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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A6D7CA9EBD for ; Sun, 27 Oct 2019 21:28:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D6962064A for ; Sun, 27 Oct 2019 21:28:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572211690; bh=gSQtZAIgBdTi7gc6F0njdzOUiSs2iuVgr2fcN/YxcWM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=h4EfMgCJ5OvosrVhph4lXSHgeKrn3jiRInbQVhnifTWMY1HbeyBTm0G4xFayAYpMs Vf0NGPFkCuEuKR3sAsjalH7gYTX4iFfFWTlqNkqouxZTkb1TyzVpE64YXoinuP0nx8 d92VTMXfvepF+yhWJtn9ZCQKceRE/1g/kh97n8I4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731692AbfJ0VXT (ORCPT ); Sun, 27 Oct 2019 17:23:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:44490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731462AbfJ0VXS (ORCPT ); Sun, 27 Oct 2019 17:23:18 -0400 Received: from localhost (100.50.158.77.rev.sfr.net [77.158.50.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 92FAC205C9; Sun, 27 Oct 2019 21:23:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572211397; bh=gSQtZAIgBdTi7gc6F0njdzOUiSs2iuVgr2fcN/YxcWM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EYMotQDkbVhrzKH/BNdRGzZgg5TvJp40rqWyFyOfjwKc+FJoLUgns9AgSpD8dKMoP zYqy99zLocVrkMJlVvt7rGw+k/Up+pDYx4MfQEK0ttge1QFHUkYnpI8gljzBSI+IuN rPAdbSwt+AmqRxhzj16vmgke/qe6OYY4XVt3W6Lc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , David Howells , "David S. Miller" , Sasha Levin Subject: [PATCH 5.3 093/197] rxrpc: use rcu protection while reading sk->sk_user_data Date: Sun, 27 Oct 2019 22:00:11 +0100 Message-Id: <20191027203356.781169462@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203351.684916567@linuxfoundation.org> References: <20191027203351.684916567@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 2ca4f6ca4562594ef161e4140c2a5e0e5282967b ] We need to extend the rcu_read_lock() section in rxrpc_error_report() and use rcu_dereference_sk_user_data() instead of plain access to sk->sk_user_data to make sure all rules are respected. The compiler wont reload sk->sk_user_data at will, and RCU rules prevent memory beeing freed too soon. Fixes: f0308fb07080 ("rxrpc: Fix possible NULL pointer access in ICMP handling") Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Signed-off-by: Eric Dumazet Cc: David Howells Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/rxrpc/peer_event.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c index 61451281d74a3..48f67a9b1037c 100644 --- a/net/rxrpc/peer_event.c +++ b/net/rxrpc/peer_event.c @@ -147,13 +147,16 @@ void rxrpc_error_report(struct sock *sk) { struct sock_exterr_skb *serr; struct sockaddr_rxrpc srx; - struct rxrpc_local *local = sk->sk_user_data; + struct rxrpc_local *local; struct rxrpc_peer *peer; struct sk_buff *skb; - if (unlikely(!local)) + rcu_read_lock(); + local = rcu_dereference_sk_user_data(sk); + if (unlikely(!local)) { + rcu_read_unlock(); return; - + } _enter("%p{%d}", sk, local->debug_id); /* Clear the outstanding error value on the socket so that it doesn't @@ -163,6 +166,7 @@ void rxrpc_error_report(struct sock *sk) skb = sock_dequeue_err_skb(sk); if (!skb) { + rcu_read_unlock(); _leave("UDP socket errqueue empty"); return; } @@ -170,11 +174,11 @@ void rxrpc_error_report(struct sock *sk) serr = SKB_EXT_ERR(skb); if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) { _leave("UDP empty message"); + rcu_read_unlock(); rxrpc_free_skb(skb, rxrpc_skb_freed); return; } - rcu_read_lock(); peer = rxrpc_lookup_peer_icmp_rcu(local, skb, &srx); if (peer && !rxrpc_get_peer_maybe(peer)) peer = NULL; -- 2.20.1