linux-toradex.git/net, branch v4.9.76

kernel: make groups_sort calling a responsibility group_info allocators

2018-01-10T08:29:52+00:00

commit bdcf0a423ea1c40bbb40e7ee483b50fc8aa3d758 upstream.

In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.

This patch:
 - Make groups_sort globally visible.
 - Move the call to groups_sort to the modifiers of group_info
 - Remove the call to groups_sort from set_groups

Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker 
Reviewed-by: Matthew Wilcox 
Reviewed-by: NeilBrown 
Acked-by: "J. Bruce Fields" 
Cc: Al Viro 
Cc: Martin Schwidefsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tcp_bbr: reset long-term bandwidth sampling on loss recovery undo

2018-01-05T14:46:31+00:00

commit 600647d467c6d04b3954b41a6ee1795b5ae00550 upstream.

Fix BBR so that upon notification of a loss recovery undo BBR resets
long-term bandwidth sampling.

Under high reordering, reordering events can be interpreted as loss.
If the reordering and spurious loss estimates are high enough, this
can cause BBR to spuriously estimate that we are seeing loss rates
high enough to trigger long-term bandwidth estimation. To avoid that
problem, this commit resets long-term bandwidth sampling on loss
recovery undo events.

Signed-off-by: Neal Cardwell 
Reviewed-by: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp_bbr: reset full pipe detection on loss recovery undo

2018-01-05T14:46:31+00:00

commit 2f6c498e4f15d27852c04ed46d804a39137ba364 upstream.

Fix BBR so that upon notification of a loss recovery undo BBR resets
the full pipe detection (STARTUP exit) state machine.

Under high reordering, reordering events can be interpreted as loss.
If the reordering and spurious loss estimates are high enough, this
could previously cause BBR to spuriously estimate that the pipe is
full.

Since spurious loss recovery means that our overall sending will have
slowed down spuriously, this commit gives a flow more time to probe
robustly for bandwidth and decide the pipe is really full.

Signed-off-by: Neal Cardwell 
Reviewed-by: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tcp: invalidate rate samples during SACK reneging

2018-01-02T19:35:13+00:00

[ Upstream commit d4761754b4fb2ef8d9a1e9d121c4bec84e1fe292 ]

Mark tcp_sock during a SACK reneging event and invalidate rate samples
while marked. Such rate samples may overestimate bw by including packets
that were SACKed before reneging.

< ack 6001 win 10000 sack 7001:38001
< ack 7001 win 0 sack 8001:38001 // Reneg detected
> seq 7001:8001 // RTO, SACK cleared.
< ack 38001 win 10000

In above example the rate sample taken after the last ack will count
7001-38001 as delivered while the actual delivery rate likely could
be much lower i.e. 7001-8001.

This patch adds a new field tcp_sock.sack_reneg and marks it when we
declare SACK reneging and entering TCP_CA_Loss, and unmarks it after
the last rate sample was taken before moving back to TCP_CA_Open. This
patch also invalidates rate samples taken while tcp_sock.is_sack_reneg
is set.

Fixes: b9f64820fb22 ("tcp: track data delivery rate for a TCP connection")
Signed-off-by: Yousuk Seung 
Signed-off-by: Neal Cardwell 
Signed-off-by: Yuchung Cheng 
Acked-by: Soheil Hassas Yeganeh 
Acked-by: Eric Dumazet 
Acked-by: Priyaranjan Jha 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sock: free skb in skb_complete_tx_timestamp on error

2018-01-02T19:35:13+00:00

[ Upstream commit 35b99dffc3f710cafceee6c8c6ac6a98eb2cb4bf ]

skb_complete_tx_timestamp must ingest the skb it is passed. Call
kfree_skb if the skb cannot be enqueued.

Fixes: b245be1f4db1 ("net-timestamp: no-payload only sysctl")
Fixes: 9ac25fc06375 ("net: fix socket refcounting in skb_complete_tx_timestamp()")
Reported-by: Richard Cochran 
Signed-off-by: Willem de Bruijn 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Fix double free and memory corruption in get_net_ns_by_id()

2018-01-02T19:35:13+00:00

[ Upstream commit 21b5944350052d2583e82dd59b19a9ba94a007f0 ]

(I can trivially verify that that idr_remove in cleanup_net happens
 after the network namespace count has dropped to zero --EWB)

Function get_net_ns_by_id() does not check for net::count
after it has found a peer in netns_ids idr.

It may dereference a peer, after its count has already been
finaly decremented. This leads to double free and memory
corruption:

put_net(peer)                                   rtnl_lock()
atomic_dec_and_test(&peer->count) [count=0]     ...
__put_net(peer)                                 get_net_ns_by_id(net, id)
  spin_lock(&cleanup_list_lock)
  list_add(&net->cleanup_list, &cleanup_list)
  spin_unlock(&cleanup_list_lock)
queue_work()                                      peer = idr_find(&net->netns_ids, id)
  |                                               get_net(peer) [count=1]
  |                                               ...
  |                                               (use after final put)
  v                                               ...
  cleanup_net()                                   ...
    spin_lock(&cleanup_list_lock)                 ...
    list_replace_init(&cleanup_list, ..)          ...
    spin_unlock(&cleanup_list_lock)               ...
    ...                                           ...
    ...                                           put_net(peer)
    ...                                             atomic_dec_and_test(&peer->count) [count=0]
    ...                                               spin_lock(&cleanup_list_lock)
    ...                                               list_add(&net->cleanup_list, &cleanup_list)
    ...                                               spin_unlock(&cleanup_list_lock)
    ...                                             queue_work()
    ...                                           rtnl_unlock()
    rtnl_lock()                                   ...
    for_each_net(tmp) {                           ...
      id = __peernet2id(tmp, peer)                ...
      spin_lock_irq(&tmp->nsid_lock)              ...
      idr_remove(&tmp->netns_ids, id)             ...
      ...                                         ...
      net_drop_ns()                               ...
	net_free(peer)                            ...
    }                                             ...
  |
  v
  cleanup_net()
    ...
    (Second free of peer)

Also, put_net() on the right cpu may reorder with left's cpu
list_replace_init(&cleanup_list, ..), and then cleanup_list
will be corrupted.

Since cleanup_net() is executed in worker thread, while
put_net(peer) can happen everywhere, there should be
enough time for concurrent get_net_ns_by_id() to pick
the peer up, and the race does not seem to be unlikely.
The patch fixes the problem in standard way.

(Also, there is possible problem in peernet2id_alloc(), which requires
check for net::count under nsid_lock and maybe_get_net(peer), but
in current stable kernel it's used under rtnl_lock() and it has to be
safe. Openswitch begun to use peernet2id_alloc(), and possibly it should
be fixed too. While this is not in stable kernel yet, so I'll send
a separate message to netdev@ later).

Cc: Nicolas Dichtel 
Signed-off-by: Kirill Tkhai 
Fixes: 0c7aecd4bde4 "netns: add rtnl cmd to add and get peer netns ids"
Reviewed-by: Andrey Ryabinin 
Reviewed-by: "Eric W. Biederman" 
Signed-off-by: Eric W. Biederman 
Reviewed-by: Eric Dumazet 
Acked-by: Nicolas Dichtel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: bridge: fix early call to br_stp_change_bridge_id and plug newlink leaks

2018-01-02T19:35:12+00:00

[ Upstream commit 84aeb437ab98a2bce3d4b2111c79723aedfceb33 ]

The early call to br_stp_change_bridge_id in bridge's newlink can cause
a memory leak if an error occurs during the newlink because the fdb
entries are not cleaned up if a different lladdr was specified, also
another minor issue is that it generates fdb notifications with
ifindex = 0. Another unrelated memory leak is the bridge sysfs entries
which get added on NETDEV_REGISTER event, but are not cleaned up in the
newlink error path. To remove this special case the call to
br_stp_change_bridge_id is done after netdev register and we cleanup the
bridge on changelink error via br_dev_delete to plug all leaks.

This patch makes netlink bridge destruction on newlink error the same as
dellink and ioctl del which is necessary since at that point we have a
fully initialized bridge device.

To reproduce the issue:
$ ip l add br0 address 00:11:22:33:44:55 type bridge group_fwd_mask 1
RTNETLINK answers: Invalid argument

$ rmmod bridge
[ 1822.142525] =============================================================================
[ 1822.143640] BUG bridge_fdb_cache (Tainted: G           O    ): Objects remaining in bridge_fdb_cache on __kmem_cache_shutdown()
[ 1822.144821] -----------------------------------------------------------------------------

[ 1822.145990] Disabling lock debugging due to kernel taint
[ 1822.146732] INFO: Slab 0x0000000092a844b2 objects=32 used=2 fp=0x00000000fef011b0 flags=0x1ffff8000000100
[ 1822.147700] CPU: 2 PID: 13584 Comm: rmmod Tainted: G    B      O     4.15.0-rc2+ #87
[ 1822.148578] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 1822.150008] Call Trace:
[ 1822.150510]  dump_stack+0x78/0xa9
[ 1822.151156]  slab_err+0xb1/0xd3
[ 1822.151834]  ? __kmalloc+0x1bb/0x1ce
[ 1822.152546]  __kmem_cache_shutdown+0x151/0x28b
[ 1822.153395]  shutdown_cache+0x13/0x144
[ 1822.154126]  kmem_cache_destroy+0x1c0/0x1fb
[ 1822.154669]  SyS_delete_module+0x194/0x244
[ 1822.155199]  ? trace_hardirqs_on_thunk+0x1a/0x1c
[ 1822.155773]  entry_SYSCALL_64_fastpath+0x23/0x9a
[ 1822.156343] RIP: 0033:0x7f929bd38b17
[ 1822.156859] RSP: 002b:00007ffd160e9a98 EFLAGS: 00000202 ORIG_RAX: 00000000000000b0
[ 1822.157728] RAX: ffffffffffffffda RBX: 00005578316ba090 RCX: 00007f929bd38b17
[ 1822.158422] RDX: 00007f929bd9ec60 RSI: 0000000000000800 RDI: 00005578316ba0f0
[ 1822.159114] RBP: 0000000000000003 R08: 00007f929bff5f20 R09: 00007ffd160e8a11
[ 1822.159808] R10: 00007ffd160e9860 R11: 0000000000000202 R12: 00007ffd160e8a80
[ 1822.160513] R13: 0000000000000000 R14: 0000000000000000 R15: 00005578316ba090
[ 1822.161278] INFO: Object 0x000000007645de29 @offset=0
[ 1822.161666] INFO: Object 0x00000000d5df2ab5 @offset=128

Fixes: 30313a3d5794 ("bridge: Handle IFLA_ADDRESS correctly when creating bridge device")
Fixes: 5b8d5429daa0 ("bridge: netlink: register netdevice before executing changelink")
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv4: Fix use-after-free when flushing FIB tables

2018-01-02T19:35:12+00:00

[ Upstream commit b4681c2829e24943aadd1a7bb3a30d41d0a20050 ]

Since commit 0ddcf43d5d4a ("ipv4: FIB Local/MAIN table collapse") the
local table uses the same trie allocated for the main table when custom
rules are not in use.

When a net namespace is dismantled, the main table is flushed and freed
(via an RCU callback) before the local table. In case the callback is
invoked before the local table is iterated, a use-after-free can occur.

Fix this by iterating over the FIB tables in reverse order, so that the
main table is always freed after the local table.

v3: Reworded comment according to Alex's suggestion.
v2: Add a comment to make the fix more explicit per Dave's and Alex's
feedback.

Fixes: 0ddcf43d5d4a ("ipv4: FIB Local/MAIN table collapse")
Signed-off-by: Ido Schimmel 
Reported-by: Fengguang Wu 
Acked-by: Alexander Duyck 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

adding missing rcu_read_unlock in ipxip6_rcv

2018-01-02T19:35:12+00:00

[ Upstream commit 74c4b656c3d92ec4c824ea1a4afd726b7b6568c8 ]

commit 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
introduced new exit point in  ipxip6_rcv. however rcu_read_unlock is
missing there. this diff is fixing this

v1->v2:
 instead of doing rcu_read_unlock in place, we are going to "drop"
 section (to prevent skb leakage)

Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
Signed-off-by: Nikita V. Shirokov 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: Replace use of sockets_allocated with specified macro.

2018-01-02T19:35:12+00:00

[ Upstream commit 8cb38a602478e9f806571f6920b0a3298aabf042 ]

The patch(180d8cd942ce) replaces all uses of struct sock fields'
memory_pressure, memory_allocated, sockets_allocated, and sysctl_mem
to accessor macros. But the sockets_allocated field of sctp sock is
not replaced at all. Then replace it now for unifying the code.

Fixes: 180d8cd942ce ("foundations of per-cgroup memory pressure controlling.")
Cc: Glauber Costa 
Signed-off-by: Tonghao Zhang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman