From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 5.10 6/6] net/x25: Fix to not accept on connected socket Date: Tue, 31 Jan 2023 10:00:58 -0500 Message-ID: <20230131150100.1250267-6-sashal@kernel.org> References: <20230131150100.1250267-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675177270; bh=ix94DxuV/QtR2kk4loRy2CIZBhfC2bzbmIuT+Fcl75Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TciZ+BOlyi3qSbsA87XV81llaI0woQkBkHP8FvnQdRkSAR/NQ4SSdgPjcD6oRCcnn gc8rEAWBtlFn6Haiu+dtmpiayGx9Ry/x1Qdk1NdlEEbJ6SnKOXS0fMtpxE61Tt0hKa z/ssjIhKTnFSMRMKx9cVT07PCaLczV8An6Go80IPb7Eb+0Cym3o2NYa3GPLSt2lZKX EzscysSyk6IzeXw70hI+qio0fiIn58ZuTOE6hd/LtQhgbHh9SVyrYg0guWxAYtzTMX M3cC6XkyoousS+e+GFGOzM08QSnrQeAUJMbYfMcFztDvUTqVejjHFbnU280b+bPVcH 8rHkghQ9+fdNA== In-Reply-To: <20230131150100.1250267-1-sashal@kernel.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hyunwoo Kim , "David S . Miller" , Sasha Levin , ms@dev.tdt.de, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-x25@vger.kernel.org, netdev@vger.kernel.org From: Hyunwoo Kim [ Upstream commit f2b0b5210f67c56a3bcdf92ff665fb285d6e0067 ] When listen() and accept() are called on an x25 socket that connect() succeeds, accept() succeeds immediately. This is because x25_connect() queues the skb to sk->sk_receive_queue, and x25_accept() dequeues it. This creates a child socket with the sk of the parent x25 socket, which can cause confusion. Fix x25_listen() to return -EINVAL if the socket has already been successfully connect()ed to avoid this issue. Signed-off-by: Hyunwoo Kim Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/x25/af_x25.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c index d231d4620c38..161dc194e634 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -492,6 +492,12 @@ static int x25_listen(struct socket *sock, int backlog) int rc = -EOPNOTSUPP; lock_sock(sk); + if (sock->state != SS_UNCONNECTED) { + rc = -EINVAL; + release_sock(sk); + return rc; + } + if (sk->sk_state != TCP_LISTEN) { memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN); sk->sk_max_ack_backlog = backlog; -- 2.39.0