This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow,
as some modules currently pass a net argument without a socket to
ip6_dst_lookup. This is equivalent to commit 343d60aa ("ipv6: change
ipv6_stub_impl.ipv6_dst_lookup to take net argument").
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Note that the sysctl write accessor functions guarantee that:
  net->ipv4.sysctl_ip_prot_sock <= net->ipv4.ip_local_ports.range[0]
invariant is maintained, and as such the max() in selinux hooks is actually spurious.

ie. even though
  if (snum < max(inet_prot_sock(sock_net(sk)), low) || snum > high) {
per logic is the same as
  if ((snum < inet_prot_sock(sock_net(sk)) && snum < low) || snum > high) {
it is actually functionally equivalent to:
  if (snum < low || snum > high) {
which is equivalent to:
  if (snum < inet_prot_sock(sock_net(sk)) || snum < low || snum > high) {
even though the first clause is spurious.

But we want to hold on to it in case we ever want to change what what
inet_port_requires_bind_service() means (for example by changing
it from a, by default, [0..1024) range to some sort of set).

Test: builds, git 'grep inet_prot_sock' finds no other references
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It already existed in part of the function, but move it
to a higher level and use it consistently throughout.

Safe since sk is never written to.
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to fix a data-race reported by syzbot:

  BUG: KCSAN: data-race in sctp_assoc_migrate / sctp_hash_obj

  write to 0xffff8880b67c0020 of 8 bytes by task 18908 on cpu 1:
    sctp_assoc_migrate+0x1a6/0x290 net/sctp/associola.c:1091
    sctp_sock_migrate+0x8aa/0x9b0 net/sctp/socket.c:9465
    sctp_accept+0x3c8/0x470 net/sctp/socket.c:4916
    inet_accept+0x7f/0x360 net/ipv4/af_inet.c:734
    __sys_accept4+0x224/0x430 net/socket.c:1754
    __do_sys_accept net/socket.c:1795 [inline]
    __se_sys_accept net/socket.c:1792 [inline]
    __x64_sys_accept+0x4e/0x60 net/socket.c:1792
    do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

  read to 0xffff8880b67c0020 of 8 bytes by task 12003 on cpu 0:
    sctp_hash_obj+0x4f/0x2d0 net/sctp/input.c:894
    rht_key_get_hash include/linux/rhashtable.h:133 [inline]
    rht_key_hashfn include/linux/rhashtable.h:159 [inline]
    rht_head_hashfn include/linux/rhashtable.h:174 [inline]
    head_hashfn lib/rhashtable.c:41 [inline]
    rhashtable_rehash_one lib/rhashtable.c:245 [inline]
    rhashtable_rehash_chain lib/rhashtable.c:276 [inline]
    rhashtable_rehash_table lib/rhashtable.c:316 [inline]
    rht_deferred_worker+0x468/0xab0 lib/rhashtable.c:420
    process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
    worker_thread+0xa0/0x800 kernel/workqueue.c:2415
    kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

It was caused by rhashtable access asoc->base.sk when sctp_assoc_migrate
is changing its value. However, what rhashtable wants is netns from asoc
base.sk, and for an asoc, its netns won't change once set. So we can
simply fix it by caching netns since created.

Fixes: d6c0256a ("sctp: add the rhashtable apis for sctp global transport hashtable")
Reported-by: syzbot+e3b35fe7918ff0ee474e@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

In the implementation of sctp_sf_do_5_2_4_dupcook() the allocated
new_asoc is leaked if security_sctp_assoc_request() fails. Release it
via sctp_association_free().

Fixes: 2277c7cd ("sctp: Add LSM hooks")
Signed-off-by: NNavid Emamdoost <navid.emamdoost@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

Section 7.2 of rfc7829: "Peer Address Thresholds (SCTP_PEER_ADDR_THLDS)
Socket Option" extends 'struct sctp_paddrthlds' with 'spt_pathcpthld'
added to allow a user to change ps_retrans per sock/asoc/transport, as
other 2 paddrthlds: pf_retrans, pathmaxrxt.

Note: to not break the user's program, here to support pf_retrans dump
and setting by adding a new sockopt SCTP_PEER_ADDR_THLDS_V2, and a new
structure sctp_paddrthlds_v2 instead of extending sctp_paddrthlds.

Also, when setting ps_retrans, the value is not allowed to be greater
than pf_retrans.

v1->v2:
  - use SCTP_PEER_ADDR_THLDS_V2 to set/get pf_retrans instead,
    as Marcelo and David Laight suggested.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a new feature defined in section 5 of rfc7829: "Primary Path
Switchover". By introducing a new tunable parameter:

  Primary.Switchover.Max.Retrans (PSMR)

The primary path will be changed to another active path when the path
error counter on the old primary path exceeds PSMR, so that "the SCTP
sender is allowed to continue data transmission on a new working path
even when the old primary destination address becomes active again".

This patch is to add this tunable parameter, 'ps_retrans' per netns,
sock, asoc and transport. It also allows a user to change ps_retrans
per netns by sysctl, and ps_retrans per sock/asoc/transport will be
initialized with it.

The check will be done in sctp_do_8_2_transport_strike() when this
feature is enabled.

Note this feature is disabled by initializing 'ps_retrans' per netns
as 0xffff by default, and its value can't be less than 'pf_retrans'
when changing by sysctl.

v3->v4:
  - add define SCTP_PS_RETRANS_MAX 0xffff, and use it on extra2 of
    sysctl 'ps_retrans'.
  - add a new entry for ps_retrans on ip-sysctl.txt.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a sockopt defined in section 7.3 of rfc7829: "Exposing
the Potentially Failed Path State", by which users can change
pf_expose per sock and asoc.

The new sockopt SCTP_EXPOSE_POTENTIALLY_FAILED_STATE is also
known as SCTP_EXPOSE_PF_STATE for short.

v2->v3:
  - return -EINVAL if params.assoc_value > SCTP_PF_EXPOSE_MAX.
  - define SCTP_EXPOSE_PF_STATE SCTP_EXPOSE_POTENTIALLY_FAILED_STATE.
v3->v4:
  - improve changelog.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SCTP Quick failover draft section 5.1, point 5 has been removed
from rfc7829. Instead, "the sender SHOULD (i) notify the Upper
Layer Protocol (ULP) about this state transition", as said in
section 3.2, point 8.

So this patch is to add SCTP_ADDR_POTENTIALLY_FAILED, defined
in section 7.1, "which is reported if the affected address
becomes PF". Also remove transport cwnd's update when moving
from PF back to ACTIVE , which is no longer in rfc7829 either.

Note that ulp_notify will be set to false if asoc->expose is
not 'enabled', according to last patch.

v2->v3:
  - define SCTP_ADDR_PF SCTP_ADDR_POTENTIALLY_FAILED.
v3->v4:
  - initialize spc_state with SCTP_ADDR_AVAILABLE, as Marcelo suggested.
  - check asoc->pf_expose in sctp_assoc_control_transport(), as Marcelo
    suggested.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As said in rfc7829, section 3, point 12:

  The SCTP stack SHOULD expose the PF state of its destination
  addresses to the ULP as well as provide the means to notify the
  ULP of state transitions of its destination addresses from
  active to PF, and vice versa.  However, it is recommended that
  an SCTP stack implementing SCTP-PF also allows for the ULP to be
  kept ignorant of the PF state of its destinations and the
  associated state transitions, thus allowing for retention of the
  simpler state transition model of [RFC4960] in the ULP.

Not only does it allow to expose the PF state to ULP, but also
allow to ignore sctp-pf to ULP.

So this patch is to add pf_expose per netns, sock and asoc. And in
sctp_assoc_control_transport(), ulp_notify will be set to false if
asoc->expose is not 'enabled' in next patch.

It also allows a user to change pf_expose per netns by sysctl, and
pf_expose per sock and asoc will be initialized with it.

Note that pf_expose also works for SCTP_GET_PEER_ADDR_INFO sockopt,
to not allow a user to query the state of a sctp-pf peer address
when pf_expose is 'disabled', as said in section 7.3.

v1->v2:
  - Fix a build warning noticed by Nathan Chancellor.
v2->v3:
  - set pf_expose to UNUSED by default to keep compatible with old
    applications.
v3->v4:
  - add a new entry for pf_expose on ip-sysctl.txt, as Marcelo suggested.
  - change this patch to 1/5, and move sctp_assoc_control_transport
    change into 2/5, as Marcelo suggested.
  - use SCTP_PF_EXPOSE_UNSET instead of SCTP_PF_EXPOSE_UNUSED, and
    set SCTP_PF_EXPOSE_UNSET to 0 in enum, as Marcelo suggested.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_max_ack_backlog can be read without any lock being held
at least in TCP/DCCP cases.

We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_ack_backlog can be read without any lock being held.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Writers are holding a lock, but many readers do not.

Following patch will add appropriate barriers in
sk_acceptq_removed() and sk_acceptq_added().
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Historically linux tried to stick to RFC 791, 1122, 2003
for IPv4 ID field generation.

RFC 6864 made clear that no matter how hard we try,
we can not ensure unicity of IP ID within maximum
lifetime for all datagrams with a given source
address/destination address/protocol tuple.

Linux uses a per socket inet generator (inet_id), initialized
at connection startup with a XOR of 'jiffies' and other
fields that appear clear on the wire.

Thiemo Nagel pointed that this strategy is a privacy
concern as this provides 16 bits of entropy to fingerprint
devices.

Let's switch to a random starting point, this is just as
good as far as RFC 6864 is concerned and does not leak
anything critical.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NThiemo Nagel <tnagel@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Busy polling usually runs without locks.
Let's use skb_queue_empty_lockless() instead of skb_queue_empty()

Also uses READ_ONCE() in __skb_try_recv_datagram() to address
a similar potential problem.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

syzbot reported a memory leak:

  BUG: memory leak, unreferenced object 0xffff888120b3d380 (size 64):
  backtrace:

    [...] slab_alloc mm/slab.c:3319 [inline]
    [...] kmem_cache_alloc+0x13f/0x2c0 mm/slab.c:3483
    [...] sctp_bucket_create net/sctp/socket.c:8523 [inline]
    [...] sctp_get_port_local+0x189/0x5a0 net/sctp/socket.c:8270
    [...] sctp_do_bind+0xcc/0x200 net/sctp/socket.c:402
    [...] sctp_bindx_add+0x4b/0xd0 net/sctp/socket.c:497
    [...] sctp_setsockopt_bindx+0x156/0x1b0 net/sctp/socket.c:1022
    [...] sctp_setsockopt net/sctp/socket.c:4641 [inline]
    [...] sctp_setsockopt+0xaea/0x2dc0 net/sctp/socket.c:4611
    [...] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3147
    [...] __sys_setsockopt+0x10f/0x220 net/socket.c:2084
    [...] __do_sys_setsockopt net/socket.c:2100 [inline]

It was caused by when sending msgs without binding a port, in the path:
inet_sendmsg() -> inet_send_prepare() -> inet_autobind() ->
.get_port/sctp_get_port(), sp->bind_hash will be set while bp->port is
not. Later when binding another port by sctp_setsockopt_bindx(), a new
bucket will be created as bp->port is not set.

sctp's autobind is supposed to call sctp_autobind() where it does all
things including setting bp->port. Since sctp_autobind() is called in
sctp_sendmsg() if the sk is not yet bound, it should have skipped the
auto bind.

THis patch is to avoid calling inet_autobind() in inet_send_prepare()
by changing sctp_prot .no_autobind with true, also remove the unused
.get_port.

Reported-by: syzbot+d44f7bbebdea49dbc84a@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fallthrough will become a pseudo reserved keyword so this only use of
fallthrough is better renamed to allow it.
Signed-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sk->sk_backlog.len can be written by BH handlers, and read
from process contexts in a lockless way.

Note the write side should also use WRITE_ONCE() or a variant.
We need some agreement about the best way to do this.

syzbot reported :

BUG: KCSAN: data-race in tcp_add_backlog / tcp_grow_window.isra.0

write to 0xffff88812665f32c of 4 bytes by interrupt on cpu 1:
 sk_add_backlog include/net/sock.h:934 [inline]
 tcp_add_backlog+0x4a0/0xcc0 net/ipv4/tcp_ipv4.c:1737
 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925
 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418

read to 0xffff88812665f32c of 4 bytes by task 7292 on cpu 0:
 tcp_space include/net/tcp.h:1373 [inline]
 tcp_grow_window.isra.0+0x6b/0x480 net/ipv4/tcp_input.c:413
 tcp_event_data_recv+0x68f/0x990 net/ipv4/tcp_input.c:717
 tcp_rcv_established+0xbfe/0xf50 net/ipv4/tcp_input.c:5618
 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x135/0x1e0 net/core/sock.c:2427
 release_sock+0x61/0x160 net/core/sock.c:2943
 tcp_recvmsg+0x63b/0x1a30 net/ipv4/tcp.c:2181
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_recvmsg+0x92/0xb0 net/socket.c:885
 sock_read_iter+0x15f/0x1e0 net/socket.c:967
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7292 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

sk_add_backlog() callers usually read sk->sk_rcvbuf without
owning the socket lock. This means sk_rcvbuf value can
be changed by other cpus, and KCSAN complains.

Add READ_ONCE() annotations to document the lockless nature
of these reads.

Note that writes over sk_rcvbuf should also use WRITE_ONCE(),
but this will be done in separate patches to ease stable
backports (if we decide this is relevant for stable trees).

BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg

write to 0xffff88812ab369f8 of 8 bytes by interrupt on cpu 1:
 __sk_add_backlog include/net/sock.h:902 [inline]
 sk_add_backlog include/net/sock.h:933 [inline]
 tcp_add_backlog+0x45a/0xcc0 net/ipv4/tcp_ipv4.c:1737
 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925
 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418

read to 0xffff88812ab369f8 of 8 bytes by task 7271 on cpu 0:
 tcp_recvmsg+0x470/0x1a30 net/ipv4/tcp.c:2047
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_recvmsg+0x92/0xb0 net/socket.c:885
 sock_read_iter+0x15f/0x1e0 net/socket.c:967
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446
 ksys_read+0xd5/0x1b0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x4c/0x60 fs/read_write.c:595
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7271 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

This patch is to add a new event SCTP_SEND_FAILED_EVENT described in
rfc6458#section-6.1.11. It's a update of SCTP_SEND_FAILED event:

  struct sctp_sndrcvinfo ssf_info is replaced with
  struct sctp_sndinfo ssfe_info in struct sctp_send_failed_event.

SCTP_SEND_FAILED is being deprecated, but we don't remove it in this
patch. Both are being processed in sctp_datamsg_destroy() when the
corresp event flag is set.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

sctp_ulpevent_nofity_peer_addr_change() would be called in
sctp_assoc_set_primary() to send SCTP_ADDR_MADE_PRIM event
when this transport is set to the primary path of the asoc.

This event is described in rfc6458#section-6.1.2:

  SCTP_ADDR_MADE_PRIM:  This address has now been made the primary
     destination address.  This notification is provided whenever an
     address is made primary.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

sctp_ulpevent_nofity_peer_addr_change() is called in
sctp_assoc_rm_peer() to send SCTP_ADDR_REMOVED event
when this transport is removed from the asoc.

This event is described in rfc6458#section-6.1.2:

  SCTP_ADDR_REMOVED:  The address is no longer part of the
     association.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

A helper sctp_ulpevent_nofity_peer_addr_change() will be extracted
to make peer_addr_change event and enqueue it, and the helper will
be called in sctp_assoc_add_peer() to send SCTP_ADDR_ADDED event.

This event is described in rfc6458#section-6.1.2:

  SCTP_ADDR_ADDED:  The address is now part of the association.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

This patch is to fix a NULL-ptr deref in selinux_socket_connect_helper:

  [...] kasan: GPF could be caused by NULL-ptr deref or user memory access
  [...] RIP: 0010:selinux_socket_connect_helper+0x94/0x460
  [...] Call Trace:
  [...]  selinux_sctp_bind_connect+0x16a/0x1d0
  [...]  security_sctp_bind_connect+0x58/0x90
  [...]  sctp_process_asconf+0xa52/0xfd0 [sctp]
  [...]  sctp_sf_do_asconf+0x785/0x980 [sctp]
  [...]  sctp_do_sm+0x175/0x5a0 [sctp]
  [...]  sctp_assoc_bh_rcv+0x285/0x5b0 [sctp]
  [...]  sctp_backlog_rcv+0x482/0x910 [sctp]
  [...]  __release_sock+0x11e/0x310
  [...]  release_sock+0x4f/0x180
  [...]  sctp_accept+0x3f9/0x5a0 [sctp]
  [...]  inet_accept+0xe7/0x720

It was caused by that the 'newsk' sk_socket was not set before going to
security sctp hook when processing asconf chunk with SCTP_PARAM_ADD_IP
or SCTP_PARAM_SET_PRIMARY:

  inet_accept()->
    sctp_accept():
      lock_sock():
          lock listening 'sk'
                                          do_softirq():
                                            sctp_rcv():  <-- [1]
                                                asconf chunk arrives and
                                                enqueued in 'sk' backlog
      sctp_sock_migrate():
          set asoc's sk to 'newsk'
      release_sock():
          sctp_backlog_rcv():
            lock 'newsk'
            sctp_process_asconf()  <-- [2]
            unlock 'newsk'
    sock_graft():
        set sk_socket  <-- [3]

As it shows, at [1] the asconf chunk would be put into the listening 'sk'
backlog, as accept() was holding its sock lock. Then at [2] asconf would
get processed with 'newsk' as asoc's sk had been set to 'newsk'. However,
'newsk' sk_socket is not set until [3], while selinux_sctp_bind_connect()
would deref it, then kernel crashed.

Here to fix it by adding the chunk to sk_backlog until newsk sk_socket is
set when .accept() is done.

Note that sk->sk_socket can be NULL when the sock is closed, so SOCK_DEAD
flag is also needed to check in sctp_newsk_ready().

Thanks to Ondrej for reviewing the code.

Fixes: d452930f ("selinux: Add SCTP support")
Reported-by: NYing Xu <yinxu@redhat.com>
Suggested-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

commit 174e2381
("sk_buff: drop all skb extensions on free and skb scrubbing") made napi
recycle always drop skb extensions.  The additional skb_ext_del() that is
performed via nf_reset on napi skb recycle is not needed anymore.

Most nf_reset() calls in the stack are there so queued skb won't block
'rmmod nf_conntrack' indefinitely.

This removes the skb_ext_del from nf_reset, and renames it to a more
fitting nf_reset_ct().

In a few selected places, add a call to skb_ext_reset to make sure that
no active extensions remain.

I am submitting this for "net", because we're still early in the release
cycle.  The patch applies to net-next too, but I think the rename causes
needless divergence between those trees.
Suggested-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Currently, ip6_xmit() sets skb->priority based on sk->sk_priority

This is not desirable for TCP since TCP shares the same ctl socket
for a given netns. We want to be able to send RST or ACK packets
with a non zero skb->priority.

This patch has no functional change.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is one memory leak bug report:
BUG: memory leak
unreferenced object 0xffff8881dc4c5ec0 (size 40):
  comm "syz-executor.0", pid 5673, jiffies 4298198457 (age 27.578s)
  hex dump (first 32 bytes):
    02 00 00 00 81 88 ff ff 00 00 00 00 00 00 00 00  ................
    f8 63 3d c1 81 88 ff ff 00 00 00 00 00 00 00 00  .c=.............
  backtrace:
    [<0000000072006339>] sctp_get_port_local+0x2a1/0xa00 [sctp]
    [<00000000c7b379ec>] sctp_do_bind+0x176/0x2c0 [sctp]
    [<000000005be274a2>] sctp_bind+0x5a/0x80 [sctp]
    [<00000000b66b4044>] inet6_bind+0x59/0xd0 [ipv6]
    [<00000000c68c7f42>] __sys_bind+0x120/0x1f0 net/socket.c:1647
    [<000000004513635b>] __do_sys_bind net/socket.c:1658 [inline]
    [<000000004513635b>] __se_sys_bind net/socket.c:1656 [inline]
    [<000000004513635b>] __x64_sys_bind+0x3e/0x50 net/socket.c:1656
    [<0000000061f2501e>] do_syscall_64+0x72/0x2e0 arch/x86/entry/common.c:296
    [<0000000003d1e05e>] entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is because in sctp_do_bind, if sctp_get_port_local is to
create hash bucket successfully, and sctp_add_bind_addr failed
to bind address, e.g return -ENOMEM, so memory leak found, it
needs to destroy allocated bucket.
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NMao Wenan <maowenan@huawei.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are more parentheses in if clause when call sctp_get_port_local
in sctp_do_bind, and redundant assignment to 'ret'. This patch is to
do cleanup.
Signed-off-by: NMao Wenan <maowenan@huawei.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently sctp_get_port_local() returns a long
which is either 0,1 or a pointer casted to long.
It's neither of the callers use the return value since
commit 62208f12 ("net: sctp: simplify sctp_get_port").
Now two callers are sctp_get_port and sctp_do_bind,
they actually assumend a casted to an int was the same as
a pointer casted to a long, and they don't save the return
value just check whether it is zero or non-zero, so
it would better change return type from long to int for
sctp_get_port_local.
Signed-off-by: NMao Wenan <maowenan@huawei.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The '.exit' functions from 'pernet_operations' structure should be marked
as __net_exit, not __net_init.

Fixes: 8e2d61e0 ("sctp: fix race on protocol/netns initialization")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This issue causes SCTP_PEER_ADDR_THLDS sockopt not to be able to dump
a transport thresholds info.

Fix it by adding 'goto' put_user in sctp_getsockopt_paddr_thresholds.

Fixes: 8add543e ("sctp: add SCTP_FUTURE_ASSOC for SCTP_PEER_ADDR_THLDS sockopt")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Transport should use its own pf_retrans to do the error_count
check, instead of asoc's. Otherwise, it's meaningless to make
pf_retrans per transport.

Fixes: 5aa93bcf ("sctp: Implement quick failover draft from tsvwg")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SCTP_ECN_SUPPORTED sockopt will be added to allow users to change
ep ecn flag, and it's similar with other feature flags.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sysctl net.sctp.ecn_enable is added in this patch. It will allow
users to change the default sctp ecn flag, net.sctp.ecn_enable.

This feature was also required on this thread:

  http://lkml.iu.edu/hypermail/linux/kernel/0812.1/01858.htmlSigned-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to add ecn flag for both netns_sctp and sctp_endpoint,
net->sctp.ecn_enable is set 1 by default, and ep->ecn_enable will
be initialized with net->sctp.ecn_enable.

asoc->peer.ecn_capable will be set during negotiation only when
ep->ecn_enable is set on both sides.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The netns sctp feature flags shouldn't work as a global switch,
which is mostly like a firewall/netfilter's job. Also, it will
break asoc as it discard or accept chunks incorrectly when net
sctp.x_enable is changed after the asoc is created.

Since each type of chunk's processing function will check the
corresp asoc's feature flag, this 'global switch' should be
removed, and net sctp.x_enable will only work as the default
feature flags for the future sctp sockets/endpoints.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SCTP_AUTH_SUPPORTED sockopt is used to set enpoint's auth
flag. With this feature, each endpoint will have its own
flag for its future asoc's auth_capable, instead of netns
auth flag.

Note that when both ep's auth_enable is enabled, endpoint
auth related data should be initialized. If asconf_enable
is also set, SCTP_CID_ASCONF/SCTP_CID_ASCONF_ACK should
be added into auth_chunk_list.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to factor out sctp_auth_init and sctp_auth_free
functions, and sctp_auth_init will also be used in the next
patch for SCTP_AUTH_SUPPORTED sockopt.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sctp has per endpoint auth flag and per asoc auth flag, and
the asoc one should be checked when coming to asoc and the
endpoint one should be checked when coming to endpoint.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>