From f1ef81b2476ea533ac3d2129aa0e89653c427323 Mon Sep 17 00:00:00 2001 From: Ulrich Weber Date: Tue, 22 Jan 2013 10:39:18 +0000 Subject: [PATCH] zebra: use SO_RCVBUFFORCE for netlink socket so net.core.rmem_max must not be adjusted. Requires linux kernel >= 2.6.14, falls back to SO_RCVBUF on error Signed-off-by: Ulrich Weber Signed-off-by: David Lamparter --- doc/zebra.8 | 2 +- zebra/rt_netlink.c | 14 +++++++++++++- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/doc/zebra.8 b/doc/zebra.8 index 23703e727..a40909a69 100644 --- a/doc/zebra.8 +++ b/doc/zebra.8 @@ -80,7 +80,7 @@ handle flood of netlink messages from kernel. If you ever see "recvmsg overrun" messages in zebra log, you are in trouble. Solution is to increase receive buffer of netlink socket. Note that kernel -doesn't allow to increase it over maximum value defined in +< 2.6.14 doesn't allow to increase it over maximum value defined in \fI/proc/sys/net/core/rmem_max\fR. If you want to do it, you have to increase maximum before starting zebra. diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c index fa446a56f..bab170371 100644 --- a/zebra/rt_netlink.c +++ b/zebra/rt_netlink.c @@ -101,6 +101,10 @@ set_ifindex(struct interface *ifp, unsigned int ifi_index) ifp->ifindex = ifi_index; } +#ifndef SO_RCVBUFFORCE +#define SO_RCVBUFFORCE (33) +#endif + static int netlink_recvbuf (struct nlsock *nl, uint32_t newsize) { @@ -117,8 +121,16 @@ netlink_recvbuf (struct nlsock *nl, uint32_t newsize) return -1; } - ret = setsockopt(nl->sock, SOL_SOCKET, SO_RCVBUF, &nl_rcvbufsize, + /* Try force option (linux >= 2.6.14) and fall back to normal set */ + if ( zserv_privs.change (ZPRIVS_RAISE) ) + zlog_err ("routing_socket: Can't raise privileges"); + ret = setsockopt(nl->sock, SOL_SOCKET, SO_RCVBUFFORCE, &nl_rcvbufsize, sizeof(nl_rcvbufsize)); + if ( zserv_privs.change (ZPRIVS_LOWER) ) + zlog_err ("routing_socket: Can't lower privileges"); + if (ret < 0) + ret = setsockopt(nl->sock, SOL_SOCKET, SO_RCVBUF, &nl_rcvbufsize, + sizeof(nl_rcvbufsize)); if (ret < 0) { zlog (NULL, LOG_ERR, "Can't set %s receive buffer size: %s", nl->name,