From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07263C7EE2F for ; Sun, 26 Feb 2023 14:48:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230015AbjBZOsY (ORCPT ); Sun, 26 Feb 2023 09:48:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229939AbjBZOsF (ORCPT ); Sun, 26 Feb 2023 09:48:05 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAD031350D; Sun, 26 Feb 2023 06:47:30 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3E7BFB80BFE; Sun, 26 Feb 2023 14:46:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0FB3BC433D2; Sun, 26 Feb 2023 14:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677422808; bh=Ov297IfQkyRAzBny+6tsDT3S7ysVEojlYlRPxBhLAF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sOH0rt9s4Vl3P4BEJrpt5ByFSm6D6XoVx2HunZ5727XFu1WrICzOVmg7DVbdDEQ8N j+AWIvP6XJZx9Xmb5SQ2n7RI6VwRnaZiKSPWBSJ5lD7/bqWHK6Y79W7S1bM6yYL7NO bt+d+VGIcHiAcKZB69fo0kCyDg7QfCTIYNz/7zSgBoBPRXbnAS7t0v13V1kSRpytV0 gFPq/XvnOF2vIIBxNrCXtWYCYrjY/xrsZhK38KqKrFNA1vq8YRKHBVq0fkMCCBHoxD 6uLoUtL5hQEJWU3jKVP46aIQWuzWH5VUP8y2NJZ9x8YI3pJYFYrJ4T7SwtHY6h6g2w Cu4F2+x5pC/jw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Kees Cook , "David S . Miller" , Sasha Levin , kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 6.2 53/53] scm: add user copy checks to put_cmsg() Date: Sun, 26 Feb 2023 09:44:45 -0500 Message-Id: <20230226144446.824580-53-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230226144446.824580-1-sashal@kernel.org> References: <20230226144446.824580-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Eric Dumazet [ Upstream commit 5f1eb1ff58ea122e24adf0bc940f268ed2227462 ] This is a followup of commit 2558b8039d05 ("net: use a bounce buffer for copying skb->mark") x86 and powerpc define user_access_begin, meaning that they are not able to perform user copy checks when using user_write_access_begin() / unsafe_copy_to_user() and friends [1] Instead of waiting bugs to trigger on other arches, add a check_object_size() in put_cmsg() to make sure that new code tested on x86 with CONFIG_HARDENED_USERCOPY=y will perform more security checks. [1] We can not generically call check_object_size() from unsafe_copy_to_user() because UACCESS is enabled at this point. Signed-off-by: Eric Dumazet Cc: Kees Cook Acked-by: Kees Cook Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/scm.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/core/scm.c b/net/core/scm.c index 5c356f0dee30c..acb7d776fa6ec 100644 --- a/net/core/scm.c +++ b/net/core/scm.c @@ -229,6 +229,8 @@ int put_cmsg(struct msghdr * msg, int level, int type, int len, void *data) if (msg->msg_control_is_user) { struct cmsghdr __user *cm = msg->msg_control_user; + check_object_size(data, cmlen - sizeof(*cm), true); + if (!user_write_access_begin(cm, cmlen)) goto efault; -- 2.39.0