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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham 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 50732C65C20 for ; Mon, 8 Oct 2018 19:02:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 02A5B2089D for ; Mon, 8 Oct 2018 19:02:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="P3PxIXV5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 02A5B2089D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727078AbeJICPh (ORCPT ); Mon, 8 Oct 2018 22:15:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:48942 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730752AbeJICAT (ORCPT ); Mon, 8 Oct 2018 22:00:19 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (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 D25D42064A; Mon, 8 Oct 2018 18:47:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539024433; bh=IsDN8sYWBRcDbsQfeX5KWlSywER9ggdvEMRJF5Q48k4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P3PxIXV5614JMlHLAaMJwm+Fjm/A4hQEHW1gG0cr9Gxil29yQCsxlAIhzCFrWwns7 PTy8oE3YdEfZpUwE5brjj+e4pB9niQSUZ7ED3SxuD3MdZ2s7M2S4FzbPQTJkWH0L+x 3XNrP/ZAiarYT7xy44IOIgHJHm5+QZlyeb36aue4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Borkmann , John Fastabend , Alexei Starovoitov , Sasha Levin Subject: [PATCH 4.18 013/168] bpf, sockmap: fix psock refcount leak in bpf_tcp_recvmsg Date: Mon, 8 Oct 2018 20:29:53 +0200 Message-Id: <20181008175620.542501811@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181008175620.043587728@linuxfoundation.org> References: <20181008175620.043587728@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Borkmann [ Upstream commit 15c480efab01197c965ce0562a43ffedd852b8f9 ] In bpf_tcp_recvmsg() we first took a reference on the psock, however once we find that there are skbs in the normal socket's receive queue we return with processing them through tcp_recvmsg(). Problem is that we leak the taken reference on the psock in that path. Given we don't really do anything with the psock at this point, move the skb_queue_empty() test before we fetch the psock to fix this case. Fixes: 8934ce2fd081 ("bpf: sockmap redirect ingress support") Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/sockmap.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -915,6 +915,8 @@ static int bpf_tcp_recvmsg(struct sock * if (unlikely(flags & MSG_ERRQUEUE)) return inet_recv_error(sk, msg, len, addr_len); + if (!skb_queue_empty(&sk->sk_receive_queue)) + return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); rcu_read_lock(); psock = smap_psock_sk(sk); @@ -925,9 +927,6 @@ static int bpf_tcp_recvmsg(struct sock * goto out; rcu_read_unlock(); - if (!skb_queue_empty(&sk->sk_receive_queue)) - return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); - lock_sock(sk); bytes_ready: while (copied != len) {