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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 0F44AC47E49 for ; Sat, 26 Oct 2019 13:36:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9529214DA for ; Sat, 26 Oct 2019 13:36:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572096984; bh=i6OBQan2kKE6S0mHWye64Z4OOzcnSu3pGuUf59jIpnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Rq6e3XmI4ntbAzlQNGTEuto+zVM8A60FbRb9gKfphsFGOhRoaLZTLYlNwiIeDPhic fFEp2I8ZS0YFK5HkEbPD6Thi80G7Jx/Dykakj3TZy2QZcSKdp9mD8fa3ilpYa/TuaM HY2sjHZLPv61lOIpQzjvlBs3QcfGiD1Vo3WOwSjE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726864AbfJZNQh (ORCPT ); Sat, 26 Oct 2019 09:16:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:38110 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726805AbfJZNQd (ORCPT ); Sat, 26 Oct 2019 09:16:33 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 52572222C2; Sat, 26 Oct 2019 13:16:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572095793; bh=i6OBQan2kKE6S0mHWye64Z4OOzcnSu3pGuUf59jIpnk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2bcGXzL6cq8pZ6bVAOo8c0vufFvwq1Ikxk3/qZ1RjIFPKPMCW37yWS1lUrIoGS/rF 36gANyfgfVzm3BoBj3ULSRy786R/3QZRdz/aPjd05+ATLCQtFRS+K4ThpmNjY6ck14 9RZznq7F5yWCymqmzveYRVgve6wqBbLXgiZqQsLY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: David Howells , syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com, Sasha Levin , linux-afs@lists.infradead.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.3 20/99] rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record Date: Sat, 26 Oct 2019 09:14:41 -0400 Message-Id: <20191026131600.2507-20-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191026131600.2507-1-sashal@kernel.org> References: <20191026131600.2507-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Howells [ Upstream commit 9ebeddef58c41bd700419cdcece24cf64ce32276 ] The rxrpc_peer record needs to hold a reference on the rxrpc_local record it points as the peer is used as a base to access information in the rxrpc_local record. This can cause problems in __rxrpc_put_peer(), where we need the network namespace pointer, and in rxrpc_send_keepalive(), where we need to access the UDP socket, leading to symptoms like: BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411 [inline] BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0 net/rxrpc/peer_object.c:435 Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216 Fix this by taking a ref on the local record for the peer record. Fixes: ace45bec6d77 ("rxrpc: Fix firewall route keepalive") Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing") Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com Signed-off-by: David Howells Signed-off-by: Sasha Levin --- net/rxrpc/peer_object.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/rxrpc/peer_object.c b/net/rxrpc/peer_object.c index b700b7ecaa3d8..64830d8c1fdb5 100644 --- a/net/rxrpc/peer_object.c +++ b/net/rxrpc/peer_object.c @@ -216,7 +216,7 @@ struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp) peer = kzalloc(sizeof(struct rxrpc_peer), gfp); if (peer) { atomic_set(&peer->usage, 1); - peer->local = local; + peer->local = rxrpc_get_local(local); INIT_HLIST_HEAD(&peer->error_targets); peer->service_conns = RB_ROOT; seqlock_init(&peer->service_conn_lock); @@ -307,7 +307,6 @@ void rxrpc_new_incoming_peer(struct rxrpc_sock *rx, struct rxrpc_local *local, unsigned long hash_key; hash_key = rxrpc_peer_hash_key(local, &peer->srx); - peer->local = local; rxrpc_init_peer(rx, peer, hash_key); spin_lock(&rxnet->peer_hash_lock); @@ -417,6 +416,7 @@ static void __rxrpc_put_peer(struct rxrpc_peer *peer) list_del_init(&peer->keepalive_link); spin_unlock_bh(&rxnet->peer_hash_lock); + rxrpc_put_local(peer->local); kfree_rcu(peer, rcu); } @@ -453,6 +453,7 @@ void rxrpc_put_peer_locked(struct rxrpc_peer *peer) if (n == 0) { hash_del_rcu(&peer->hash_link); list_del_init(&peer->keepalive_link); + rxrpc_put_local(peer->local); kfree_rcu(peer, rcu); } } -- 2.20.1