From 4591b362e2435ea7ffcb6b02b1975d37b348268f Mon Sep 17 00:00:00 2001 From: Hans Dedecker Date: Mon, 7 May 2018 15:49:13 +0200 Subject: [PATCH] dhcpv4: improve error checking in dhcpv4_setup_interface() Improve error checking fixing resource leakage detected by Coverity in CID 1433402 Signed-off-by: Hans Dedecker --- src/dhcpv4.c | 87 +++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 65 insertions(+), 22 deletions(-) diff --git a/src/dhcpv4.c b/src/dhcpv4.c index 35a3ad0..2b30307 100644 --- a/src/dhcpv4.c +++ b/src/dhcpv4.c @@ -71,6 +71,8 @@ int dhcpv4_init(void) int dhcpv4_setup_interface(struct interface *iface, bool enable) { + int ret = 0; + if (iface->dhcpv4_event.uloop.fd > 0) { uloop_fd_delete(&iface->dhcpv4_event.uloop); close(iface->dhcpv4_event.uloop.fd); @@ -78,55 +80,96 @@ int dhcpv4_setup_interface(struct interface *iface, bool enable) } if (iface->dhcpv4 && enable) { + struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT), + {INADDR_ANY}, {0}}; + int val = 1; + if (!iface->dhcpv4_assignments.next) INIT_LIST_HEAD(&iface->dhcpv4_assignments); if (!iface->dhcpv4_fr_ips.next) INIT_LIST_HEAD(&iface->dhcpv4_fr_ips); - int sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP); - if (sock < 0) { - syslog(LOG_ERR, "Failed to create DHCPv4 server socket: %m"); - return -1; + iface->dhcpv4_event.uloop.fd = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP); + if (iface->dhcpv4_event.uloop.fd < 0) { + syslog(LOG_ERR, "socket(AF_INET): %m"); + ret = -1; + goto out; } /* Basic IPv4 configuration */ - int val = 1; - setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)); - setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &val, sizeof(val)); - setsockopt(sock, IPPROTO_IP, IP_PKTINFO, &val, sizeof(val)); + if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_REUSEADDR, + &val, sizeof(val)) < 0) { + syslog(LOG_ERR, "setsockopt(SO_REUSEADDR): %m"); + ret = -1; + goto out; + } + + if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BROADCAST, + &val, sizeof(val)) < 0) { + syslog(LOG_ERR, "setsockopt(SO_BROADCAST): %m"); + ret = -1; + goto out; + } + + if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_PKTINFO, + &val, sizeof(val))) { + syslog(LOG_ERR, "setsockopt(IP_PKTINFO): %m"); + ret = -1; + goto out; + } val = IPTOS_PREC_INTERNETCONTROL; - setsockopt(sock, IPPROTO_IP, IP_TOS, &val, sizeof(val)); + if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_TOS, + &val, sizeof(val))) { + syslog(LOG_ERR, "setsockopt(IP_TOS): %m"); + ret = -1; + goto out; + } val = IP_PMTUDISC_DONT; - setsockopt(sock, IPPROTO_IP, IP_MTU_DISCOVER, &val, sizeof(val)); + if (setsockopt(iface->dhcpv4_event.uloop.fd, IPPROTO_IP, IP_MTU_DISCOVER, + &val, sizeof(val))) { + syslog(LOG_ERR, "setsockopt(IP_MTU_DISCOVER): %m"); + ret = -1; + goto out; + } - setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, - iface->ifname, strlen(iface->ifname)); + if (setsockopt(iface->dhcpv4_event.uloop.fd, SOL_SOCKET, SO_BINDTODEVICE, + iface->ifname, strlen(iface->ifname))) { + syslog(LOG_ERR, "setsockopt(SO_BINDTODEVICE): %m"); + ret = -1; + goto out; + } - struct sockaddr_in bind_addr = {AF_INET, htons(DHCPV4_SERVER_PORT), - {INADDR_ANY}, {0}}; + if (bind(iface->dhcpv4_event.uloop.fd, (struct sockaddr*)&bind_addr, sizeof(bind_addr))) { + syslog(LOG_ERR, "bind(): %m"); + ret = -1; + goto out; + } - if (bind(sock, (struct sockaddr*)&bind_addr, sizeof(bind_addr))) { - syslog(LOG_ERR, "Failed to open DHCPv4 server socket: %m"); - return -1; + if (setup_dhcpv4_addresses(iface) < 0) { + ret = -1; + goto out; } - iface->dhcpv4_event.uloop.fd = sock; iface->dhcpv4_event.handle_dgram = handle_dhcpv4; odhcpd_register(&iface->dhcpv4_event); - if (setup_dhcpv4_addresses(iface) < 0) - return -1; - update_static_assignments(iface); } else if (iface->dhcpv4_assignments.next) { while (!list_empty(&iface->dhcpv4_assignments)) free_dhcpv4_assignment(list_first_entry(&iface->dhcpv4_assignments, struct dhcpv4_assignment, head)); } - return 0; + +out: + if (ret < 0 && iface->dhcpv4_event.uloop.fd > 0) { + close(iface->dhcpv4_event.uloop.fd); + iface->dhcpv4_event.uloop.fd = -1; + } + + return ret; } -- 2.30.2