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  1. 20 1月, 2015 7 次提交
  3. 18 1月, 2015 1 次提交
    • D
      net: sctp: fix race for one-to-many sockets in sendmsg's auto associate · 2061dcd6
      由 Daniel Borkmann 提交于 
      I.e. one-to-many sockets in SCTP are not required to explicitly
call into connect(2) or sctp_connectx(2) prior to data exchange.
Instead, they can directly invoke sendmsg(2) and the SCTP stack
will automatically trigger connection establishment through 4WHS
via sctp_primitive_ASSOCIATE(). However, this in its current
implementation is racy: INIT is being sent out immediately (as
it cannot be bundled anyway) and the rest of the DATA chunks are
queued up for later xmit when connection is established, meaning
sendmsg(2) will return successfully. This behaviour can result
in an undesired side-effect that the kernel made the application
think the data has already been transmitted, although none of it
has actually left the machine, worst case even after close(2)'ing
the socket.

Instead, when the association from client side has been shut down
e.g. first gracefully through SCTP_EOF and then close(2), the
client could afterwards still receive the server's INIT_ACK due
to a connection with higher latency. This INIT_ACK is then considered
out of the blue and hence responded with ABORT as there was no
alive assoc found anymore. This can be easily reproduced f.e.
with sctp_test application from lksctp. One way to fix this race
is to wait for the handshake to actually complete.

The fix defers waiting after sctp_primitive_ASSOCIATE() and
sctp_primitive_SEND() succeeded, so that DATA chunks cooked up
from sctp_sendmsg() have already been placed into the output
queue through the side-effect interpreter, and therefore can then
be bundeled together with COOKIE_ECHO control chunks.

strace from example application (shortened):

socket(PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP) = 3
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(1)=[{"hello", 5}], msg_controllen=0, msg_flags=0}, 0) = 5
sendmsg(3, {msg_name(28)={sa_family=AF_INET, sin_port=htons(8888), sin_addr=inet_addr("192.168.1.115")},
           msg_iov(0)=[], msg_controllen=48, {cmsg_len=48, cmsg_level=0x84 /* SOL_??? */, cmsg_type=, ...},
           msg_flags=0}, 0) = 0 // graceful shutdown for SOCK_SEQPACKET via SCTP_EOF
close(3) = 0

tcpdump before patch (fooling the application):

22:33:36.306142 IP 192.168.1.114.41462 > 192.168.1.115.8888: sctp (1) [INIT] [init tag: 3879023686] [rwnd: 106496] [OS: 10] [MIS: 65535] [init TSN: 3139201684]
22:33:36.316619 IP 192.168.1.115.8888 > 192.168.1.114.41462: sctp (1) [INIT ACK] [init tag: 3345394793] [rwnd: 106496] [OS: 10] [MIS: 10] [init TSN: 3380109591]
22:33:36.317600 IP 192.168.1.114.41462 > 192.168.1.115.8888: sctp (1) [ABORT]

tcpdump after patch:

14:28:58.884116 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [INIT] [init tag: 438593213] [rwnd: 106496] [OS: 10] [MIS: 65535] [init TSN: 3092969729]
14:28:58.888414 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [INIT ACK] [init tag: 381429855] [rwnd: 106496] [OS: 10] [MIS: 10] [init TSN: 2141904492]
14:28:58.888638 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [COOKIE ECHO] , (2) [DATA] (B)(E) [TSN: 3092969729] [...]
14:28:58.893278 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [COOKIE ACK] , (2) [SACK] [cum ack 3092969729] [a_rwnd 106491] [#gap acks 0] [#dup tsns 0]
14:28:58.893591 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [DATA] (B)(E) [TSN: 3092969730] [...]
14:28:59.096963 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SACK] [cum ack 3092969730] [a_rwnd 106496] [#gap acks 0] [#dup tsns 0]
14:28:59.097086 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [DATA] (B)(E) [TSN: 3092969731] [...] , (2) [DATA] (B)(E) [TSN: 3092969732] [...]
14:28:59.103218 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SACK] [cum ack 3092969732] [a_rwnd 106486] [#gap acks 0] [#dup tsns 0]
14:28:59.103330 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [SHUTDOWN]
14:28:59.107793 IP 192.168.1.115.8888 > 192.168.1.114.35846: sctp (1) [SHUTDOWN ACK]
14:28:59.107890 IP 192.168.1.114.35846 > 192.168.1.115.8888: sctp (1) [SHUTDOWN COMPLETE]

Looks like this bug is from the pre-git history museum. ;)

Fixes: 08707d5482df ("lksctp-2_5_31-0_5_1.patch")
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NVlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2061dcd6
  5. 17 1月, 2015 3 次提交
    • J
      genetlink: synchronize socket closing and family removal · ee1c2442
      由 Johannes Berg 提交于 
      In addition to the problem Jeff Layton reported, I looked at the code
and reproduced the same warning by subscribing and removing the genl
family with a socket still open. This is a fairly tricky race which
originates in the fact that generic netlink allows the family to go
away while sockets are still open - unlike regular netlink which has
a module refcount for every open socket so in general this cannot be
triggered.

Trying to resolve this issue by the obvious locking isn't possible as
it will result in deadlocks between unregistration and group unbind
notification (which incidentally lockdep doesn't find due to the home
grown locking in the netlink table.)

To really resolve this, introduce a "closing socket" reference counter
(for generic netlink only, as it's the only affected family) in the
core netlink code and use that in generic netlink to wait for all the
sockets that are being closed at the same time as a generic netlink
family is removed.

This fixes the race that when a socket is closed, it will should call
the unbind, but if the family is removed at the same time the unbind
will not find it, leading to the warning. The real problem though is
that in this case the unbind could actually find a new family that is
registered to have a multicast group with the same ID, and call its
mcast_unbind() leading to confusing.

Also remove the warning since it would still trigger, but is now no
longer a problem.

This also moves the code in af_netlink.c to before unreferencing the
module to avoid having the same problem in the normal non-genl case.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ee1c2442
    • J
      genetlink: disallow subscribing to unknown mcast groups · 5ad63005
      由 Johannes Berg 提交于 
      Jeff Layton reported that he could trigger the multicast unbind warning
in generic netlink using trinity. I originally thought it was a race
condition between unregistering the generic netlink family and closing
the socket, but there's a far simpler explanation: genetlink currently
allows subscribing to groups that don't (yet) exist, and the warning is
triggered when unsubscribing again while the group still doesn't exist.

Originally, I had a warning in the subscribe case and accepted it out of
userspace API concerns, but the warning was of course wrong and removed
later.

However, I now think that allowing userspace to subscribe to groups that
don't exist is wrong and could possibly become a security problem:
Consider a (new) genetlink family implementing a permission check in
the mcast_bind() function similar to the like the audit code does today;
it would be possible to bypass the permission check by guessing the ID
and subscribing to the group it exists. This is only possible in case a
family like that would be dynamically loaded, but it doesn't seem like a
huge stretch, for example wireless may be loaded when you plug in a USB
device.

To avoid this reject such subscription attempts.

If this ends up causing userspace issues we may need to add a workaround
in af_netlink to deny such requests but not return an error.
Reported-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5ad63005
    • J
      genetlink: document parallel_ops · f555f3d7
      由 Johannes Berg 提交于 
      The kernel-doc for the parallel_ops family struct member is
missing, add it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f555f3d7
  7. 16 1月, 2015 16 次提交
  9. 15 1月, 2015 13 次提交
    • A
      can: kvaser_usb: Don't dereference skb after a netif_rx() · a58518cc
      由 Ahmed S. Darwish 提交于 
      We should not touch the packet after a netif_rx: it might
get freed behind our back.
Suggested-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      a58518cc
    • A
      can: kvaser_usb: Don't send a RESET_CHIP for non-existing channels · 5e7e6e0c
      由 Ahmed S. Darwish 提交于 
      Recent Leaf firmware versions (>= 3.1.557) do not allow to send
commands for non-existing channels.  If a command is sent for a
non-existing channel, the firmware crashes.
Reported-by: NChristopher Storah <Christopher.Storah@invetech.com.au>
Signed-off-by: NOlivier Sobrie <olivier@sobrie.be>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      5e7e6e0c
    • A
      can: kvaser_usb: Reset all URB tx contexts upon channel close · 889b77f7
      由 Ahmed S. Darwish 提交于 
      Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in very high frequency (*), closing the CAN channel while
all the transmissions are on (#), opening the device again (@),
then sending a small number of packets would make the driver
enter an almost infinite loop of:

[....]
[15959.853988] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853990] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853991] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853993] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853994] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853995] kvaser_usb 4-3:1.0 can0: cannot find free context
[....]

_dragging the whole system down_ in the process due to the
excessive logging output.

Initially, this has caused random panics in the kernel due to a
buggy error recovery path.  That got fixed in an earlier commit.(%)
This patch aims at solving the root cause. -->

16 tx URBs and contexts are allocated per CAN channel per USB
device. Such URBs are protected by:

a) A simple atomic counter, up to a value of MAX_TX_URBS (16)
b) A flag in each URB context, stating if it's free
c) The fact that ndo_start_xmit calls are themselves protected
   by the networking layers higher above

After grabbing one of the tx URBs, if the driver noticed that all
of them are now taken, it stops the netif transmission queue.
Such queue is worken up again only if an acknowedgment was received
from the firmware on one of our earlier-sent frames.

Meanwhile, upon channel close (#), the driver sends a CMD_STOP_CHIP
to the firmware, effectively closing all further communication.  In
the high traffic case, the atomic counter remains at MAX_TX_URBS,
and all the URB contexts remain marked as active.  While opening
the channel again (@), it cannot send any further frames since no
more free tx URB contexts are available.

Reset all tx URB contexts upon CAN channel close.

(*) 50 parallel instances of `cangen0 -g 0 -ix`
(#) `ifconfig can0 down`
(@) `ifconfig can0 up`
(%) "can: kvaser_usb: Don't free packets when tight on URBs"
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      889b77f7
    • A
      can: kvaser_usb: Don't free packets when tight on URBs · b442723f
      由 Ahmed S. Darwish 提交于 
      Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in high frequency caused seemingly-random panics in the
kernel.

On further inspection, it seems the driver erroneously freed the
to-be-transmitted packet upon getting tight on URBs and returning
NETDEV_TX_BUSY, leading to invalid memory writes and double frees
at a later point in time.

Note:

Finding no more URBs/transmit-contexts and returning NETDEV_TX_BUSY
is a driver bug in and out of itself: it means that our start/stop
queue flow control is broken.

This patch only fixes the (buggy) error handling code; the root
cause shall be fixed in a later commit.
Acked-by: NOlivier Sobrie <olivier@sobrie.be>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      b442723f
    • R
      can: c_can: use regmap_update_bits() to modify RAMINIT register · 47e3485a
      由 Roger Quadros 提交于 
      use of regmap_read() and regmap_write() in c_can_hw_raminit_syscon()
is not safe as the RAMINIT register can be shared between different drivers
at least for TI SoCs.

To make the modification atomic we switch to using regmap_update_bits().

regmap_update_bits() skips writing to the register if it's read content is the
same as what is going to be written. This causes an issue for us when we
need to clear the DONE bit with the initial condition START:0, DONE:1 as
DONE bit must be written with 1 to clear it.

So we defer the clearing of DONE bit to later when we set the START bit.
There we are sure that START bit is changed from 0 to 1 so the write of
1 to already set DONE bit will happen.
Signed-off-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      47e3485a
    • O
      can: m_can: tag current CAN FD controllers as non-ISO · 6cfda7fb
      由 Oliver Hartkopp 提交于 
      During the CAN FD standardization process within the ISO it turned out that
the failure detection capability has to be improved.

The CAN in Automation organization (CiA) defined the already implemented CAN
FD controllers as 'non-ISO' and the upcoming improved CAN FD controllers as
'ISO' compliant. See at http://www.can-cia.com/index.php?id=1937

Finally there will be three types of CAN FD controllers in the future:

1. ISO compliant (fixed)
2. non-ISO compliant (fixed, like the M_CAN IP v3.0.1 in m_can.c)
3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK USB FD)

So the current M_CAN driver for the M_CAN IP v3.0.1 has to expose its non-ISO
implementation by setting the CAN_CTRLMODE_FD_NON_ISO ctrlmode at startup.
As this bit cannot be switched at configuration time CAN_CTRLMODE_FD_NON_ISO
must not be set in ctrlmode_supported of the current M_CAN driver.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      6cfda7fb
    • O
      can: dev: fix crtlmode_supported check · 9b1087aa
      由 Oliver Hartkopp 提交于 
      When changing flags in the CAN drivers ctrlmode the provided new content has to
be checked whether the bits are allowed to be changed. The bits that are to be
changed are given as a bitfield in cm->mask. Therefore checking against
cm->flags is wrong as the content can hold any kind of values.

The iproute2 tool sets the bits in cm->mask and cm->flags depending on the
detected command line options. To be robust against bogus user space
applications additionally sanitize the provided flags with the provided mask.

Cc: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      9b1087aa
    • M
      MAINTAINERS: update linux-can git repositories · 870482a4
      由 Marc Kleine-Budde 提交于 
      The linux-can upstream git repositories are now hosted on kernel.org, update
MAINTAINERS accordingly.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
      870482a4
    • S
      be2net: Allow GRE to work concurrently while a VxLAN tunnel is configured · 16dde0d6
      由 Sriharsha Basavapatna 提交于 
      Other tunnels like GRE break while VxLAN offloads are enabled in Skyhawk-R. To
avoid this, we should restrict offload features on a per-packet basis in such
conditions.
Signed-off-by: NSriharsha Basavapatna <sriharsha.basavapatna@emulex.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      16dde0d6
    • L
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · a6391a92
      由 Linus Torvalds 提交于 
      Pull networking fixes from David Miller:

 1) Don't use uninitialized data in IPVS, from Dan Carpenter.

 2) conntrack race fixes from Pablo Neira Ayuso.

 3) Fix TX hangs with i40e, from Jesse Brandeburg.

 4) Fix budget return from poll calls in dnet and alx, from Eric
    Dumazet.

 5) Fix bugus "if (unlikely(x) < 0)" test in AF_PACKET, from Christoph
    Jaeger.

 6) Fix bug introduced by conversion to list_head in TIPC retransmit
    code, from Jon Paul Maloy.

 7) Don't use GFP_NOIO under spinlock in USB kaweth driver, from Alexey
    Khoroshilov.

 8) Fix bridge build with INET disabled, from Arnd Bergmann.

 9) Fix netlink array overrun for PROBE attributes in openvswitch, from
    Thomas Graf.

10) Don't hold spinlock across synchronize_irq() in tg3 driver, from
    Prashant Sreedharan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
  tg3: Release tp->lock before invoking synchronize_irq()
  tg3: tg3_reset_task() needs to use rtnl_lock to synchronize
  tg3: tg3_timer() should grab tp->lock before checking for tp->irq_sync
  team: avoid possible underflow of count_pending value for notify_peers and mcast_rejoin
  openvswitch: packet messages need their own probe attribtue
  i40e: adds FCoE configure option
  cxgb4vf: Fix queue allocation for 40G adapter
  netdevice: Add missing parentheses in macro
  bridge: only provide proxy ARP when CONFIG_INET is enabled
  neighbour: fix base_reachable_time(_ms) not effective immediatly when changed
  net: fec: fix MDIO bus assignement for dual fec SoC's
  xen-netfront: use different locks for Rx and Tx stats
  drivers: net: cpsw: fix multicast flush in dual emac mode
  cxgb4vf: Initialize mdio_addr before using it
  net: Corrected the comment describing the ndo operations to reflect the actual prototype for couple of operations
  usb/kaweth: use GFP_ATOMIC under spin_lock in usb_start_wait_urb()
  MAINTAINERS: add me as ibmveth maintainer
  tipc: fix bug in broadcast retransmit code
  update ip-sysctl.txt documentation (v2)
  net/at91_ether: prepare and unprepare clock
  ...
      a6391a92
    • D
      Merge branch 'tg3-net' · c637dbce
      由 David S. Miller 提交于 
      Prashant Sreedharan says:

====================
tg3: synchronize_irq() should be called without taking locks

v2: Added Reported-by, Tested-by fields and reference to the thread that
    reported the problem

This series addresses the problem reported by Peter Hurley in mail thread
https://lkml.org/lkml/2015/1/12/1082
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c637dbce
    • P
      tg3: Release tp->lock before invoking synchronize_irq() · 932f19de
      由 Prashant Sreedharan 提交于 
      synchronize_irq() can sleep waiting, for pending IRQ handlers so driver
should release the tp->lock spin lock before invoking synchronize_irq()
Reported-by: NPeter Hurley <peter@hurleysoftware.com>
Tested-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NPrashant Sreedharan <prashant@broadcom.com>
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      932f19de
    • P
      tg3: tg3_reset_task() needs to use rtnl_lock to synchronize · db84bf43
      由 Prashant Sreedharan 提交于 
      Currently tg3_reset_task() uses only tp->lock for synchronizing with code
paths like tg3_open() etc. But since tp->lock is released before doing
synchronize_irq(), rtnl_lock should be taken in tg3_reset_task() to
synchronize it with other code paths.
Reported-by: NPeter Hurley <peter@hurleysoftware.com>
Tested-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NPrashant Sreedharan <prashant@broadcom.com>
Signed-off-by: NMichael Chan <mchan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      db84bf43