linux-stable.git/net/sctp, branch v5.4

inet: stop leaking jiffies on the wire

2019-11-01T21:57:52+00:00

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: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet 
Reported-by: Thiemo Nagel 
Signed-off-by: David S. Miller

net: use skb_queue_empty_lockless() in busy poll contexts

2019-10-28T20:33:41+00:00

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: Eric Dumazet 
Signed-off-by: David S. Miller

net: use skb_queue_empty_lockless() in poll() handlers

2019-10-28T20:33:41+00:00

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-10-19T21:09:11+00:00

Pull networking fixes from David Miller:
 "I was battling a cold after some recent trips, so quite a bit piled up
  meanwhile, sorry about that.

  Highlights:

   1) Fix fd leak in various bpf selftests, from Brian Vazquez.

   2) Fix crash in xsk when device doesn't support some methods, from
      Magnus Karlsson.

   3) Fix various leaks and use-after-free in rxrpc, from David Howells.

   4) Fix several SKB leaks due to confusion of who owns an SKB and who
      should release it in the llc code. From Eric Biggers.

   5) Kill a bunc of KCSAN warnings in TCP, from Eric Dumazet.

   6) Jumbo packets don't work after resume on r8169, as the BIOS resets
      the chip into non-jumbo mode during suspend. From Heiner Kallweit.

   7) Corrupt L2 header during MPLS push, from Davide Caratti.

   8) Prevent possible infinite loop in tc_ctl_action, from Eric
      Dumazet.

   9) Get register bits right in bcmgenet driver, based upon chip
      version. From Florian Fainelli.

  10) Fix mutex problems in microchip DSA driver, from Marek Vasut.

  11) Cure race between route lookup and invalidation in ipv4, from Wei
      Wang.

  12) Fix performance regression due to false sharing in 'net'
      structure, from Eric Dumazet"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (145 commits)
  net: reorder 'struct net' fields to avoid false sharing
  net: dsa: fix switch tree list
  net: ethernet: dwmac-sun8i: show message only when switching to promisc
  net: aquantia: add an error handling in aq_nic_set_multicast_list
  net: netem: correct the parent's backlog when corrupted packet was dropped
  net: netem: fix error path for corrupted GSO frames
  macb: propagate errors when getting optional clocks
  xen/netback: fix error path of xenvif_connect_data()
  net: hns3: fix mis-counting IRQ vector numbers issue
  net: usb: lan78xx: Connect PHY before registering MAC
  vsock/virtio: discard packets if credit is not respected
  vsock/virtio: send a credit update when buffer size is changed
  mlxsw: spectrum_trap: Push Ethernet header before reporting trap
  net: ensure correct skb->tstamp in various fragmenters
  net: bcmgenet: reset 40nm EPHY on energy detect
  net: bcmgenet: soft reset 40nm EPHYs before MAC init
  net: phy: bcm7xxx: define soft_reset for 40nm EPHY
  net: bcmgenet: don't set phydev->link from MAC
  net: Update address for MediaTek ethernet driver in MAINTAINERS
  ipv4: fix race condition between route lookup and invalidation
  ...

sctp: change sctp_prot .no_autobind with true

2019-10-16T03:37:51+00:00

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: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

net: sctp: Rename fallthrough label to unhandled

2019-10-11T16:26:05+00:00

fallthrough will become a pseudo reserved keyword so this only use of
fallthrough is better renamed to allow it.

Signed-off-by: Joe Perches 
Reviewed-by: Nick Desaulniers 
Reviewed-by: Kees Cook 
Acked-by: Neil Horman 
Signed-off-by: Linus Torvalds

net: silence KCSAN warnings about sk->sk_backlog.len reads

2019-10-10T04:43:00+00:00

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: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: Jakub Kicinski

net: silence KCSAN warnings around sk_add_backlog() calls

2019-10-10T04:42:59+00:00

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: Eric Dumazet 
Reported-by: syzbot 
Signed-off-by: Jakub Kicinski

sctp: add chunks to sk_backlog when the newsk sk_socket is not set

2019-10-09T23:27:04+00:00

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: d452930fd3b9 ("selinux: Add SCTP support")
Reported-by: Ying Xu 
Suggested-by: Marcelo Ricardo Leitner 
Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Acked-by: Neil Horman 
Signed-off-by: Jakub Kicinski

netfilter: drop bridge nf reset from nf_reset

2019-10-01T16:42:15+00:00

commit 174e23810cd31
("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: Eric Dumazet 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso