This change introduces a new sysctl parameter, arp_evict_nocarrier.
When set (default) the ARP cache will be cleared on a NOCARRIER event.
This new option has been defaulted to '1' which maintains existing
behavior.

Clearing the ARP cache on NOCARRIER is relatively new, introduced by:

commit 859bd2ef
Author: David Ahern <dsahern@gmail.com>
Date:   Thu Oct 11 20:33:49 2018 -0700

    net: Evict neighbor entries on carrier down

The reason for this changes is to prevent the ARP cache from being
cleared when a wireless device roams. Specifically for wireless roams
the ARP cache should not be cleared because the underlying network has not
changed. Clearing the ARP cache in this case can introduce significant
delays sending out packets after a roam.

A user reported such a situation here:

https://lore.kernel.org/linux-wireless/CACsRnHWa47zpx3D1oDq9JYnZWniS8yBwW1h0WAVZ6vrbwL_S0w@mail.gmail.com/

After some investigation it was found that the kernel was holding onto
packets until ARP finished which resulted in this 1 second delay. It
was also found that the first ARP who-has was never responded to,
which is actually what caues the delay. This change is more or less
working around this behavior, but again, there is no reason to clear
the cache on a roam anyways.

As for the unanswered who-has, we know the packet made it OTA since
it was seen while monitoring. Why it never received a response is
unknown. In any case, since this is a problem on the AP side of things
all that can be done is to work around it until it is solved.

Some background on testing/reproducing the packet delay:

Hardware:
 - 2 access points configured for Fast BSS Transition (Though I don't
   see why regular reassociation wouldn't have the same behavior)
 - Wireless station running IWD as supplicant
 - A device on network able to respond to pings (I used one of the APs)

Procedure:
 - Connect to first AP
 - Ping once to establish an ARP entry
 - Start a tcpdump
 - Roam to second AP
 - Wait for operstate UP event, and note the timestamp
 - Start pinging

Results:

Below is the tcpdump after UP. It was recorded the interface went UP at
10:42:01.432875.

10:42:01.461871 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.497976 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.507162 ARP, Reply 192.168.254.1 is-at ac:86:74:55:b0:20, length 46
10:42:02.507185 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 1, length 64
10:42:02.507205 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 2, length 64
10:42:02.507212 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 3, length 64
10:42:02.507219 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 4, length 64
10:42:02.507225 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 5, length 64
10:42:02.507232 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 6, length 64
10:42:02.515373 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 1, length 64
10:42:02.521399 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 2, length 64
10:42:02.521612 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 3, length 64
10:42:02.521941 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 4, length 64
10:42:02.522419 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 5, length 64
10:42:02.523085 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 6, length 64

You can see the first ARP who-has went out very quickly after UP, but
was never responded to. Nearly a second later the kernel retries and
gets a response. Only then do the ping packets go out. If an ARP entry
is manually added prior to UP (after the cache is cleared) it is seen
that the first ping is never responded to, so its not only an issue with
ARP but with data packets in general.

As mentioned prior, the wireless interface was also monitored to verify
the ping/ARP packet made it OTA which was observed to be true.
Signed-off-by: NJames Prestwood <prestwoj@gmail.com>
Reviewed-by: NDavid Ahern <dsahern@kernel.org>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Track skbs with only zerocopy data and avoid charging them to kernel
memory to correctly account the memory utilization for msg_zerocopy.
All of the data in such skbs is held in user pages which are already
accounted to user. Before this change, they are charged again in
kernel in __zerocopy_sg_from_iter. The charging in kernel is
excessive because data is not being copied into skb frags. This
excessive charging can lead to kernel going into memory pressure
state which impacts all sockets in the system adversely. Mark pure
zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove
charge/uncharge for data in such skbs.

Initially, an skb is marked pure zerocopy when it is empty and in
zerocopy path. skb can then change from a pure zerocopy skb to mixed
data skb (zerocopy and copy data) if it is at tail of write queue and
there is room available in it and non-zerocopy data is being sent in
the next sendmsg call. At this time sk_mem_charge is done for the pure
zerocopied data and the pure zerocopy flag is unmarked. We found that
this happens very rarely on workloads that pass MSG_ZEROCOPY.

A pure zerocopy skb can later be coalesced into normal skb if they are
next to each other in queue but this patch prevents coalescing from
happening. This avoids complexity of charging when skb downgrades from
pure zerocopy to mixed. This is also rare.

In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge
for SKB_TRUESIZE(MAX_TCP_HEADER) is done for sk_mem_charge in
tcp_skb_entail for an skb without data.

Testing with the msg_zerocopy.c benchmark between two hosts(100G nics)
with zerocopy showed that before this patch the 'sock' variable in
memory.stat for cgroup2 that tracks sum of sk_forward_alloc,
sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this
change it is 0. This is due to no charge to sk_forward_alloc for
zerocopy data and shows memory utilization for kernel is lowered.
Signed-off-by: NTalal Ahmad <talalahmad@google.com>
Acked-by: NArjun Roy <arjunroy@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

sk_wmem_free_skb() is only used by TCP.

Rename it to make this clear, and move its declaration to
include/net/tcp.h
Signed-off-by: NTalal Ahmad <talalahmad@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NArjun Roy <arjunroy@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

SMC-R link down event is important to help us find links' issues, we
should track this event, especially in the single nic mode, which means
upper layer connection would be shut down. Then find out the direct
link-down reason in time, not only increased the counter, also the
location of the code who triggered this event.
Signed-off-by: NTony Lu <tonylu@linux.alibaba.com>
Reviewed-by: NWen Gu <guwen@linux.alibaba.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This introduce two tracepoints for smc tx and rx msg to help us
diagnosis issues of data path. These two tracepoitns don't cover the
path of CORK or MSG_MORE in tx, just the top half of data path.
Signed-off-by: NTony Lu <tonylu@linux.alibaba.com>
Reviewed-by: NWen Gu <guwen@linux.alibaba.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This introduces tracepoint for smc fallback to TCP, so that we can track
which connection and why it fallbacks, and map the clcsocks' pointer with
/proc/net/tcp to find more details about TCP connections. Compared with
kprobe or other dynamic tracing, tracepoints are stable and easy to use.
Signed-off-by: NTony Lu <tonylu@linux.alibaba.com>
Reviewed-by: NWen Gu <guwen@linux.alibaba.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

devlink compat code needs to drop rtnl_lock to take
devlink->lock to ensure correct lock ordering.

This is problematic because we're not strictly guaranteed
that the netdev will not disappear after we re-lock.
It may open a possibility of nested ->begin / ->complete
calls.

Instead of calling into devlink under rtnl_lock take
a ref on the devlink instance and make the call after
we've dropped rtnl_lock.

We (continue to) assume that netdevs have an implicit
reference on the devlink returned from ndo_get_devlink_port

Note that ndo_get_devlink_port will now get called
under rtnl_lock. That should be fine since none of
the drivers seem to be taking serious locks inside
ndo_get_devlink_port.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow those who hold implicit reference on a devlink instance
to try to take a full ref on it. This will be used from netdev
code which has an implicit ref because of driver call ordering.

Note that after recent changes devlink_unregister() may happen
before netdev unregister, but devlink_free() should still happen
after, so we are safe to try, but we can't just refcount_inc()
and assume it's not zero.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to increase the lifetime of the data for .get_info
and .flash_update beyond their handlers inside rtnl_lock.

Allocate a union on the heap and use it instead.

Note that we now copy the ethcmd before we lookup dev,
hopefully there is no crazy user space depending on error
codes.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't take the lock in net/core/dev_ioctl.c,
we'll have things to do outside rtnl_lock soon.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a new DSA switch operation, phylink_get_interfaces, which should
fill in which PHY_INTERFACE_MODE_* are supported by given port.

Use this before phylink_create() to fill phylinks supported_interfaces
member, allowing phylink to determine which PHY_INTERFACE_MODEs are
supported.
Signed-off-by: NMarek Behún <kabel@kernel.org>
[tweaked patch and description to add more complete support -- rmk]
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow to match and mangle on inner headers / payload data after the
transport header. There is a new field in the pktinfo structure that
stores the inner header offset which is calculated only when requested.
Only TCP and UDP supported at this stage.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Generalize boolean field to store more flags on the pktinfo structure.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Generalize NFT_META_IIFTYPE to NFT_META_IFTYPE which allows you to match
on the interface type of the skb->dev field. This field is used by the
netdev family to add an implicit dependency to skip non-ethernet packets
when matching on layer 3 and 4 TCP/IP header fields.

For backward compatibility, add the NFT_META_IIFTYPE alias to
NFT_META_IFTYPE.

Add __NFT_META_IIFTYPE, to be used by userspace in the future to match
specifically on the iiftype.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

The internal stream state sets the timeout to 120 seconds 2 seconds
after the creation of the flow, attach this internal stream state to the
IPS_ASSURED flag for consistent event reporting.

Before this patch:

      [NEW] udp      17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 [UNREPLIED] src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282
   [UPDATE] udp      17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282
   [UPDATE] udp      17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED]
  [DESTROY] udp      17 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED]

Note IPS_ASSURED for the flow not yet in the internal stream state.

after this update:

      [NEW] udp      17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 [UNREPLIED] src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282
   [UPDATE] udp      17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282
   [UPDATE] udp      17 120 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED]
  [DESTROY] udp      17 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED]

Before this patch, short-lived UDP flows never entered IPS_ASSURED, so
they were already candidate flow to be deleted by early_drop under
stress.

Before this patch, IPS_ASSURED is set on regardless the internal stream
state, attach this internal stream state to IPS_ASSURED.

packet #1 (original direction) enters NEW state
packet #2 (reply direction) enters ESTABLISHED state, sets on IPS_SEEN_REPLY
paclet #3 (any direction) sets on IPS_ASSURED (if 2 seconds since the
          creation has passed by).
Reported-by: NMaciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

br_switchdev_mdb_notify() is conditionally compiled only when
CONFIG_NET_SWITCHDEV=y and CONFIG_BRIDGE_IGMP_SNOOPING=y. It is called
from br_mdb.c, which is conditionally compiled only when
CONFIG_BRIDGE_IGMP_SNOOPING=y.

The shim definition of br_switchdev_mdb_notify() is therefore needed for
the case where CONFIG_NET_SWITCHDEV=n, however we mistakenly put it
there for the case where CONFIG_BRIDGE_IGMP_SNOOPING=n. This results in
build failures when CONFIG_BRIDGE_IGMP_SNOOPING=y and
CONFIG_NET_SWITCHDEV=n.

To fix this, put the shim definition right next to
br_switchdev_fdb_notify(), which is properly guarded by NET_SWITCHDEV=n.
Since this is called only from br_mdb.c, we need not take any extra
safety precautions, when NET_SWITCHDEV=n and BRIDGE_IGMP_SNOOPING=n,
this shim definition will be absent but nobody will be needing it.

Fixes: 9776457c ("net: bridge: mdb: move all switchdev logic to br_switchdev.c")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20211029223606.3450523-1-vladimir.oltean@nxp.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

devlink_alloc() and devlink_register() are both GPL.
A non-GPL module won't get far, so for consistency
we can make all symbols GPL without risking any real
life breakage.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we have an extension for MCTP data in skbs, populate the flow
when a key has been created for the packet, and add a device driver
operation to inform of flow destruction.

Includes a fix for a warning with test builds:
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NJeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change adds a new skb extension for MCTP, to represent a
request/response flow.

The intention is to use this in a later change to allow i2c controllers
to correctly configure a multiplexer over a flow.

Since we have a cleanup function in the core path (if an extension is
present), we'll need to make CONFIG_MCTP a bool, rather than a tristate.

Includes a fix for a build warning with clang:
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NJeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In a future change, we will want the key available for future use after
allocating a new tag. This change returns the key from
mctp_alloc_local_tag, rather than just key->tag.
Signed-off-by: NJeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename all recently imported functions in br_switchdev.c to start with a
br_switchdev_* prefix.

br_fdb_replay_one() -> br_switchdev_fdb_replay_one()
br_fdb_replay() -> br_switchdev_fdb_replay()
br_vlan_replay_one() -> br_switchdev_vlan_replay_one()
br_vlan_replay() -> br_switchdev_vlan_replay()
struct br_mdb_complete_info -> struct br_switchdev_mdb_complete_info
br_mdb_complete() -> br_switchdev_mdb_complete()
br_mdb_switchdev_host_port() -> br_switchdev_host_mdb_one()
br_mdb_switchdev_host() -> br_switchdev_host_mdb()
br_mdb_replay_one() -> br_switchdev_mdb_replay_one()
br_mdb_replay() -> br_switchdev_mdb_replay()
br_mdb_queue_one() -> br_switchdev_mdb_queue_one()
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

The following functions:

br_mdb_complete
br_switchdev_mdb_populate
br_mdb_replay_one
br_mdb_queue_one
br_mdb_replay
br_mdb_switchdev_host_port
br_mdb_switchdev_host
br_switchdev_mdb_notify

are only accessible from code paths where CONFIG_NET_SWITCHDEV is
enabled. So move them to br_switchdev.c, in order for that code to be
compiled out if that config option is disabled.

Note that br_switchdev.c gets build regardless of whether
CONFIG_BRIDGE_IGMP_SNOOPING is enabled or not, whereas br_mdb.c only got
built when CONFIG_BRIDGE_IGMP_SNOOPING was enabled. So to preserve
correct compilation with CONFIG_BRIDGE_IGMP_SNOOPING being disabled, we
must now place an #ifdef around these functions in br_switchdev.c.
The offending bridge data structures that need this are
br->multicast_lock and br->mdb_list, these are also compiled out of
struct net_bridge when CONFIG_BRIDGE_IGMP_SNOOPING is turned off.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Similar to fdb_notify() and br_switchdev_fdb_notify(), split the
switchdev specific logic from br_mdb_notify() into a different function.
This will be moved later in br_switchdev.c.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

br_vlan_replay() is relevant only if CONFIG_NET_SWITCHDEV is enabled, so
move it to br_switchdev.c.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

br_vlan_replay() needs this, and we're preparing to move it to
br_switchdev.c, which will be compiled regardless of whether or not
CONFIG_BRIDGE_VLAN_FILTERING is enabled.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

using packetdrill it's possible to observe that the receiver key contains
random values when clients transmit MP_CAPABLE with data and checksum (as
specified in RFC8684 §3.1). Fix the layout of mptcp_out_options, to avoid
using the skb extension copy when writing the MP_CAPABLE sub-option.

Fixes: d7b26908 ("mptcp: shrink mptcp_out_options struct")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/233Reported-by: NPoorva Sonparote <psonparo@redhat.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20211027203855.264600-1-mathew.j.martineau@linux.intel.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

Reduce extra indirection from devlink_params_*() API. Such change
makes it clear that we can drop devlink->lock from these flows, because
everything is executed when the devlink is not registered yet.
Signed-off-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_err contains a positive number, yet async_wait.err wants the
opposite.  Fix the missed sign flip, which Jakub caught by inspection.

Fixes: a42055e8 ("net/tls: Add support for async encryption of records for performance")
Suggested-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_err appears to expect a positive value, a convention that ktls
doesn't always follow and that leads to memory corruption in other code.
For instance,

    [kworker]
    tls_encrypt_done(..., err=<negative error from crypto request>)
      tls_err_abort(.., err)
        sk->sk_err = err;

    [task]
    splice_from_pipe_feed
      ...
        tls_sw_do_sendpage
          if (sk->sk_err) {
            ret = -sk->sk_err;  // ret is positive

    splice_from_pipe_feed (continued)
      ret = actor(...)  // ret is still positive and interpreted as bytes
                        // written, resulting in underflow of buf->len and
                        // sd->len, leading to huge buf->offset and bogus
                        // addresses computed in later calls to actor()

Fix all tls_err_abort() callers to pass a negative error code
consistently and centralize the error-prone sign flip there, throwing in
a warning to catch future misuse and uninlining the function so it
really does only warn once.

Cc: stable@vger.kernel.org
Fixes: c46234eb ("tls: RX path for ktls")
Reported-by: syzbot+b187b77c8474f9648fae@syzkaller.appspotmail.com
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While waiting for a carrier to come on one of the netdevices, some
devices will require to take the rtnl lock at some point to fully
initialize all parts of the link.

That's the case for SFP, where the rtnl is taken when a module gets
detected. This prevents mounting an NFS rootfs over an SFP link.

This means that while ipconfig waits for carriers to be detected, no SFP
modules can be detected in the meantime, it's only detected after
ipconfig times out.

This commit releases the rtnl_lock while waiting for the carrier to come
up, and re-takes it to check the for the init device and carrier status.
Signed-off-by: NMaxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to make the "Operation not supported" message clearer to the
user, add extack messages explaining why exactly adding offloaded HTB
could be not supported in each case.
Signed-off-by: NMaxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: NTariq Toukan <tariqt@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There should use TCPF_SYN_RECV instead of TCP_SYN_RECV.
Signed-off-by: NWen Gu <guwen@linux.alibaba.com>
Reviewed-by: NTony Lu <tonylu@linux.alibaba.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The value of llc_testlink_time is set to the value stored in
net->ipv4.sysctl_tcp_keepalive_time when linkgroup init. The value of
sysctl_tcp_keepalive_time is already jiffies, so we don't need to
multiply by HZ, which would cause smc_link->llc_testlink_time overflow,
and test_link send flood.
Signed-off-by: NTony Lu <tonylu@linux.alibaba.com>
Reviewed-by: NXuan Zhuo <xuanzhuo@linux.alibaba.com>
Reviewed-by: NWen Gu <guwen@linux.alibaba.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We want to increase route cache size in network namespace
created with user namespace. Currently ipv6 route settings
are disabled for non-initial network namespaces.
We can allow this sysctl and it will be safe since
commit <6126891c> because route cache account to kmem,
that is why users from user namespace can not DOS system.
Signed-off-by: NAlexander Kuznetsov <wwfq@yandex-team.ru>
Acked-by: NDmitry Yakunin <zeil@yandex-team.ru>
Acked-by: NDmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Freshly allocated skbs have zero in skb->cb[] already.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Freshly allocated skbs have their csum field cleared already.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized
in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb()
instead of being done multiple times.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TCP/MPTCP sendmsg() no longer puts payload in skb->head,
we can remove not needed code.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TCP sendmsg() no longer puts payload in skb->head,
remove some dead code from tcp_collapse_retrans().
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All tcp_remove_empty_skb() callers now use tcp_write_queue_tail()
for the skb argument, we can therefore factorize code.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>