From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44815) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1atkhS-0003SC-HN for qemu-devel@nongnu.org; Fri, 22 Apr 2016 19:41:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1atkhR-0005HE-9V for qemu-devel@nongnu.org; Fri, 22 Apr 2016 19:41:26 -0400 From: Eric Blake Date: Fri, 22 Apr 2016 17:40:10 -0600 Message-Id: <1461368452-10389-3-git-send-email-eblake@redhat.com> In-Reply-To: <1461368452-10389-1-git-send-email-eblake@redhat.com> References: <1461368452-10389-1-git-send-email-eblake@redhat.com> Subject: [Qemu-devel] [PATCH v3 02/44] nbd: Quit server after any write error List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, alex@alex.org.uk, Paolo Bonzini We should never ignore failure from nbd_negotiate_send_rep(); if we are unable to write to the client, then it is not worth trying to continue the negotiation. Fortunately, the problem is not too severe - chances are that the errors being ignored here (mainly inability to write the reply to the client) are indications of a closed connection or something similar, which will also affect the next attempt to interact with the client and eventually reach a point where the errors are detected to end the loop. Signed-off-by: Eric Blake --- nbd/server.c | 32 +++++++++++++++++++++++--------- 1 file changed, 23 insertions(+), 9 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index fc36f4d..0a003e4 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -334,7 +334,10 @@ static QIOChannel *nbd_negotiate_handle_starttls(NBDClient *client, return NULL; } - nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, NBD_OPT_STARTTLS); + if (nbd_negotiate_send_rep(client->ioc, NBD_REP_ACK, + NBD_OPT_STARTTLS) < 0) { + return NULL; + } tioc = qio_channel_tls_new_server(ioc, client->tlscreds, @@ -460,8 +463,11 @@ static int nbd_negotiate_options(NBDClient *client) if (nbd_negotiate_drop_sync(client->ioc, length) != length) { return -EIO; } - nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_TLS_REQD, - clientflags); + ret = nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_TLS_REQD, + clientflags); + if (ret < 0) { + return ret; + } break; } } else if (fixedNewstyle) { @@ -485,12 +491,17 @@ static int nbd_negotiate_options(NBDClient *client) } if (client->tlscreds) { TRACE("TLS already enabled"); - nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_INVALID, - clientflags); + ret = nbd_negotiate_send_rep(client->ioc, + NBD_REP_ERR_INVALID, + clientflags); } else { TRACE("TLS not configured"); - nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_POLICY, - clientflags); + ret = nbd_negotiate_send_rep(client->ioc, + NBD_REP_ERR_POLICY, + clientflags); + } + if (ret < 0) { + return ret; } break; default: @@ -498,8 +509,11 @@ static int nbd_negotiate_options(NBDClient *client) if (nbd_negotiate_drop_sync(client->ioc, length) != length) { return -EIO; } - nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, - clientflags); + ret = nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, + clientflags); + if (ret < 0) { + return ret; + } break; } } else { -- 2.5.5