MFC r319369:

 * limit size of buffers to RPC_MAXDATASIZE
 * don't leak memory
 * be more picky about bad parameters

From:

https://raw.githubusercontent.com/guidovranken/rpcbomb/master/libtirpc_patch.txt
https://github.com/guidovranken/rpcbomb/blob/master/rpcbind_patch.txt

via NetBSD.

3 files changed, 22 insertions, 12 deletions

diff --git a/lib/libc/rpc/rpc_generic.c b/lib/libc/rpc/rpc_generic.c
index fe970e1..06faeac 100644
--- a/lib/libc/rpc/rpc_generic.c
+++ b/lib/libc/rpc/rpc_generic.c
@@ -610,6 +610,8 @@ __rpc_taddr2uaddr_af(int af, const struct netbuf *nbuf)
 
 	switch (af) {
 	case AF_INET:
+		if (nbuf->len < sizeof(*sin))
+			return NULL;
 		sin = nbuf->buf;
 		if (inet_ntop(af, &sin->sin_addr, namebuf, sizeof namebuf)
 		    == NULL)
@@ -621,6 +623,8 @@ __rpc_taddr2uaddr_af(int af, const struct netbuf *nbuf)
 		break;
 #ifdef INET6
 	case AF_INET6:
+		if (nbuf->len < sizeof(*sin6))
+			return NULL;
 		sin6 = nbuf->buf;
 		if (inet_ntop(af, &sin6->sin6_addr, namebuf6, sizeof namebuf6)
 		    == NULL)
@@ -659,6 +663,10 @@ __rpc_uaddr2taddr_af(int af, const char *uaddr)
 
 	port = 0;
 	sin = NULL;
+
+	if (uaddr == NULL)
+		return NULL;
+
 	addrstr = strdup(uaddr);
 	if (addrstr == NULL)
 		return NULL;
diff --git a/lib/libc/rpc/rpcb_prot.c b/lib/libc/rpc/rpcb_prot.c
index c462e19..39a201c 100644
--- a/lib/libc/rpc/rpcb_prot.c
+++ b/lib/libc/rpc/rpcb_prot.c
@@ -51,6 +51,7 @@ __FBSDID("$FreeBSD$");
 #include <rpc/types.h>
 #include <rpc/xdr.h>
 #include <rpc/rpcb_prot.h>
+#include <rpc/rpc_com.h>
 #include "un-namespace.h"
 
 bool_t
@@ -62,13 +63,13 @@ xdr_rpcb(XDR *xdrs, RPCB *objp)
 	if (!xdr_rpcvers(xdrs, &objp->r_vers)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_netid, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_addr, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_addr, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_owner, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_owner, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	return (TRUE);
@@ -162,19 +163,19 @@ xdr_rpcblist(XDR *xdrs, RPCBLIST **rp)
 bool_t
 xdr_rpcb_entry(XDR *xdrs, rpcb_entry *objp)
 {
-	if (!xdr_string(xdrs, &objp->r_maddr, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_maddr, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_nc_netid, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_nc_netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	if (!xdr_u_int32_t(xdrs, &objp->r_nc_semantics)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_nc_protofmly, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_nc_protofmly, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->r_nc_proto, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->r_nc_proto, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	return (TRUE);
@@ -289,7 +290,7 @@ xdr_rpcb_rmtcallres(XDR *xdrs, struct rpcb_rmtcallres *p)
 	bool_t dummy;
 	struct r_rpcb_rmtcallres *objp = (struct r_rpcb_rmtcallres *)(void *)p;
 
-	if (!xdr_string(xdrs, &objp->addr, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->addr, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	if (!xdr_u_int(xdrs, &objp->results.results_len)) {
diff --git a/lib/libc/rpc/rpcb_st_xdr.c b/lib/libc/rpc/rpcb_st_xdr.c
index 9abc028..362184e 100644
--- a/lib/libc/rpc/rpcb_st_xdr.c
+++ b/lib/libc/rpc/rpcb_st_xdr.c
@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 
 #include "namespace.h"
 #include <rpc/rpc.h>
+#include <rpc/rpc_com.h>
 #include "un-namespace.h"
 
 /* Link list of all the stats about getport and getaddr */
@@ -63,7 +64,7 @@ xdr_rpcbs_addrlist(XDR *xdrs, rpcbs_addrlist *objp)
 	    if (!xdr_int(xdrs, &objp->failure)) {
 		return (FALSE);
 	    }
-	    if (!xdr_string(xdrs, &objp->netid, (u_int)~0)) {
+	    if (!xdr_string(xdrs, &objp->netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	    }
 
@@ -115,7 +116,7 @@ xdr_rpcbs_rmtcalllist(XDR *xdrs, rpcbs_rmtcalllist *objp)
 		IXDR_PUT_INT32(buf, objp->failure);
 		IXDR_PUT_INT32(buf, objp->indirect);
 	}
-	if (!xdr_string(xdrs, &objp->netid, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	pnext = &objp->next;
@@ -154,7 +155,7 @@ xdr_rpcbs_rmtcalllist(XDR *xdrs, rpcbs_rmtcalllist *objp)
 		objp->failure = (int)IXDR_GET_INT32(buf);
 		objp->indirect = (int)IXDR_GET_INT32(buf);
 	}
-	if (!xdr_string(xdrs, &objp->netid, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	if (!xdr_pointer(xdrs, (char **) pnext,
@@ -182,7 +183,7 @@ xdr_rpcbs_rmtcalllist(XDR *xdrs, rpcbs_rmtcalllist *objp)
 	if (!xdr_int(xdrs, &objp->indirect)) {
 		return (FALSE);
 	}
-	if (!xdr_string(xdrs, &objp->netid, (u_int)~0)) {
+	if (!xdr_string(xdrs, &objp->netid, RPC_MAXDATASIZE)) {
 		return (FALSE);
 	}
 	if (!xdr_pointer(xdrs, (char **) pnext,