t_name cannot be NULL since it is an array field of a struct.
Replacing null check on static array with string length check using
strnlen()
Signed-off-by: NPrashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TC actions are no longer freed in RCU callbacks and we should
always have RTNL lock, so this spinlock is no longer needed.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcfm_dev always points to the correct netdev and we already
hold a refcnt, so no need to use tcfm_ifindex to lookup again.

If we would support moving target netdev across netns, using
pointer would be better than ifindex.

This also fixes dumping obsolete ifindex, now after the
target device is gone we just dump 0 as ifindex.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to ip6 gretap and ip4 gretap, the patch allows
erspan tunnel to operate in collect metadata mode.
bpf_skb_[gs]et_tunnel_key() helpers can make use of
it right away.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No one actually uses it.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DSA ports also need to have a dedicated CPU port assigned to them,
because they need to know where to egress frames targeting the CPU,
e.g. To_Cpu frames received on a Marvell Tag port.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the following checkpatch error:

ERROR: do not use assignment in if condition

by rearranging the if condition to execute init callback only if init
callback exists. The whole setup afterwards is called in any case,
doesn't matter if init callback is set or not. This patch has the same
behaviour as before, just without assign err variable in if condition.
It also makes the code easier to read.
Reviewed-by: NJamal Hadi Salim <jhs@mojatatu.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fix checkpatch issues for upcomming patches according to the
sched api file. It changes checking on null pointer, remove unnecessary
brackets, add variable names for parameters and adjust 80 char width.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both Eric and Paolo noticed the rcu_barrier() we use in
tcf_block_put_ext() could be a performance bottleneck when
we have a lot of tc classes.

Paolo provided the following to demonstrate the issue:

tc qdisc add dev lo root htb
for I in `seq 1 1000`; do
        tc class add dev lo parent 1: classid 1:$I htb rate 100kbit
        tc qdisc add dev lo parent 1:$I handle $((I + 1)): htb
        for J in `seq 1 10`; do
                tc filter add dev lo parent $((I + 1)): u32 match ip src 1.1.1.$J
        done
done
time tc qdisc del dev root

real    0m54.764s
user    0m0.023s
sys     0m0.000s

The rcu_barrier() there is to ensure we free the block after all chains
are gone, that is, to queue tcf_block_put_final() at the tail of workqueue.
We can achieve this ordering requirement by refcnt'ing tcf block instead,
that is, the tcf block is freed only when the last chain in this block is
gone. This also simplifies the code.

Paolo reported after this patch we get:

real    0m0.017s
user    0m0.000s
sys     0m0.017s
Tested-by: NPaolo Abeni <pabeni@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move dissection of tunnel info to outside of the main flow dissection
function, __skb_flow_dissect(). The sole user of this feature, the flower
classifier, is updated to call tunnel info dissection directly, using
skb_flow_dissect_tunnel_info().

This results in a slightly less complex implementation of
__skb_flow_dissect(), in particular removing logic from that call path
which is not used by the majority of users. The expense of this is borne by
the flower classifier which now has to make an extra call for tunnel info
dissection.

This patch should not result in any behavioural change.
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Incorrect/missing annotations caused a few sparse warnings:

rtnetlink.c:155:15: incompatible types .. (different address spaces)
rtnetlink.c:157:23: incompatible types .. (different address spaces)
rtnetlink.c:185:15: incompatible types .. (different address spaces)
rtnetlink.c:285:15: incompatible types .. (different address spaces)
rtnetlink.c:317:9: incompatible types .. (different address spaces)
rtnetlink.c:3054:23: incompatible types .. (different address spaces)

no change in generated code.

Fixes: addf9b90 ("net: rtnetlink: use rcu to free rtnl message handlers")
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

convert remaining users of rtnl_register to rtnl_register_module
and un-export rtnl_register.
Requested-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This removes __rtnl_register and switches callers to either
rtnl_register or rtnl_register_module.

Also, rtnl_register() will now print an error if memory allocation
failed rather than panic the kernel.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

all of these can be compiled as a module, so use new
_module version to make sure module can no longer be removed
while callback/dump is in use.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add yet another rtnl_register function.  It will be used by modules
that can be removed.

The passed module struct is used to prevent module unload while
a netlink dump is in progress or when a DOIT_UNLOCKED doit callback
is called.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnetlink is littered with READ_ONCE() because we can have read accesses
while another cpu can write to the structure we're reading by
(un)registering doit or dumpit handlers.

This patch changes this so that (un)registering cpu allocates a new
structure and then publishes it via rcu_assign_pointer, i.e. once
another cpu can see such pointer no modifications will occur anymore.

based on initial patch from Peter Zijlstra.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before the patch, BPF_F_ZERO_CSUM_TX can be used only for ipv4 tunnel.
With introduction of ip6gretap collect_md mode, the flag should be also
supported for ipv6.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to gre, vxlan, geneve, ipip tunnels, allow ip6 gre and gretap
tunnels to operate in collect metadata mode.  bpf_skb_[gs]et_tunnel_key()
helpers can make use of it right away.  OVS can use it as well in the
future.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

James Morris reported kernel stack corruption bug [1] while
running the SELinux testsuite, and bisected to a recent
commit bffa72cf ("net: sk_buff rbnode reorg")

We believe this commit is fine, but exposes an older bug.

SELinux code runs from tcp_filter() and might send an ICMP,
expecting IP options to be found in skb->cb[] using regular IPCB placement.

We need to defer TCP mangling of skb->cb[] after tcp_filter() calls.

This patch adds tcp_v4_fill_cb()/tcp_v4_restore_cb() in a very
similar way we added them for IPv6.

[1]
[  339.806024] SELinux: failure in selinux_parse_skb(), unable to parse packet
[  339.822505] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff81745af5
[  339.822505]
[  339.852250] CPU: 4 PID: 3642 Comm: client Not tainted 4.15.0-rc1-test #15
[  339.868498] Hardware name: LENOVO 10FGS0VA1L/30BC, BIOS FWKT68A   01/19/2017
[  339.885060] Call Trace:
[  339.896875]  <IRQ>
[  339.908103]  dump_stack+0x63/0x87
[  339.920645]  panic+0xe8/0x248
[  339.932668]  ? ip_push_pending_frames+0x33/0x40
[  339.946328]  ? icmp_send+0x525/0x530
[  339.958861]  ? kfree_skbmem+0x60/0x70
[  339.971431]  __stack_chk_fail+0x1b/0x20
[  339.984049]  icmp_send+0x525/0x530
[  339.996205]  ? netlbl_skbuff_err+0x36/0x40
[  340.008997]  ? selinux_netlbl_err+0x11/0x20
[  340.021816]  ? selinux_socket_sock_rcv_skb+0x211/0x230
[  340.035529]  ? security_sock_rcv_skb+0x3b/0x50
[  340.048471]  ? sk_filter_trim_cap+0x44/0x1c0
[  340.061246]  ? tcp_v4_inbound_md5_hash+0x69/0x1b0
[  340.074562]  ? tcp_filter+0x2c/0x40
[  340.086400]  ? tcp_v4_rcv+0x820/0xa20
[  340.098329]  ? ip_local_deliver_finish+0x71/0x1a0
[  340.111279]  ? ip_local_deliver+0x6f/0xe0
[  340.123535]  ? ip_rcv_finish+0x3a0/0x3a0
[  340.135523]  ? ip_rcv_finish+0xdb/0x3a0
[  340.147442]  ? ip_rcv+0x27c/0x3c0
[  340.158668]  ? inet_del_offload+0x40/0x40
[  340.170580]  ? __netif_receive_skb_core+0x4ac/0x900
[  340.183285]  ? rcu_accelerate_cbs+0x5b/0x80
[  340.195282]  ? __netif_receive_skb+0x18/0x60
[  340.207288]  ? process_backlog+0x95/0x140
[  340.218948]  ? net_rx_action+0x26c/0x3b0
[  340.230416]  ? __do_softirq+0xc9/0x26a
[  340.241625]  ? do_softirq_own_stack+0x2a/0x40
[  340.253368]  </IRQ>
[  340.262673]  ? do_softirq+0x50/0x60
[  340.273450]  ? __local_bh_enable_ip+0x57/0x60
[  340.285045]  ? ip_finish_output2+0x175/0x350
[  340.296403]  ? ip_finish_output+0x127/0x1d0
[  340.307665]  ? nf_hook_slow+0x3c/0xb0
[  340.318230]  ? ip_output+0x72/0xe0
[  340.328524]  ? ip_fragment.constprop.54+0x80/0x80
[  340.340070]  ? ip_local_out+0x35/0x40
[  340.350497]  ? ip_queue_xmit+0x15c/0x3f0
[  340.361060]  ? __kmalloc_reserve.isra.40+0x31/0x90
[  340.372484]  ? __skb_clone+0x2e/0x130
[  340.382633]  ? tcp_transmit_skb+0x558/0xa10
[  340.393262]  ? tcp_connect+0x938/0xad0
[  340.403370]  ? ktime_get_with_offset+0x4c/0xb0
[  340.414206]  ? tcp_v4_connect+0x457/0x4e0
[  340.424471]  ? __inet_stream_connect+0xb3/0x300
[  340.435195]  ? inet_stream_connect+0x3b/0x60
[  340.445607]  ? SYSC_connect+0xd9/0x110
[  340.455455]  ? __audit_syscall_entry+0xaf/0x100
[  340.466112]  ? syscall_trace_enter+0x1d0/0x2b0
[  340.476636]  ? __audit_syscall_exit+0x209/0x290
[  340.487151]  ? SyS_connect+0xe/0x10
[  340.496453]  ? do_syscall_64+0x67/0x1b0
[  340.506078]  ? entry_SYSCALL64_slow_path+0x25/0x25

Fixes: 971f10ec ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NJames Morris <james.l.morris@oracle.com>
Tested-by: NJames Morris <james.l.morris@oracle.com>
Tested-by: NCasey Schaufler <casey@schaufler-ca.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable the second listener hashtable in TCP.
The scale is the same as UDP which is one slot per 2MB.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current listener hashtable is hashed by port only.
When a process is listening at many IP addresses with the same port (e.g.
[IP1]:443, [IP2]:443... [IPN]:443), the inet[6]_lookup_listener()
performance is degraded to a link list.  It is prone to syn attack.

UDP had a similar issue and a second hashtable was added to resolve it.

This patch adds a second hashtable for the listener's sockets.
The second hashtable is hashed by port and address.

It cannot reuse the existing skc_portaddr_node which is shared
with skc_bind_node.  TCP listener needs to use skc_bind_node.
Instead, this patch adds a hlist_node 'icsk_listen_portaddr_node' to
the inet_connection_sock which the listener (like TCP) also belongs to.

The new portaddr hashtable may need two lookup (First by IP:PORT.
Second by INADDR_ANY:PORT if the IP:PORT is a not found).   Hence,
it implements a similar cut off as UDP such that it will only consult the
new portaddr hashtable if the current port-only hashtable has >10
sk in the link-list.

lhash2 and lhash2_mask are added to 'struct inet_hashinfo'.  I take
this chance to plug a 4 bytes hole.  It is done by first moving
the existing bind_bucket_cachep up and then add the new
(int lhash2_mask, *lhash2) after the existing bhash_size.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch moves the udp[46]_portaddr_hash()
to net/ip[v6].h.  The function name is renamed to
ipv[46]_portaddr_hash().

It will be used by a later patch which adds a second listener
hashtable hashed by the address and port.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a count to the 'struct inet_listen_hashbucket'.
It counts how many sk is hashed to a bucket.  It will be
used to decide if the (to-be-added) portaddr listener's hashtable
should be used during inet[6]_lookup_listener().
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In rxrpc_release_sock() there may be no rx->local value to access, so we
can't unconditionally follow it to the rxrpc network namespace information
to poke the connection reapers.

Instead, use the socket's namespace pointer to find the namespace.

This unfixed code causes the following static checker warning:

	net/rxrpc/af_rxrpc.c:898 rxrpc_release_sock()
	error: we previously assumed 'rx->local' could be null (see line 887)

Fixes: 3d18cbb7 ("rxrpc: Fix conn expiry timers")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a MAC address is added to or removed from a switch port in the
fabric, the target switch must program its port and adjacent switches
must program their local DSA port used to reach the target switch.

For this purpose, use the dsa_towards_port() helper to identify the
local switch port which must be programmed.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch brings no functional changes.
It moves out the MDB code iterating on a multicast group into new
dsa_switch_mdb_{prepare,add}_bitmap() functions.

This gives us a better isolation of the two switchdev phases.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch brings no functional changes.
It moves out the VLAN code iterating on a list of VLAN members into new
dsa_switch_vlan_{prepare,add}_bitmap() functions.

This gives us a better isolation of the two switchdev phases.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The DSA switch MDB ops pass the switchdev_trans structure down to the
drivers, but no one is using them and they aren't supposed to anyway.

Remove the trans argument from MDB prepare and add operations.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The DSA switch VLAN ops pass the switchdev_trans structure down to the
drivers, but no one is using them and they aren't supposed to anyway.

Remove the trans argument from VLAN prepare and add operations.

At the same time, fix the following checkpatch warning:

    WARNING: line over 80 characters
    #74: FILE: drivers/net/dsa/dsa_loop.c:177:
    +				      const struct switchdev_obj_port_vlan *vlan)
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After commit 3a927bc7 ("ovs: propagate per dp max headroom to
all vports") the need_headroom for the internal vport is updated
accordingly to the max needed headroom in its datapath.

That avoids the pskb_expand_head() costs when sending/forwarding
packets towards tunnel devices, at least for some scenarios.

We still require such copy when using the ovs-preferred configuration
for vxlan tunnels:

    br_int
  /       \
tap      vxlan
           (remote_ip:X)

br_phy
     \
    NIC

where the route towards the IP 'X' is via 'br_phy'.

When forwarding traffic from the tap towards the vxlan device, we
will call pskb_expand_head() in vxlan_build_skb() because
br-phy->needed_headroom is equal to tun->needed_headroom.

With this change we avoid updating the internal vport needed_headroom,
so that in the above scenario no head copy is needed, giving 5%
performance improvement in UDP throughput test.

As a trade-off, packets sent from the internal port towards a tunnel
device will now experience the head copy overhead. The rationale is
that the latter use-case is less relevant performance-wise.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NPravin B Shelar <pshelar@ovn.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since day one of XDP drivers had to remember to free the program
on the remove path.  This leads to code duplication and is error
prone.  Make the stack query the installed programs on unregister
and if something is installed, remove the program.  Freeing of
program attached to XDP generic is moved from free_netdev() as well.

Because the remove will now be called before notifiers are
invoked, BPF offload state of the program will not get destroyed
before uninstall.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The output parameters will get unwieldy if we want to add more
information about the program.  Simply pass the entire
struct netdev_bpf in.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The patch adds support for ERSPAN tunnel over ipv6.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch refactors the ip6gre_xmit_{ipv4, ipv6}.
It is a prep work to add the ip6erspan tunnel.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move two erspan functions to header file, erspan.h, so ipv6
erspan implementation can use it.
Signed-off-by: NWilliam Tu <u9012063@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rds_tcp_kill_sock() function parses the rds_tcp_conn_list
to find the rds_connection entries marked for deletion as part
of the netns deletion under the protection of the rds_tcp_conn_lock.
Since the rds_tcp_conn_list tracks rds_tcp_connections (which
have a 1:1 mapping with rds_conn_path), multiple tc entries in
the rds_tcp_conn_list will map to a single rds_connection, and will
be deleted as part of the rds_conn_destroy() operation that is
done outside the rds_tcp_conn_lock.

The rds_tcp_conn_list traversal done under the protection of
rds_tcp_conn_lock should not leave any doomed tc entries in
the list after the rds_tcp_conn_lock is released, else another
concurrently executiong netns delete (for a differnt netns) thread
may trip on these entries.
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 8edc3aff ("rds: tcp: Take explicit refcounts on struct net")
introduces a regression in rds-tcp netns cleanup. The cleanup_net(),
(and thus rds_tcp_dev_event notification) is only called from put_net()
when all netns refcounts go to 0, but this cannot happen if the
rds_connection itself is holding a c_net ref that it expects to
release in rds_tcp_kill_sock.

Instead, the rds_tcp_kill_sock callback should make sure to
tear down state carefully, ensuring that the socket teardown
is only done after all data-structures and workqs that depend
on it are quiesced.

The original motivation for commit 8edc3aff ("rds: tcp: Take explicit
refcounts on struct net") was to resolve a race condition reported by
syzkaller where workqs for tx/rx/connect were triggered after the
namespace was deleted. Those worker threads should have been
cancelled/flushed before socket tear-down and indeed,
rds_conn_path_destroy() does try to sequence this by doing
     /* cancel cp_send_w */
     /* cancel cp_recv_w */
     /* flush cp_down_w */
     /* free data structures */
Here the "flush cp_down_w" will trigger rds_conn_shutdown and thus
invoke rds_tcp_conn_path_shutdown() to close the tcp socket, so that
we ought to have satisfied the requirement that "socket-close is
done after all other dependent state is quiesced". However,
rds_conn_shutdown has a bug in that it *always* triggers the reconnect
workq (and if connection is successful, we always restart tx/rx
workqs so with the right timing, we risk the race conditions reported
by syzkaller).

Netns deletion is like module teardown- no need to restart a
reconnect in this case. We can use the c_destroy_in_prog bit
to avoid restarting the reconnect.

Fixes: 8edc3aff ("rds: tcp: Take explicit refcounts on struct net")
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A side-effect of Commit c14b0366 ("rds: tcp: set linger to 1
when unloading a rds-tcp") is that we always send a RST on the tcp
connection for rds_conn_destroy(), so rds_tcp_conn_paths_destroy()
is not needed any more and is removed in this patch.
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When sending node local messages the code is using an 'mtu' of 66060
bytes to avoid unnecessary fragmentation. During situations of low
memory tipc_msg_build() may sometimes fail to allocate such large
buffers, resulting in unnecessary send failures. This can easily be
remedied by falling back to a smaller MTU, and then reassemble the
buffer chain as if the message were arriving from a remote node.

At the same time, we change the initial MTU setting of the broadcast
link to a lower value, so that large messages always are fragmented
into smaller buffers even when we run in single node mode. Apart from
obtaining the same advantage as for the 'fallback' solution above, this
turns out to give a significant performance improvement. This can
probably be explained with the __pskb_copy() operation performed on the
buffer for each recipient during reception. We found the optimal value
for this, considering the most relevant skb pool, to be 3744 bytes.
Acked-by: NYing Xue <ying.xue@ericsson.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the second tipc_rcv() call in tipc_udp_recv(). We have just
checked that the bearer is not up, and calling tipc_rcv() with a bearer
that is not up leads to a TIPC div-by-zero crash in
tipc_node_calculate_timer(). The crash is rare in practice, but can
happen like this:

  We're enabling a bearer, but it's not yet up and fully initialized.
  At the same time we receive a discovery packet, and in tipc_udp_recv()
  we end up calling tipc_rcv() with the not-yet-initialized bearer,
  causing later the div-by-zero crash in tipc_node_calculate_timer().

Jon Maloy explains the impact of removing the second tipc_rcv() call:
  "link setup in the worst case will be delayed until the next arriving
   discovery messages, 1 sec later, and this is an acceptable delay."

As the tipc_rcv() call is removed, just leave the function via the
rcu_out label, so that we will kfree_skb().

[   12.590450] Own node address <1.1.1>, network identity 1
[   12.668088] divide error: 0000 [#1] SMP
[   12.676952] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.2-dirty #1
[   12.679225] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[   12.682095] task: ffff8c2a761edb80 task.stack: ffffa41cc0cac000
[   12.684087] RIP: 0010:tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc]
[   12.686486] RSP: 0018:ffff8c2a7fc838a0 EFLAGS: 00010246
[   12.688451] RAX: 0000000000000000 RBX: ffff8c2a5b382600 RCX: 0000000000000000
[   12.691197] RDX: 0000000000000000 RSI: ffff8c2a5b382600 RDI: ffff8c2a5b382600
[   12.693945] RBP: ffff8c2a7fc838b0 R08: 0000000000000001 R09: 0000000000000001
[   12.696632] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8c2a5d8949d8
[   12.699491] R13: ffffffff95ede400 R14: 0000000000000000 R15: ffff8c2a5d894800
[   12.702338] FS:  0000000000000000(0000) GS:ffff8c2a7fc80000(0000) knlGS:0000000000000000
[   12.705099] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   12.706776] CR2: 0000000001bb9440 CR3: 00000000bd009001 CR4: 00000000003606e0
[   12.708847] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   12.711016] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   12.712627] Call Trace:
[   12.713390]  <IRQ>
[   12.714011]  tipc_node_check_dest+0x2e8/0x350 [tipc]
[   12.715286]  tipc_disc_rcv+0x14d/0x1d0 [tipc]
[   12.716370]  tipc_rcv+0x8b0/0xd40 [tipc]
[   12.717396]  ? minmax_running_min+0x2f/0x60
[   12.718248]  ? dst_alloc+0x4c/0xa0
[   12.718964]  ? tcp_ack+0xaf1/0x10b0
[   12.719658]  ? tipc_udp_is_known_peer+0xa0/0xa0 [tipc]
[   12.720634]  tipc_udp_recv+0x71/0x1d0 [tipc]
[   12.721459]  ? dst_alloc+0x4c/0xa0
[   12.722130]  udp_queue_rcv_skb+0x264/0x490
[   12.722924]  __udp4_lib_rcv+0x21e/0x990
[   12.723670]  ? ip_route_input_rcu+0x2dd/0xbf0
[   12.724442]  ? tcp_v4_rcv+0x958/0xa40
[   12.725039]  udp_rcv+0x1a/0x20
[   12.725587]  ip_local_deliver_finish+0x97/0x1d0
[   12.726323]  ip_local_deliver+0xaf/0xc0
[   12.726959]  ? ip_route_input_noref+0x19/0x20
[   12.727689]  ip_rcv_finish+0xdd/0x3b0
[   12.728307]  ip_rcv+0x2ac/0x360
[   12.728839]  __netif_receive_skb_core+0x6fb/0xa90
[   12.729580]  ? udp4_gro_receive+0x1a7/0x2c0
[   12.730274]  __netif_receive_skb+0x1d/0x60
[   12.730953]  ? __netif_receive_skb+0x1d/0x60
[   12.731637]  netif_receive_skb_internal+0x37/0xd0
[   12.732371]  napi_gro_receive+0xc7/0xf0
[   12.732920]  receive_buf+0x3c3/0xd40
[   12.733441]  virtnet_poll+0xb1/0x250
[   12.733944]  net_rx_action+0x23e/0x370
[   12.734476]  __do_softirq+0xc5/0x2f8
[   12.734922]  irq_exit+0xfa/0x100
[   12.735315]  do_IRQ+0x4f/0xd0
[   12.735680]  common_interrupt+0xa2/0xa2
[   12.736126]  </IRQ>
[   12.736416] RIP: 0010:native_safe_halt+0x6/0x10
[   12.736925] RSP: 0018:ffffa41cc0cafe90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff4d
[   12.737756] RAX: 0000000000000000 RBX: ffff8c2a761edb80 RCX: 0000000000000000
[   12.738504] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[   12.739258] RBP: ffffa41cc0cafe90 R08: 0000014b5b9795e5 R09: ffffa41cc12c7e88
[   12.740118] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
[   12.740964] R13: ffff8c2a761edb80 R14: 0000000000000000 R15: 0000000000000000
[   12.741831]  default_idle+0x2a/0x100
[   12.742323]  arch_cpu_idle+0xf/0x20
[   12.742796]  default_idle_call+0x28/0x40
[   12.743312]  do_idle+0x179/0x1f0
[   12.743761]  cpu_startup_entry+0x1d/0x20
[   12.744291]  start_secondary+0x112/0x120
[   12.744816]  secondary_startup_64+0xa5/0xa5
[   12.745367] Code: b9 f4 01 00 00 48 89 c2 48 c1 ea 02 48 3d d3 07 00
00 48 0f 47 d1 49 8b 0c 24 48 39 d1 76 07 49 89 14 24 48 89 d1 31 d2 48
89 df <48> f7 f1 89 c6 e8 81 6e ff ff 5b 41 5c 5d c3 66 90 66 2e 0f 1f
[   12.747527] RIP: tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc] RSP: ffff8c2a7fc838a0
[   12.748555] ---[ end trace 1399ab83390650fd ]---
[   12.749296] Kernel panic - not syncing: Fatal exception in interrupt
[   12.750123] Kernel Offset: 0x13200000 from 0xffffffff82000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   12.751215] Rebooting in 60 seconds..

Fixes: c9b64d49 ("tipc: add replicast peer discovery")
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>