Wire the sysctl output buffer before grabbing any locks to prevent

SYSCTL_OUT() from blocking while locks are held.  This should
only be done when it would be inconvenient to make a temporary copy of
the data and defer calling SYSCTL_OUT() until after the locks are
released.

3 files changed, 9 insertions, 0 deletions

diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index c2799d5..0c4b385 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -841,6 +841,9 @@ tcp_pcblist(SYSCTL_HANDLER_ARGS)
 	INP_INFO_RUNLOCK(&tcbinfo);
 	splx(s);
 
+	sysctl_wire_old_buffer(req, 2 * (sizeof xig)
+		+ n * sizeof(struct xtcpcb));
+
 	xig.xig_len = sizeof xig;
 	xig.xig_count = n;
 	xig.xig_gen = gencnt;
diff --git a/sys/netinet/tcp_timewait.c b/sys/netinet/tcp_timewait.c
index c2799d5..0c4b385 100644
--- a/sys/netinet/tcp_timewait.c
+++ b/sys/netinet/tcp_timewait.c
@@ -841,6 +841,9 @@ tcp_pcblist(SYSCTL_HANDLER_ARGS)
 	INP_INFO_RUNLOCK(&tcbinfo);
 	splx(s);
 
+	sysctl_wire_old_buffer(req, 2 * (sizeof xig)
+		+ n * sizeof(struct xtcpcb));
+
 	xig.xig_len = sizeof xig;
 	xig.xig_count = n;
 	xig.xig_gen = gencnt;
diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index 56bb1e1..b93e99e 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -598,6 +598,9 @@ udp_pcblist(SYSCTL_HANDLER_ARGS)
 	n = udbinfo.ipi_count;
 	splx(s);
 
+	sysctl_wire_old_buffer(req, 2 * (sizeof xig)
+		+ n * sizeof(struct xinpcb));
+
 	xig.xig_len = sizeof xig;
 	xig.xig_count = n;
 	xig.xig_gen = gencnt;