Revert "tty: Fix race in tty release"

This reverts commit 1e2d9c24b685f661f625c081bfc8ad93f4b83d88.
Revert "tty: Move the handling of the tty release logic"

This reverts commit 438084d11514b2fa260d97d9f48dc982c0a8d565.
Revert "PTY: add tty_port"

This reverts commit e0e662a64cc6087c2da08f3c91a2e257808e2258.
ipconfig: add nameserver IPs to kernel-parameter ip=

On small systems (e.g. embedded ones) IP addresses are often configured
by bootloaders and get assigned to kernel via parameter "ip=".  If set to
"ip=dhcp", even nameserver entries from DHCP daemons are handled. These
entries exported in /proc/net/pnp are commonly linked by /etc/resolv.conf.

To configure nameservers for networks without DHCP, this patch adds option
<dns0-ip> and <dns1-ip> to kernel-parameter 'ip='.

Signed-off-by: Christoph Fritz <chf.fritz@googlemail.com>
Tested-by: Jan Weitzel <j.weitzel@phytec.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter: ipset: Check and reject crazy /0 input parameters

bitmap:ip and bitmap:ip,mac type did not reject such a crazy range
when created and using such a set results in a kernel crash.
The hash types just silently ignored such parameters.

Reject invalid /0 input parameters explicitely.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
libceph: only kunmap kmapped pages

In write_partial_msg_pages(), pages need to be kmapped in order to
perform a CRC-32c calculation on them.  As an artifact of the way
this code used to be structured, the kunmap() call was separated
from the kmap() call and both were done conditionally.  But the
conditions under which the kmap() and kunmap() calls were made
differed, so there was a chance a kunmap() call would be done on a
page that had not been mapped.

The symptom of this was tripping a BUG() in kunmap_high() when
pkmap_count[nr] became 0.

Reported-by: Bryan K. Wright <bryan@virginia.edu>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
tcp: extract code to compute SYNACK RTT

In preparation for adding another spot where we compute the SYNACK
RTT, extract this code so that it can be shared.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: TCP Fast Open Server - take SYNACK RTT after completing 3WHS

When taking SYNACK RTT samples for servers using TCP Fast Open, fix
the code to ensure that we only call tcp_valid_rtt_meas() after we
receive the ACK that completes the 3-way handshake.

Previously we were always taking an RTT sample in
tcp_v4_syn_recv_sock(). However, for TCP Fast Open connections
tcp_v4_conn_req_fastopen() calls tcp_v4_syn_recv_sock() at the time we
receive the SYN. So for TFO we must wait until tcp_rcv_state_process()
to take the RTT sample.

To fix this, we wait until after TFO calls tcp_v4_syn_recv_sock()
before we set the snt_synack timestamp, since tcp_synack_rtt_meas()
already ensures that we only take a SYNACK RTT sample if snt_synack is
non-zero. To be careful, we only take a snt_synack timestamp when
a SYNACK transmit or retransmit succeeds.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: TCP Fast Open Server - note timestamps and retransmits for SYNACK RTT

Previously, when using TCP Fast Open a server would return from
tcp_check_req() before updating snt_synack based on TCP timestamp echo
replies and whether or not we've retransmitted the SYNACK. The result
was that (a) for TFO connections using timestamps we used an incorrect
baseline SYNACK send time (tcp_time_stamp of SYNACK send instead of
rcv_tsecr), and (b) for TFO connections that do not have TCP
timestamps but retransmit the SYNACK we took a SYNACK RTT sample when
we should not take a sample.

This fix merely moves the snt_synack update logic a bit earlier in the
function, so that connections using TCP Fast Open will properly do
these updates when the ACK for the SYNACK arrives.

Moving this snt_synack update logic means that with TCP_DEFER_ACCEPT
enabled we do a few instructions of wasted work on each bare ACK, but
that seems OK.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp: TCP Fast Open Server - call tcp_validate_incoming() for all packets

A TCP Fast Open (TFO) passive connection must call both
tcp_check_req() and tcp_validate_incoming() for all incoming ACKs that
are attempting to complete the 3WHS.

This is needed to parallel all the action that happens for a non-TFO
connection, where for an ACK that is attempting to complete the 3WHS
we call both tcp_check_req() and tcp_validate_incoming().

For example, upon receiving the ACK that completes the 3WHS, we need
to call tcp_fast_parse_options() and update ts_recent based on the
incoming timestamp value in the ACK.

One symptom of the problem with the previous code was that for passive
TFO connections using TCP timestamps, the outgoing TS ecr values
ignored the incoming TS val value on the ACK that completed the 3WHS.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter: ipset: Support to match elements marked with "nomatch"

Exceptions can now be matched and we can branch according to the
possible cases:

a. match in the set if the element is not flagged as "nomatch"
b. match in the set if the element is flagged with "nomatch"
c. no match

i.e.

iptables ... -m set --match-set ... -j ...
iptables ... -m set --match-set ... --nomatch-entries -j ...
...

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
tcp: TCP Fast Open Server - record retransmits after 3WHS

When recording the number of SYNACK retransmits for servers using TCP
Fast Open, fix the code to ensure that we copy over the retransmit
count from the request_sock after we receive the ACK that completes
the 3-way handshake.

The story here is similar to that of SYNACK RTT
measurements. Previously we were always doing this in
tcp_v4_syn_recv_sock(). However, for TCP Fast Open connections
tcp_v4_conn_req_fastopen() calls tcp_v4_syn_recv_sock() at the time we
receive the SYN. So for TFO we must copy the final SYNACK retransmit
count in tcp_rcv_state_process().

Note that copying over the SYNACK retransmit count will give us the
correct count since, as is mentioned in a comment in
tcp_retransmit_timer(), before we receive an ACK for our SYN-ACK a TFO
passive connection does not retransmit anything else (e.g., data or
FIN segments).

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
batman-adv: Fix change mac address of soft iface.

Into function interface_set_mac_addr, the function tt_local_add was
invoked before updating dev->dev_addr. The new MAC address was not
tagged as NoPurge.

Signed-off-by: Def <def@laposte.net>
batman-adv: Fix symmetry check / route flapping in multi interface setups

If receiving an OGM from a neighbor other than the currently selected
and if it has the same TQ then we are supposed to switch if this
neighbor provides a more symmetric link than the currently selected one.

However this symmetry check currently is broken if the interface of the
neighbor we received the OGM from and the one of the currently selected
neighbor differ: We are currently trying to determine the symmetry of the
link towards the selected router via the link we received the OGM from
instead of just checking via the link towards the currently selected
router.

This leads to way more route switches than necessary and can lead to
permanent route flapping in many common multi interface setups.

This patch fixes this issue by using the right interface for this
symmetry check.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
rfkill: prevent unnecessary event generation

Prevent unnecessary rfkill event generation when the state has
not actually changed. These events have to be delivered to
relevant userspace processes, causing these processes to wake
up and do something while they could as well have slept. This
obviously results in more CPU usage, longer time-to-sleep-again
and therefore higher power consumption.

Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Mykyta Iziumtsev <nikita.izyumtsev@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
netfilter: xt_time: add support to ignore day transition

Currently, if you want to do something like:
"match Monday, starting 23:00, for two hours"
You need two rules, one for Mon 23:00 to 0:00 and one for Tue 0:00-1:00.

The rule: --weekdays Mo --timestart 23:00  --timestop 01:00

looks correct, but it will first match on monday from midnight to 1 a.m.
and then again for another hour from 23:00 onwards.

This permits userspace to explicitly ignore the day transition and
match for a single, continuous time period instead.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nf_ct_ftp: add sequence tracking pickup facility for injected entries

This patch allows the FTP helper to pickup the sequence tracking from
the first packet seen. This is useful to fix the breakage of the first
FTP command after the failover while using conntrackd to synchronize
states.

The seq_aft_nl_num field in struct nf_ct_ftp_info has been shrinked to
16-bits (enough for what it does), so we can use the remaining 16-bits
to store the flags while using the same size for the private FTP helper
data.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nfnetlink_queue: fix maximum packet length to userspace

The packets that we send via NFQUEUE are encapsulated in the NFQA_PAYLOAD
attribute. The length of the packet in userspace is obtained via
attr->nla_len field. This field contains the size of the Netlink
attribute header plus the packet length.

If the maximum packet length is specified, ie. 65535 bytes, and
packets in the range of (65531,65535] are sent to userspace, the
attr->nla_len overflows and it reports bogus lengths to the
application.

To fix this, this patch limits the maximum packet length to 65531
bytes. If larger packet length is specified, the packet that we
send to user-space is truncated to 65531 bytes.

To support 65535 bytes packets, we have to revisit the idea of
the 32-bits Netlink attribute length.

Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nfnetlink_queue: add NFQA_CAP_LEN attribute

This patch adds the NFQA_CAP_LEN attribute that allows us to know
what is the real packet size from user-space (even if we decided
to retrieve just a few bytes from the packet instead of all of it).

Security software that inspects packets should always check for
this new attribute to make sure that it is inspecting the entire
packet.

This also helps to provide a workaround for the problem described
in: http://marc.info/?l=netfilter-devel&m=134519473212536&w=2

Original idea from Florian Westphal.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/sock.h: fix sk_peek_off kernel-doc warning

Fix kernel-doc warning in net/sock.h:

Warning(include/net/sock.h:377): No description found for parameter 'sk_peek_off'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>