linux-stable.git/net/core, branch v4.4.52

net: use a work queue to defer net_disable_timestamp() work

2017-02-18T15:39:26+00:00

[ Upstream commit 5fa8bbda38c668e56b0c6cdecced2eac2fe36dec ]

Dmitry reported a warning [1] showing that we were calling
net_disable_timestamp() -> static_key_slow_dec() from a non
process context.

Grabbing a mutex while holding a spinlock or rcu_read_lock()
is not allowed.

As Cong suggested, we now use a work queue.

It is possible netstamp_clear() exits while netstamp_needed_deferred
is not zero, but it is probably not worth trying to do better than that.

netstamp_needed_deferred atomic tracks the exact number of deferred
decrements.

[1]
[ INFO: suspicious RCU usage. ]
4.10.0-rc5+ #192 Not tainted
-------------------------------
./include/linux/rcupdate.h:561 Illegal context switch in RCU read-side
critical section!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 0
2 locks held by syz-executor14/23111:
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: [] lock_sock
include/net/sock.h:1454 [inline]
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: []
rawv6_sendmsg+0x1e65/0x3ec0 net/ipv6/raw.c:919
 #1:  (rcu_read_lock){......}, at: [] nf_hook
include/linux/netfilter.h:201 [inline]
 #1:  (rcu_read_lock){......}, at: []
__ip6_local_out+0x258/0x840 net/ipv6/output_core.c:160

stack backtrace:
CPU: 2 PID: 23111 Comm: syz-executor14 Not tainted 4.10.0-rc5+ #192
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:15 [inline]
 dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
 lockdep_rcu_suspicious+0x139/0x180 kernel/locking/lockdep.c:4452
 rcu_preempt_sleep_check include/linux/rcupdate.h:560 [inline]
 ___might_sleep+0x560/0x650 kernel/sched/core.c:7748
 __might_sleep+0x95/0x1a0 kernel/sched/core.c:7739
 mutex_lock_nested+0x24f/0x1730 kernel/locking/mutex.c:752
 atomic_dec_and_mutex_lock+0x119/0x160 kernel/locking/mutex.c:1060
 __static_key_slow_dec+0x7a/0x1e0 kernel/jump_label.c:149
 static_key_slow_dec+0x51/0x90 kernel/jump_label.c:174
 net_disable_timestamp+0x3b/0x50 net/core/dev.c:1728
 sock_disable_timestamp+0x98/0xc0 net/core/sock.c:403
 __sk_destruct+0x27d/0x6b0 net/core/sock.c:1441
 sk_destruct+0x47/0x80 net/core/sock.c:1460
 __sk_free+0x57/0x230 net/core/sock.c:1468
 sock_wfree+0xae/0x120 net/core/sock.c:1645
 skb_release_head_state+0xfc/0x200 net/core/skbuff.c:655
 skb_release_all+0x15/0x60 net/core/skbuff.c:668
 __kfree_skb+0x15/0x20 net/core/skbuff.c:684
 kfree_skb+0x16e/0x4c0 net/core/skbuff.c:705
 inet_frag_destroy+0x121/0x290 net/ipv4/inet_fragment.c:304
 inet_frag_put include/net/inet_frag.h:133 [inline]
 nf_ct_frag6_gather+0x1106/0x3840
net/ipv6/netfilter/nf_conntrack_reasm.c:617
 ipv6_defrag+0x1be/0x2b0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:68
 nf_hook_entry_hookfn include/linux/netfilter.h:102 [inline]
 nf_hook_slow+0xc3/0x290 net/netfilter/core.c:310
 nf_hook include/linux/netfilter.h:212 [inline]
 __ip6_local_out+0x489/0x840 net/ipv6/output_core.c:160
 ip6_local_out+0x2d/0x170 net/ipv6/output_core.c:170
 ip6_send_skb+0xa1/0x340 net/ipv6/ip6_output.c:1722
 ip6_push_pending_frames+0xb3/0xe0 net/ipv6/ip6_output.c:1742
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x2d1a/0x3ec0 net/ipv6/raw.c:927
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744
 sock_sendmsg_nosec net/socket.c:635 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:645
 sock_write_iter+0x326/0x600 net/socket.c:848
 do_iter_readv_writev+0x2e3/0x5b0 fs/read_write.c:695
 do_readv_writev+0x42c/0x9b0 fs/read_write.c:872
 vfs_writev+0x87/0xc0 fs/read_write.c:911
 do_writev+0x110/0x2c0 fs/read_write.c:944
 SYSC_writev fs/read_write.c:1017 [inline]
 SyS_writev+0x27/0x30 fs/read_write.c:1014
 entry_SYSCALL_64_fastpath+0x1f/0xc2
RIP: 0033:0x445559
RSP: 002b:00007f6f46fceb58 EFLAGS: 00000292 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000445559
RDX: 0000000000000001 RSI: 0000000020f1eff0 RDI: 0000000000000005
RBP: 00000000006e19c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000700000
R13: 0000000020f59000 R14: 0000000000000015 R15: 0000000000020400
BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:752
in_atomic(): 1, irqs_disabled(): 0, pid: 23111, name: syz-executor14
INFO: lockdep is turned off.
CPU: 2 PID: 23111 Comm: syz-executor14 Not tainted 4.10.0-rc5+ #192
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:15 [inline]
 dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
 ___might_sleep+0x47e/0x650 kernel/sched/core.c:7780
 __might_sleep+0x95/0x1a0 kernel/sched/core.c:7739
 mutex_lock_nested+0x24f/0x1730 kernel/locking/mutex.c:752
 atomic_dec_and_mutex_lock+0x119/0x160 kernel/locking/mutex.c:1060
 __static_key_slow_dec+0x7a/0x1e0 kernel/jump_label.c:149
 static_key_slow_dec+0x51/0x90 kernel/jump_label.c:174
 net_disable_timestamp+0x3b/0x50 net/core/dev.c:1728
 sock_disable_timestamp+0x98/0xc0 net/core/sock.c:403
 __sk_destruct+0x27d/0x6b0 net/core/sock.c:1441
 sk_destruct+0x47/0x80 net/core/sock.c:1460
 __sk_free+0x57/0x230 net/core/sock.c:1468
 sock_wfree+0xae/0x120 net/core/sock.c:1645
 skb_release_head_state+0xfc/0x200 net/core/skbuff.c:655
 skb_release_all+0x15/0x60 net/core/skbuff.c:668
 __kfree_skb+0x15/0x20 net/core/skbuff.c:684
 kfree_skb+0x16e/0x4c0 net/core/skbuff.c:705
 inet_frag_destroy+0x121/0x290 net/ipv4/inet_fragment.c:304
 inet_frag_put include/net/inet_frag.h:133 [inline]
 nf_ct_frag6_gather+0x1106/0x3840
net/ipv6/netfilter/nf_conntrack_reasm.c:617
 ipv6_defrag+0x1be/0x2b0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:68
 nf_hook_entry_hookfn include/linux/netfilter.h:102 [inline]
 nf_hook_slow+0xc3/0x290 net/netfilter/core.c:310
 nf_hook include/linux/netfilter.h:212 [inline]
 __ip6_local_out+0x489/0x840 net/ipv6/output_core.c:160
 ip6_local_out+0x2d/0x170 net/ipv6/output_core.c:170
 ip6_send_skb+0xa1/0x340 net/ipv6/ip6_output.c:1722
 ip6_push_pending_frames+0xb3/0xe0 net/ipv6/ip6_output.c:1742
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x2d1a/0x3ec0 net/ipv6/raw.c:927
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744
 sock_sendmsg_nosec net/socket.c:635 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:645
 sock_write_iter+0x326/0x600 net/socket.c:848
 do_iter_readv_writev+0x2e3/0x5b0 fs/read_write.c:695
 do_readv_writev+0x42c/0x9b0 fs/read_write.c:872
 vfs_writev+0x87/0xc0 fs/read_write.c:911
 do_writev+0x110/0x2c0 fs/read_write.c:944
 SYSC_writev fs/read_write.c:1017 [inline]
 SyS_writev+0x27/0x30 fs/read_write.c:1014
 entry_SYSCALL_64_fastpath+0x1f/0xc2
RIP: 0033:0x445559

Fixes: b90e5794c5bd ("net: dont call jump_label_dec from irq context")
Suggested-by: Cong Wang 
Reported-by: Dmitry Vyukov 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: fix harmonize_features() vs NETIF_F_HIGHDMA

2017-02-04T08:45:09+00:00

[ Upstream commit 7be2c82cfd5d28d7adb66821a992604eb6dd112e ]

Ashizuka reported a highmem oddity and sent a patch for freescale
fec driver.

But the problem root cause is that core networking stack
must ensure no skb with highmem fragment is ever sent through
a device that does not assert NETIF_F_HIGHDMA in its features.

We need to call illegal_highdma() from harmonize_features()
regardless of CSUM checks.

Fixes: ec5f06156423 ("net: Kill link between CSUM and SG features.")
Signed-off-by: Eric Dumazet 
Cc: Pravin Shelar 
Reported-by: "Ashizuka, Yuusuke" 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gro: use min_t() in skb_gro_reset_offset()

2017-01-15T12:41:35+00:00

[ Upstream commit 7cfd5fd5a9813f1430290d20c0fead9b4582a307 ]

On 32bit arches, (skb->end - skb->data) is not 'unsigned int',
so we shall use min_t() instead of min() to avoid a compiler error.

Fixes: 1272ce87fa01 ("gro: Enter slow-path if there is no tailroom")
Reported-by: kernel test robot 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

gro: Enter slow-path if there is no tailroom

2017-01-15T12:41:35+00:00

[ Upstream commit 1272ce87fa017ca4cf32920764d879656b7a005a ]

The GRO path has a fast-path where we avoid calling pskb_may_pull
and pskb_expand by directly accessing frag0.  However, this should
only be done if we have enough tailroom in the skb as otherwise
we'll have to expand it later anyway.

This patch adds the check by capping frag0_len with the skb tailroom.

Fixes: cb18978cbf45 ("gro: Open-code final pskb_may_pull")
Reported-by: Slava Shwartsman 
Signed-off-by: Herbert Xu 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

drop_monitor: consider inserted data in genlmsg_end

2017-01-15T12:41:35+00:00

[ Upstream commit 3b48ab2248e61408910e792fe84d6ec466084c1a ]

Final nlmsg_len field update must reflect inserted net_dm_drop_point
data.

This patch depends on previous patch:
"drop_monitor: add missing call to genlmsg_end"

Signed-off-by: Reiter Wolfgang 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

drop_monitor: add missing call to genlmsg_end

2017-01-15T12:41:35+00:00

[ Upstream commit 4200462d88f47f3759bdf4705f87e207b0f5b2e4 ]

Update nlmsg_len field with genlmsg_end to enable userspace processing
using nlmsg_next helper. Also adds error handling.

Signed-off-by: Reiter Wolfgang 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: avoid signed overflows for SO_{SND|RCV}BUFFORCE

2016-12-10T18:07:24+00:00

[ Upstream commit b98b0bc8c431e3ceb4b26b0dfc8db509518fb290 ]

CAP_NET_ADMIN users should not be allowed to set negative
sk_sndbuf or sk_rcvbuf values, as it can lead to various memory
corruptions, crashes, OOM...

Note that before commit 82981930125a ("net: cleanups in
sock_setsockopt()"), the bug was even more serious, since SO_SNDBUF
and SO_RCVBUF were vulnerable.

This needs to be backported to all known linux kernels.

Again, many thanks to syzkaller team for discovering this gem.

Signed-off-by: Eric Dumazet 
Reported-by: Andrey Konovalov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: fix FDB size computation

2016-12-10T18:07:22+00:00

[ Upstream commit f82ef3e10a870acc19fa04f80ef5877eaa26f41e ]

Add missing NDA_VLAN attribute's size.

Fixes: 1e53d5bb8878 ("net: Pass VLAN ID to rtnl_fdb_notify.")
Signed-off-by: Sabrina Dubroca 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: check dead netns for peernet2id_alloc()

2016-12-10T18:07:22+00:00

[ Upstream commit cfc44a4d147ea605d66ccb917cc24467d15ff867 ]

Andrei reports we still allocate netns ID from idr after we destroy
it in cleanup_net().

cleanup_net():
  ...
  idr_destroy(&net->netns_ids);
  ...
  list_for_each_entry_reverse(ops, &pernet_list, list)
    ops_exit_list(ops, &net_exit_list);
      -> rollback_registered_many()
        -> rtmsg_ifinfo_build_skb()
         -> rtnl_fill_ifinfo()
           -> peernet2id_alloc()

After that point we should not even access net->netns_ids, we
should check the death of the current netns as early as we can in
peernet2id_alloc().

For net-next we can consider to avoid sending rtmsg totally,
it is a good optimization for netns teardown path.

Fixes: 0c7aecd4bde4 ("netns: add rtnl cmd to add and get peer netns ids")
Reported-by: Andrei Vagin 
Cc: Nicolas Dichtel 
Signed-off-by: Cong Wang 
Acked-by: Andrei Vagin 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

flow_dissect: call init_default_flow_dissectors() earlier

2016-12-02T08:09:02+00:00

commit c9b8af1330198ae241cd545e1f040019010d44d9 upstream.

Andre Noll reported panics after my recent fix (commit 34fad54c2537
"net: __skb_flow_dissect() must cap its return value")

After some more headaches, Alexander root caused the problem to
init_default_flow_dissectors() being called too late, in case
a network driver like IGB is not a module and receives DHCP message
very early.

Fix is to call init_default_flow_dissectors() much earlier,
as it is a core infrastructure and does not depend on another
kernel service.

Fixes: 06635a35d13d4 ("flow_dissect: use programable dissector in skb_flow_dissect and friends")
Signed-off-by: Eric Dumazet 
Reported-by: Andre Noll 
Diagnosed-by: Alexander Duyck 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman