From patchwork Fri Mar 14 15:19:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Luczaj X-Patchwork-Id: 14017046 X-Patchwork-Delegate: kuba@kernel.org Received: from mailtransmit05.runbox.com (mailtransmit05.runbox.com [185.226.149.38]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C8591EEA5D; Fri, 14 Mar 2025 15:20:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.226.149.38 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741965642; cv=none; b=Ta8Qwn0E6rtT3CAdW1XQMoGO/VQmZyxRaw1z8VptKtW4S0xez0u00nkadIj/STKjJ0cveY/JzMCLJpIuRqDdfooiV7GZvA+Y6WChmwi0w0mO+pw0K5CZ1P+9Wft2r3DJMATh6IwprNWpAue6bvk6hYjK0HQGla4Du7696xl1ohM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741965642; c=relaxed/simple; bh=3tj+sd1hBSK0PpyiKGpyyTMF/4GJvPBwbGnV9vwWXd0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=JZtRToDUAPzjDlzPuQe2aB6v1xgkRqFY964T54Dg0xR7ZB+zzSIFRVJPWjegvyeQF7BB1EjO1noKISMsOKD3rjVASCb8xfWAzFiwfsVTSIzCKEy2sR6HSeae3LrW8DZXBeVR7T4+uPWZXL5hID8R/NQ/TigCLMsjmxX7BfW1A7w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rbox.co; spf=pass smtp.mailfrom=rbox.co; dkim=pass (2048-bit key) header.d=rbox.co header.i=@rbox.co header.b=VXFF4YHs; arc=none smtp.client-ip=185.226.149.38 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rbox.co Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rbox.co Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rbox.co header.i=@rbox.co header.b="VXFF4YHs" Received: from mailtransmit03.runbox ([10.9.9.163] helo=aibo.runbox.com) by mailtransmit05.runbox.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1tt6pn-006FJJ-Vi; Fri, 14 Mar 2025 16:20:28 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=rbox.co; s=selector1; h=Cc:To:In-Reply-To:References:Message-Id: Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date:From; bh=bxiMFSV63H5IMVOHX04yoU+77ubhpH+TthNc1KSiRUY=; b=VXFF4YHsPf/F2L9RPz6BsmOqCg ZBXqGNMUIZ10SC7ZxmBvwuF6rw8T2lenLcPua1cLGXs4HefKkJYE7hgMJNVQd4ueL8QIx6yOOLHgp 1YlhI4/j7SV9dsEZCNJxCXFWImRT/ZA7AqSHLvEkfj4eqetrf4eDiFK5zX8FUalnmAl9HAx+MPpZV 4wfsMxZJ2xkx9PBsgatTBya0qaF5jusgOxwtlzPEVq6FjzkXmMYSvV4ZEiTD1BeNCbdS7TvL3WCmq vRgrsqog+eKzf+ehnoHLTwCaylyQs0yDv7kuKbVC3mEhKFse9JiPQ2TQIBkqvqZEbwbd5Y0VXIHXz zUvswQSQ==; Received: from [10.9.9.73] (helo=submission02.runbox) by mailtransmit03.runbox with esmtp (Exim 4.86_2) (envelope-from ) id 1tt6pl-0004NT-6i; Fri, 14 Mar 2025 16:20:25 +0100 Received: by submission02.runbox with esmtpsa [Authenticated ID (604044)] (TLS1.2:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.93) id 1tt6pa-00H06E-U6; Fri, 14 Mar 2025 16:20:15 +0100 From: Michal Luczaj Date: Fri, 14 Mar 2025 16:19:34 +0100 Subject: [PATCH net v2 1/3] vsock/bpf: Fix EINTR connect() racing sockmap update Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250314-vsock-trans-signal-race-v2-1-421a41f60f42@rbox.co> References: <20250314-vsock-trans-signal-race-v2-0-421a41f60f42@rbox.co> In-Reply-To: <20250314-vsock-trans-signal-race-v2-0-421a41f60f42@rbox.co> To: Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , "Michael S. Tsirkin" , Bobby Eshleman , Andrii Nakryiko , Eduard Zingerman , Mykola Lysenko , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Michal Luczaj X-Mailer: b4 0.14.2 X-Patchwork-Delegate: kuba@kernel.org Signal delivery during connect() may result in a disconnect of an already TCP_ESTABLISHED socket. Problem is that such established socket might have been placed in a sockmap before the connection was closed. We end up with a SS_UNCONNECTED vsock in a sockmap. And this, combined with the ability to reassign (unconnected) vsock's transport to NULL, breaks the sockmap contract. As manifested by WARN_ON_ONCE. connect / state = SS_CONNECTED / sock_map_update_elem if signal_pending state = SS_UNCONNECTED connect transport = NULL vsock_bpf_recvmsg WARN_ON_ONCE(!vsk->transport) Ensure the socket does not stay in sockmap. WARNING: CPU: 8 PID: 1228 at net/vmw_vsock/vsock_bpf.c:97 vsock_bpf_recvmsg+0xb43/0xe00 CPU: 8 UID: 0 PID: 1228 Comm: a.out Not tainted 6.14.0-rc5+ RIP: 0010:vsock_bpf_recvmsg+0xb43/0xe00 sock_recvmsg+0x1b2/0x220 __sys_recvfrom+0x190/0x270 __x64_sys_recvfrom+0xdc/0x1b0 do_syscall_64+0x93/0x1b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fixes: 634f1a7110b4 ("vsock: support sockmap") Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj --- net/vmw_vsock/af_vsock.c | 10 +++++++++- net/vmw_vsock/vsock_bpf.c | 1 + 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 7e3db87ae4333cf63327ec105ca99253569bb9fe..81b1b8e9c946a646778367ab78ca180cef75ef72 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1579,7 +1579,15 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr, if (signal_pending(current)) { err = sock_intr_errno(timeout); - sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; + if (sk->sk_state == TCP_ESTABLISHED) { + /* Might have raced with a sockmap update. */ + if (sk->sk_prot->unhash) + sk->sk_prot->unhash(sk); + + sk->sk_state = TCP_CLOSING; + } else { + sk->sk_state = TCP_CLOSE; + } sock->state = SS_UNCONNECTED; vsock_transport_cancel_pkt(vsk); vsock_remove_connected(vsk); diff --git a/net/vmw_vsock/vsock_bpf.c b/net/vmw_vsock/vsock_bpf.c index 07b96d56f3a577af71021b1b8132743554996c4f..c68fdaf09046b68254dac3ea70ffbe73dfa45cef 100644 --- a/net/vmw_vsock/vsock_bpf.c +++ b/net/vmw_vsock/vsock_bpf.c @@ -127,6 +127,7 @@ static void vsock_bpf_rebuild_protos(struct proto *prot, const struct proto *bas { *prot = *base; prot->close = sock_map_close; + prot->unhash = sock_map_unhash; prot->recvmsg = vsock_bpf_recvmsg; prot->sock_is_readable = sk_msg_is_readable; }