Merge 4.4.225 into android-4.4-p

Changes in 4.4.225
	igb: use igb_adapter->io_addr instead of e1000_hw->hw_addr
	padata: Remove unused but set variables
	padata: get_next is never NULL
	padata: ensure the reorder timer callback runs on the correct CPU
	padata: ensure padata_do_serial() runs on the correct CPU
	evm: Check also if *tfm is an error pointer in init_desc()
	fix multiplication overflow in copy_fdtable()
	HID: multitouch: add eGalaxTouch P80H84 support
	ceph: fix double unlock in handle_cap_export()
	USB: core: Fix misleading driver bug report
	platform/x86: asus-nb-wmi: Do not load on Asus T100TA and T200TA
	ARM: futex: Address build warning
	media: Fix media_open() to clear filp->private_data in error leg
	drivers/media/media-devnode: clear private_data before put_device()
	media-devnode: add missing mutex lock in error handler
	media-devnode: fix namespace mess
	media-device: dynamically allocate struct media_devnode
	media: fix use-after-free in cdev_put() when app exits after driver unbind
	media: fix media devnode ioctl/syscall and unregister race
	i2c: dev: switch from register_chrdev to cdev API
	i2c: dev: don't start function name with 'return'
	i2c: dev: use after free in detach
	i2c-dev: don't get i2c adapter via i2c_dev
	i2c: dev: Fix the race between the release of i2c_dev and cdev
	padata: set cpu_index of unused CPUs to -1
	sched/fair, cpumask: Export for_each_cpu_wrap()
	padata: Replace delayed timer with immediate workqueue in padata_reorder
	padata: initialize pd->cpu with effective cpumask
	padata: purge get_cpu and reorder_via_wq from padata_do_serial
	ALSA: pcm: fix incorrect hw_base increase
	ext4: lock the xattr block before checksuming it
	platform/x86: alienware-wmi: fix kfree on potentially uninitialized pointer
	libnvdimm/btt: Remove unnecessary code in btt_freelist_init
	l2tp: lock socket before checking flags in connect()
	l2tp: fix racy socket lookup in l2tp_ip and l2tp_ip6 bind()
	l2tp: hold session while sending creation notifications
	l2tp: take a reference on sessions used in genetlink handlers
	l2tp: don't use l2tp_tunnel_find() in l2tp_ip and l2tp_ip6
	net: l2tp: export debug flags to UAPI
	net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*
	net: l2tp: ppp: change PPPOL2TP_MSG_* => L2TP_MSG_*
	New kernel function to get IP overhead on a socket.
	L2TP:Adjust intf MTU, add underlay L3, L2 hdrs.
	l2tp: remove useless duplicate session detection in l2tp_netlink
	l2tp: remove l2tp_session_find()
	l2tp: define parameters of l2tp_session_get*() as "const"
	l2tp: define parameters of l2tp_tunnel_find*() as "const"
	l2tp: initialise session's refcount before making it reachable
	l2tp: hold tunnel while looking up sessions in l2tp_netlink
	l2tp: hold tunnel while processing genl delete command
	l2tp: hold tunnel while handling genl tunnel updates
	l2tp: hold tunnel while handling genl TUNNEL_GET commands
	l2tp: hold tunnel used while creating sessions with netlink
	l2tp: prevent creation of sessions on terminated tunnels
	l2tp: pass tunnel pointer to ->session_create()
	l2tp: fix l2tp_eth module loading
	l2tp: don't register sessions in l2tp_session_create()
	l2tp: initialise l2tp_eth sessions before registering them
	l2tp: protect sock pointer of struct pppol2tp_session with RCU
	l2tp: initialise PPP sessions before registering them
	Revert "gfs2: Don't demote a glock until its revokes are written"
	staging: iio: ad2s1210: Fix SPI reading
	mei: release me_cl object reference
	iio: sca3000: Remove an erroneous 'get_device()'
	l2tp: device MTU setup, tunnel socket needs a lock
	cpumask: Make for_each_cpu_wrap() available on UP as well
	Linux 4.4.225

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I87dc4ca47f34d594fff7c1da28c7a4596659c029

1 files changed, 46 insertions, 0 deletions

diff --git a/net/socket.c b/net/socket.c
index d700d23858a6..733233ba3144 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -3331,3 +3331,49 @@ int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
 	return sock->ops->shutdown(sock, how);
 }
 EXPORT_SYMBOL(kernel_sock_shutdown);
+
+/* This routine returns the IP overhead imposed by a socket i.e.
+ * the length of the underlying IP header, depending on whether
+ * this is an IPv4 or IPv6 socket and the length from IP options turned
+ * on at the socket. Assumes that the caller has a lock on the socket.
+ */
+u32 kernel_sock_ip_overhead(struct sock *sk)
+{
+	struct inet_sock *inet;
+	struct ip_options_rcu *opt;
+	u32 overhead = 0;
+	bool owned_by_user;
+#if IS_ENABLED(CONFIG_IPV6)
+	struct ipv6_pinfo *np;
+	struct ipv6_txoptions *optv6 = NULL;
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+
+	if (!sk)
+		return overhead;
+
+	owned_by_user = sock_owned_by_user(sk);
+	switch (sk->sk_family) {
+	case AF_INET:
+		inet = inet_sk(sk);
+		overhead += sizeof(struct iphdr);
+		opt = rcu_dereference_protected(inet->inet_opt,
+						owned_by_user);
+		if (opt)
+			overhead += opt->opt.optlen;
+		return overhead;
+#if IS_ENABLED(CONFIG_IPV6)
+	case AF_INET6:
+		np = inet6_sk(sk);
+		overhead += sizeof(struct ipv6hdr);
+		if (np)
+			optv6 = rcu_dereference_protected(np->opt,
+							  owned_by_user);
+		if (optv6)
+			overhead += (optv6->opt_flen + optv6->opt_nflen);
+		return overhead;
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+	default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */
+		return overhead;
+	}
+}
+EXPORT_SYMBOL(kernel_sock_ip_overhead);