| Message ID | a4d75d4de785ee9be7bd24e8a74f5cf3c46dd1a0.1497458933.git-series.knut.omang@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jun 14, 2017 at 06:53:52PM +0200, Knut Omang wrote: > If an offset of ports is specified to the inet_listen_saddr function(), > and two or more processes tries to bind from these ports at the same time, > occasionally more than one process may be able to bind to the same > port. The condition is detected by listen() but too late to avoid a failure. > > This function is called by socket_listen() and used > by all socket listening code in QEMU, so all cases where any form of dynamic > port selection is used should be subject to this issue. > > Add code to close and re-establish the socket when this > condition is observed, hiding the race condition from the user. > > This has been developed and tested by means of the > test-listen unit test in the previous commit. > Enable the test for make check now that it passes. > > Signed-off-by: Knut Omang <knut.omang@oracle.com> > Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com> > Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com> > Reviewed-by: Girish Moodalbail <girish.moodalbail@oracle.com> > --- > tests/Makefile.include | 2 +- > util/qemu-sockets.c | 159 ++++++++++++++++++++++++++++-------------- > 2 files changed, 108 insertions(+), 53 deletions(-) > > diff --git a/tests/Makefile.include b/tests/Makefile.include > index 22bb97e..c38f94e 100644 > --- a/tests/Makefile.include > +++ b/tests/Makefile.include > @@ -127,7 +127,7 @@ check-unit-y += tests/test-bufferiszero$(EXESUF) > gcov-files-check-bufferiszero-y = util/bufferiszero.c > check-unit-y += tests/test-uuid$(EXESUF) > check-unit-y += tests/ptimer-test$(EXESUF) > -#check-unit-y += tests/test-listen$(EXESUF) > +check-unit-y += tests/test-listen$(EXESUF) > gcov-files-ptimer-test-y = hw/core/ptimer.c > check-unit-y += tests/test-qapi-util$(EXESUF) > gcov-files-test-qapi-util-y = qapi/qapi-util.c > diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c > index 852773d..7b118b4 100644 > --- a/util/qemu-sockets.c > +++ b/util/qemu-sockets.c > @@ -149,6 +149,94 @@ int inet_ai_family_from_address(InetSocketAddress *addr, > return PF_UNSPEC; > } > > +static int create_fast_reuse_socket(struct addrinfo *e, Error **errp) > +{ > + int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); > + if (slisten < 0) { > + if (!e->ai_next) { > + error_setg_errno(errp, errno, "Failed to create socket"); > + } > + return -1; > + } > + > + socket_set_fast_reuse(slisten); > + return slisten; > +} > + > +static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e) > +{ > +#ifndef IPV6_V6ONLY > + return bind(socket, e->ai_addr, e->ai_addrlen); > +#else > + /* > + * Deals with first & last cases in matrix in comment > + * for inet_ai_family_from_address(). > + */ > + int v6only = > + ((!saddr->has_ipv4 && !saddr->has_ipv6) || > + (saddr->has_ipv4 && saddr->ipv4 && > + saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; > + int stat; > + > + rebind: > + if (e->ai_family == PF_INET6) { > + qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, > + sizeof(v6only)); > + } > + > + stat = bind(socket, e->ai_addr, e->ai_addrlen); > + if (!stat) { > + return 0; > + } > + > + /* If we got EADDRINUSE from an IPv6 bind & v6only is unset, > + * it could be that the IPv4 port is already claimed, so retry > + * with v6only set > + */ > + if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { > + v6only = 1; > + goto rebind; > + } > + return stat; > +#endif > +} > + > +static int try_bind_listen(int *socket, InetSocketAddress *saddr, > + struct addrinfo *e, int port, Error **errp) > +{ > + int s = *socket; > + int ret; > + > + inet_setport(e, port); > + ret = try_bind(s, saddr, e); > + if (ret) { > + if (errno != EADDRINUSE) { > + error_setg_errno(errp, errno, "Failed to bind socket"); > + } > + return errno; > + } > + if (listen(s, 1) == 0) { > + return 0; > + } > + if (errno == EADDRINUSE) { > + /* We got to bind the socket to a port but someone else managed > + * to bind to the same port and beat us to listen on it! > + * Recreate the socket and return EADDRINUSE to preserve the > + * expected state by the caller: > + */ > + closesocket(s); > + s = create_fast_reuse_socket(e, errp); > + if (s < 0) { > + return errno; > + } > + *socket = s; > + errno = EADDRINUSE; > + return errno; > + } > + error_setg_errno(errp, errno, "Failed to listen on socket"); > + return errno; > +} > + > static int inet_listen_saddr(InetSocketAddress *saddr, > int port_offset, > bool update_addr, > @@ -158,7 +246,9 @@ static int inet_listen_saddr(InetSocketAddress *saddr, > char port[33]; > char uaddr[INET6_ADDRSTRLEN+1]; > char uport[33]; > - int slisten, rc, port_min, port_max, p; > + int rc, port_min, port_max, p; > + int slisten = 0; > + int saved_errno = 0; > Error *err = NULL; > > memset(&ai,0, sizeof(ai)); > @@ -210,75 +300,40 @@ static int inet_listen_saddr(InetSocketAddress *saddr, > return -1; > } > > - /* create socket + bind */ > + /* create socket + bind/listen */ > for (e = res; e != NULL; e = e->ai_next) { > getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen, > uaddr,INET6_ADDRSTRLEN,uport,32, > NI_NUMERICHOST | NI_NUMERICSERV); > - slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); > + > + slisten = create_fast_reuse_socket(e, &err); > if (slisten < 0) { > - if (!e->ai_next) { > - error_setg_errno(errp, errno, "Failed to create socket"); > - } > continue; > } > > - socket_set_fast_reuse(slisten); > - > port_min = inet_getport(e); > port_max = saddr->has_to ? saddr->to + port_offset : port_min; > for (p = port_min; p <= port_max; p++) { > -#ifdef IPV6_V6ONLY > - /* > - * Deals with first & last cases in matrix in comment > - * for inet_ai_family_from_address(). > - */ > - int v6only = > - ((!saddr->has_ipv4 && !saddr->has_ipv6) || > - (saddr->has_ipv4 && saddr->ipv4 && > - saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; > -#endif > - inet_setport(e, p); > -#ifdef IPV6_V6ONLY > - rebind: > - if (e->ai_family == PF_INET6) { > - qemu_setsockopt(slisten, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, > - sizeof(v6only)); > - } > -#endif > - if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) { > - goto listen; > - } > - > -#ifdef IPV6_V6ONLY > - /* If we got EADDRINUSE from an IPv6 bind & V6ONLY is unset, > - * it could be that the IPv4 port is already claimed, so retry > - * with V6ONLY set > - */ > - if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { > - v6only = 1; > - goto rebind; > - } > -#endif > - > - if (p == port_max) { > - if (!e->ai_next) { > - error_setg_errno(errp, errno, "Failed to bind socket"); > - } > + int eno = try_bind_listen(&slisten, saddr, e, p, &err); > + if (!eno) { > + goto listen_ok; > + } else if (eno != EADDRINUSE) { > + goto listen_failed; > } > } > + } > + error_setg_errno(errp, errno, "Failed to find available port"); > + > +listen_failed: > + saved_errno = errno; > + if (slisten >= 0) { > closesocket(slisten); > } > freeaddrinfo(res); > + errno = saved_errno; > return -1; > > -listen: > - if (listen(slisten,1) != 0) { > - error_setg_errno(errp, errno, "Failed to listen on socket"); > - closesocket(slisten); > - freeaddrinfo(res); > - return -1; > - } > +listen_ok: > if (update_addr) { > g_free(saddr->host); > saddr->host = g_strdup(uaddr); I find this patch rather hard to review for correctness, because it has mixed up a huge amount of code movement / refactoring, with the bug fix. Can you split this up into 2 (or possibly more) patches, so we have 1 (or more) no-functional-change refactoring steps, and then the bug fix on its own. Regards, Daniel
On Fri, 2017-06-16 at 15:45 +0100, Daniel P. Berrange wrote: > On Wed, Jun 14, 2017 at 06:53:52PM +0200, Knut Omang wrote: > > If an offset of ports is specified to the inet_listen_saddr function(), > > and two or more processes tries to bind from these ports at the same time, > > occasionally more than one process may be able to bind to the same > > port. The condition is detected by listen() but too late to avoid a failure. > > > > This function is called by socket_listen() and used > > by all socket listening code in QEMU, so all cases where any form of dynamic > > port selection is used should be subject to this issue. > > > > Add code to close and re-establish the socket when this > > condition is observed, hiding the race condition from the user. > > > > This has been developed and tested by means of the > > test-listen unit test in the previous commit. > > Enable the test for make check now that it passes. > > > > Signed-off-by: Knut Omang <knut.omang@oracle.com> > > Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com> > > Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com> > > Reviewed-by: Girish Moodalbail <girish.moodalbail@oracle.com> > > --- > > tests/Makefile.include | 2 +- > > util/qemu-sockets.c | 159 ++++++++++++++++++++++++++++-------------- > > 2 files changed, 108 insertions(+), 53 deletions(-) > > > > diff --git a/tests/Makefile.include b/tests/Makefile.include > > index 22bb97e..c38f94e 100644 > > --- a/tests/Makefile.include > > +++ b/tests/Makefile.include > > @@ -127,7 +127,7 @@ check-unit-y += tests/test-bufferiszero$(EXESUF) > > gcov-files-check-bufferiszero-y = util/bufferiszero.c > > check-unit-y += tests/test-uuid$(EXESUF) > > check-unit-y += tests/ptimer-test$(EXESUF) > > -#check-unit-y += tests/test-listen$(EXESUF) > > +check-unit-y += tests/test-listen$(EXESUF) > > gcov-files-ptimer-test-y = hw/core/ptimer.c > > check-unit-y += tests/test-qapi-util$(EXESUF) > > gcov-files-test-qapi-util-y = qapi/qapi-util.c > > diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c > > index 852773d..7b118b4 100644 > > --- a/util/qemu-sockets.c > > +++ b/util/qemu-sockets.c > > @@ -149,6 +149,94 @@ int inet_ai_family_from_address(InetSocketAddress *addr, > > return PF_UNSPEC; > > } > > > > +static int create_fast_reuse_socket(struct addrinfo *e, Error **errp) > > +{ > > + int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); > > + if (slisten < 0) { > > + if (!e->ai_next) { > > + error_setg_errno(errp, errno, "Failed to create socket"); > > + } > > + return -1; > > + } > > + > > + socket_set_fast_reuse(slisten); > > + return slisten; > > +} > > + > > +static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e) > > +{ > > +#ifndef IPV6_V6ONLY > > + return bind(socket, e->ai_addr, e->ai_addrlen); > > +#else > > + /* > > + * Deals with first & last cases in matrix in comment > > + * for inet_ai_family_from_address(). > > + */ > > + int v6only = > > + ((!saddr->has_ipv4 && !saddr->has_ipv6) || > > + (saddr->has_ipv4 && saddr->ipv4 && > > + saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; > > + int stat; > > + > > + rebind: > > + if (e->ai_family == PF_INET6) { > > + qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, > > + sizeof(v6only)); > > + } > > + > > + stat = bind(socket, e->ai_addr, e->ai_addrlen); > > + if (!stat) { > > + return 0; > > + } > > + > > + /* If we got EADDRINUSE from an IPv6 bind & v6only is unset, > > + * it could be that the IPv4 port is already claimed, so retry > > + * with v6only set > > + */ > > + if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { > > + v6only = 1; > > + goto rebind; > > + } > > + return stat; > > +#endif > > +} > > + > > +static int try_bind_listen(int *socket, InetSocketAddress *saddr, > > + struct addrinfo *e, int port, Error **errp) > > +{ > > + int s = *socket; > > + int ret; > > + > > + inet_setport(e, port); > > + ret = try_bind(s, saddr, e); > > + if (ret) { > > + if (errno != EADDRINUSE) { > > + error_setg_errno(errp, errno, "Failed to bind socket"); > > + } > > + return errno; > > + } > > + if (listen(s, 1) == 0) { > > + return 0; > > + } > > + if (errno == EADDRINUSE) { > > + /* We got to bind the socket to a port but someone else managed > > + * to bind to the same port and beat us to listen on it! > > + * Recreate the socket and return EADDRINUSE to preserve the > > + * expected state by the caller: > > + */ > > + closesocket(s); > > + s = create_fast_reuse_socket(e, errp); > > + if (s < 0) { > > + return errno; > > + } > > + *socket = s; > > + errno = EADDRINUSE; > > + return errno; > > + } > > + error_setg_errno(errp, errno, "Failed to listen on socket"); > > + return errno; > > +} > > + > > static int inet_listen_saddr(InetSocketAddress *saddr, > > int port_offset, > > bool update_addr, > > @@ -158,7 +246,9 @@ static int inet_listen_saddr(InetSocketAddress *saddr, > > char port[33]; > > char uaddr[INET6_ADDRSTRLEN+1]; > > char uport[33]; > > - int slisten, rc, port_min, port_max, p; > > + int rc, port_min, port_max, p; > > + int slisten = 0; > > + int saved_errno = 0; > > Error *err = NULL; > > > > memset(&ai,0, sizeof(ai)); > > @@ -210,75 +300,40 @@ static int inet_listen_saddr(InetSocketAddress *saddr, > > return -1; > > } > > > > - /* create socket + bind */ > > + /* create socket + bind/listen */ > > for (e = res; e != NULL; e = e->ai_next) { > > getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen, > > uaddr,INET6_ADDRSTRLEN,uport,32, > > NI_NUMERICHOST | NI_NUMERICSERV); > > - slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); > > + > > + slisten = create_fast_reuse_socket(e, &err); > > if (slisten < 0) { > > - if (!e->ai_next) { > > - error_setg_errno(errp, errno, "Failed to create socket"); > > - } > > continue; > > } > > > > - socket_set_fast_reuse(slisten); > > - > > port_min = inet_getport(e); > > port_max = saddr->has_to ? saddr->to + port_offset : port_min; > > for (p = port_min; p <= port_max; p++) { > > -#ifdef IPV6_V6ONLY > > - /* > > - * Deals with first & last cases in matrix in comment > > - * for inet_ai_family_from_address(). > > - */ > > - int v6only = > > - ((!saddr->has_ipv4 && !saddr->has_ipv6) || > > - (saddr->has_ipv4 && saddr->ipv4 && > > - saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; > > -#endif > > - inet_setport(e, p); > > -#ifdef IPV6_V6ONLY > > - rebind: > > - if (e->ai_family == PF_INET6) { > > - qemu_setsockopt(slisten, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, > > - sizeof(v6only)); > > - } > > -#endif > > - if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) { > > - goto listen; > > - } > > - > > -#ifdef IPV6_V6ONLY > > - /* If we got EADDRINUSE from an IPv6 bind & V6ONLY is unset, > > - * it could be that the IPv4 port is already claimed, so retry > > - * with V6ONLY set > > - */ > > - if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { > > - v6only = 1; > > - goto rebind; > > - } > > -#endif > > - > > - if (p == port_max) { > > - if (!e->ai_next) { > > - error_setg_errno(errp, errno, "Failed to bind socket"); > > - } > > + int eno = try_bind_listen(&slisten, saddr, e, p, &err); > > + if (!eno) { > > + goto listen_ok; > > + } else if (eno != EADDRINUSE) { > > + goto listen_failed; > > } > > } > > + } > > + error_setg_errno(errp, errno, "Failed to find available port"); > > + > > +listen_failed: > > + saved_errno = errno; > > + if (slisten >= 0) { > > closesocket(slisten); > > } > > freeaddrinfo(res); > > + errno = saved_errno; > > return -1; > > > > -listen: > > - if (listen(slisten,1) != 0) { > > - error_setg_errno(errp, errno, "Failed to listen on socket"); > > - closesocket(slisten); > > - freeaddrinfo(res); > > - return -1; > > - } > > +listen_ok: > > if (update_addr) { > > g_free(saddr->host); > > saddr->host = g_strdup(uaddr); > > I find this patch rather hard to review for correctness, because it has > mixed up a huge amount of code movement / refactoring, with the bug > fix. Can you split this up into 2 (or possibly more) patches, so we have > 1 (or more) no-functional-change refactoring steps, and then the bug fix > on its own. Ok, I'll see what I can do - I realize the patch became a great deal more complicated by the refactoring from v2 to v3 to accomodate the IPv6 changes. Thanks, Knut > > Regards, > Daniel
diff --git a/tests/Makefile.include b/tests/Makefile.include index 22bb97e..c38f94e 100644 --- a/tests/Makefile.include +++ b/tests/Makefile.include @@ -127,7 +127,7 @@ check-unit-y += tests/test-bufferiszero$(EXESUF) gcov-files-check-bufferiszero-y = util/bufferiszero.c check-unit-y += tests/test-uuid$(EXESUF) check-unit-y += tests/ptimer-test$(EXESUF) -#check-unit-y += tests/test-listen$(EXESUF) +check-unit-y += tests/test-listen$(EXESUF) gcov-files-ptimer-test-y = hw/core/ptimer.c check-unit-y += tests/test-qapi-util$(EXESUF) gcov-files-test-qapi-util-y = qapi/qapi-util.c diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c index 852773d..7b118b4 100644 --- a/util/qemu-sockets.c +++ b/util/qemu-sockets.c @@ -149,6 +149,94 @@ int inet_ai_family_from_address(InetSocketAddress *addr, return PF_UNSPEC; } +static int create_fast_reuse_socket(struct addrinfo *e, Error **errp) +{ + int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); + if (slisten < 0) { + if (!e->ai_next) { + error_setg_errno(errp, errno, "Failed to create socket"); + } + return -1; + } + + socket_set_fast_reuse(slisten); + return slisten; +} + +static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e) +{ +#ifndef IPV6_V6ONLY + return bind(socket, e->ai_addr, e->ai_addrlen); +#else + /* + * Deals with first & last cases in matrix in comment + * for inet_ai_family_from_address(). + */ + int v6only = + ((!saddr->has_ipv4 && !saddr->has_ipv6) || + (saddr->has_ipv4 && saddr->ipv4 && + saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; + int stat; + + rebind: + if (e->ai_family == PF_INET6) { + qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, + sizeof(v6only)); + } + + stat = bind(socket, e->ai_addr, e->ai_addrlen); + if (!stat) { + return 0; + } + + /* If we got EADDRINUSE from an IPv6 bind & v6only is unset, + * it could be that the IPv4 port is already claimed, so retry + * with v6only set + */ + if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { + v6only = 1; + goto rebind; + } + return stat; +#endif +} + +static int try_bind_listen(int *socket, InetSocketAddress *saddr, + struct addrinfo *e, int port, Error **errp) +{ + int s = *socket; + int ret; + + inet_setport(e, port); + ret = try_bind(s, saddr, e); + if (ret) { + if (errno != EADDRINUSE) { + error_setg_errno(errp, errno, "Failed to bind socket"); + } + return errno; + } + if (listen(s, 1) == 0) { + return 0; + } + if (errno == EADDRINUSE) { + /* We got to bind the socket to a port but someone else managed + * to bind to the same port and beat us to listen on it! + * Recreate the socket and return EADDRINUSE to preserve the + * expected state by the caller: + */ + closesocket(s); + s = create_fast_reuse_socket(e, errp); + if (s < 0) { + return errno; + } + *socket = s; + errno = EADDRINUSE; + return errno; + } + error_setg_errno(errp, errno, "Failed to listen on socket"); + return errno; +} + static int inet_listen_saddr(InetSocketAddress *saddr, int port_offset, bool update_addr, @@ -158,7 +246,9 @@ static int inet_listen_saddr(InetSocketAddress *saddr, char port[33]; char uaddr[INET6_ADDRSTRLEN+1]; char uport[33]; - int slisten, rc, port_min, port_max, p; + int rc, port_min, port_max, p; + int slisten = 0; + int saved_errno = 0; Error *err = NULL; memset(&ai,0, sizeof(ai)); @@ -210,75 +300,40 @@ static int inet_listen_saddr(InetSocketAddress *saddr, return -1; } - /* create socket + bind */ + /* create socket + bind/listen */ for (e = res; e != NULL; e = e->ai_next) { getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen, uaddr,INET6_ADDRSTRLEN,uport,32, NI_NUMERICHOST | NI_NUMERICSERV); - slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol); + + slisten = create_fast_reuse_socket(e, &err); if (slisten < 0) { - if (!e->ai_next) { - error_setg_errno(errp, errno, "Failed to create socket"); - } continue; } - socket_set_fast_reuse(slisten); - port_min = inet_getport(e); port_max = saddr->has_to ? saddr->to + port_offset : port_min; for (p = port_min; p <= port_max; p++) { -#ifdef IPV6_V6ONLY - /* - * Deals with first & last cases in matrix in comment - * for inet_ai_family_from_address(). - */ - int v6only = - ((!saddr->has_ipv4 && !saddr->has_ipv6) || - (saddr->has_ipv4 && saddr->ipv4 && - saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1; -#endif - inet_setport(e, p); -#ifdef IPV6_V6ONLY - rebind: - if (e->ai_family == PF_INET6) { - qemu_setsockopt(slisten, IPPROTO_IPV6, IPV6_V6ONLY, &v6only, - sizeof(v6only)); - } -#endif - if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) { - goto listen; - } - -#ifdef IPV6_V6ONLY - /* If we got EADDRINUSE from an IPv6 bind & V6ONLY is unset, - * it could be that the IPv4 port is already claimed, so retry - * with V6ONLY set - */ - if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) { - v6only = 1; - goto rebind; - } -#endif - - if (p == port_max) { - if (!e->ai_next) { - error_setg_errno(errp, errno, "Failed to bind socket"); - } + int eno = try_bind_listen(&slisten, saddr, e, p, &err); + if (!eno) { + goto listen_ok; + } else if (eno != EADDRINUSE) { + goto listen_failed; } } + } + error_setg_errno(errp, errno, "Failed to find available port"); + +listen_failed: + saved_errno = errno; + if (slisten >= 0) { closesocket(slisten); } freeaddrinfo(res); + errno = saved_errno; return -1; -listen: - if (listen(slisten,1) != 0) { - error_setg_errno(errp, errno, "Failed to listen on socket"); - closesocket(slisten); - freeaddrinfo(res); - return -1; - } +listen_ok: if (update_addr) { g_free(saddr->host); saddr->host = g_strdup(uaddr);