From fc6ef05c8579a313461139e1c31130e0893c56f0 Mon Sep 17 00:00:00 2001

From: Phil Sutter <psutter@redhat.com>

Date: Thu, 18 Feb 2016 14:06:06 +0100

Subject: [PATCH] libnetlink: add size argument to rtnl_talk

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1288042

Upstream Status: iproute2.git commit c079e121a73af

Conflicts:

- Already applied commit d25ec03e1dce4

  ("ipaddress: fix ipaddr_flush for Linux >= 3.1").

- Missing commit 025fa9dc7a4fe

  ("xfrm: add command for configuring SPD hash table").

- Upstream conflict merge at 03371c7d98d16.

commit c079e121a73af5eb49e003b13607e8a690331df6

Author: Stephen Hemminger <shemming@brocade.com>

Date:   Wed May 27 12:26:14 2015 -0700

    libnetlink: add size argument to rtnl_talk

    There have been several instances where response from kernel

    has overrun the stack buffer from the caller. Avoid future problems

    by passing a size argument.

    Also drop the unused peer and group arguments to rtnl_talk.

---

 bridge/fdb.c         |  2 +-

 bridge/link.c        |  2 +-

 bridge/mdb.c         |  2 +-

 bridge/vlan.c        |  2 +-

 genl/ctrl.c          |  4 ++--

 include/libnetlink.h |  4 ++--

 ip/ipaddress.c       |  4 ++--

 ip/ipaddrlabel.c     |  4 ++--

 ip/ipl2tp.c          |  8 ++++----

 ip/iplink.c          | 13 ++++++++-----

 ip/ipneigh.c         |  2 +-

 ip/ipnetns.c         |  4 ++--

 ip/ipntable.c        |  2 +-

 ip/iproute.c         |  8 ++++----

 ip/iprule.c          |  4 ++--

 ip/iptoken.c         |  2 +-

 ip/link_gre.c        |  2 +-

 ip/link_gre6.c       |  2 +-

 ip/link_ip6tnl.c     |  2 +-

 ip/link_iptnl.c      |  2 +-

 ip/link_vti.c        |  2 +-

 ip/link_vti6.c       |  2 +-

 ip/tcp_metrics.c     |  4 ++--

 ip/xfrm_policy.c     | 14 +++++++-------

 ip/xfrm_state.c      | 12 ++++++------

 lib/libgenl.c        |  2 +-

 lib/libnetlink.c     | 40 ++++++++++++++++++++++------------------

 tc/m_action.c        |  6 +++---

 tc/tc_class.c        |  2 +-

 tc/tc_filter.c       |  2 +-

 tc/tc_qdisc.c        |  2 +-

 31 files changed, 85 insertions(+), 78 deletions(-)

diff --git a/bridge/fdb.c b/bridge/fdb.c

index b8138cb..6dc3153 100644

--- a/bridge/fdb.c

+++ b/bridge/fdb.c

@@ -329,7 +329,7 @@ static int fdb_modify(int cmd, int flags, int argc, char **argv)

 		return -1;

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -1;

 	return 0;

diff --git a/bridge/link.c b/bridge/link.c

index c5e7ae5..02777d6 100644

--- a/bridge/link.c

+++ b/bridge/link.c

@@ -376,7 +376,7 @@ static int brlink_modify(int argc, char **argv)

 		addattr_nest_end(&req.n, nest);

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -1;

 	return 0;

diff --git a/bridge/mdb.c b/bridge/mdb.c

index ab3a792..821f575 100644

--- a/bridge/mdb.c

+++ b/bridge/mdb.c

@@ -224,7 +224,7 @@ static int mdb_modify(int cmd, int flags, int argc, char **argv)

 	addattr_l(&req.n, sizeof(req), MDBA_SET_ENTRY, &entry, sizeof(entry));

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -1;

 	return 0;

diff --git a/bridge/vlan.c b/bridge/vlan.c

index ba54b0e..b471bf7 100644

--- a/bridge/vlan.c

+++ b/bridge/vlan.c

@@ -95,7 +95,7 @@ static int vlan_modify(int cmd, int argc, char **argv)

 	addattr_nest_end(&req.n, afspec);

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -1;

 	return 0;

diff --git a/genl/ctrl.c b/genl/ctrl.c

index 48cbc35..2596883 100644

--- a/genl/ctrl.c

+++ b/genl/ctrl.c

@@ -67,7 +67,7 @@ int genl_ctrl_resolve_family(const char *family)

 	addattr_l(nlh, 128, CTRL_ATTR_FAMILY_NAME, family, strlen(family) + 1);

-	if (rtnl_talk(&rth, nlh, 0, 0, nlh) < 0) {

+	if (rtnl_talk(&rth, nlh, nlh, sizeof(req)) < 0) {

 		fprintf(stderr, "Error talking to the kernel\n");

 		goto errout;

 	}

@@ -341,7 +341,7 @@ static int ctrl_list(int cmd, int argc, char **argv)

 			goto ctrl_done;

 		}

-		if (rtnl_talk(&rth, nlh, 0, 0, nlh) < 0) {

+		if (rtnl_talk(&rth, nlh, nlh, sizeof(req)) < 0) {

 			fprintf(stderr, "Error talking to the kernel\n");

 			goto ctrl_done;

 		}

diff --git a/include/libnetlink.h b/include/libnetlink.h

index 058dc64..8c90873 100644

--- a/include/libnetlink.h

+++ b/include/libnetlink.h

@@ -68,8 +68,8 @@ int rtnl_dump_filter_nc(struct rtnl_handle *rth,

 			void *arg, __u16 nc_flags);

 #define rtnl_dump_filter(rth, filter, arg) \

 	rtnl_dump_filter_nc(rth, filter, arg, 0)

-extern int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

-		     unsigned groups, struct nlmsghdr *answer)

+extern int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,

+		     struct nlmsghdr *answer, size_t len)

 	__attribute__((warn_unused_result));

 extern int rtnl_send(struct rtnl_handle *rth, const void *buf, int)

 	__attribute__((warn_unused_result));

diff --git a/ip/ipaddress.c b/ip/ipaddress.c

index f5a47db..700c40f 100644

--- a/ip/ipaddress.c

+++ b/ip/ipaddress.c

@@ -1024,7 +1024,7 @@ static int restore_handler(const struct sockaddr_nl *nl,

 	ll_init_map(&rth);

-	ret = rtnl_talk(&rth, n, 0, 0, n);

+	ret = rtnl_talk(&rth, n, n, sizeof(*n));

 	if ((ret < 0) && (errno == EEXIST))

 		ret = 0;

@@ -1587,7 +1587,7 @@ static int ipaddr_modify(int cmd, int flags, int argc, char **argv)

 			  sizeof(cinfo));

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

diff --git a/ip/ipaddrlabel.c b/ip/ipaddrlabel.c

index 5b1f6e4..c5d69f4 100644

--- a/ip/ipaddrlabel.c

+++ b/ip/ipaddrlabel.c

@@ -183,7 +183,7 @@ static int ipaddrlabel_modify(int cmd, int argc, char **argv)

 	if (req.ifal.ifal_family == AF_UNSPEC)

 		req.ifal.ifal_family = AF_INET6;

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -210,7 +210,7 @@ static int flush_addrlabel(const struct sockaddr_nl *who, struct nlmsghdr *n, vo

 		if (rtnl_open(&rth2, 0) < 0)

 			return -1;

-		if (rtnl_talk(&rth2, n, 0, 0, NULL) < 0)

+		if (rtnl_talk(&rth2, n, NULL, 0) < 0)

 			return -2;

 		rtnl_close(&rth2;;

diff --git a/ip/ipl2tp.c b/ip/ipl2tp.c

index 5cd8632..2f7c9bf 100644

--- a/ip/ipl2tp.c

+++ b/ip/ipl2tp.c

@@ -119,7 +119,7 @@ static int create_tunnel(struct l2tp_parm *p)

 		addattr16(&req.n, 1024, L2TP_ATTR_UDP_DPORT, p->peer_udp_port);

 	}

-	if (rtnl_talk(&genl_rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&genl_rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -132,7 +132,7 @@ static int delete_tunnel(struct l2tp_parm *p)

 	addattr32(&req.n, 128, L2TP_ATTR_CONN_ID, p->tunnel_id);

-	if (rtnl_talk(&genl_rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&genl_rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -166,7 +166,7 @@ static int create_session(struct l2tp_parm *p)

 	if (p->ifname && p->ifname[0])

 		addattrstrz(&req.n, 1024, L2TP_ATTR_IFNAME, p->ifname);

-	if (rtnl_talk(&genl_rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&genl_rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -179,7 +179,7 @@ static int delete_session(struct l2tp_parm *p)

 	addattr32(&req.n, 1024, L2TP_ATTR_CONN_ID, p->tunnel_id);

 	addattr32(&req.n, 1024, L2TP_ATTR_SESSION_ID, p->session_id);

-	if (rtnl_talk(&genl_rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&genl_rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

diff --git a/ip/iplink.c b/ip/iplink.c

index 9362e83..048d4f3 100644

--- a/ip/iplink.c

+++ b/ip/iplink.c

@@ -592,7 +592,7 @@ static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv)

 			req.i.ifi_index = 0;

 			addattr32(&req.n, sizeof(req), IFLA_GROUP, group);

-			if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+			if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 				exit(2);

 			return 0;

 		}

@@ -667,7 +667,7 @@ static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv)

 		return -1;

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	return 0;

@@ -677,7 +677,10 @@ int iplink_get(unsigned int flags, char *name, __u32 filt_mask)

 {

 	int len;

 	struct iplink_req req;

-	char answer[16384];

+	struct {

+		struct nlmsghdr n;

+		char buf[16384];

+	} answer;

 	memset(&req, 0, sizeof(req));

@@ -697,10 +700,10 @@ int iplink_get(unsigned int flags, char *name, __u32 filt_mask)

 	}

 	addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask);

-	if (rtnl_talk(&rth, &req.n, 0, 0, (struct nlmsghdr *)answer) < 0)

+	if (rtnl_talk(&rth, &req.n, &answer.n, sizeof(answer)) < 0)

 		return -2;

-	print_linkinfo(NULL, (struct nlmsghdr *)answer, stdout);

+	print_linkinfo(NULL, &answer.n, stdout);

 	return 0;

 }

diff --git a/ip/ipneigh.c b/ip/ipneigh.c

index c47f005..19fd8e2 100644

--- a/ip/ipneigh.c

+++ b/ip/ipneigh.c

@@ -179,7 +179,7 @@ static int ipneigh_modify(int cmd, int flags, int argc, char **argv)

 		return -1;

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	return 0;

diff --git a/ip/ipnetns.c b/ip/ipnetns.c

index 00b6cc4..2c848bc 100644

--- a/ip/ipnetns.c

+++ b/ip/ipnetns.c

@@ -113,7 +113,7 @@ static int get_netnsid_from_name(const char *name)

 		return fd;

 	addattr32(&req.n, 1024, NETNSA_FD, fd);

-	if (rtnl_talk(&rtnsh, &req.n, 0, 0, &answer.n) < 0) {

+	if (rtnl_talk(&rtnsh, &req.n, &answer.n, sizeof(answer)) < 0) {

 		close(fd);

 		return -2;

 	}

@@ -698,7 +698,7 @@ static int set_netnsid_from_name(const char *name, int nsid)

 	addattr32(&req.n, 1024, NETNSA_FD, fd);

 	addattr32(&req.n, 1024, NETNSA_NSID, nsid);

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		err = -2;

 	close(fd);

diff --git a/ip/ipntable.c b/ip/ipntable.c

index 4d4eece..ca5d935 100644

--- a/ip/ipntable.c

+++ b/ip/ipntable.c

@@ -314,7 +314,7 @@ static int ipntable_modify(int cmd, int flags, int argc, char **argv)

 			  RTA_PAYLOAD(parms_rta));

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	return 0;

diff --git a/ip/iproute.c b/ip/iproute.c

index 4f7cd9b..367b922 100644

--- a/ip/iproute.c

+++ b/ip/iproute.c

@@ -1029,7 +1029,7 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)

 	if (req.r.rtm_family == AF_UNSPEC)

 		req.r.rtm_family = AF_INET;

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -1486,7 +1486,7 @@ static int iproute_get(int argc, char **argv)

 	if (req.r.rtm_family == AF_UNSPEC)

 		req.r.rtm_family = AF_INET;

-	if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0)

+	if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0)

 		exit(2);

 	if (connected && !from_ok) {

@@ -1527,7 +1527,7 @@ static int iproute_get(int argc, char **argv)

 		req.n.nlmsg_flags = NLM_F_REQUEST;

 		req.n.nlmsg_type = RTM_GETROUTE;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0)

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0)

 			exit(2);

 	}

@@ -1549,7 +1549,7 @@ static int restore_handler(const struct sockaddr_nl *nl,

 	ll_init_map(&rth);

-	ret = rtnl_talk(&rth, n, 0, 0, n);

+	ret = rtnl_talk(&rth, n, n, sizeof(*n));

 	if ((ret < 0) && (errno == EEXIST))

 		ret = 0;

diff --git a/ip/iprule.c b/ip/iprule.c

index eebcda2..89fa7ef 100644

--- a/ip/iprule.c

+++ b/ip/iprule.c

@@ -354,7 +354,7 @@ static int iprule_modify(int cmd, int argc, char **argv)

 	if (!table_ok && cmd == RTM_NEWRULE)

 		req.r.rtm_table = RT_TABLE_MAIN;

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

@@ -381,7 +381,7 @@ static int flush_rule(const struct sockaddr_nl *who, struct nlmsghdr *n, void *a

 		if (rtnl_open(&rth2, 0) < 0)

 			return -1;

-		if (rtnl_talk(&rth2, n, 0, 0, NULL) < 0)

+		if (rtnl_talk(&rth2, n, NULL, 0) < 0)

 			return -2;

 		rtnl_close(&rth2;;

diff --git a/ip/iptoken.c b/ip/iptoken.c

index 5689c2e..0d265e6 100644

--- a/ip/iptoken.c

+++ b/ip/iptoken.c

@@ -182,7 +182,7 @@ static int iptoken_set(int argc, char **argv)

 		return -1;

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		return -2;

 	return 0;

diff --git a/ip/link_gre.c b/ip/link_gre.c

index ddbd6cc..62acf46 100644

--- a/ip/link_gre.c

+++ b/ip/link_gre.c

@@ -77,7 +77,7 @@ static int gre_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/link_gre6.c b/ip/link_gre6.c

index f18919c..e00ea09 100644

--- a/ip/link_gre6.c

+++ b/ip/link_gre6.c

@@ -91,7 +91,7 @@ static int gre_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/link_ip6tnl.c b/ip/link_ip6tnl.c

index cf59a93..f771c75 100644

--- a/ip/link_ip6tnl.c

+++ b/ip/link_ip6tnl.c

@@ -89,7 +89,7 @@ static int ip6tunnel_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/link_iptnl.c b/ip/link_iptnl.c

index 2ac2604..4d5422b 100644

--- a/ip/link_iptnl.c

+++ b/ip/link_iptnl.c

@@ -81,7 +81,7 @@ static int iptunnel_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/link_vti.c b/ip/link_vti.c

index 59ac4c4..f3fea33 100644

--- a/ip/link_vti.c

+++ b/ip/link_vti.c

@@ -71,7 +71,7 @@ static int vti_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/link_vti6.c b/ip/link_vti6.c

index 282896d..c146f79 100644

--- a/ip/link_vti6.c

+++ b/ip/link_vti6.c

@@ -67,7 +67,7 @@ static int vti6_parse_opt(struct link_util *lu, int argc, char **argv,

 		req.i.ifi_family = preferred_family;

 		req.i.ifi_index = ifi->ifi_index;

-		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {

+		if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {

 get_failed:

 			fprintf(stderr,

 				"Failed to get existing tunnel info.\n");

diff --git a/ip/tcp_metrics.c b/ip/tcp_metrics.c

index c6be3c9..8fa4b26 100644

--- a/ip/tcp_metrics.c

+++ b/ip/tcp_metrics.c

@@ -386,10 +386,10 @@ static int tcpm_do_cmd(int cmd, int argc, char **argv)

 	}

 	if (ack) {

-		if (rtnl_talk(&grth, &req.n, 0, 0, NULL) < 0)

+		if (rtnl_talk(&grth, &req.n, NULL, 0) < 0)

 			return -2;

 	} else if (atype >= 0) {

-		if (rtnl_talk(&grth, &req.n, 0, 0, &req.n) < 0)

+		if (rtnl_talk(&grth, &req.n, &req.n, sizeof(req)) < 0)

 			return -2;

 		if (process_msg(NULL, &req.n, stdout) < 0) {

 			fprintf(stderr, "Dump terminated\n");

diff --git a/ip/xfrm_policy.c b/ip/xfrm_policy.c

index f7f2c5c..3ff734e 100644

--- a/ip/xfrm_policy.c

+++ b/ip/xfrm_policy.c

@@ -393,7 +393,7 @@ static int xfrm_policy_modify(int cmd, unsigned flags, int argc, char **argv)

 	if (req.xpinfo.sel.family == AF_UNSPEC)

 		req.xpinfo.sel.family = AF_INET;

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	rtnl_close(&rth);

@@ -555,7 +555,7 @@ int xfrm_policy_print(const struct sockaddr_nl *who, struct nlmsghdr *n,

 }

 static int xfrm_policy_get_or_delete(int argc, char **argv, int delete,

-				     void *res_nlbuf)

+				     void *res_nlbuf, size_t res_size)

 {

 	struct rtnl_handle rth;

 	struct {

@@ -670,7 +670,7 @@ static int xfrm_policy_get_or_delete(int argc, char **argv, int delete,

 			  (void *)&ctx, ctx.sctx.len);

 	}

-	if (rtnl_talk(&rth, &req.n, 0, 0, res_nlbuf) < 0)

+	if (rtnl_talk(&rth, &req.n, res_nlbuf, res_size) < 0)

 		exit(2);

 	rtnl_close(&rth);

@@ -680,7 +680,7 @@ static int xfrm_policy_get_or_delete(int argc, char **argv, int delete,

 static int xfrm_policy_delete(int argc, char **argv)

 {

-	return xfrm_policy_get_or_delete(argc, argv, 1, NULL);

+	return xfrm_policy_get_or_delete(argc, argv, 1, NULL, 0);

 }

 static int xfrm_policy_get(int argc, char **argv)

@@ -690,7 +690,7 @@ static int xfrm_policy_get(int argc, char **argv)

 	memset(buf, 0, sizeof(buf));

-	xfrm_policy_get_or_delete(argc, argv, 0, n);

+	xfrm_policy_get_or_delete(argc, argv, 0, n, sizeof(buf));

 	if (xfrm_policy_print(NULL, n, (void*)stdout) < 0) {

 		fprintf(stderr, "An error :-)\n");

@@ -975,7 +975,7 @@ static int xfrm_spd_getinfo(int argc, char **argv)

 	if (rtnl_open_byproto(&rth, 0, NETLINK_XFRM) < 0)

 		exit(1);

-	if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0)

+	if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0)

 		exit(2);

 	print_spdinfo(&req.n, (void*)stdout);

@@ -1027,7 +1027,7 @@ static int xfrm_policy_flush(int argc, char **argv)

 	if (show_stats > 1)

 		fprintf(stderr, "Flush policy\n");

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	rtnl_close(&rth);

diff --git a/ip/xfrm_state.c b/ip/xfrm_state.c

index 0f6b10d..20d7a7e 100644

--- a/ip/xfrm_state.c

+++ b/ip/xfrm_state.c

@@ -644,7 +644,7 @@ static int xfrm_state_modify(int cmd, unsigned flags, int argc, char **argv)

 	if (req.xsinfo.family == AF_UNSPEC)

 		req.xsinfo.family = AF_INET;

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	rtnl_close(&rth);

@@ -781,7 +781,7 @@ static int xfrm_state_allocspi(int argc, char **argv)

 		req.xspi.info.family = AF_INET;

-	if (rtnl_talk(&rth, &req.n, 0, 0, res_n) < 0)

+	if (rtnl_talk(&rth, &req.n, res_n, sizeof(res_buf)) < 0)

 		exit(2);

 	if (xfrm_state_print(NULL, res_n, (void*)stdout) < 0) {

@@ -971,7 +971,7 @@ static int xfrm_state_get_or_delete(int argc, char **argv, int delete)

 		req.xsid.family = AF_INET;

 	if (delete) {

-		if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+		if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 			exit(2);

 	} else {

 		char buf[NLMSG_BUF_SIZE];

@@ -979,7 +979,7 @@ static int xfrm_state_get_or_delete(int argc, char **argv, int delete)

 		memset(buf, 0, sizeof(buf));

-		if (rtnl_talk(&rth, &req.n, 0, 0, res_n) < 0)

+		if (rtnl_talk(&rth, &req.n, res_n, sizeof(req)) < 0)

 			exit(2);

 		if (xfrm_state_print(NULL, res_n, (void*)stdout) < 0) {

@@ -1220,7 +1220,7 @@ static int xfrm_sad_getinfo(int argc, char **argv)

 	if (rtnl_open_byproto(&rth, 0, NETLINK_XFRM) < 0)

 		exit(1);

-	if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0)

+	if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0)

 		exit(2);

 	print_sadinfo(&req.n, (void*)stdout);

@@ -1274,7 +1274,7 @@ static int xfrm_state_flush(int argc, char **argv)

 		fprintf(stderr, "Flush state with XFRM-PROTO value \"%s\"\n",

 			strxf_xfrmproto(req.xsf.proto));

-	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0)

+	if (rtnl_talk(&rth, &req.n, NULL, 0) < 0)

 		exit(2);

 	rtnl_close(&rth);

diff --git a/lib/libgenl.c b/lib/libgenl.c

index ef3e5db..acb1478 100644

--- a/lib/libgenl.c

+++ b/lib/libgenl.c

@@ -53,7 +53,7 @@ int genl_resolve_family(struct rtnl_handle *grth, const char *family)

 	addattr_l(&req.n, sizeof(req), CTRL_ATTR_FAMILY_NAME,

 		  family, strlen(family) + 1);

-	if (rtnl_talk(grth, &req.n, 0, 0, &req.n) < 0) {

+	if (rtnl_talk(grth, &req.n, &req.n, sizeof(req)) < 0) {

 		fprintf(stderr, "Error talking to the kernel\n");

 		return -2;

 	}

diff --git a/lib/libnetlink.c b/lib/libnetlink.c

index 95675be..97b79fd 100644

--- a/lib/libnetlink.c

+++ b/lib/libnetlink.c

@@ -29,6 +29,10 @@

 #define SOL_NETLINK 270

 #endif

+#ifndef MIN

+#define MIN(a, b) ((a) < (b) ? (a) : (b))

+#endif

+

 int rcvbuf = 1024 * 1024;

 void rtnl_close(struct rtnl_handle *rth)

@@ -306,8 +310,8 @@ int rtnl_dump_filter_nc(struct rtnl_handle *rth,

 	return rtnl_dump_filter_l(rth, a);

 }

-int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

-	      unsigned groups, struct nlmsghdr *answer)

+int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,

+	      struct nlmsghdr *answer, size_t len)

 {

 	int status;

 	unsigned seq;

@@ -323,12 +327,10 @@ int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

 		.msg_iov = &iov,

 		.msg_iovlen = 1,

 	};

-	char   buf[16384];

+	char   buf[32768];

 	memset(&nladdr, 0, sizeof(nladdr));

 	nladdr.nl_family = AF_NETLINK;

-	nladdr.nl_pid = peer;

-	nladdr.nl_groups = groups;

 	n->nlmsg_seq = seq = ++rtnl->seq;

@@ -336,7 +338,6 @@ int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

 		n->nlmsg_flags |= NLM_F_ACK;

 	status = sendmsg(rtnl->fd, &msg, 0);

-

 	if (status < 0) {

 		perror("Cannot talk to rtnetlink");

 		return -1;

@@ -345,7 +346,6 @@ int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

 	memset(buf,0,sizeof(buf));

 	iov.iov_base = buf;

-

 	while (1) {

 		iov.iov_len = sizeof(buf);

 		status = recvmsg(rtnl->fd, &msg, 0);

@@ -378,7 +378,7 @@ int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

 				exit(1);

 			}

-			if (nladdr.nl_pid != peer ||

+			if (nladdr.nl_pid != 0 ||

 			    h->nlmsg_pid != rtnl->local.nl_pid ||

 			    h->nlmsg_seq != seq) {

 				/* Don't forget to skip that message. */

@@ -391,20 +391,22 @@ int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n, pid_t peer,

 				struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);

 				if (l < sizeof(struct nlmsgerr)) {

 					fprintf(stderr, "ERROR truncated\n");

-				} else {

-					if (!err->error) {

-						if (answer)

-							memcpy(answer, h, h->nlmsg_len);

-						return 0;

-					}

-

-					fprintf(stderr, "RTNETLINK answers: %s\n", strerror(-err->error));

-					errno = -err->error;

+				} else if (!err->error) {

+					if (answer)

+						memcpy(answer, h,

+						       MIN(len, h->nlmsg_len));

+					return 0;

 				}