Commit Graph

615249 Commits

Author SHA1 Message Date
Liping Zhang 12be15dd5a netfilter: nfnetlink_acct: fix race between nfacct del and xt_nfacct destroy
Suppose that we input the following commands at first:
  # nfacct add test
  # iptables -A INPUT -m nfacct --nfacct-name test

And now "test" acct's refcnt is 2, but later when we try to delete the
"test" nfacct and the related iptables rule at the same time, race maybe
happen:
      CPU0                                    CPU1
  nfnl_acct_try_del                      nfnl_acct_put
  atomic_dec_and_test //ref=1,testfail          -
       -                                 atomic_dec_and_test //ref=0,testok
       -                                 kfree_rcu
  atomic_inc //ref=1                            -

So after the rcu grace period, nf_acct will be freed but it is still linked
in the nfnl_acct_list, and we can access it later, then oops will happen.

Convert atomic_dec_and_test and atomic_inc combinaiton to one atomic
operation atomic_cmpxchg here to fix this problem.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18 15:16:36 +02:00
Eric Dumazet dcbe35909c netfilter: tproxy: properly refcount tcp listeners
inet_lookup_listener() and inet6_lookup_listener() no longer
take a reference on the found listener.

This minimal patch adds back the refcounting, but we might do
this differently in net-next later.

Fixes: 3b24d854cb ("tcp/dccp: do not touch listener sk_refcnt under synflood")
Reported-and-tested-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18 00:51:13 +02:00
Liping Zhang aca300183e netfilter: nfnetlink_acct: report overquota to the right netns
We should report the over quota message to the right net namespace
instead of the init netns.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18 00:38:23 +02:00
Liping Zhang 2497b84625 netfilter: nfnetlink_log: add "nf-logger-3-1" module alias name
Otherwise, if nfnetlink_log.ko is not loaded, we cannot add rules
to log packets to the userspace when we specify it with arp family,
such as:

  # nft add rule arp filter input log group 0
  <cmdline>:1:1-37: Error: Could not process rule: No such file or
  directory
  add rule arp filter input log group 0
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-17 17:44:53 +02:00
Liping Zhang e77e6ff502 netfilter: conntrack: do not dump other netns's conntrack entries via proc
We should skip the conntracks that belong to a different namespace,
otherwise other unrelated netns's conntrack entries will be dumped via
/proc/net/nf_conntrack.

Fixes: 56d52d4892 ("netfilter: conntrack: use a single hashtable for all namespaces")
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-17 17:41:58 +02:00
David S. Miller a1560dd7a4 Merge branch 'mediatek-fixes'
Sean Wang says:

====================
mediatek: Fix warning and issue

This patch set fixes the following warning and issues

v1 -> v2: Fix message typos and add coverletter

v2 -> v3: Split from the previous series for submitting bug fixes
as a series targeting 'net'
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 23:02:45 -07:00
sean.wang@mediatek.com 55a4e77819 net: ethernet: mediatek: fix runtime warning raised by inconsistent struct device pointers passed to DMA API
Runtime warning occurs if DMA-API debug feature is enabled that would be
raised by pointers passed to DMA API as arguments to inconsistent struct
device objects, so that the patch makes them usage aligned between DMA
operations such as dma_map_*() and dma_unmap_*() to eliminate the warning.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 23:02:44 -07:00
sean.wang@mediatek.com b2025c7cc9 net: ethernet: mediatek: fix flow control settings on GMAC0 is not being enabled properly
Commit 08ef55c6f2
("net-next: mediatek: fix gigabit and flow control advertisement")
had supported proper flow control settings for GMAC1. But for GMAC0,

1.GMAC0 shares the common logic with GMAC1 inside mtk_phy_link_adjust()
to adapt various settings for the target phy.

2.GMAC0 uses fixed-phy to connect to a builtin gigabit switch with
fixed link speed as commit 0c72c50f6f
("net-next: mediatek: add fixed-phy support") describes.

3.However, fixed-phy doesn't enable SUPPORTED_Pause & SUPPORTED_Asym_Pause
supported flag on default that would cause mtk_phy_link_adjust() not to
enable flow control setting on GMAC0 properly and cause packet dropped
when high traffic.

Due to these reasons, the patch adds SUPPORTED_Pause & SUPPORTED_Asym_Pause
supported flags on fixed-phy used by the driver to have proper handling on
the both GMAC with the shared common logic.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 23:02:44 -07:00
sean.wang@mediatek.com 8ca7f4fe07 net: ethernet: mediatek: fix RMII mode and add REVMII supported by GMAC
The patch fixes up the incorrect setup of reduced MII (RMII) on GMAC
and adds the supplement for the setup of reverse MII (REVMII) on GMAC
, and rearranges the error handling for invalid PHY argument.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 23:02:44 -07:00
Vegard Nossum d2fbdf76b8 tipc: fix NULL pointer dereference in shutdown()
tipc_msg_create() can return a NULL skb and if so, we shouldn't try to
call tipc_node_xmit_skb() on it.

    general protection fault: 0000 [#1] PREEMPT SMP KASAN
    CPU: 3 PID: 30298 Comm: trinity-c0 Not tainted 4.7.0-rc7+ #19
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
    task: ffff8800baf09980 ti: ffff8800595b8000 task.ti: ffff8800595b8000
    RIP: 0010:[<ffffffff830bb46b>]  [<ffffffff830bb46b>] tipc_node_xmit_skb+0x6b/0x140
    RSP: 0018:ffff8800595bfce8  EFLAGS: 00010246
    RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003023b0e0
    RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffffffff83d12580
    RBP: ffff8800595bfd78 R08: ffffed000b2b7f32 R09: 0000000000000000
    R10: fffffbfff0759725 R11: 0000000000000000 R12: 1ffff1000b2b7f9f
    R13: ffff8800595bfd58 R14: ffffffff83d12580 R15: dffffc0000000000
    FS:  00007fcdde242700(0000) GS:ffff88011af80000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007fcddde1db10 CR3: 000000006874b000 CR4: 00000000000006e0
    DR0: 00007fcdde248000 DR1: 00007fcddd73d000 DR2: 00007fcdde248000
    DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000090602
    Stack:
     0000000000000018 0000000000000018 0000000041b58ab3 ffffffff83954208
     ffffffff830bb400 ffff8800595bfd30 ffffffff8309d767 0000000000000018
     0000000000000018 ffff8800595bfd78 ffffffff8309da1a 00000000810ee611
    Call Trace:
     [<ffffffff830c84a3>] tipc_shutdown+0x553/0x880
     [<ffffffff825b4a3b>] SyS_shutdown+0x14b/0x170
     [<ffffffff8100334c>] do_syscall_64+0x19c/0x410
     [<ffffffff83295ca5>] entry_SYSCALL64_slow_path+0x25/0x25
    Code: 90 00 b4 0b 83 c7 00 f1 f1 f1 f1 4c 8d 6d e0 c7 40 04 00 00 00 f4 c7 40 08 f3 f3 f3 f3 48 89 d8 48 c1 e8 03 c7 45 b4 00 00 00 00 <80> 3c 30 00 75 78 48 8d 7b 08 49 8d 75 c0 48 b8 00 00 00 00 00
    RIP  [<ffffffff830bb46b>] tipc_node_xmit_skb+0x6b/0x140
     RSP <ffff8800595bfce8>
    ---[ end trace 57b0484e351e71f1 ]---

I feel like we should maybe return -ENOMEM or -ENOBUFS, but I'm not sure
userspace is equipped to handle that. Anyway, this is better than a GPF
and looks somewhat consistent with other tipc_msg_create() callers.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:55:36 -07:00
David S. Miller a8545b60a8 Merge branch 'hv_netvsc-VF-removal-fixes'
Vitaly Kuznetsov says:

====================
hv_netvsc: fixes for VF removal path

Kernel crash is reported after VF is removed and detached from netvsc
device. Turns out we have multiple different (but related) issues on the
VF removal path which I'm trying to address with PATCHes 2-5 of this
series. PATCH1 is required to support the change.

Changes since v1:
- Re-arrange patches in the series to not introduce new issues [David Miller]
- Add PATCH5 which fixes a new issue I discovered while testing.
- Add Haiyang' A-b tags to PATCH1-4

With regards to Stephen's suggestion: I believe that switching to using RCU
and eliminating vf_use_cnt/vf_inject is the right thing to do long-term, we
can either put this on top of this series or do it later in net-next.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:08 -07:00
Vitaly Kuznetsov 0dbff144a1 hv_netvsc: fix bonding devices check in netvsc_netdev_event()
Bonding driver sets IFF_BONDING on both master (the bonding device) and
slave (the real NIC) devices and in netvsc_netdev_event() we want to skip
master devices only. Currently, there is an uncertainty when a slave
interface is removed: if bonding module comes first in netdev_chain it
clears IFF_BONDING flag on the netdev and netvsc_netdev_event() correctly
handles NETDEV_UNREGISTER event, but in case netvsc comes first on the
chain it sees the device with IFF_BONDING still attached and skips it. As
we still hold vf_netdev pointer to the device we crash on the next inject.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:07 -07:00
Vitaly Kuznetsov 0f20d795f7 hv_netvsc: protect module refcount by checking net_device_ctx->vf_netdev
We're not guaranteed to see NETDEV_REGISTER/NETDEV_UNREGISTER notifications
only once per VF but we increase/decrease module refcount unconditionally.
Check vf_netdev to make sure we don't take/release it twice. We presume
that only one VF per netvsc device may exist.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:07 -07:00
Vitaly Kuznetsov 57c1826b99 hv_netvsc: reset vf_inject on VF removal
We reset vf_inject on VF going down (netvsc_vf_down()) but we don't on
VF removal (netvsc_unregister_vf()) so vf_inject stays 'true' while
vf_netdev is already NULL and we're trying to inject packets into NULL
net device in netvsc_recv_callback() causing kernel to crash.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:07 -07:00
Vitaly Kuznetsov d072218f21 hv_netvsc: avoid deadlocks between rtnl lock and vf_use_cnt wait
Here is a deadlock scenario:
- netvsc_vf_up() schedules netvsc_notify_peers() work and quits.
- netvsc_vf_down() runs before netvsc_notify_peers() gets executed. As it
  is being executed from netdev notifier chain we hold rtnl lock when we
  get here.
- we enter while (atomic_read(&net_device_ctx->vf_use_cnt) != 0) loop and
  wait till netvsc_notify_peers() drops vf_use_cnt.
- netvsc_notify_peers() starts on some other CPU but netdev_notify_peers()
  will hang on rtnl_lock().
- deadlock!

Instead of introducing additional synchronization I suggest we drop
gwrk.dwrk completely and call NETDEV_NOTIFY_PEERS directly. As we're
acting under rtnl lock this is legitimate.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:07 -07:00
Vitaly Kuznetsov f9a7da9130 hv_netvsc: don't lose VF information
struct netvsc_device is not suitable for storing VF information as this
structure is being destroyed on MTU change / set channel operation (see
rndis_filter_device_remove()). Move all VF related stuff to struct
net_device_context which is persistent.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:48:07 -07:00
Simon Horman 3d7b332092 gre: set inner_protocol on xmit
Ensure that the inner_protocol is set on transmit so that GSO segmentation,
which relies on that field, works correctly.

This is achieved by setting the inner_protocol in gre_build_header rather
than each caller of that function. It ensures that the inner_protocol is
set when gre_fb_xmit() is used to transmit GRE which was not previously the
case.

I have observed this is not the case when OvS transmits GRE using
lwtunnel metadata (which it always does).

Fixes: 3872035241 ("gre: Use inner_proto to obtain inner header protocol")
Cc: Pravin Shelar <pshelar@ovn.org>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 13:37:12 -07:00
Lorenzo Colitti 5e45789698 net: ipv6: Fix ping to link-local addresses.
ping_v6_sendmsg does not set flowi6_oif in response to
sin6_scope_id or sk_bound_dev_if, so it is not possible to use
these APIs to ping an IPv6 address on a different interface.
Instead, it sets flowi6_iif, which is incorrect but harmless.

Stop setting flowi6_iif, and support various ways of setting oif
in the same priority order used by udpv6_sendmsg.

Tested: https://android-review.googlesource.com/#/c/254470/
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 12:19:09 -07:00
Vegard Nossum 12311959ec rhashtable: fix shift by 64 when shrinking
I got this:

    ================================================================================
    UBSAN: Undefined behaviour in ./include/linux/log2.h:63:13
    shift exponent 64 is too large for 64-bit type 'long unsigned int'
    CPU: 1 PID: 721 Comm: kworker/1:1 Not tainted 4.8.0-rc1+ #87
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
    Workqueue: events rht_deferred_worker
     0000000000000000 ffff88011661f8d8 ffffffff82344f50 0000000041b58ab3
     ffffffff84f98000 ffffffff82344ea4 ffff88011661f900 ffff88011661f8b0
     0000000000000001 ffff88011661f6b8 dffffc0000000000 ffffffff867f7640
    Call Trace:
     [<ffffffff82344f50>] dump_stack+0xac/0xfc
     [<ffffffff82344ea4>] ? _atomic_dec_and_lock+0xc4/0xc4
     [<ffffffff8242f5b8>] ubsan_epilogue+0xd/0x8a
     [<ffffffff82430c41>] __ubsan_handle_shift_out_of_bounds+0x255/0x29a
     [<ffffffff824309ec>] ? __ubsan_handle_out_of_bounds+0x180/0x180
     [<ffffffff84003436>] ? nl80211_req_set_reg+0x256/0x2f0
     [<ffffffff812112ba>] ? print_context_stack+0x8a/0x160
     [<ffffffff81200031>] ? amd_pmu_reset+0x341/0x380
     [<ffffffff823af808>] rht_deferred_worker+0x1618/0x1790
     [<ffffffff823af808>] ? rht_deferred_worker+0x1618/0x1790
     [<ffffffff823ae1f0>] ? rhashtable_jhash2+0x370/0x370
     [<ffffffff8134c12d>] ? process_one_work+0x6fd/0x1970
     [<ffffffff8134c1cf>] process_one_work+0x79f/0x1970
     [<ffffffff8134c12d>] ? process_one_work+0x6fd/0x1970
     [<ffffffff8134ba30>] ? try_to_grab_pending+0x4c0/0x4c0
     [<ffffffff8134d564>] ? worker_thread+0x1c4/0x1340
     [<ffffffff8134d8ff>] worker_thread+0x55f/0x1340
     [<ffffffff845e904f>] ? __schedule+0x4df/0x1d40
     [<ffffffff8134d3a0>] ? process_one_work+0x1970/0x1970
     [<ffffffff8134d3a0>] ? process_one_work+0x1970/0x1970
     [<ffffffff813642f7>] kthread+0x237/0x390
     [<ffffffff813640c0>] ? __kthread_parkme+0x280/0x280
     [<ffffffff845f8c93>] ? _raw_spin_unlock_irq+0x33/0x50
     [<ffffffff845f95df>] ret_from_fork+0x1f/0x40
     [<ffffffff813640c0>] ? __kthread_parkme+0x280/0x280
    ================================================================================

roundup_pow_of_two() is undefined when called with an argument of 0, so
let's avoid the call and just fall back to ht->p.min_size (which should
never be smaller than HASH_MIN_SIZE).

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-15 11:10:09 -07:00
Vincent eb8fc32354 mlxsw: spectrum_router: Fix use after free
In mlxsw_sp_router_fib4_add_info_destroy(), the fib_entry pointer is used
after it has been freed by mlxsw_sp_fib_entry_destroy(). Use a temporary
variable to fix this.

Fixes: 61c503f976 ("mlxsw: spectrum_router: Implement fib4 add/del switchdev obj ops")
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: Jiri Pirko <jiri@mellanox.com>
Acked-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-14 21:32:05 -07:00
Florian Westphal 4cf0b354d9 rhashtable: avoid large lock-array allocations
Sander reports following splat after netfilter nat bysrc table got
converted to rhashtable:

swapper/0: page allocation failure: order:3, mode:0x2084020(GFP_ATOMIC|__GFP_COMP)
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.0-rc1 [..]
 [<ffffffff811633ed>] warn_alloc_failed+0xdd/0x140
 [<ffffffff811638b1>] __alloc_pages_nodemask+0x3e1/0xcf0
 [<ffffffff811a72ed>] alloc_pages_current+0x8d/0x110
 [<ffffffff8117cb7f>] kmalloc_order+0x1f/0x70
 [<ffffffff811aec19>] __kmalloc+0x129/0x140
 [<ffffffff8146d561>] bucket_table_alloc+0xc1/0x1d0
 [<ffffffff8146da1d>] rhashtable_insert_rehash+0x5d/0xe0
 [<ffffffff819fcfff>] nf_nat_setup_info+0x2ef/0x400

The failure happens when allocating the spinlock array.
Even with GFP_KERNEL its unlikely for such a large allocation
to succeed.

Thomas Graf pointed me at inet_ehash_locks_alloc(), so in addition
to adding NOWARN for atomic allocations this also makes the bucket-array
sizing more conservative.

In commit 095dc8e0c3 ("tcp: fix/cleanup inet_ehash_locks_alloc()"),
Eric Dumazet says: "Budget 2 cache lines per cpu worth of 'spinlocks'".
IOW, consider size needed by a single spinlock when determining
number of locks per cpu.  So with 64 byte per cacheline and 4 byte per
spinlock this gives 32 locks per cpu.

Resulting size of the lock-array (sizeof(spinlock) == 4):

cpus:    1   2   4   8   16   32   64
old:    1k  1k  4k  8k  16k  16k  16k
new:   128 256 512  1k   2k   4k   8k

8k allocation should have decent chance of success even
with GFP_ATOMIC, and should not fail with GFP_KERNEL.

With 72-byte spinlock (LOCKDEP):
cpus :   1   2
old:    9k 18k
new:   ~2k ~4k

Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Suggested-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-14 21:12:57 -07:00
Sabrina Dubroca 952fcfd08c net: remove type_check from dev_get_nest_level()
The idea for type_check in dev_get_nest_level() was to count the number
of nested devices of the same type (currently, only macvlan or vlan
devices).
This prevented the false positive lockdep warning on configurations such
as:

eth0 <--- macvlan0 <--- vlan0 <--- macvlan1

However, this doesn't prevent a warning on a configuration such as:

eth0 <--- macvlan0 <--- vlan0
eth1 <--- vlan1 <--- macvlan1

In this case, all the locks end up with a nesting subclass of 1, so
lockdep thinks that there is still a deadlock:

- in the first case we have (macvlan_netdev_addr_lock_key, 1) and then
  take (vlan_netdev_xmit_lock_key, 1)
- in the second case, we have (vlan_netdev_xmit_lock_key, 1) and then
  take (macvlan_netdev_addr_lock_key, 1)

By removing the linktype check in dev_get_nest_level() and always
incrementing the nesting depth, lockdep considers this configuration
valid.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-13 15:15:54 -07:00
Sabrina Dubroca e200387245 macsec: fix lockdep splats when nesting devices
Currently, trying to setup a vlan over a macsec device, or other
combinations of devices, triggers a lockdep warning.

Use netdev_lockdep_set_classes and ndo_get_lock_subclass, similar to
what macvlan does.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-13 15:15:54 -07:00
Mike Manning bc561632dd net: ipv6: Do not keep IPv6 addresses when IPv6 is disabled
If IPv6 is disabled when the option is set to keep IPv6
addresses on link down, userspace is unaware of this as
there is no such indication via netlink. The solution is to
remove the IPv6 addresses in this case, which results in
netlink messages indicating removal of addresses in the
usual manner. This fix also makes the behavior consistent
with the case of having IPv6 disabled first, which stops
IPv6 addresses from being added.

Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-13 15:14:00 -07:00
Vegard Nossum 54236ab09e net/sctp: always initialise sctp_ht_iter::start_fail
sctp_transport_seq_start() does not currently clear iter->start_fail on
success, but relies on it being zero when it is allocated (by
seq_open_net()).

This can be a problem in the following sequence:

    open() // allocates iter (and implicitly sets iter->start_fail = 0)
    read()
     - iter->start() // fails and sets iter->start_fail = 1
     - iter->stop() // doesn't call sctp_transport_walk_stop() (correct)
    read() again
     - iter->start() // succeeds, but doesn't change iter->start_fail
     - iter->stop() // doesn't call sctp_transport_walk_stop() (wrong)

We should initialize sctp_ht_iter::start_fail to zero if ->start()
succeeds, otherwise it's possible that we leave an old value of 1 there,
which will cause ->stop() to not call sctp_transport_walk_stop(), which
causes all sorts of problems like not calling rcu_read_unlock() (and
preempt_enable()), eventually leading to more warnings like this:

    BUG: sleeping function called from invalid context at mm/slab.h:388
    in_atomic(): 0, irqs_disabled(): 0, pid: 16551, name: trinity-c2
    Preemption disabled at:[<ffffffff819bceb6>] rhashtable_walk_start+0x46/0x150

     [<ffffffff81149abb>] preempt_count_add+0x1fb/0x280
     [<ffffffff83295892>] _raw_spin_lock+0x12/0x40
     [<ffffffff819bceb6>] rhashtable_walk_start+0x46/0x150
     [<ffffffff82ec665f>] sctp_transport_walk_start+0x2f/0x60
     [<ffffffff82edda1d>] sctp_transport_seq_start+0x4d/0x150
     [<ffffffff81439e50>] traverse+0x170/0x850
     [<ffffffff8143aeec>] seq_read+0x7cc/0x1180
     [<ffffffff814f996c>] proc_reg_read+0xbc/0x180
     [<ffffffff813d0384>] do_loop_readv_writev+0x134/0x210
     [<ffffffff813d2a95>] do_readv_writev+0x565/0x660
     [<ffffffff813d6857>] vfs_readv+0x67/0xa0
     [<ffffffff813d6c16>] do_preadv+0x126/0x170
     [<ffffffff813d710c>] SyS_preadv+0xc/0x10
     [<ffffffff8100334c>] do_syscall_64+0x19c/0x410
     [<ffffffff83296225>] return_from_SYSCALL_64+0x0/0x6a
     [<ffffffffffffffff>] 0xffffffffffffffff

Notice that this is a subtly different stacktrace from the one in commit
5fc382d875 ("net/sctp: terminate rhashtable walk correctly").

Cc: Xin Long <lucien.xin@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-By: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-13 15:10:16 -07:00