From e66040417b52be98d41ba1230f25dea65147e8ee Mon Sep 17 00:00:00 2001 From: Patrik Flykt Date: Wed, 23 Sep 2015 14:10:26 +0300 Subject: [PATCH] sd-dhcp6-client: Properly handle DHCPv6 client restart after resume Whenever a Router Advertisement is received, dhcp6_configure() will be called. A Router Advertisment can also instruct DHCPv6 to start acquiring IPv6 addresses in manged mode, if it previously was handling only other information. As an Router Advertisment is also received after the DHCPv6 client has resumed from a suspend, fix the function not to assume DHCPv6 is currently running, but instead try to restart it. Handle sd_dhcp6_start() returning -EALREADY indicating that the DHCPv6 client was already running. Collect all client unrefs in one place to unclutter the error handling. Fixes https://github.com/systemd/systemd/issues/963 --- src/network/networkd-dhcp6.c | 86 +++++++++++++++++++++----------------------- 1 file changed, 40 insertions(+), 46 deletions(-) diff --git a/src/network/networkd-dhcp6.c b/src/network/networkd-dhcp6.c index fca73b3..1d85fef 100644 --- a/src/network/networkd-dhcp6.c +++ b/src/network/networkd-dhcp6.c @@ -183,41 +183,42 @@ static int dhcp6_configure(Link *link, int event) { bool information_request; assert_return(link, -EINVAL); + assert_return(IN_SET(event, SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_TIMEOUT, + SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_OTHER, + SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_MANAGED), -EINVAL); if (link->dhcp6_client) { - if (event != SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_MANAGED) - return 0; - r = sd_dhcp6_client_get_information_request(link->dhcp6_client, &information_request); if (r < 0) { log_link_warning(link, "Could not get DHCPv6 Information request setting: %s", - strerror(-r)); - link->dhcp6_client = - sd_dhcp6_client_unref(link->dhcp6_client); - return r; + strerror(-r)); + goto error; } - if (!information_request) - return r; + if (information_request && event != SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_OTHER) { + r = sd_dhcp6_client_stop(link->dhcp6_client); + if (r < 0) { + log_link_warning(link, "Could not stop DHCPv6 while setting Managed mode %s", + strerror(-r)); + goto error; + } + + r = sd_dhcp6_client_set_information_request(link->dhcp6_client, + false); + if (r < 0) { + log_link_warning(link, "Could not unset DHCPv6 Information request: %s", + strerror(-r)); + goto error; + } - r = sd_dhcp6_client_set_information_request(link->dhcp6_client, - false); - if (r < 0) { - log_link_warning(link, "Could not unset DHCPv6 Information request: %s", - strerror(-r)); - link->dhcp6_client = - sd_dhcp6_client_unref(link->dhcp6_client); - return r; } r = sd_dhcp6_client_start(link->dhcp6_client); - if (r < 0) { - log_link_warning(link, "Could not restart DHCPv6 after enabling Information request: %s", - strerror(-r)); - link->dhcp6_client = - sd_dhcp6_client_unref(link->dhcp6_client); - return r; + if (r < 0 && r != -EALREADY) { + log_link_warning(link, "Could not restart DHCPv6: %s", + strerror(-r)); + goto error; } return r; @@ -225,49 +226,42 @@ static int dhcp6_configure(Link *link, int event) { r = sd_dhcp6_client_new(&link->dhcp6_client); if (r < 0) - return r; + goto error; r = sd_dhcp6_client_attach_event(link->dhcp6_client, NULL, 0); - if (r < 0) { - link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); - return r; - } + if (r < 0) + goto error; r = sd_dhcp6_client_set_mac(link->dhcp6_client, (const uint8_t *) &link->mac, sizeof (link->mac), ARPHRD_ETHER); - if (r < 0) { - link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); - return r; - } + if (r < 0) + goto error; r = sd_dhcp6_client_set_index(link->dhcp6_client, link->ifindex); - if (r < 0) { - link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); - return r; - } + if (r < 0) + goto error; r = sd_dhcp6_client_set_callback(link->dhcp6_client, dhcp6_handler, link); - if (r < 0) { - link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); - return r; - } + if (r < 0) + goto error; if (event == SD_ICMP6_ND_EVENT_ROUTER_ADVERTISMENT_OTHER) { r = sd_dhcp6_client_set_information_request(link->dhcp6_client, true); - if (r < 0) { - link->dhcp6_client = - sd_dhcp6_client_unref(link->dhcp6_client); - return r; - } + if (r < 0) + goto error; } r = sd_dhcp6_client_start(link->dhcp6_client); if (r < 0) - link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); + goto error; + + return r; + error: + link->dhcp6_client = sd_dhcp6_client_unref(link->dhcp6_client); return r; } -- 2.7.4