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jameson Thies , Benson Leung Subject: [PATCH 5.10 218/798] usb: typec: ucsi: displayport: Fix OOB altmode array index Date: Sat, 12 Sep 2026 08:57:26 +0200 Message-ID: <20260912065522.116614694@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065516.948645775@linuxfoundation.org> References: <20260912065516.948645775@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 5.10-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 @@ -72,7 +72,7 @@ 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; }