Fix the krpc so that it can handle NFSv3,UDP mounts with a read/write

data size greater than 8192. Since soreserve(so, 256*1024, 256*1024)
would always fail for the default value of sb_max, modify clnt_dg.c
so that it uses the calculated values and checks for an error return
from soreserve(). Also, add a check for error return from soreserve()
to clnt_vc.c and change __rpc_get_t_size() to use sb_max_adj instead of
the bogus maxsize == 256*1024.

PR:		kern/150910
Reviewed by:	jhb
MFC after:	2 weeks

3 files changed, 20 insertions, 7 deletions

diff --git a/sys/rpc/clnt_dg.c b/sys/rpc/clnt_dg.c
index e3fa02c..a01f598 100644
--- a/sys/rpc/clnt_dg.c
+++ b/sys/rpc/clnt_dg.c
@@ -193,6 +193,7 @@ clnt_dg_create(
 	struct rpc_msg call_msg;
 	struct __rpc_sockinfo si;
 	XDR xdrs;
+	int error;
 
 	if (svcaddr == NULL) {
 		rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
@@ -267,7 +268,12 @@ clnt_dg_create(
 	 */
 	cu->cu_closeit = FALSE;
 	cu->cu_socket = so;
-	soreserve(so, 256*1024, 256*1024);
+	error = soreserve(so, (u_long)sendsz, (u_long)recvsz);
+	if (error != 0) {
+		rpc_createerr.cf_stat = RPC_FAILED;
+		rpc_createerr.cf_error.re_errno = error;
+		goto err2;
+	}
 
 	sb = &so->so_rcv;
 	SOCKBUF_LOCK(&so->so_rcv);
diff --git a/sys/rpc/clnt_vc.c b/sys/rpc/clnt_vc.c
index 2e5fe41..9699a8d 100644
--- a/sys/rpc/clnt_vc.c
+++ b/sys/rpc/clnt_vc.c
@@ -288,13 +288,19 @@ clnt_vc_create(
 	 * Create a client handle which uses xdrrec for serialization
 	 * and authnone for authentication.
 	 */
+	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
+	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
+	error = soreserve(ct->ct_socket, sendsz, recvsz);
+	if (error != 0) {
+		if (ct->ct_closeit) {
+			soclose(ct->ct_socket);
+		}
+		goto err;
+	}
 	cl->cl_refs = 1;
 	cl->cl_ops = &clnt_vc_ops;
 	cl->cl_private = ct;
 	cl->cl_auth = authnone_create();
-	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
-	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
-	soreserve(ct->ct_socket, sendsz, recvsz);
 
 	SOCKBUF_LOCK(&ct->ct_socket->so_rcv);
 	soupcall_set(ct->ct_socket, SO_RCV, clnt_vc_soupcall, ct);
diff --git a/sys/rpc/rpc_generic.c b/sys/rpc/rpc_generic.c
index efc0cb0..1c6aa82 100644
--- a/sys/rpc/rpc_generic.c
+++ b/sys/rpc/rpc_generic.c
@@ -63,6 +63,8 @@ __FBSDID("$FreeBSD$");
 
 #include <rpc/rpc_com.h>
 
+extern	u_long sb_max_adj;	/* not defined in socketvar.h */
+
 #if __FreeBSD_version < 700000
 #define strrchr rindex
 #endif
@@ -113,9 +115,8 @@ u_int
 /*ARGSUSED*/
 __rpc_get_t_size(int af, int proto, int size)
 {
-	int maxsize, defsize;
+	int defsize;
 
-	maxsize = 256 * 1024;	/* XXX */
 	switch (proto) {
 	case IPPROTO_TCP:
 		defsize = 64 * 1024;	/* XXX */
@@ -131,7 +132,7 @@ __rpc_get_t_size(int af, int proto, int size)
 		return defsize;
 
 	/* Check whether the value is within the upper max limit */
-	return (size > maxsize ? (u_int)maxsize : (u_int)size);
+	return (size > sb_max_adj ? (u_int)sb_max_adj : (u_int)size);
 }
 
 /*