linux.git/net/rds, branch v4.7-rc4

RDS: TCP: fix race windows in send-path quiescence by rds_tcp_accept_one()

2016-06-07T22:10:15+00:00

The send path needs to be quiesced before resetting callbacks from
rds_tcp_accept_one(), and commit eb192840266f ("RDS:TCP: Synchronize
rds_tcp_accept_one with rds_send_xmit when resetting t_sock") achieves
this using the c_state and RDS_IN_XMIT bit following the pattern
used by rds_conn_shutdown(). However this leaves the possibility
of a race window as shown in the sequence below
    take t_conn_lock in rds_tcp_conn_connect
    send outgoing syn to peer
    drop t_conn_lock in rds_tcp_conn_connect
    incoming from peer triggers rds_tcp_accept_one, conn is
	marked CONNECTING
    wait for RDS_IN_XMIT to quiesce any rds_send_xmit threads
    call rds_tcp_reset_callbacks
    [.. race-window where incoming syn-ack can cause the conn
	to be marked UP from rds_tcp_state_change ..]
    lock_sock called from rds_tcp_reset_callbacks, and we set
	t_sock to null
As soon as the conn is marked UP in the race-window above, rds_send_xmit()
threads will proceed to rds_tcp_xmit and may encounter a null-pointer
deref on the t_sock.

Given that rds_tcp_state_change() is invoked in softirq context, whereas
rds_tcp_reset_callbacks() is in workq context, and testing for RDS_IN_XMIT
after lock_sock could result in a deadlock with tcp_sendmsg, this
commit fixes the race by using a new c_state, RDS_TCP_RESETTING, which
will prevent a transition to RDS_CONN_UP from rds_tcp_state_change().

Signed-off-by: Sowmini Varadhan 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

RDS: TCP: Retransmit half-sent datagrams when switching sockets in rds_tcp_reset_callbacks

2016-06-07T22:10:15+00:00

When we switch a connection's sockets in rds_tcp_rest_callbacks,
any partially sent datagram must be retransmitted on the new
socket so that the receiver can correctly reassmble the RDS
datagram. Use rds_send_reset() which is designed for this purpose.

Signed-off-by: Sowmini Varadhan 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

RDS: TCP: Add/use rds_tcp_reset_callbacks to reset tcp socket safely

2016-06-07T22:10:15+00:00

When rds_tcp_accept_one() has to replace the existing tcp socket
with a newer tcp socket (duelling-syn resolution), it must lock_sock()
to suppress the rds_tcp_data_recv() path while callbacks are being
changed.  Also, existing RDS datagram reassembly state must be reset,
so that the next datagram on the new socket  does not have corrupted
state. Similarly when resetting the newly accepted socket, appropriate
locks and synchronization is needed.

This commit ensures correct synchronization by invoking
kernel_sock_shutdown to reset a newly accepted sock, and by taking
appropriate lock_sock()s (for old and new sockets) when resetting
existing callbacks.

Signed-off-by: Sowmini Varadhan 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

rds: fix an infoleak in rds_inc_info_copy

2016-06-03T04:32:37+00:00

The last field "flags" of object "minfo" is not initialized.
Copying this object out may leak kernel stack data.
Assign 0 to it to avoid leak.

Signed-off-by: Kangjie Lu 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

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

2016-05-21T03:01:26+00:00

Pull networking fixes and more updates from David Miller:

 1) Tunneling fixes from Tom Herbert and Alexander Duyck.

 2) AF_UNIX updates some struct sock bit fields with the socket lock,
    whereas setsockopt() sets overlapping ones with locking.  Seperate
    out the synchronized vs.  the AF_UNIX unsynchronized ones to avoid
    corruption.  From Andrey Ryabinin.

 3) Mount BPF filesystem with mount_nodev rather than mount_ns, from
    Eric Biederman.

 4) A couple kmemdup conversions, from Muhammad Falak R Wani.

 5) BPF verifier fixes from Alexei Starovoitov.

 6) Don't let tunneled UDP packets get stuck in socket queues, if
    something goes wrong during the encapsulation just drop the packet
    rather than signalling an error up the call stack.  From Hannes
    Frederic Sowa.

 7) SKB ref after free in batman-adv, from Florian Westphal.

 8) TCP iSCSI, ocfs2, rds, and tipc have to disable BH in it's TCP
    callbacks since the TCP stack runs pre-emptibly now.  From Eric
    Dumazet.

 9) Fix crash in fixed_phy_add, from Rabin Vincent.

10) Fix length checks in xen-netback, from Paul Durrant.

11) Fix mixup in KEY vs KEYID macsec attributes, from Sabrina Dubroca.

12) RDS connection spamming bug fixes from Sowmini Varadhan

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (152 commits)
  net: suppress warnings on dev_alloc_skb
  uapi glibc compat: fix compilation when !__USE_MISC in glibc
  udp: prevent skbs lingering in tunnel socket queues
  bpf: teach verifier to recognize imm += ptr pattern
  bpf: support decreasing order in direct packet access
  net: usb: ch9200: use kmemdup
  ps3_gelic: use kmemdup
  net:liquidio: use kmemdup
  bpf: Use mount_nodev not mount_ns to mount the bpf filesystem
  net: cdc_ncm: update datagram size after changing mtu
  tuntap: correctly wake up process during uninit
  intel: Add support for IPv6 IP-in-IP offload
  ip6_gre: Do not allow segmentation offloads GRE_CSUM is enabled with FOU/GUE
  RDS: TCP: Avoid rds connection churn from rogue SYNs
  RDS: TCP: rds_tcp_accept_worker() must exit gracefully when terminating rds-tcp
  net: sock: move ->sk_shutdown out of bitfields.
  ipv6: Don't reset inner headers in ip6_tnl_xmit
  ip4ip6: Support for GSO/GRO
  ip6ip6: Support for GSO/GRO
  ipv6: Set features for IPv6 tunnels
  ...

RDS: TCP: Avoid rds connection churn from rogue SYNs

2016-05-20T23:19:57+00:00

When a rogue SYN is received after the connection arbitration
algorithm has converged, the incoming SYN should not needlessly
quiesce the transmit path, and it should not result in needless
TCP connection resets due to re-execution of the connection
arbitration logic.

Signed-off-by: Sowmini Varadhan 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

RDS: TCP: rds_tcp_accept_worker() must exit gracefully when terminating rds-tcp

2016-05-20T23:19:57+00:00

There are two instances where we want to terminate RDS-TCP: when
exiting the netns or during module unload. In either case, the
termination sequence is to stop the listen socket, mark the
rtn->rds_tcp_listen_sock as null, and flush any accept workqs.
Thus any workqs that get flushed at this point will encounter a
null rds_tcp_listen_sock, and must exit gracefully to allow
the RDS-TCP termination to complete successfully.

Signed-off-by: Sowmini Varadhan 
Acked-by: Santosh Shilimkar 
Signed-off-by: David S. Miller

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

2016-05-20T21:35:07+00:00

Pull rdma updates from Doug Ledford:
 "Primary 4.7 merge window changes

   - Updates to the new Intel X722 iWARP driver
   - Updates to the hfi1 driver
   - Fixes for the iw_cxgb4 driver
   - Misc core fixes
   - Generic RDMA READ/WRITE API addition
   - SRP updates
   - Misc ipoib updates
   - Minor mlx5 updates"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (148 commits)
  IB/mlx5: Fire the CQ completion handler from tasklet
  net/mlx5_core: Use tasklet for user-space CQ completion events
  IB/core: Do not require CAP_NET_ADMIN for packet sniffing
  IB/mlx4: Fix unaligned access in send_reply_to_slave
  IB/mlx5: Report Scatter FCS device capability when supported
  IB/mlx5: Add Scatter FCS support for Raw Packet QP
  IB/core: Add Scatter FCS create flag
  IB/core: Add Raw Scatter FCS device capability
  IB/core: Add extended device capability flags
  i40iw: pass hw_stats by reference rather than by value
  i40iw: Remove unnecessary synchronize_irq() before free_irq()
  i40iw: constify i40iw_vf_cqp_ops structure
  IB/mlx5: Add UARs write-combining and non-cached mapping
  IB/mlx5: Allow mapping the free running counter on PROT_EXEC
  IB/mlx4: Use list_for_each_entry_safe
  IB/SA: Use correct free function
  IB/core: Fix a potential array overrun in CMA and SA agent
  IB/core: Remove unnecessary check in ibnl_rcv_msg
  IB/IWPM: Fix a potential skb leak
  RDMA/nes: replace custom print_hex_dump()
  ...

rds: tcp: block BH in TCP callbacks

2016-05-19T18:36:49+00:00

TCP stack can now run from process context.

Use read_lock_bh(&sk->sk_callback_lock) variant to restore previous
assumption.

Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog")
Fixes: d41a69f1d390 ("tcp: make tcp_sendmsg() aware of socket backlog")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

IB/core: Add passing an offset into the SG to ib_map_mr_sg

2016-05-13T17:37:11+00:00

Signed-off-by: Christoph Hellwig 
Tested-by: Steve Wise 
Reviewed-by: Bart Van Assche 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Steve Wise 
Signed-off-by: Doug Ledford