diff --git a/SOURCES/0002-msg-peek-by-default-rh1396882.patch b/SOURCES/0002-msg-peek-by-default-rh1396882.patch
new file mode 100644
index 0000000..c4e0b39
--- /dev/null
+++ b/SOURCES/0002-msg-peek-by-default-rh1396882.patch
@@ -0,0 +1,154 @@
+From f7882fef99e90bb2106f0458b407c7914bc87034 Mon Sep 17 00:00:00 2001
+From: Thomas Haller <thaller@redhat.com>
+Date: Wed, 30 Nov 2016 15:09:41 +0100
+Subject: [PATCH 1/1] lib: use MSG_PEEK by default for nl_recvmsgs()
+
+The MSG_PEEK API of recvmsg() should be avoid because it requires an additional
+syscall. But worse is to choose a too small buffer size and failing to receive
+the message.
+
+A user who is aware of the issue can avoid MSG_PEEK by either
+nl_socket_disable_msg_peek()/nl_socket_enable_msg_peek() or by setting
+a buffer size via nl_socket_set_msg_buf_size().
+
+By default however we now use MSG_PEEK. This is more important since commit
+90c6ebec9bd7a where the link dump request can be rather large.
+
+Signed-off-by: Thomas Haller <thaller@redhat.com>
+(cherry picked from commit 55ea6e6b6cd805f441b410971c9dd7575e783ef4)
+---
+ include/netlink-private/types.h | 3 ++-
+ include/netlink/utils.h | 15 +++++++++++++++
+ lib/nl.c | 5 +++--
+ lib/socket.c | 20 +++++++++++++++++++-
+ lib/utils.c | 2 +-
+ 5 files changed, 40 insertions(+), 5 deletions(-)
+
+diff --git a/include/netlink-private/types.h b/include/netlink-private/types.h
+index 0f67ddd..f1467cc 100644
+--- a/include/netlink-private/types.h
++++ b/include/netlink-private/types.h
+@@ -27,7 +27,8 @@
+ #define NL_SOCK_PASSCRED (1<<1)
+ #define NL_OWN_PORT (1<<2)
+ #define NL_MSG_PEEK (1<<3)
+-#define NL_NO_AUTO_ACK (1<<4)
++#define NL_MSG_PEEK_EXPLICIT (1<<4)
++#define NL_NO_AUTO_ACK (1<<5)
+
+ #define NL_MSG_CRED_PRESENT 1
+
+diff --git a/include/netlink/utils.h b/include/netlink/utils.h
+index 1115bb4..2273835 100644
+--- a/include/netlink/utils.h
++++ b/include/netlink/utils.h
+@@ -224,6 +224,21 @@ enum {
+ NL_CAPABILITY_RTNL_ADDR_PEER_ID_FIX = 20,
+ #define NL_CAPABILITY_RTNL_ADDR_PEER_ID_FIX NL_CAPABILITY_RTNL_ADDR_PEER_ID_FIX
+
++ /* Older versions of libnl3 would not use MSG_PEEK for nl_recvmsgs() unless calling
++ * nl_socket_enable_msg_peek(). Instead, the user had to specify the buffer size via
++ * nl_socket_set_msg_buf_size(), which in turn would default to 4*getpagesize().
++ *
++ * The default value might not be large enough, so users who were not aware of the
++ * problem easily ended up using a too small receive buffer. Usually, one wants to
++ * avoid MSG_PEEK for recvmsg() because it requires an additional syscall.
++ *
++ * Now, as indicated by this capability, nl_recvmsgs() would use MSG_PEEK by default. The
++ * user still can explicitly disable MSG_PEEK by calling nl_socket_disable_msg_peek() or
++ * by setting the nl_socket_set_msg_buf_size() to a non-zero value.
++ */
++ NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT = 24,
++#define NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT
++
+ __NL_CAPABILITY_MAX,
+ NL_CAPABILITY_MAX = (__NL_CAPABILITY_MAX - 1),
+ #define NL_CAPABILITY_MAX NL_CAPABILITY_MAX
+diff --git a/lib/nl.c b/lib/nl.c
+index 2d1ce81..8df08e6 100644
+--- a/lib/nl.c
++++ b/lib/nl.c
+@@ -676,7 +676,8 @@ int nl_recv(struct nl_sock *sk, struct sockaddr_nl *nla,
+ if (!buf || !nla)
+ return -NLE_INVAL;
+
+- if (sk->s_flags & NL_MSG_PEEK)
++ if ( (sk->s_flags & NL_MSG_PEEK)
++ || (!(sk->s_flags & NL_MSG_PEEK_EXPLICIT) && sk->s_bufsize == 0))
+ flags |= MSG_PEEK | MSG_TRUNC;
+
+ if (page_size == 0)
+@@ -742,7 +743,7 @@ retry:
+ void *tmp;
+
+ /* respond with error to an incomplete message */
+- if (!(sk->s_flags & NL_MSG_PEEK)) {
++ if (flags == 0) {
+ retval = -NLE_MSG_TRUNC;
+ goto abort;
+ }
+diff --git a/lib/socket.c b/lib/socket.c
+index 109c416..99e1a1b 100644
+--- a/lib/socket.c
++++ b/lib/socket.c
+@@ -722,18 +722,23 @@ int nl_socket_set_nonblocking(const struct nl_sock *sk)
+ /**
+ * Enable use of MSG_PEEK when reading from socket
+ * @arg sk Netlink socket.
++ *
++ * See also NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT capability
+ */
+ void nl_socket_enable_msg_peek(struct nl_sock *sk)
+ {
+- sk->s_flags |= NL_MSG_PEEK;
++ sk->s_flags |= (NL_MSG_PEEK | NL_MSG_PEEK_EXPLICIT);
+ }
+
+ /**
+ * Disable use of MSG_PEEK when reading from socket
+ * @arg sk Netlink socket.
++ *
++ * See also NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT capability
+ */
+ void nl_socket_disable_msg_peek(struct nl_sock *sk)
+ {
++ sk->s_flags |= NL_MSG_PEEK_EXPLICIT;
+ sk->s_flags &= ~NL_MSG_PEEK;
+ }
+
+@@ -853,6 +858,19 @@ int nl_socket_set_buffer_size(struct nl_sock *sk, int rxbuf, int txbuf)
+ * socket will be able to receive. It is generally recommneded to specify
+ * a buffer size no less than the size of a memory page.
+ *
++ * Setting the @bufsize to zero means to use a default of 4 times getpagesize().
++ *
++ * When MSG_PEEK is enabled, the buffer size is used for the initial choice
++ * of the buffer while peeking. It still makes sense to choose an optimal value
++ * to avoid realloc().
++ *
++ * When MSG_PEEK is disabled, the buffer size is important because a too small
++ * size will lead to failure of receiving the message via nl_recvmsgs().
++ *
++ * By default, MSG_PEEK is enabled unless the user calls either nl_socket_disable_msg_peek()/
++ * nl_socket_enable_msg_peek() or sets the message buffer size to a positive value.
++ * See capability NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT for that.
++ *
+ * @return 0 on success or a negative error code.
+ */
+ int nl_socket_set_msg_buf_size(struct nl_sock *sk, size_t bufsize)
+diff --git a/lib/utils.c b/lib/utils.c
+index 0f2a252..d4c0413 100644
+--- a/lib/utils.c
++++ b/lib/utils.c
+@@ -1168,7 +1168,7 @@ int nl_has_capability (int capability)
+ 0,
+ 0,
+ 0,
+- 0),
++ NL_CAPABILITY_NL_RECVMSGS_PEEK_BY_DEFAULT),
+ /* IMPORTANT: these capability numbers are intended to be universal and stable
+ * for libnl3. Don't allocate new numbers on your own that differ from upstream
+ * libnl3.
+--
+2.9.3
+
diff --git a/SPECS/libnl3.spec b/SPECS/libnl3.spec
index ac4fd49..3931bfd 100644
--- a/SPECS/libnl3.spec
+++ b/SPECS/libnl3.spec
@@ -1,6 +1,6 @@
Name: libnl3
Version: 3.2.28
-Release: 2%{?dist}
+Release: 3%{?dist}
Summary: Convenience library for kernel netlink sockets
Group: Development/Libraries
License: LGPLv2
@@ -12,6 +12,7 @@ Source: http://www.infradead.org/~tgr/libnl/files/libnl-%{fullversion}.tar.gz
Source1: http://www.infradead.org/~tgr/libnl/files/libnl-doc-%{fullversion}.tar.gz
Patch1: 0001-compare-v4-addr-rh1370503.patch
+Patch2: 0002-msg-peek-by-default-rh1396882.patch
BuildRequires: flex bison
BuildRequires: python
@@ -52,6 +53,7 @@ This package contains libnl3 API documentation
%prep
%setup -q -n libnl-%{fullversion}
%patch1 -p1
+%patch2 -p1
tar -xzf %SOURCE1
@@ -123,6 +125,9 @@ make check
%doc libnl-doc-%{fullversion}/api/*
%changelog
+* Mon Jan 9 2017 Thomas Haller <thaller@redhat.com> - 3.2.28-3
+- lib: use MSG_PEEK by default for nl_msgrecvs() (rh#1396882)
+
* Fri Aug 26 2016 Thomas Haller <thaller@redhat.com> - 3.2.28-2
- route: fix nl_object_identical() comparing AF_INET addresses (rh #1370503)