diff options
| -rw-r--r-- | include/libbb.h | 1 | ||||
| -rw-r--r-- | libbb/xconnect.c | 35 | ||||
| -rw-r--r-- | networking/ifplugd.c | 10 | ||||
| -rw-r--r-- | util-linux/mdev.c | 28 | ||||
| -rw-r--r-- | util-linux/uevent.c | 37 |
5 files changed, 55 insertions, 56 deletions
diff --git a/include/libbb.h b/include/libbb.h index 3a870bf..100d6b6 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -688,6 +688,7 @@ int xsocket_stream(len_and_sockaddr **lsap) FAST_FUNC; /* NB: these set SO_REUSEADDR before bind */ int create_and_bind_stream_or_die(const char *bindaddr, int port) FAST_FUNC; int create_and_bind_dgram_or_die(const char *bindaddr, int port) FAST_FUNC; +int create_and_bind_to_netlink(int proto, int grp, unsigned rcvbuf) FAST_FUNC; /* Create client TCP socket connected to peer:port. Peer cannot be NULL. * Peer can be numeric IP ("N.N.N.N"), numeric IPv6 address or hostname, * and can have ":PORT" suffix (for IPv6 use "[X:X:...:X]:PORT"). diff --git a/libbb/xconnect.c b/libbb/xconnect.c index 39e56b2..ea5fe17 100644 --- a/libbb/xconnect.c +++ b/libbb/xconnect.c @@ -11,6 +11,9 @@ #include <netinet/in.h> #include <net/if.h> #include <sys/un.h> +#if ENABLE_IFPLUGD || ENABLE_FEATURE_MDEV_DAEMON || ENABLE_UEVENT +# include <linux/netlink.h> +#endif #include "libbb.h" int FAST_FUNC setsockopt_int(int fd, int level, int optname, int optval) @@ -412,6 +415,38 @@ int FAST_FUNC create_and_bind_dgram_or_die(const char *bindaddr, int port) } +#if ENABLE_IFPLUGD || ENABLE_FEATURE_MDEV_DAEMON || ENABLE_UEVENT +int FAST_FUNC create_and_bind_to_netlink(int proto, int grp, unsigned rcvbuf) +{ + struct sockaddr_nl sa; + int fd; + + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + sa.nl_pid = getpid(); + sa.nl_groups = grp; + fd = xsocket(AF_NETLINK, SOCK_DGRAM, proto); + xbind(fd, (struct sockaddr *) &sa, sizeof(sa)); + close_on_exec_on(fd); + + if (rcvbuf != 0) { + // SO_RCVBUFFORCE (root only) can go above net.core.rmem_max sysctl + setsockopt_SOL_SOCKET_int(fd, SO_RCVBUF, rcvbuf); + setsockopt_SOL_SOCKET_int(fd, SO_RCVBUFFORCE, rcvbuf); +# if 0 + { + int z; + socklen_t zl = sizeof(z); + getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &z, &zl); + bb_error_msg("SO_RCVBUF:%d", z); + } +# endif + } + + return fd; +} +#endif + int FAST_FUNC create_and_connect_stream_or_die(const char *peer, int port) { int fd; diff --git a/networking/ifplugd.c b/networking/ifplugd.c index 1426709..b7b26c1 100644 --- a/networking/ifplugd.c +++ b/networking/ifplugd.c @@ -604,15 +604,7 @@ int ifplugd_main(int argc UNUSED_PARAM, char **argv) xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), ioctl_fd); if (opts & FLAG_MONITOR) { - struct sockaddr_nl addr; - int fd = xsocket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); - - memset(&addr, 0, sizeof(addr)); - addr.nl_family = AF_NETLINK; - addr.nl_groups = RTMGRP_LINK; - addr.nl_pid = getpid(); - - xbind(fd, (struct sockaddr*)&addr, sizeof(addr)); + int fd = create_and_bind_to_netlink(NETLINK_ROUTE, RTMGRP_LINK, 0); xmove_fd(fd, netlink_fd); } diff --git a/util-linux/mdev.c b/util-linux/mdev.c index 88c82b6..9cb3586 100644 --- a/util-linux/mdev.c +++ b/util-linux/mdev.c @@ -1225,28 +1225,16 @@ int mdev_main(int argc UNUSED_PARAM, char **argv) /* * Daemon mode listening on uevent netlink socket. */ - struct sockaddr_nl sa; int fd; -//TODO: reuse same code in uevent - // Subscribe for UEVENT kernel messages - sa.nl_family = AF_NETLINK; - sa.nl_pad = 0; - sa.nl_pid = getpid(); - sa.nl_groups = 1 << 0; - fd = xsocket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); - xbind(fd, (struct sockaddr *) &sa, sizeof(sa)); - close_on_exec_on(fd); - - // Without a sufficiently big RCVBUF, a ton of simultaneous events - // can trigger ENOBUFS on read, which is unrecoverable. - // Reproducer: - // mdev -d - // find /sys -name uevent -exec sh -c 'echo add >"{}"' ';' - // - // SO_RCVBUFFORCE (root only) can go above net.core.rmem_max sysctl - setsockopt_SOL_SOCKET_int(fd, SO_RCVBUF, RCVBUF); - setsockopt_SOL_SOCKET_int(fd, SO_RCVBUFFORCE, RCVBUF); + /* Subscribe for UEVENT kernel messages */ + /* Without a sufficiently big RCVBUF, a ton of simultaneous events + * can trigger ENOBUFS on read, which is unrecoverable. + * Reproducer: + * mdev -d + * find /sys -name uevent -exec sh -c 'echo add >"{}"' ';' + */ + fd = create_and_bind_to_netlink(NETLINK_KOBJECT_UEVENT, 1 << 0, RCVBUF); /* * Make inital scan after the uevent socket is alive and diff --git a/util-linux/uevent.c b/util-linux/uevent.c index 761743f..2f8990e 100644 --- a/util-linux/uevent.c +++ b/util-linux/uevent.c @@ -46,37 +46,19 @@ enum { RCVBUF = 2 * 1024 * 1024 }; int uevent_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int uevent_main(int argc UNUSED_PARAM, char **argv) { - struct sockaddr_nl sa; int fd; INIT_G(); argv++; - // Subscribe for UEVENT kernel messages - sa.nl_family = AF_NETLINK; - sa.nl_pad = 0; - sa.nl_pid = getpid(); - sa.nl_groups = 1 << 0; - fd = xsocket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); - xbind(fd, (struct sockaddr *) &sa, sizeof(sa)); - close_on_exec_on(fd); - + // Subscribe for UEVENT kernel messages. // Without a sufficiently big RCVBUF, a ton of simultaneous events // can trigger ENOBUFS on read, which is unrecoverable. // Reproducer: // uevent mdev & // find /sys -name uevent -exec sh -c 'echo add >"{}"' ';' - // - // SO_RCVBUFFORCE (root only) can go above net.core.rmem_max sysctl - setsockopt_SOL_SOCKET_int(fd, SO_RCVBUF, RCVBUF); - setsockopt_SOL_SOCKET_int(fd, SO_RCVBUFFORCE, RCVBUF); - if (0) { - int z; - socklen_t zl = sizeof(z); - getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &z, &zl); - bb_error_msg("SO_RCVBUF:%d", z); - } + fd = create_and_bind_to_netlink(NETLINK_KOBJECT_UEVENT, /*groups:*/ 1 << 0, RCVBUF); for (;;) { char *netbuf; @@ -118,14 +100,15 @@ int uevent_main(int argc UNUSED_PARAM, char **argv) } env[idx] = NULL; - idx = 0; - while (env[idx]) - putenv(env[idx++]); - if (argv[0]) + if (argv[0]) { + idx = 0; + while (env[idx]) + putenv(env[idx++]); spawn_and_wait(argv); - idx = 0; - while (env[idx]) - bb_unsetenv(env[idx++]); + idx = 0; + while (env[idx]) + bb_unsetenv(env[idx++]); + } munmap(netbuf, BUFFER_SIZE); } |