Hide the unfortunate named sysctl kern.ipc.somaxconn from sysctl -a

output and replace it with a new visible sysctl kern.ipc.acceptqueue
of the same functionality.  It specifies the maximum length of the
accept queue on a listen socket.

The old kern.ipc.somaxconn remains available for reading and writing
for compatibility reasons so that existing programs, scripts and
configurations continue to work.  There no plans to ever remove the
orginal and now hidden kern.ipc.somaxconn.

1 files changed, 7 insertions, 1 deletions

diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 6b5581f..a964cf2 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -185,6 +185,8 @@ MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
 /*
  * Limit on the number of connections in the listen queue waiting
  * for accept(2).
+ * NB: The orginal sysctl somaxconn is still available but hidden
+ * to prevent confusion about the actually purpose of this number.
  */
 static int somaxconn = SOMAXCONN;
 
@@ -205,9 +207,13 @@ sysctl_somaxconn(SYSCTL_HANDLER_ARGS)
 	somaxconn = val;
 	return (0);
 }
-SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLTYPE_UINT | CTLFLAG_RW,
+SYSCTL_PROC(_kern_ipc, OID_AUTO, soacceptqueue, CTLTYPE_UINT | CTLFLAG_RW,
     0, sizeof(int), sysctl_somaxconn, "I",
     "Maximum listen socket pending connection accept queue size");
+SYSCTL_PROC(_kern_ipc, KIPC_SOMAXCONN, somaxconn,
+    CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_SKIP,
+    0, sizeof(int), sysctl_somaxconn, "I",
+    "Maximum listen socket pending connection accept queue size (compat)");
 
 static int numopensockets;
 SYSCTL_INT(_kern_ipc, OID_AUTO, numopensockets, CTLFLAG_RD,