From 1a47c83cc1e59314c318f29b7cec49a58c6d1af8 Mon Sep 17 00:00:00 2001

From: Phil Sutter <psutter@redhat.com>

Date: Wed, 17 Feb 2016 14:03:59 +0100

Subject: [PATCH] ipaddress: fix ipaddr_flush for Linux >= 3.1

This is a combination of 3 commits:

commit 8e72880f6bfa39f439b9c4a88eb84b635b991687

Author: Phil Sutter <phil@nwl.cc>

Date:   Tue Nov 24 15:31:01 2015 +0100

    libnetlink: introduce nc_flags

    Allow for a filter to ignore certain nlmsg_flags.

    Signed-off-by: Phil Sutter <phil@nwl.cc>

commit c6995c48025233902a5b0c5fe88654e17ea934f6

Author: Phil Sutter <phil@nwl.cc>

Date:   Tue Nov 24 15:31:00 2015 +0100

    ipaddress: simplify ipaddr_flush()

    Since it's no longer relevant whether an IP address is primary or

    secondary when flushing, ipaddr_flush() can be simplified a bit.

    Signed-off-by: Phil Sutter <phil@nwl.cc>

commit d25ec03e1dce4cf22093a9f7106e9401ab5bf066

Author: Phil Sutter <phil@nwl.cc>

Date:   Tue Nov 24 15:31:02 2015 +0100

    ipaddress: fix ipaddr_flush for Linux >= 3.1

    Linux version 3.1 introduced a consistency check for netlink dumps in

    commit 670dc28 ("netlink: advertise incomplete dumps"). This bites

    iproute2 when flushing more addresses than can fit into a single

    RTM_GETADDR response. To silence the spurious error message "Dump was

    interrupted and may be inconsistent.", advise rtnl_dump_filter_l() to

    not care about NLM_F_DUMP_INTR.

    Signed-off-by: Phil Sutter <phil@nwl.cc>

---

 include/libnetlink.h |  8 ++++++--

 ip/ipaddress.c       | 39 ++-------------------------------------

 lib/libnetlink.c     | 10 ++++++----

 3 files changed, 14 insertions(+), 43 deletions(-)

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

index 95f41d979828f..b008b93f4e65e 100644

--- a/include/libnetlink.h

+++ b/include/libnetlink.h

@@ -48,12 +48,16 @@ struct rtnl_dump_filter_arg

 {

 	rtnl_filter_t filter;

 	void *arg1;

+	__u16 nc_flags;

 };

 extern int rtnl_dump_filter_l(struct rtnl_handle *rth,

 			      const struct rtnl_dump_filter_arg *arg);

-extern int rtnl_dump_filter(struct rtnl_handle *rth, rtnl_filter_t filter,

-			    void *arg);

+int rtnl_dump_filter_nc(struct rtnl_handle *rth,

+			rtnl_filter_t filter,

+			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,

 		     struct nlmsghdr *answer, size_t len);

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

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

index 94ff53898a915..533c72c5b1c0f 100644

--- a/ip/ipaddress.c

+++ b/ip/ipaddress.c

@@ -875,28 +875,6 @@ int print_addrinfo(const struct sockaddr_nl *who, struct nlmsghdr *n,

 	return 0;

 }

-static int print_addrinfo_primary(const struct sockaddr_nl *who,

-				  struct nlmsghdr *n, void *arg)

-{

-	struct ifaddrmsg *ifa = NLMSG_DATA(n);

-

-	if (ifa->ifa_flags & IFA_F_SECONDARY)

-		return 0;

-

-	return print_addrinfo(who, n, arg);

-}

-

-static int print_addrinfo_secondary(const struct sockaddr_nl *who,

-				    struct nlmsghdr *n, void *arg)

-{

-	struct ifaddrmsg *ifa = NLMSG_DATA(n);

-

-	if (!(ifa->ifa_flags & IFA_F_SECONDARY))

-		return 0;

-

-	return print_addrinfo(who, n, arg);

-}

-

 struct nlmsg_list

 {

 	struct nlmsg_list *next;

@@ -1139,26 +1117,13 @@ static int ipaddr_flush(void)

 	filter.flushe = sizeof(flushb);

 	while ((max_flush_loops == 0) || (round < max_flush_loops)) {

-		const struct rtnl_dump_filter_arg a[3] = {

-			{

-				.filter = print_addrinfo_secondary,

-				.arg1 = stdout,

-			},

-			{

-				.filter = print_addrinfo_primary,

-				.arg1 = stdout,

-			},

-			{

-				.filter = NULL,

-				.arg1 = NULL,

-			},

-		};

 		if (rtnl_wilddump_request(&rth, filter.family, RTM_GETADDR) < 0) {

 			perror("Cannot send dump request");

 			exit(1);

 		}

 		filter.flushed = 0;

-		if (rtnl_dump_filter_l(&rth, a) < 0) {

+		if (rtnl_dump_filter_nc(&rth, print_addrinfo,

+					stdout, NLM_F_DUMP_INTR) < 0) {

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

 			exit(1);

 		}

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

index c455a41eccfdd..ebe3c120aa96b 100644

--- a/lib/libnetlink.c

+++ b/lib/libnetlink.c

@@ -234,6 +234,8 @@ int rtnl_dump_filter_l(struct rtnl_handle *rth,

 			while (NLMSG_OK(h, msglen)) {

 				int err;

+				h->nlmsg_flags &= ~a->nc_flags;

+

 				if (nladdr.nl_pid != 0 ||

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

 				    h->nlmsg_seq != rth->dump)

@@ -284,13 +286,13 @@ skip_it:

 	}

 }

-int rtnl_dump_filter(struct rtnl_handle *rth,

+int rtnl_dump_filter_nc(struct rtnl_handle *rth,

 		     rtnl_filter_t filter,

-		     void *arg1)

+		     void *arg1, __u16 nc_flags)

 {

 	const struct rtnl_dump_filter_arg a[2] = {

-		{ .filter = filter, .arg1 = arg1, },

-		{ .filter = NULL,   .arg1 = NULL, },

+		{ .filter = filter, .arg1 = arg1, .nc_flags = nc_flags, },

+		{ .filter = NULL,   .arg1 = NULL, .nc_flags = 0, },

 	};

 	return rtnl_dump_filter_l(rth, a);

-- 

2.8.2