From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id E0D085A028B for ; Mon, 29 Jan 2024 05:36:11 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202312; t=1706502959; bh=hY84O/0U2gr+ehudF0hx/YMyjxhk7dqp5ARPawEbX2s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OkyGB19OoGZ4odyGlFnfYjxNBlQ6gleBXVLgjWmeBRzUIGYV3n1+H7oHzSTkjeLu2 emvZw2CGzN3W30gz9WwZxhx7V4i/QmEyWeTu7kH+k4TL2l887djFTKQ5Yfypbmq/Uu k/m1OznZ7ulg2eNigpk1tG6RnVp+IgxrQ2f4JMt1bnDCMnG90zVk66/HeYcp9kTMKT cRsH2UHrNIqK9yl7cBBtUGtnIWHeIOXj0T9fPKAgq9ry+xcTPvmO9uDwslOuw3bWQD SmBsh3V5sywb09HEkhj6soUaTn5kBnAM9jW89hHuStUqGr7vjrmp2sTAW+GAx69XPD EPFZnlts1G30g== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4TNb8b6DN3z4x5k; Mon, 29 Jan 2024 15:35:59 +1100 (AEDT) From: David Gibson To: Stefano Brivio , passt-dev@passt.top Subject: [PATCH 10/16] tcp_splice: Improve error reporting on connect path Date: Mon, 29 Jan 2024 15:35:51 +1100 Message-ID: <20240129043557.823451-11-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240129043557.823451-1-david@gibson.dropbear.id.au> References: <20240129043557.823451-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: HGIBRSR5VU4HUYUOTSVBNNVHPZQ57IKF X-Message-ID-Hash: HGIBRSR5VU4HUYUOTSVBNNVHPZQ57IKF X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: David Gibson X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: This makes a number of changes to improve error reporting while connecting a new spliced socket: * We use flow_err() and similar functions so all messages include info on which specific flow was affected * We use strerror() to interpret raw error values * We now report errors on connection (at "trace" level, since this would allow spamming the logs) * We also look up and report some details on EPOLLERR events, which can include connection errors, since we use a non-blocking connect(). Again we use "trace" level since this can spam the logs. * Use the 'goto fail' idiom in tcp_splice_conn_from_sock to combine some common handling Signed-off-by: David Gibson --- tcp_splice.c | 36 +++++++++++++++++++++++++++++------- 1 file changed, 29 insertions(+), 7 deletions(-) diff --git a/tcp_splice.c b/tcp_splice.c index 30b4d58a..abd698d4 100644 --- a/tcp_splice.c +++ b/tcp_splice.c @@ -387,7 +387,7 @@ bool tcp_splice_conn_from_sock(const struct ctx *c, in_port_t srcport, dstport = ref.port; union inany_addr src; sa_family_t af; - int s1; + int s1, rc; ASSERT(c->mode == MODE_PASTA); @@ -420,15 +420,25 @@ bool tcp_splice_conn_from_sock(const struct ctx *c, } if (s1 < 0) { - warn("Couldn't open connectable socket for splice (%d)", s1); - conn_flag(c, conn, CLOSING); - return true; + flow_err(conn, + "Couldn't open connectable socket for splice: %s", + strerror(-s1)); + goto fail; } - if (tcp_splice_connect(c, conn, s1, dstport)) - conn_flag(c, conn, CLOSING); + if ((rc = tcp_splice_connect(c, conn, s1, dstport))) { + flow_trace(conn, "Couldn't connect socket for splice: %s", + strerror(-rc)); + goto fail; + } return true; + +fail: + /* This is *supposed* to be a spliced connection, but something went + * wrong */ + conn_flag(c, conn, CLOSING); + return true; } /** @@ -452,8 +462,20 @@ void tcp_splice_sock_handler(struct ctx *c, union epoll_ref ref, if (conn->events == SPLICE_CLOSED) return; - if (events & EPOLLERR) + if (events & EPOLLERR) { + int err, rc; + socklen_t sl = sizeof(err); + + rc = getsockopt(ref.fd, SOL_SOCKET, SO_ERROR, &err, &sl); + if (rc) + flow_err(conn, "Error retrieving SO_ERROR: %s", + strerror(errno)); + else + flow_trace(conn, "Error event on socket: %s", + strerror(err)); + goto close; + } if (conn->events == SPLICE_CONNECT) { if (!(events & EPOLLOUT)) -- 2.43.0