libbb: set netlink socket revbuf size before binding

As soon as the socket is bound it will receive messages. Make sure the
recieve buffer size is increased before the first message is received.

Signed-off-by: Jan Klötzke <jan@kloetzke.net>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Jan Klötzke 2019-12-16 22:56:49 +01:00 committed by Denys Vlasenko
parent 9bf4499dd7
commit 12aa68d10f

View File

@ -422,17 +422,14 @@ int FAST_FUNC create_and_bind_to_netlink(int proto, int grp, unsigned rcvbuf)
struct sockaddr_nl sa; struct sockaddr_nl sa;
int fd; 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); fd = xsocket(AF_NETLINK, SOCK_DGRAM, proto);
xbind(fd, (struct sockaddr *) &sa, sizeof(sa));
close_on_exec_on(fd);
/* Set receive buffer size before binding the socket
* We want to have enough space before we start receiving messages.
*/
if (rcvbuf != 0) { 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_RCVBUF, rcvbuf); /* SO_RCVBUFFORCE (root only) can go above net.core.rmem_max */
setsockopt_SOL_SOCKET_int(fd, SO_RCVBUFFORCE, rcvbuf); setsockopt_SOL_SOCKET_int(fd, SO_RCVBUFFORCE, rcvbuf);
# if 0 # if 0
{ {
@ -444,6 +441,13 @@ int FAST_FUNC create_and_bind_to_netlink(int proto, int grp, unsigned rcvbuf)
# endif # endif
} }
memset(&sa, 0, sizeof(sa));
sa.nl_family = AF_NETLINK;
sa.nl_pid = getpid();
sa.nl_groups = grp;
xbind(fd, (struct sockaddr *) &sa, sizeof(sa));
close_on_exec_on(fd);
return fd; return fd;
} }
#endif #endif