Commit Graph

33219 Commits

Author SHA1 Message Date
Linus Torvalds
79eb238c76 TTY / Serial driver update for 3.17-rc1
Here's the big tty / serial driver update for 3.17-rc1.
 
 Nothing major, just a number of fixes and new features for different
 serial drivers, and some more tty core fixes and documentation of the
 tty locks.
 
 All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iEYEABECAAYFAlPf2C4ACgkQMUfUDdst+yllVgCgtZl/Mcr/LlxPgjsg2C1AE7nX
 YJ4An3o4N112bkdGqhZ7RjAE6K/8YILx
 =rPhE
 -----END PGP SIGNATURE-----

Merge tag 'tty-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver update from Greg KH:
 "Here's the big tty / serial driver update for 3.17-rc1.

  Nothing major, just a number of fixes and new features for different
  serial drivers, and some more tty core fixes and documentation of the
  tty locks.

  All of these have been in linux-next for a while"

* tag 'tty-3.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (82 commits)
  tty/n_gsm.c: fix a memory leak in gsmld_open
  pch_uart: don't hardcode PCI slot to get DMA device
  tty: n_gsm, use setup_timer
  Revert "ARC: [arcfpga] stdout-path now suffices for earlycon/console"
  serial: sc16is7xx: Correct initialization of s->clk
  serial: 8250_dw: Add support for deferred probing
  serial: 8250_dw: Add optional reset control support
  serial: st-asc: Fix overflow in baudrate calculation
  serial: st-asc: Don't call BUG in asc_console_setup()
  tty: serial: msm: Make of_device_id array const
  tty/n_gsm.c: get gsm->num after gsm_activate_mux
  serial/core: Fix too big allocation for attribute member
  drivers/tty/serial: use correct type for dma_map/unmap
  serial: altera_jtaguart: Fix putchar function passed to uart_console_write()
  serial/uart/8250: Add tunable RX interrupt trigger I/F of FIFO buffers
  Serial: allow port drivers to have a default attribute group
  tty: kgdb_nmi: Automatically manage tty enable
  serial: altera_jtaguart: Adpot uart_console_write()
  serial: samsung: improve code clarity by defining a variable
  serial: samsung: correct the case and default order in switch
  ...
2014-08-04 18:51:19 -07:00
Linus Torvalds
98959948a7 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - Move the nohz kick code out of the scheduler tick to a dedicated IPI,
   from Frederic Weisbecker.

  This necessiated quite some background infrastructure rework,
  including:

   * Clean up some irq-work internals
   * Implement remote irq-work
   * Implement nohz kick on top of remote irq-work
   * Move full dynticks timer enqueue notification to new kick
   * Move multi-task notification to new kick
   * Remove unecessary barriers on multi-task notification

 - Remove proliferation of wait_on_bit() action functions and allow
   wait_on_bit_action() functions to support a timeout.  (Neil Brown)

 - Another round of sched/numa improvements, cleanups and fixes.  (Rik
   van Riel)

 - Implement fast idling of CPUs when the system is partially loaded,
   for better scalability.  (Tim Chen)

 - Restructure and fix the CPU hotplug handling code that may leave
   cfs_rq and rt_rq's throttled when tasks are migrated away from a dead
   cpu.  (Kirill Tkhai)

 - Robustify the sched topology setup code.  (Peterz Zijlstra)

 - Improve sched_feat() handling wrt.  static_keys (Jason Baron)

 - Misc fixes.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  sched/fair: Fix 'make xmldocs' warning caused by missing description
  sched: Use macro for magic number of -1 for setparam
  sched: Robustify topology setup
  sched: Fix sched_setparam() policy == -1 logic
  sched: Allow wait_on_bit_action() functions to support a timeout
  sched: Remove proliferation of wait_on_bit() action functions
  sched/numa: Revert "Use effective_load() to balance NUMA loads"
  sched: Fix static_key race with sched_feat()
  sched: Remove extra static_key*() function indirection
  sched/rt: Fix replenish_dl_entity() comments to match the current upstream code
  sched: Transform resched_task() into resched_curr()
  sched/deadline: Kill task_struct->pi_top_task
  sched: Rework check_for_tasks()
  sched/rt: Enqueue just unthrottled rt_rq back on the stack in __disable_runtime()
  sched/fair: Disable runtime_enabled on dying rq
  sched/numa: Change scan period code to match intent
  sched/numa: Rework best node setting in task_numa_migrate()
  sched/numa: Examine a task move when examining a task swap
  sched/numa: Simplify task_numa_compare()
  sched/numa: Use effective_load() to balance NUMA loads
  ...
2014-08-04 16:23:30 -07:00
Linus Torvalds
47dfe4037e Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup changes from Tejun Heo:
 "Mostly changes to get the v2 interface ready.  The core features are
  mostly ready now and I think it's reasonable to expect to drop the
  devel mask in one or two devel cycles at least for a subset of
  controllers.

   - cgroup added a controller dependency mechanism so that block cgroup
     can depend on memory cgroup.  This will be used to finally support
     IO provisioning on the writeback traffic, which is currently being
     implemented.

   - The v2 interface now uses a separate table so that the interface
     files for the new interface are explicitly declared in one place.
     Each controller will explicitly review and add the files for the
     new interface.

   - cpuset is getting ready for the hierarchical behavior which is in
     the similar style with other controllers so that an ancestor's
     configuration change doesn't change the descendants' configurations
     irreversibly and processes aren't silently migrated when a CPU or
     node goes down.

  All the changes are to the new interface and no behavior changed for
  the multiple hierarchies"

* 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (29 commits)
  cpuset: fix the WARN_ON() in update_nodemasks_hier()
  cgroup: initialize cgrp_dfl_root_inhibit_ss_mask from !->dfl_files test
  cgroup: make CFTYPE_ONLY_ON_DFL and CFTYPE_NO_ internal to cgroup core
  cgroup: distinguish the default and legacy hierarchies when handling cftypes
  cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes()
  cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes
  cgroup: split cgroup_base_files[] into cgroup_{dfl|legacy}_base_files[]
  cpuset: export effective masks to userspace
  cpuset: allow writing offlined masks to cpuset.cpus/mems
  cpuset: enable onlined cpu/node in effective masks
  cpuset: refactor cpuset_hotplug_update_tasks()
  cpuset: make cs->{cpus, mems}_allowed as user-configured masks
  cpuset: apply cs->effective_{cpus,mems}
  cpuset: initialize top_cpuset's configured masks at mount
  cpuset: use effective cpumask to build sched domains
  cpuset: inherit ancestor's masks if effective_{cpus, mems} becomes empty
  cpuset: update cs->effective_{cpus, mems} when config changes
  cpuset: update cpuset->effective_{cpus,mems} at hotplug
  cpuset: add cs->effective_cpus and cs->effective_mems
  cgroup: clean up sane_behavior handling
  ...
2014-08-04 10:11:28 -07:00
Andrey Ryabinin
40eea803c6 net: sendmsg: fix NULL pointer dereference
Sasha's report:
	> While fuzzing with trinity inside a KVM tools guest running the latest -next
	> kernel with the KASAN patchset, I've stumbled on the following spew:
	>
	> [ 4448.949424] ==================================================================
	> [ 4448.951737] AddressSanitizer: user-memory-access on address 0
	> [ 4448.952988] Read of size 2 by thread T19638:
	> [ 4448.954510] CPU: 28 PID: 19638 Comm: trinity-c76 Not tainted 3.16.0-rc4-next-20140711-sasha-00046-g07d3099-dirty #813
	> [ 4448.956823]  ffff88046d86ca40 0000000000000000 ffff880082f37e78 ffff880082f37a40
	> [ 4448.958233]  ffffffffb6e47068 ffff880082f37a68 ffff880082f37a58 ffffffffb242708d
	> [ 4448.959552]  0000000000000000 ffff880082f37a88 ffffffffb24255b1 0000000000000000
	> [ 4448.961266] Call Trace:
	> [ 4448.963158] dump_stack (lib/dump_stack.c:52)
	> [ 4448.964244] kasan_report_user_access (mm/kasan/report.c:184)
	> [ 4448.965507] __asan_load2 (mm/kasan/kasan.c:352)
	> [ 4448.966482] ? netlink_sendmsg (net/netlink/af_netlink.c:2339)
	> [ 4448.967541] netlink_sendmsg (net/netlink/af_netlink.c:2339)
	> [ 4448.968537] ? get_parent_ip (kernel/sched/core.c:2555)
	> [ 4448.970103] sock_sendmsg (net/socket.c:654)
	> [ 4448.971584] ? might_fault (mm/memory.c:3741)
	> [ 4448.972526] ? might_fault (./arch/x86/include/asm/current.h:14 mm/memory.c:3740)
	> [ 4448.973596] ? verify_iovec (net/core/iovec.c:64)
	> [ 4448.974522] ___sys_sendmsg (net/socket.c:2096)
	> [ 4448.975797] ? put_lock_stats.isra.13 (./arch/x86/include/asm/preempt.h:98 kernel/locking/lockdep.c:254)
	> [ 4448.977030] ? lock_release_holdtime (kernel/locking/lockdep.c:273)
	> [ 4448.978197] ? lock_release_non_nested (kernel/locking/lockdep.c:3434 (discriminator 1))
	> [ 4448.979346] ? check_chain_key (kernel/locking/lockdep.c:2188)
	> [ 4448.980535] __sys_sendmmsg (net/socket.c:2181)
	> [ 4448.981592] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2600)
	> [ 4448.982773] ? trace_hardirqs_on (kernel/locking/lockdep.c:2607)
	> [ 4448.984458] ? syscall_trace_enter (arch/x86/kernel/ptrace.c:1500 (discriminator 2))
	> [ 4448.985621] ? trace_hardirqs_on_caller (kernel/locking/lockdep.c:2600)
	> [ 4448.986754] SyS_sendmmsg (net/socket.c:2201)
	> [ 4448.987708] tracesys (arch/x86/kernel/entry_64.S:542)
	> [ 4448.988929] ==================================================================

This reports means that we've come to netlink_sendmsg() with msg->msg_name == NULL and msg->msg_namelen > 0.

After this report there was no usual "Unable to handle kernel NULL pointer dereference"
and this gave me a clue that address 0 is mapped and contains valid socket address structure in it.

This bug was introduced in f3d3342602
(net: rework recvmsg handler msg_name and msg_namelen logic).
Commit message states that:
	"Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
	 non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
	 affect sendto as it would bail out earlier while trying to copy-in the
	 address."
But in fact this affects sendto when address 0 is mapped and contains
socket address structure in it. In such case copy-in address will succeed,
verify_iovec() function will successfully exit with msg->msg_namelen > 0
and msg->msg_name == NULL.

This patch fixes it by setting msg_namelen to 0 if msg_name == NULL.

Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: <stable@vger.kernel.org>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-29 12:20:22 -07:00
Eric Dumazet
04ca6973f7 ip: make IP identifiers less predictable
In "Counting Packets Sent Between Arbitrary Internet Hosts", Jeffrey and
Jedidiah describe ways exploiting linux IP identifier generation to
infer whether two machines are exchanging packets.

With commit 73f156a6e8 ("inetpeer: get rid of ip_id_count"), we
changed IP id generation, but this does not really prevent this
side-channel technique.

This patch adds a random amount of perturbation so that IP identifiers
for a given destination [1] are no longer monotonically increasing after
an idle period.

Note that prandom_u32_max(1) returns 0, so if generator is used at most
once per jiffy, this patch inserts no hole in the ID suite and do not
increase collision probability.

This is jiffies based, so in the worst case (HZ=1000), the id can
rollover after ~65 seconds of idle time, which should be fine.

We also change the hash used in __ip_select_ident() to not only hash
on daddr, but also saddr and protocol, so that ICMP probes can not be
used to infer information for other protocols.

For IPv6, adds saddr into the hash as well, but not nexthdr.

If I ping the patched target, we can see ID are now hard to predict.

21:57:11.008086 IP (...)
    A > target: ICMP echo request, seq 1, length 64
21:57:11.010752 IP (... id 2081 ...)
    target > A: ICMP echo reply, seq 1, length 64

21:57:12.013133 IP (...)
    A > target: ICMP echo request, seq 2, length 64
21:57:12.015737 IP (... id 3039 ...)
    target > A: ICMP echo reply, seq 2, length 64

21:57:13.016580 IP (...)
    A > target: ICMP echo request, seq 3, length 64
21:57:13.019251 IP (... id 3437 ...)
    target > A: ICMP echo reply, seq 3, length 64

[1] TCP sessions uses a per flow ID generator not changed by this patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jeffrey Knockel <jeffk@cs.unm.edu>
Reported-by: Jedidiah R. Crandall <crandall@cs.unm.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Hannes Frederic Sowa <hannes@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-28 18:46:34 -07:00
Jun Zhao
545469f7a5 neighbour : fix ndm_type type error issue
ndm_type means L3 address type, in neighbour proxy and vxlan, it's RTN_UNICAST.
NDA_DST is for netlink TLV type, hence it's not right value in this context.

Signed-off-by: Jun Zhao <mypopydev@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-28 17:52:17 -07:00
Ingo Molnar
ca5bc6cd5d Merge branch 'sched/urgent' into sched/core, to merge fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-28 10:03:00 +02:00
David S. Miller
e62f77579c Merge tag 'master-2014-07-23' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
John W. Linville says:

====================
pull request: wireless 2014-07-24

Please pull this batch of fixes intended for the 3.16 stream...

For the mac80211 fixes, Johannes says:

"I have two fixes: one for tracing that fixes a long-standing NULL
pointer dereference, and one for a mac80211 issue that causes iwlmvm to
send invalid frames during authentication/association."

and,

"One more fix - for a bug in the newly introduced code that obtains rate
control information for stations."

For the iwlwifi fixes, Emmanuel says:

"It includes a merge damage fix. This region has been changed in -next
and -fixes quite a few times and apparently, I failed to handle it
properly, so here the fix.  Along with that I have a fix from Eliad
to properly handle overlapping BSS in AP mode."

On top of that, Felix provides and ath9k fix for Tx stalls that happen
after an aggregation session failure.

Please let me know if there are problems!  There are some changes
here that will cause merge conflicts in -next.  Once you merge this
I can pull it into wireless-next and resolve those issues.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-24 23:22:15 -07:00
David S. Miller
29be618076 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Via Simon Horman, I received the following one-liner for your net tree:

1) Fix crash when exiting from netns that uses IPVS and conntrack,
   from Julian Anastasov via Simon Horman.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-24 18:00:05 -07:00
David S. Miller
11f1fb3459 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2014-07-23

Just two fixes this time, both are stable candidates.

1) Fix the dst_entry refcount on socket policy usage.

2) Fix a wrong SPI check that prevents AH SAs from getting
   installed, dependent on the SPI. From Tobias Brunner.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-23 21:56:36 -07:00
John W. Linville
3b8de07492 Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 2014-07-23 13:01:14 -04:00
Daniel Borkmann
1be9a950c6 net: sctp: inherit auth_capable on INIT collisions
Jason reported an oops caused by SCTP on his ARM machine with
SCTP authentication enabled:

Internal error: Oops: 17 [#1] ARM
CPU: 0 PID: 104 Comm: sctp-test Not tainted 3.13.0-68744-g3632f30c9b20-dirty #1
task: c6eefa40 ti: c6f52000 task.ti: c6f52000
PC is at sctp_auth_calculate_hmac+0xc4/0x10c
LR is at sg_init_table+0x20/0x38
pc : [<c024bb80>]    lr : [<c00f32dc>]    psr: 40000013
sp : c6f538e8  ip : 00000000  fp : c6f53924
r10: c6f50d80  r9 : 00000000  r8 : 00010000
r7 : 00000000  r6 : c7be4000  r5 : 00000000  r4 : c6f56254
r3 : c00c8170  r2 : 00000001  r1 : 00000008  r0 : c6f1e660
Flags: nZcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 0005397f  Table: 06f28000  DAC: 00000015
Process sctp-test (pid: 104, stack limit = 0xc6f521c0)
Stack: (0xc6f538e8 to 0xc6f54000)
[...]
Backtrace:
[<c024babc>] (sctp_auth_calculate_hmac+0x0/0x10c) from [<c0249af8>] (sctp_packet_transmit+0x33c/0x5c8)
[<c02497bc>] (sctp_packet_transmit+0x0/0x5c8) from [<c023e96c>] (sctp_outq_flush+0x7fc/0x844)
[<c023e170>] (sctp_outq_flush+0x0/0x844) from [<c023ef78>] (sctp_outq_uncork+0x24/0x28)
[<c023ef54>] (sctp_outq_uncork+0x0/0x28) from [<c0234364>] (sctp_side_effects+0x1134/0x1220)
[<c0233230>] (sctp_side_effects+0x0/0x1220) from [<c02330b0>] (sctp_do_sm+0xac/0xd4)
[<c0233004>] (sctp_do_sm+0x0/0xd4) from [<c023675c>] (sctp_assoc_bh_rcv+0x118/0x160)
[<c0236644>] (sctp_assoc_bh_rcv+0x0/0x160) from [<c023d5bc>] (sctp_inq_push+0x6c/0x74)
[<c023d550>] (sctp_inq_push+0x0/0x74) from [<c024a6b0>] (sctp_rcv+0x7d8/0x888)

While we already had various kind of bugs in that area
ec0223ec48 ("net: sctp: fix sctp_sf_do_5_1D_ce to verify if
we/peer is AUTH capable") and b14878ccb7 ("net: sctp: cache
auth_enable per endpoint"), this one is a bit of a different
kind.

Giving a bit more background on why SCTP authentication is
needed can be found in RFC4895:

  SCTP uses 32-bit verification tags to protect itself against
  blind attackers. These values are not changed during the
  lifetime of an SCTP association.

  Looking at new SCTP extensions, there is the need to have a
  method of proving that an SCTP chunk(s) was really sent by
  the original peer that started the association and not by a
  malicious attacker.

To cause this bug, we're triggering an INIT collision between
peers; normal SCTP handshake where both sides intent to
authenticate packets contains RANDOM; CHUNKS; HMAC-ALGO
parameters that are being negotiated among peers:

  ---------- INIT[RANDOM; CHUNKS; HMAC-ALGO] ---------->
  <------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] ---------
  -------------------- COOKIE-ECHO -------------------->
  <-------------------- COOKIE-ACK ---------------------

RFC4895 says that each endpoint therefore knows its own random
number and the peer's random number *after* the association
has been established. The local and peer's random number along
with the shared key are then part of the secret used for
calculating the HMAC in the AUTH chunk.

Now, in our scenario, we have 2 threads with 1 non-blocking
SEQ_PACKET socket each, setting up common shared SCTP_AUTH_KEY
and SCTP_AUTH_ACTIVE_KEY properly, and each of them calling
sctp_bindx(3), listen(2) and connect(2) against each other,
thus the handshake looks similar to this, e.g.:

  ---------- INIT[RANDOM; CHUNKS; HMAC-ALGO] ---------->
  <------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] ---------
  <--------- INIT[RANDOM; CHUNKS; HMAC-ALGO] -----------
  -------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] -------->
  ...

Since such collisions can also happen with verification tags,
the RFC4895 for AUTH rather vaguely says under section 6.1:

  In case of INIT collision, the rules governing the handling
  of this Random Number follow the same pattern as those for
  the Verification Tag, as explained in Section 5.2.4 of
  RFC 2960 [5]. Therefore, each endpoint knows its own Random
  Number and the peer's Random Number after the association
  has been established.

In RFC2960, section 5.2.4, we're eventually hitting Action B:

  B) In this case, both sides may be attempting to start an
     association at about the same time but the peer endpoint
     started its INIT after responding to the local endpoint's
     INIT. Thus it may have picked a new Verification Tag not
     being aware of the previous Tag it had sent this endpoint.
     The endpoint should stay in or enter the ESTABLISHED
     state but it MUST update its peer's Verification Tag from
     the State Cookie, stop any init or cookie timers that may
     running and send a COOKIE ACK.

In other words, the handling of the Random parameter is the
same as behavior for the Verification Tag as described in
Action B of section 5.2.4.

Looking at the code, we exactly hit the sctp_sf_do_dupcook_b()
case which triggers an SCTP_CMD_UPDATE_ASSOC command to the
side effect interpreter, and in fact it properly copies over
peer_{random, hmacs, chunks} parameters from the newly created
association to update the existing one.

Also, the old asoc_shared_key is being released and based on
the new params, sctp_auth_asoc_init_active_key() updated.
However, the issue observed in this case is that the previous
asoc->peer.auth_capable was 0, and has *not* been updated, so
that instead of creating a new secret, we're doing an early
return from the function sctp_auth_asoc_init_active_key()
leaving asoc->asoc_shared_key as NULL. However, we now have to
authenticate chunks from the updated chunk list (e.g. COOKIE-ACK).

That in fact causes the server side when responding with ...

  <------------------ AUTH; COOKIE-ACK -----------------

... to trigger a NULL pointer dereference, since in
sctp_packet_transmit(), it discovers that an AUTH chunk is
being queued for xmit, and thus it calls sctp_auth_calculate_hmac().

Since the asoc->active_key_id is still inherited from the
endpoint, and the same as encoded into the chunk, it uses
asoc->asoc_shared_key, which is still NULL, as an asoc_key
and dereferences it in ...

  crypto_hash_setkey(desc.tfm, &asoc_key->data[0], asoc_key->len)

... causing an oops. All this happens because sctp_make_cookie_ack()
called with the *new* association has the peer.auth_capable=1
and therefore marks the chunk with auth=1 after checking
sctp_auth_send_cid(), but it is *actually* sent later on over
the then *updated* association's transport that didn't initialize
its shared key due to peer.auth_capable=0. Since control chunks
in that case are not sent by the temporary association which
are scheduled for deletion, they are issued for xmit via
SCTP_CMD_REPLY in the interpreter with the context of the
*updated* association. peer.auth_capable was 0 in the updated
association (which went from COOKIE_WAIT into ESTABLISHED state),
since all previous processing that performed sctp_process_init()
was being done on temporary associations, that we eventually
throw away each time.

The correct fix is to update to the new peer.auth_capable
value as well in the collision case via sctp_assoc_update(),
so that in case the collision migrated from 0 -> 1,
sctp_auth_asoc_init_active_key() can properly recalculate
the secret. This therefore fixes the observed server panic.

Fixes: 730fc3d05c ("[SCTP]: Implete SCTP-AUTH parameter processing")
Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-22 19:56:58 -07:00
Felix Fietkau
fa8f136fe9 mac80211: fix crash on getting sta info with uninitialized rate control
If the expected throughput is queried before rate control has been
initialized, the minstrel op for it will crash while trying to access
the rate table.
Check for WLAN_STA_RATE_CONTROL before attempting to use the rate
control op.

Reported-by: Jean-Pierre Tosoni <jp.tosoni@acksys.fr>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-07-22 22:17:17 +02:00
David S. Miller
850717ef00 Included fixes:
- recognise and drop Bridge Loop Avoidance packets even if
   they are encapsulated in the 802.1q header multiple times.
   Forwarding them into the mesh creates issues on other
   nodes.
 - properly handle VLAN private objects in order to avoid race
   conditions upon fast VLAN deletion-addition. Such conditions
   create an unrecoverable inconsistency in the TT database of
   the nodes.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJTzMYfAAoJEJgn97Bh2u9eKLIP+wWwqvRe5hFleA7Xd7vHS769
 20TrhDPZrQAcaK8dg8/VpqUZ4oGAi0WHhbhAdur1Vj3Ie5DDsqqu45lK9a/o+PAe
 avWafxcPcK5LLoLbDKNxX98n6BN3aNFIp7rUy4CDO7Beix/PfQUYGbZ01IEueNlX
 tvKz1oO7r3SvWFELltSU7bndU+0NoZRon5qXSaxnlYHMXcsJEJAKRPE9eLdwXUaF
 9h0oIKkPVQt8YFn0w1zZRePSPWGQSAb20exgRGwPxI23xs7ui1i+s5Od9aSt8FcR
 e6eNuMDsuHVeAmW+nsxF3WAyYGIGyaTb9sSkwrToXZge7BRFRfphKN1WHD1bp6A5
 a0Lu3wkzCJbrS3LZkjt99jh+0XAaaoWkAt4Lu4+VUcMYtfITHHHN4kfmzoPE7Z8y
 Qq64KL/ry6v2lqGk2+9G5/oHXMAYAyed+TPk/HSn5O0CS+zXxXFvrvbYyQyFg99X
 BcuOD6dGLbfaPQh9XuCE9jJ2D5QHnkAXj2FlK5oFd7y6ASdLltratTYNKJ4T7cVR
 +cyBkZ6cI3Ehzq1jrR8/9qqAal+a/jdzne6J7DPnWksDWxnTylANuWecVkETkpcL
 mUp6Zv9SYISqQSPtrbE7xu1XW/ICoajc+6H0eEOFhKU+JEqKjxwSE2QoKvzxeC8Y
 OHIbq99fItGwH7Vuldkg
 =RdJM
 -----END PGP SIGNATURE-----

Merge tag 'batman-adv-fix-for-davem' of git://git.open-mesh.org/linux-merge

Antonio Quartulli says:

====================
pull request [net]: batman-adv 20140721

here you have two fixes that we have been testing for quite some time
(this is why they arrived a bit late in the rc cycle).

Patch 1) ensures that BLA packets get dropped and not forwarded to the
mesh even if they reach batman-adv within QinQ frames. Forwarding them
into the mesh means messing up with the TT database of other nodes which
can generate all kind of unexpected behaviours during route computation.

Patch 2) avoids a couple of race conditions triggered upon fast VLAN
deletion-addition. Such race conditions are pretty dangerous because
they not only create inconsistencies in the TT database of the nodes
in the network, but such scenario is also unrecoverable (unless
nodes are rebooted).
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21 20:19:09 -07:00
Eric Dumazet
10ec9472f0 ipv4: fix buffer overflow in ip_options_compile()
There is a benign buffer overflow in ip_options_compile spotted by
AddressSanitizer[1] :

Its benign because we always can access one extra byte in skb->head
(because header is followed by struct skb_shared_info), and in this case
this byte is not even used.

[28504.910798] ==================================================================
[28504.912046] AddressSanitizer: heap-buffer-overflow in ip_options_compile
[28504.913170] Read of size 1 by thread T15843:
[28504.914026]  [<ffffffff81802f91>] ip_options_compile+0x121/0x9c0
[28504.915394]  [<ffffffff81804a0d>] ip_options_get_from_user+0xad/0x120
[28504.916843]  [<ffffffff8180dedf>] do_ip_setsockopt.isra.15+0x8df/0x1630
[28504.918175]  [<ffffffff8180ec60>] ip_setsockopt+0x30/0xa0
[28504.919490]  [<ffffffff8181e59b>] tcp_setsockopt+0x5b/0x90
[28504.920835]  [<ffffffff8177462f>] sock_common_setsockopt+0x5f/0x70
[28504.922208]  [<ffffffff817729c2>] SyS_setsockopt+0xa2/0x140
[28504.923459]  [<ffffffff818cfb69>] system_call_fastpath+0x16/0x1b
[28504.924722]
[28504.925106] Allocated by thread T15843:
[28504.925815]  [<ffffffff81804995>] ip_options_get_from_user+0x35/0x120
[28504.926884]  [<ffffffff8180dedf>] do_ip_setsockopt.isra.15+0x8df/0x1630
[28504.927975]  [<ffffffff8180ec60>] ip_setsockopt+0x30/0xa0
[28504.929175]  [<ffffffff8181e59b>] tcp_setsockopt+0x5b/0x90
[28504.930400]  [<ffffffff8177462f>] sock_common_setsockopt+0x5f/0x70
[28504.931677]  [<ffffffff817729c2>] SyS_setsockopt+0xa2/0x140
[28504.932851]  [<ffffffff818cfb69>] system_call_fastpath+0x16/0x1b
[28504.934018]
[28504.934377] The buggy address ffff880026382828 is located 0 bytes to the right
[28504.934377]  of 40-byte region [ffff880026382800, ffff880026382828)
[28504.937144]
[28504.937474] Memory state around the buggy address:
[28504.938430]  ffff880026382300: ........ rrrrrrrr rrrrrrrr rrrrrrrr
[28504.939884]  ffff880026382400: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28504.941294]  ffff880026382500: .....rrr rrrrrrrr rrrrrrrr rrrrrrrr
[28504.942504]  ffff880026382600: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28504.943483]  ffff880026382700: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28504.944511] >ffff880026382800: .....rrr rrrrrrrr rrrrrrrr rrrrrrrr
[28504.945573]                         ^
[28504.946277]  ffff880026382900: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28505.094949]  ffff880026382a00: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28505.096114]  ffff880026382b00: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28505.097116]  ffff880026382c00: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28505.098472]  ffff880026382d00: ffffffff rrrrrrrr rrrrrrrr rrrrrrrr
[28505.099804] Legend:
[28505.100269]  f - 8 freed bytes
[28505.100884]  r - 8 redzone bytes
[28505.101649]  . - 8 allocated bytes
[28505.102406]  x=1..7 - x allocated bytes + (8-x) redzone bytes
[28505.103637] ==================================================================

[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21 20:16:26 -07:00
Antonio Quartulli
35df3b298f batman-adv: fix TT VLAN inconsistency on VLAN re-add
When a VLAN interface (on top of batX) is removed and
re-added within a short timeframe TT does not have enough
time to properly cleanup. This creates an internal TT state
mismatch as the newly created softif_vlan will be
initialized from scratch with a TT client count of zero
(even if TT entries for this VLAN still exist). The
resulting TT messages are bogus due to the counter / tt
client listing mismatch, thus creating inconsistencies on
every node in the network

To fix this issue destroy_vlan() has to not free the VLAN
object immediately but it has to be kept alive until all the
TT entries for this VLAN have been removed. destroy_vlan()
still removes the sysfs folder so that the user has the
feeling that everything went fine.

If the same VLAN is re-added before the old object is free'd,
then the latter is resurrected and re-used.

Implement such behaviour by increasing the reference counter
of a softif_vlan object every time a new local TT entry for
such VLAN is created and remove the object from the list
only when all the TT entries have been destroyed.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
2014-07-21 09:49:30 +02:00
Simon Wunderlich
d46b6bfa76 batman-adv: drop QinQ claim frames in bridge loop avoidance
Since bridge loop avoidance only supports untagged or simple 802.1q
tagged VLAN claim frames, claim frames with stacked VLAN headers (QinQ)
should be detected and dropped. Transporting the over the mesh may cause
problems on the receivers, or create bogus entries in the local tt
tables.

Reported-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Simon Wunderlich <simon@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2014-07-21 09:05:31 +02:00
Ben Hutchings
640d7efe4c dns_resolver: Null-terminate the right string
*_result[len] is parsed as *(_result[len]) which is not at all what we
want to touch here.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 84a7c0b1db ("dns_resolver: assure that dns_query() result is null-terminated")
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20 22:33:32 -07:00
Cong Wang
7801db8aec net_sched: avoid generating same handle for u32 filters
When kernel generates a handle for a u32 filter, it tries to start
from the max in the bucket. So when we have a filter with the max (fff)
handle, it will cause kernel always generates the same handle for new
filters. This can be shown by the following command:

	tc qdisc add dev eth0 ingress
	tc filter add dev eth0 parent ffff: protocol ip pref 770 handle 800::fff u32 match ip protocol 1 0xff
	tc filter add dev eth0 parent ffff: protocol ip pref 770 u32 match ip protocol 1 0xff
	...

we will get some u32 filters with same handle:

 # tc filter show dev eth0 parent ffff:
filter protocol ip pref 770 u32
filter protocol ip pref 770 u32 fh 800: ht divisor 1
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8
filter protocol ip pref 770 u32 fh 800::fff order 4095 key ht 800 bkt 0
  match 00010000/00ff0000 at 8

handles should be unique. This patch fixes it by looking up a bitmap,
so that can guarantee the handle is as unique as possible. For compatibility,
we still start from 0x800.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-20 20:49:17 -07:00
John W. Linville
7fc9427222 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 2014-07-18 12:55:45 -04:00
Eliad Peller
8c26d45839 cfg80211: fix mic_failure tracing
tsc can be NULL (mac80211 currently always passes NULL),
resulting in NULL-dereference. check before copying it.

Cc: stable@vger.kernel.org
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-07-18 09:53:56 +02:00
David S. Miller
38a4dfcf80 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/nf_tables fixes

The following patchset contains nf_tables fixes, they are:

1) Fix wrong transaction handling when the table flags are not
   modified.

2) Fix missing rcu read_lock section in the netlink dump path, which
   is not protected by the nfnl_lock.

3) Set NLM_F_DUMP_INTR in the netlink dump path to indicate
   interferences with updates.

4) Fix 64 bits chain counters when they are retrieved from a 32 bits
   arch, from Eric Dumazet.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 15:27:16 -07:00
Jerry Chu
c3caf1192f net-gre-gro: Fix a bug that breaks the forwarding path
Fixed a bug that was introduced by my GRE-GRO patch
(bf5a755f5e net-gre-gro: Add GRE
support to the GRO stack) that breaks the forwarding path
because various GSO related fields were not set. The bug will
cause on the egress path either the GSO code to fail, or a
GRE-TSO capable (NETIF_F_GSO_GRE) NICs to choke. The following
fix has been tested for both cases.

Signed-off-by: H.K. Jerry Chu <hkchu@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 14:45:26 -07:00
NeilBrown
c1221321b7 sched: Allow wait_on_bit_action() functions to support a timeout
It is currently not possible for various wait_on_bit functions
to implement a timeout.

While the "action" function that is called to do the waiting
could certainly use schedule_timeout(), there is no way to carry
forward the remaining timeout after a false wake-up.
As false-wakeups a clearly possible at least due to possible
hash collisions in bit_waitqueue(), this is a real problem.

The 'action' function is currently passed a pointer to the word
containing the bit being waited on.  No current action functions
use this pointer.  So changing it to something else will be a
little noisy but will have no immediate effect.

This patch changes the 'action' function to take a pointer to
the "struct wait_bit_key", which contains a pointer to the word
containing the bit so nothing is really lost.

It also adds a 'private' field to "struct wait_bit_key", which
is initialized to zero.

An action function can now implement a timeout with something
like

static int timed_out_waiter(struct wait_bit_key *key)
{
	unsigned long waited;
	if (key->private == 0) {
		key->private = jiffies;
		if (key->private == 0)
			key->private -= 1;
	}
	waited = jiffies - key->private;
	if (waited > 10 * HZ)
		return -EAGAIN;
	schedule_timeout(waited - 10 * HZ);
	return 0;
}

If any other need for context in a waiter were found it would be
easy to use ->private for some other purpose, or even extend
"struct wait_bit_key".

My particular need is to support timeouts in nfs_release_page()
to avoid deadlocks with loopback mounted NFS.

While wait_on_bit_timeout() would be a cleaner interface, it
will not meet my need.  I need the timeout to be sensitive to
the state of the connection with the server, which could change.
 So I need to use an 'action' interface.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051604.28027.41257.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 15:10:41 +02:00
NeilBrown
743162013d sched: Remove proliferation of wait_on_bit() action functions
The current "wait_on_bit" interface requires an 'action'
function to be provided which does the actual waiting.
There are over 20 such functions, many of them identical.
Most cases can be satisfied by one of just two functions, one
which uses io_schedule() and one which just uses schedule().

So:
 Rename wait_on_bit and        wait_on_bit_lock to
        wait_on_bit_action and wait_on_bit_lock_action
 to make it explicit that they need an action function.

 Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io
 which are *not* given an action function but implicitly use
 a standard one.
 The decision to error-out if a signal is pending is now made
 based on the 'mode' argument rather than being encoded in the action
 function.

 All instances of the old wait_on_bit and wait_on_bit_lock which
 can use the new version have been changed accordingly and their
 action functions have been discarded.
 wait_on_bit{_lock} does not return any specific error code in the
 event of a signal so the caller must check for non-zero and
 interpolate their own error code as appropriate.

The wait_on_bit() call in __fscache_wait_on_invalidate() was
ambiguous as it specified TASK_UNINTERRUPTIBLE but used
fscache_wait_bit_interruptible as an action function.
David Howells confirms this should be uniformly
"uninterruptible"

The main remaining user of wait_on_bit{,_lock}_action is NFS
which needs to use a freezer-aware schedule() call.

A comment in fs/gfs2/glock.c notes that having multiple 'action'
functions is useful as they display differently in the 'wchan'
field of 'ps'. (and /proc/$PID/wchan).
As the new bit_wait{,_io} functions are tagged "__sched", they
will not show up at all, but something higher in the stack.  So
the distinction will still be visible, only with different
function names (gds2_glock_wait versus gfs2_glock_dq_wait in the
gfs2/glock.c case).

Since first version of this patch (against 3.15) two new action
functions appeared, on in NFS and one in CIFS.  CIFS also now
uses an action function that makes the same freezer aware
schedule call as NFS.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: David Howells <dhowells@redhat.com> (fscache, keys)
Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2)
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-16 15:10:39 +02:00
Julian Anastasov
2627b7e15c ipvs: avoid netns exit crash on ip_vs_conn_drop_conntrack
commit 8f4e0a1868 ("IPVS netns exit causes crash in conntrack")
added second ip_vs_conn_drop_conntrack call instead of just adding
the needed check. As result, the first call still can cause
crash on netns exit. Remove it.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
2014-07-16 09:39:28 +09:00
Linus Torvalds
5615f9f822 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Bluetooth pairing fixes from Johan Hedberg.

 2) ieee80211_send_auth() doesn't allocate enough tail room for the SKB,
    from Max Stepanov.

 3) New iwlwifi chip IDs, from Oren Givon.

 4) bnx2x driver reads wrong PCI config space MSI register, from Yijing
    Wang.

 5) IPV6 MLD Query validation isn't strong enough, from Hangbin Liu.

 6) Fix double SKB free in openvswitch, from Andy Zhou.

 7) Fix sk_dst_set() being racey with UDP sockets, leading to strange
    crashes, from Eric Dumazet.

 8) Interpret the NAPI budget correctly in the new systemport driver,
    from Florian Fainelli.

 9) VLAN code frees percpu stats in the wrong place, leading to crashes
    in the get stats handler.  From Eric Dumazet.

10) TCP sockets doing a repair can crash with a divide by zero, because
    we invoke tcp_push() with an MSS value of zero.  Just skip that part
    of the sendmsg paths in repair mode.  From Christoph Paasch.

11) IRQ affinity bug fixes in mlx4 driver from Amir Vadai.

12) Don't ignore path MTU icmp messages with a zero mtu, machines out
    there still spit them out, and all of our per-protocol handlers for
    PMTU can cope with it just fine.  From Edward Allcutt.

13) Some NETDEV_CHANGE notifier invocations were not passing in the
    correct kind of cookie as the argument, from Loic Prylli.

14) Fix crashes in long multicast/broadcast reassembly, from Jon Paul
    Maloy.

15) ip_tunnel_lookup() doesn't interpret wildcard keys correctly, fix
    from Dmitry Popov.

16) Fix skb->sk assigned without taking a reference to 'sk' in
    appletalk, from Andrey Utkin.

17) Fix some info leaks in ULP event signalling to userspace in SCTP,
    from Daniel Borkmann.

18) Fix deadlocks in HSO driver, from Olivier Sobrie.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (93 commits)
  hso: fix deadlock when receiving bursts of data
  hso: remove unused workqueue
  net: ppp: don't call sk_chk_filter twice
  mlx4: mark napi id for gro_skb
  bonding: fix ad_select module param check
  net: pppoe: use correct channel MTU when using Multilink PPP
  neigh: sysctl - simplify address calculation of gc_* variables
  net: sctp: fix information leaks in ulpevent layer
  MAINTAINERS: update r8169 maintainer
  net: bcmgenet: fix RGMII_MODE_EN bit
  tipc: clear 'next'-pointer of message fragments before reassembly
  r8152: fix r8152_csum_workaround function
  be2net: set EQ DB clear-intr bit in be_open()
  GRE: enable offloads for GRE
  farsync: fix invalid memory accesses in fst_add_one() and fst_init_card()
  igb: do a reset on SR-IOV re-init if device is down
  igb: Workaround for i210 Errata 25: Slow System Clock
  usbnet: smsc95xx: add reset_resume function with reset operation
  dp83640: Always decode received status frames
  r8169: disable L23
  ...
2014-07-15 08:42:52 -07:00
Tejun Heo
2cf669a58d cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes()
Currently, cftypes added by cgroup_add_cftypes() are used for both the
unified default hierarchy and legacy ones and subsystems can mark each
file with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE if it has to
appear only on one of them.  This is quite hairy and error-prone.
Also, we may end up exposing interface files to the default hierarchy
without thinking it through.

cgroup_subsys will grow two separate cftype addition functions and
apply each only on the hierarchies of the matching type.  This will
allow organizing cftypes in a lot clearer way and encourage subsystems
to scrutinize the interface which is being exposed in the new default
hierarchy.

In preparation, this patch adds cgroup_add_legacy_cftypes() which
currently is a simple wrapper around cgroup_add_cftypes() and replaces
all cgroup_add_cftypes() usages with it.

While at it, this patch drops a completely spurious return from
__hugetlb_cgroup_file_init().

This patch doesn't introduce any functional differences.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2014-07-15 11:05:09 -04:00
Tejun Heo
5577964e64 cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes
Currently, cgroup_subsys->base_cftypes is used for both the unified
default hierarchy and legacy ones and subsystems can mark each file
with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE if it has to appear
only on one of them.  This is quite hairy and error-prone.  Also, we
may end up exposing interface files to the default hierarchy without
thinking it through.

cgroup_subsys will grow two separate cftype arrays and apply each only
on the hierarchies of the matching type.  This will allow organizing
cftypes in a lot clearer way and encourage subsystems to scrutinize
the interface which is being exposed in the new default hierarchy.

In preparation, this patch renames cgroup_subsys->base_cftypes to
cgroup_subsys->legacy_cftypes.  This patch is pure rename.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Aristeu Rozanski <aris@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2014-07-15 11:05:09 -04:00
Sasha Levin
3cf521f7dc net/l2tp: don't fall back on UDP [get|set]sockopt
The l2tp [get|set]sockopt() code has fallen back to the UDP functions
for socket option levels != SOL_PPPOL2TP since day one, but that has
never actually worked, since the l2tp socket isn't an inet socket.

As David Miller points out:

  "If we wanted this to work, it'd have to look up the tunnel and then
   use tunnel->sk, but I wonder how useful that would be"

Since this can never have worked so nobody could possibly have depended
on that functionality, just remove the broken code and return -EINVAL.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: James Chapman <jchapman@katalix.com>
Acked-by: David Miller <davem@davemloft.net>
Cc: Phil Turnbull <phil.turnbull@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-07-14 17:02:31 -07:00
Mathias Krause
9ecf07a1d8 neigh: sysctl - simplify address calculation of gc_* variables
The code in neigh_sysctl_register() relies on a specific layout of
struct neigh_table, namely that the 'gc_*' variables are directly
following the 'parms' member in a specific order. The code, though,
expresses this in the most ugly way.

Get rid of the ugly casts and use the 'tbl' pointer to get a handle to
the table. This way we can refer to the 'gc_*' variables directly.

Similarly seen in the grsecurity patch, written by Brad Spengler.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 14:32:51 -07:00
Daniel Borkmann
8f2e5ae40e net: sctp: fix information leaks in ulpevent layer
While working on some other SCTP code, I noticed that some
structures shared with user space are leaking uninitialized
stack or heap buffer. In particular, struct sctp_sndrcvinfo
has a 2 bytes hole between .sinfo_flags and .sinfo_ppid that
remains unfilled by us in sctp_ulpevent_read_sndrcvinfo() when
putting this into cmsg. But also struct sctp_remote_error
contains a 2 bytes hole that we don't fill but place into a skb
through skb_copy_expand() via sctp_ulpevent_make_remote_error().

Both structures are defined by the IETF in RFC6458:

* Section 5.3.2. SCTP Header Information Structure:

  The sctp_sndrcvinfo structure is defined below:

  struct sctp_sndrcvinfo {
    uint16_t sinfo_stream;
    uint16_t sinfo_ssn;
    uint16_t sinfo_flags;
    <-- 2 bytes hole  -->
    uint32_t sinfo_ppid;
    uint32_t sinfo_context;
    uint32_t sinfo_timetolive;
    uint32_t sinfo_tsn;
    uint32_t sinfo_cumtsn;
    sctp_assoc_t sinfo_assoc_id;
  };

* 6.1.3. SCTP_REMOTE_ERROR:

  A remote peer may send an Operation Error message to its peer.
  This message indicates a variety of error conditions on an
  association. The entire ERROR chunk as it appears on the wire
  is included in an SCTP_REMOTE_ERROR event. Please refer to the
  SCTP specification [RFC4960] and any extensions for a list of
  possible error formats. An SCTP error notification has the
  following format:

  struct sctp_remote_error {
    uint16_t sre_type;
    uint16_t sre_flags;
    uint32_t sre_length;
    uint16_t sre_error;
    <-- 2 bytes hole  -->
    sctp_assoc_t sre_assoc_id;
    uint8_t  sre_data[];
  };

Fix this by setting both to 0 before filling them out. We also
have other structures shared between user and kernel space in
SCTP that contains holes (e.g. struct sctp_paddrthlds), but we
copy that buffer over from user space first and thus don't need
to care about it in that cases.

While at it, we can also remove lengthy comments copied from
the draft, instead, we update the comment with the correct RFC
number where one can look it up.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 14:18:56 -07:00
Eric Dumazet
ce355e209f netfilter: nf_tables: 64bit stats need some extra synchronization
Use generic u64_stats_sync infrastructure to get proper 64bit stats,
even on 32bit arches, at no extra cost for 64bit arches.

Without this fix, 32bit arches can have some wrong counters at the time
the carry is propagated into upper word.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-07-14 12:00:17 +02:00
Pablo Neira Ayuso
38e029f14a netfilter: nf_tables: set NLM_F_DUMP_INTR if netlink dumping is stale
An updater may interfer with the dumping of any of the object lists.
Fix this by using a per-net generation counter and use the
nl_dump_check_consistent() interface so the NLM_F_DUMP_INTR flag is set
to notify userspace that it has to restart the dump since an updater
has interfered.

This patch also replaces the existing consistency checking code in the
rule dumping path since it is broken. Basically, the value that the
dump callback returns is not propagated to userspace via
netlink_dump_start().

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-07-14 12:00:16 +02:00
Pablo Neira Ayuso
e688a7f8c6 netfilter: nf_tables: safe RCU iteration on list when dumping
The dump operation through netlink is not protected by the nfnl_lock.
Thus, a reader process can be dumping any of the existing object
lists while another process can be updating the list content.

This patch resolves this situation by protecting all the object
lists with RCU in the netlink dump path which is the reader side.
The updater path is already protected via nfnl_lock, so use list
manipulation RCU-safe operations.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-07-14 11:20:45 +02:00
Jon Paul Maloy
999417549c tipc: clear 'next'-pointer of message fragments before reassembly
If the 'next' pointer of the last fragment buffer in a message is not
zeroed before reassembly, we risk ending up with a corrupt message,
since the reassembly function itself isn't doing this.

Currently, when a buffer is retrieved from the deferred queue of the
broadcast link, the next pointer is not cleared, with the result as
described above.

This commit corrects this, and thereby fixes a bug that may occur when
long broadcast messages are transmitted across dual interfaces. The bug
has been present since 40ba3cdf54 ("tipc:
message reassembly using fragment chain")

This commit should be applied to both net and net-next.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-11 15:02:10 -07:00
Amritha Nambiar
d0a7ebbc11 GRE: enable offloads for GRE
To get offloads to work with Generic Routing Encapsulation (GRE), the
outer transport header has to be reset after skb_push is done. This
patch has the support for this fix and hence GRE offloading.

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
Tested-By: Jim Young <jamesx.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-11 13:53:39 -07:00
Peter Hurley
e359a4e38d tty: Remove tty_hung_up_p() tests from tty drivers' open()
Since at least before 2.6.30, it has not been possible to observe
a hung up file pointer in a tty driver's open() method unless/until
the driver open() releases the tty_lock() (eg., before blocking).

This is because tty_open() adds the file pointer while holding
the tty_lock() _and_ doesn't release the lock until after calling
the tty driver's open() method. [ Before tty_lock(), this was
lock_kernel(). ]

Since __tty_hangup() first waits on the tty_lock() before
enumerating and hanging up the open file pointers, either
__tty_hangup() will wait for the tty_lock() or tty_open() will
not yet have added the file pointer. For example,

CPU 0                          |  CPU 1
                               |
tty_open                       |  __tty_hangup
  ..                           |    ..
  tty_lock                     |    ..
  tty_reopen                   |    tty_lock  / blocks
  ..                           |
  tty_add_file(tty, filp)      |
  ..                           |
  tty->ops->open(tty, filp)    |
    tty_port_open              |
      tty_port_block_til_ready |
        ..                     |
        while (1)              |
          ..                   |
          tty_unlock           |    / unblocks
          schedule             |    for each filp on tty->tty_files
                               |      f_ops = tty_hung_up_fops;
                               |    ..
                               |    tty_unlock
          tty_lock             |
  ..                           |
  tty_unlock                   |

Note that since tty_port_block_til_ready() and similar drop
the tty_lock while blocking, when woken, the file pointer
must then be tested for having been hung up.

Also, fix bit-rotted drivers that used extra_count to track the
port->count bump.

CC: Mikael Starvik <starvik@axis.com>
CC: Samuel Ortiz <samuel@sortiz.org>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 16:06:49 -07:00
Ben Pfaff
ac30ef832e netlink: Fix handling of error from netlink_dump().
netlink_dump() returns a negative errno value on error.  Until now,
netlink_recvmsg() directly recorded that negative value in sk->sk_err, but
that's wrong since sk_err takes positive errno values.  (This manifests as
userspace receiving a positive return value from the recv() system call,
falsely indicating success.) This bug was introduced in the commit that
started checking the netlink_dump() return value, commit b44d211 (netlink:
handle errors from netlink_dump()).

Multithreaded Netlink dumps are one way to trigger this behavior in
practice, as described in the commit message for the userspace workaround
posted here:
    http://openvswitch.org/pipermail/dev/2014-June/042339.html

This commit also fixes the same bug in netlink_poll(), introduced in commit
cd1df525d (netlink: add flow control for memory mapped I/O).

Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-09 14:33:47 -07:00
Andrey Utkin
36beddc272 appletalk: Fix socket referencing in skb
Setting just skb->sk without taking its reference and setting a
destructor is invalid. However, in the places where this was done, skb
is used in a way not requiring skb->sk setting. So dropping the setting
of skb->sk.
Thanks to Eric Dumazet <eric.dumazet@gmail.com> for correct solution.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79441
Reported-by: Ed Martin <edman007@edman007.com>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08 19:39:43 -07:00
Dmitry Popov
e0056593b6 ip_tunnel: fix ip_tunnel_lookup
This patch fixes 3 similar bugs where incoming packets might be routed into
wrong non-wildcard tunnels:

1) Consider the following setup:
    ip address add 1.1.1.1/24 dev eth0
    ip address add 1.1.1.2/24 dev eth0
    ip tunnel add ipip1 remote 2.2.2.2 local 1.1.1.1 mode ipip dev eth0
    ip link set ipip1 up

Incoming ipip packets from 2.2.2.2 were routed into ipip1 even if it has dst =
1.1.1.2. Moreover even if there was wildcard tunnel like
   ip tunnel add ipip0 remote 2.2.2.2 local any mode ipip dev eth0
but it was created before explicit one (with local 1.1.1.1), incoming ipip
packets with src = 2.2.2.2 and dst = 1.1.1.2 were still routed into ipip1.

Same issue existed with all tunnels that use ip_tunnel_lookup (gre, vti)

2)  ip address add 1.1.1.1/24 dev eth0
    ip tunnel add ipip1 remote 2.2.146.85 local 1.1.1.1 mode ipip dev eth0
    ip link set ipip1 up

Incoming ipip packets with dst = 1.1.1.1 were routed into ipip1, no matter what
src address is. Any remote ip address which has ip_tunnel_hash = 0 raised this
issue, 2.2.146.85 is just an example, there are more than 4 million of them.
And again, wildcard tunnel like
   ip tunnel add ipip0 remote any local 1.1.1.1 mode ipip dev eth0
wouldn't be ever matched if it was created before explicit tunnel like above.

Gre & vti tunnels had the same issue.

3)  ip address add 1.1.1.1/24 dev eth0
    ip tunnel add gre1 remote 2.2.146.84 local 1.1.1.1 key 1 mode gre dev eth0
    ip link set gre1 up

Any incoming gre packet with key = 1 were routed into gre1, no matter what
src/dst addresses are. Any remote ip address which has ip_tunnel_hash = 0 raised
the issue, 2.2.146.84 is just an example, there are more than 4 million of them.
Wildcard tunnel like
   ip tunnel add gre2 remote any local any key 1 mode gre dev eth0
wouldn't be ever matched if it was created before explicit tunnel like above.

All this stuff happened because while looking for a wildcard tunnel we didn't
check that matched tunnel is a wildcard one. Fixed.

Signed-off-by: Dmitry Popov <ixaphire@qrator.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08 19:35:09 -07:00
Jon Paul Maloy
29322d0db9 tipc: fix bug in multicast/broadcast message reassembly
Since commit 37e22164a8 ("tipc: rename and
move message reassembly function") reassembly of long broadcast messages
has been broken. This is because we test for a non-NULL return value
of the *buf parameter as criteria for succesful reassembly. However, this
parameter is left defined even after reception of the first fragment,
when reassebly is still incomplete. This leads to a kernel crash as soon
as a the first fragment of a long broadcast message is received.

We fix this with this commit, by implementing a stricter behavior of the
function and its return values.

This commit should be applied to both net and net-next.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08 15:55:09 -07:00
Yuchung Cheng
6e08d5e3c8 tcp: fix false undo corner cases
The undo code assumes that, upon entering loss recovery, TCP
1) always retransmit something
2) the retransmission never fails locally (e.g., qdisc drop)

so undo_marker is set in tcp_enter_recovery() and undo_retrans is
incremented only when tcp_retransmit_skb() is successful.

When the assumption is broken because TCP's cwnd is too small to
retransmit or the retransmit fails locally. The next (DUP)ACK
would incorrectly revert the cwnd and the congestion state in
tcp_try_undo_dsack() or tcp_may_undo(). Subsequent (DUP)ACKs
may enter the recovery state. The sender repeatedly enter and
(incorrectly) exit recovery states if the retransmits continue to
fail locally while receiving (DUP)ACKs.

The fix is to initialize undo_retrans to -1 and start counting on
the first retransmission. Always increment undo_retrans even if the
retransmissions fail locally because they couldn't cause DSACKs to
undo the cwnd reduction.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 21:40:48 -07:00
dingtianhong
52ad353a53 igmp: fix the problem when mc leave group
The problem was triggered by these steps:

1) create socket, bind and then setsockopt for add mc group.
   mreq.imr_multiaddr.s_addr = inet_addr("255.0.0.37");
   mreq.imr_interface.s_addr = inet_addr("192.168.1.2");
   setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));

2) drop the mc group for this socket.
   mreq.imr_multiaddr.s_addr = inet_addr("255.0.0.37");
   mreq.imr_interface.s_addr = inet_addr("0.0.0.0");
   setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq, sizeof(mreq));

3) and then drop the socket, I found the mc group was still used by the dev:

   netstat -g

   Interface       RefCnt Group
   --------------- ------ ---------------------
   eth2		   1	  255.0.0.37

Normally even though the IP_DROP_MEMBERSHIP return error, the mc group still need
to be released for the netdev when drop the socket, but this process was broken when
route default is NULL, the reason is that:

The ip_mc_leave_group() will choose the in_dev by the imr_interface.s_addr, if input addr
is NULL, the default route dev will be chosen, then the ifindex is got from the dev,
then polling the inet->mc_list and return -ENODEV, but if the default route dev is NULL,
the in_dev and ifIndex is both NULL, when polling the inet->mc_list, the mc group will be
released from the mc_list, but the dev didn't dec the refcnt for this mc group, so
when dropping the socket, the mc_list is NULL and the dev still keep this group.

v1->v2: According Hideaki's suggestion, we should align with IPv6 (RFC3493) and BSDs,
	so I add the checking for the in_dev before polling the mc_list, make sure when
	we remove the mc group, dec the refcnt to the real dev which was using the mc address.
	The problem would never happened again.

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 21:30:55 -07:00
Loic Prylli
5495119465 net: Fix NETDEV_CHANGE notifier usage causing spurious arp flush
A bug was introduced in NETDEV_CHANGE notifier sequence causing the
arp table to be sometimes spuriously cleared (including manual arp
entries marked permanent), upon network link carrier changes.

The changed argument for the notifier was applied only to a single
caller of NETDEV_CHANGE, missing among others netdev_state_change().
So upon net_carrier events induced by the network, which are
triggering a call to netdev_state_change(), arp_netdev_event() would
decide whether to clear or not arp cache based on random/junk stack
values (a kind of read buffer overflow).

Fixes: be9efd3653 ("net: pass changed flags along with NETDEV_CHANGE event")
Fixes: 6c8b4e3ff8 ("arp: flush arp cache on IFF_NOARP change")
Signed-off-by: Loic Prylli <loicp@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 21:20:01 -07:00
David S. Miller
edc1bb0bd7 Merge branch 'net_ovs_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/pshelar/openvswitch
Pravin B Shelar says:

====================
Open vSwitch

A set of fixes for net.
First bug is related flow-table management.  Second one is in sample
action. Third is related flow stats and last one add gre-err handler for ovs.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 19:39:34 -07:00
Tom Herbert
11ef7a8996 net: Performance fix for process_backlog
In process_backlog the input_pkt_queue is only checked once for new
packets and quota is artificially reduced to reflect precisely the
number of packets on the input_pkt_queue so that the loop exits
appropriately.

This patches changes the behavior to be more straightforward and
less convoluted. Packets are processed until either the quota
is met or there are no more packets to process.

This patch seems to provide a small, but noticeable performance
improvement. The performance improvement is a result of staying
in the process_backlog loop longer which can reduce number of IPI's.

Performance data using super_netperf TCP_RR with 200 flows:

Before fix:

88.06% CPU utilization
125/190/309 90/95/99% latencies
1.46808e+06 tps
1145382 intrs.sec.

With fix:

87.73% CPU utilization
122/183/296 90/95/99% latencies
1.4921e+06 tps
1021674.30 intrs./sec.

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 19:24:34 -07:00
Edward Allcutt
68b7107b62 ipv4: icmp: Fix pMTU handling for rare case
Some older router implementations still send Fragmentation Needed
errors with the Next-Hop MTU field set to zero. This is explicitly
described as an eventuality that hosts must deal with by the
standard (RFC 1191) since older standards specified that those
bits must be zero.

Linux had a generic (for all of IPv4) implementation of the algorithm
described in the RFC for searching a list of MTU plateaus for a good
value. Commit 46517008e1 ("ipv4: Kill ip_rt_frag_needed().")
removed this as part of the changes to remove the routing cache.
Subsequently any Fragmentation Needed packet with a zero Next-Hop
MTU has been discarded without being passed to the per-protocol
handlers or notifying userspace for raw sockets.

When there is a router which does not implement RFC 1191 on an
MTU limited path then this results in stalled connections since
large packets are discarded and the local protocols are not
notified so they never attempt to lower the pMTU.

One example I have seen is an OpenBSD router terminating IPSec
tunnels. It's worth pointing out that this case is distinct from
the BSD 4.2 bug which incorrectly calculated the Next-Hop MTU
since the commit in question dismissed that as a valid concern.

All of the per-protocols handlers implement the simple approach from
RFC 1191 of immediately falling back to the minimum value. Although
this is sub-optimal it is vastly preferable to connections hanging
indefinitely.

Remove the Next-Hop MTU != 0 check and allow such packets
to follow the normal path.

Fixes: 46517008e1 ("ipv4: Kill ip_rt_frag_needed().")
Signed-off-by: Edward Allcutt <edward.allcutt@openmarket.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-07 17:22:57 -07:00
Johannes Berg
08b9939997 Revert "mac80211: move "bufferable MMPDU" check to fix AP mode scan"
This reverts commit 277d916fc2 as it was
at least breaking iwlwifi by setting the IEEE80211_TX_CTL_NO_PS_BUFFER
flag in all kinds of interface modes, not only for AP mode where it is
appropriate.

To avoid reintroducing the original problem, explicitly check for probe
request frames in the multicast buffering code.

Cc: stable@vger.kernel.org
Fixes: 277d916fc2 ("mac80211: move "bufferable MMPDU" check to fix AP mode scan")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-07-07 12:20:45 +02:00
Christoph Paasch
5924f17a8a tcp: Fix divide by zero when pushing during tcp-repair
When in repair-mode and TCP_RECV_QUEUE is set, we end up calling
tcp_push with mss_now being 0. If data is in the send-queue and
tcp_set_skb_tso_segs gets called, we crash because it will divide by
mss_now:

[  347.151939] divide error: 0000 [#1] SMP
[  347.152907] Modules linked in:
[  347.152907] CPU: 1 PID: 1123 Comm: packetdrill Not tainted 3.16.0-rc2 #4
[  347.152907] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  347.152907] task: f5b88540 ti: f3c82000 task.ti: f3c82000
[  347.152907] EIP: 0060:[<c1601359>] EFLAGS: 00210246 CPU: 1
[  347.152907] EIP is at tcp_set_skb_tso_segs+0x49/0xa0
[  347.152907] EAX: 00000b67 EBX: f5acd080 ECX: 00000000 EDX: 00000000
[  347.152907] ESI: f5a28f40 EDI: f3c88f00 EBP: f3c83d10 ESP: f3c83d00
[  347.152907]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[  347.152907] CR0: 80050033 CR2: 083158b0 CR3: 35146000 CR4: 000006b0
[  347.152907] Stack:
[  347.152907]  c167f9d9 f5acd080 000005b4 00000002 f3c83d20 c16013e6 f3c88f00 f5acd080
[  347.152907]  f3c83da0 c1603b5a f3c83d38 c10a0188 00000000 00000000 f3c83d84 c10acc85
[  347.152907]  c1ad5ec0 00000000 00000000 c1ad679c 010003e0 00000000 00000000 f3c88fc8
[  347.152907] Call Trace:
[  347.152907]  [<c167f9d9>] ? apic_timer_interrupt+0x2d/0x34
[  347.152907]  [<c16013e6>] tcp_init_tso_segs+0x36/0x50
[  347.152907]  [<c1603b5a>] tcp_write_xmit+0x7a/0xbf0
[  347.152907]  [<c10a0188>] ? up+0x28/0x40
[  347.152907]  [<c10acc85>] ? console_unlock+0x295/0x480
[  347.152907]  [<c10ad24f>] ? vprintk_emit+0x1ef/0x4b0
[  347.152907]  [<c1605716>] __tcp_push_pending_frames+0x36/0xd0
[  347.152907]  [<c15f4860>] tcp_push+0xf0/0x120
[  347.152907]  [<c15f7641>] tcp_sendmsg+0xf1/0xbf0
[  347.152907]  [<c116d920>] ? kmem_cache_free+0xf0/0x120
[  347.152907]  [<c106a682>] ? __sigqueue_free+0x32/0x40
[  347.152907]  [<c106a682>] ? __sigqueue_free+0x32/0x40
[  347.152907]  [<c114f0f0>] ? do_wp_page+0x3e0/0x850
[  347.152907]  [<c161c36a>] inet_sendmsg+0x4a/0xb0
[  347.152907]  [<c1150269>] ? handle_mm_fault+0x709/0xfb0
[  347.152907]  [<c15a006b>] sock_aio_write+0xbb/0xd0
[  347.152907]  [<c1180b79>] do_sync_write+0x69/0xa0
[  347.152907]  [<c1181023>] vfs_write+0x123/0x160
[  347.152907]  [<c1181d55>] SyS_write+0x55/0xb0
[  347.152907]  [<c167f0d8>] sysenter_do_call+0x12/0x28

This can easily be reproduced with the following packetdrill-script (the
"magic" with netem, sk_pacing and limit_output_bytes is done to prevent
the kernel from pushing all segments, because hitting the limit without
doing this is not so easy with packetdrill):

0   socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0  setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

+0  bind(3, ..., ...) = 0
+0  listen(3, 1) = 0

+0  < S 0:0(0) win 32792 <mss 1460>
+0  > S. 0:0(0) ack 1 <mss 1460>
+0.1  < . 1:1(0) ack 1 win 65000

+0  accept(3, ..., ...) = 4

// This forces that not all segments of the snd-queue will be pushed
+0 `tc qdisc add dev tun0 root netem delay 10ms`
+0 `sysctl -w net.ipv4.tcp_limit_output_bytes=2`
+0 setsockopt(4, SOL_SOCKET, 47, [2], 4) = 0

+0 write(4,...,10000) = 10000
+0 write(4,...,10000) = 10000

// Set tcp-repair stuff, particularly TCP_RECV_QUEUE
+0 setsockopt(4, SOL_TCP, 19, [1], 4) = 0
+0 setsockopt(4, SOL_TCP, 20, [1], 4) = 0

// This now will make the write push the remaining segments
+0 setsockopt(4, SOL_SOCKET, 47, [20000], 4) = 0
+0 `sysctl -w net.ipv4.tcp_limit_output_bytes=130000`

// Now we will crash
+0 write(4,...,1000) = 1000

This happens since ec34232575 (tcp: fix retransmission in repair
mode). Prior to that, the call to tcp_push was prevented by a check for
tp->repair.

The patch fixes it, by adding the new goto-label out_nopush. When exiting
tcp_sendmsg and a push is not required, which is the case for tp->repair,
we go to this label.

When repairing and calling send() with TCP_RECV_QUEUE, the data is
actually put in the receive-queue. So, no push is required because no
data has been added to the send-queue.

Cc: Andrew Vagin <avagin@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Fixes: ec34232575 (tcp: fix retransmission in repair mode)
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Acked-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-02 18:21:03 -07:00