linux-stable.git/net/core, branch linux-4.11.y

net: core: Fix slab-out-of-bounds in netdev_stats_to_stats64

2017-07-21T05:00:07+00:00

[ Upstream commit 9af9959e142c274f4a30fefb71d97d2b028b337f ]

commit 9256645af098 ("net/core: relax BUILD_BUG_ON in
netdev_stats_to_stats64") made an attempt to read beyond
the size of the source a possibility.

Fix to only copy src size to dest. As dest might be bigger than src.

 ==================================================================
 BUG: KASAN: slab-out-of-bounds in netdev_stats_to_stats64+0xe/0x30 at addr ffff8801be248b20
 Read of size 192 by task VBoxNetAdpCtl/6734
 CPU: 1 PID: 6734 Comm: VBoxNetAdpCtl Tainted: G           O    4.11.4prahal+intel+ #118
 Hardware name: LENOVO 20CDCTO1WW/20CDCTO1WW, BIOS GQET52WW (1.32 ) 05/04/2017
 Call Trace:
  dump_stack+0x63/0x86
  kasan_object_err+0x1c/0x70
  kasan_report+0x270/0x520
  ? netdev_stats_to_stats64+0xe/0x30
  ? sched_clock_cpu+0x1b/0x190
  ? __module_address+0x3e/0x3b0
  ? unwind_next_frame+0x1ea/0xb00
  check_memory_region+0x13c/0x1a0
  memcpy+0x23/0x50
  netdev_stats_to_stats64+0xe/0x30
  dev_get_stats+0x1b9/0x230
  rtnl_fill_stats+0x44/0xc00
  ? nla_put+0xc6/0x130
  rtnl_fill_ifinfo+0xe9e/0x3700
  ? rtnl_fill_vfinfo+0xde0/0xde0
  ? sched_clock+0x9/0x10
  ? sched_clock+0x9/0x10
  ? sched_clock_local+0x120/0x130
  ? __module_address+0x3e/0x3b0
  ? unwind_next_frame+0x1ea/0xb00
  ? sched_clock+0x9/0x10
  ? sched_clock+0x9/0x10
  ? sched_clock_cpu+0x1b/0x190
  ? VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? depot_save_stack+0x1d8/0x4a0
  ? depot_save_stack+0x34f/0x4a0
  ? depot_save_stack+0x34f/0x4a0
  ? save_stack+0xb1/0xd0
  ? save_stack_trace+0x16/0x20
  ? save_stack+0x46/0xd0
  ? kasan_slab_alloc+0x12/0x20
  ? __kmalloc_node_track_caller+0x10d/0x350
  ? __kmalloc_reserve.isra.36+0x2c/0xc0
  ? __alloc_skb+0xd0/0x560
  ? rtmsg_ifinfo_build_skb+0x61/0x120
  ? rtmsg_ifinfo.part.25+0x16/0xb0
  ? rtmsg_ifinfo+0x47/0x70
  ? register_netdev+0x15/0x30
  ? vboxNetAdpOsCreate+0xc0/0x1c0 [vboxnetadp]
  ? vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  ? VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? do_vfs_ioctl+0x17f/0xff0
  ? SyS_ioctl+0x74/0x80
  ? do_syscall_64+0x182/0x390
  ? __alloc_skb+0xd0/0x560
  ? __alloc_skb+0xd0/0x560
  ? save_stack_trace+0x16/0x20
  ? init_object+0x64/0xa0
  ? ___slab_alloc+0x1ae/0x5c0
  ? ___slab_alloc+0x1ae/0x5c0
  ? __alloc_skb+0xd0/0x560
  ? sched_clock+0x9/0x10
  ? kasan_unpoison_shadow+0x35/0x50
  ? kasan_kmalloc+0xad/0xe0
  ? __kmalloc_node_track_caller+0x246/0x350
  ? __alloc_skb+0xd0/0x560
  ? kasan_unpoison_shadow+0x35/0x50
  ? memset+0x31/0x40
  ? __alloc_skb+0x31f/0x560
  ? napi_consume_skb+0x320/0x320
  ? br_get_link_af_size_filtered+0xb7/0x120 [bridge]
  ? if_nlmsg_size+0x440/0x630
  rtmsg_ifinfo_build_skb+0x83/0x120
  rtmsg_ifinfo.part.25+0x16/0xb0
  rtmsg_ifinfo+0x47/0x70
  register_netdevice+0xa2b/0xe50
  ? __kmalloc+0x171/0x2d0
  ? netdev_change_features+0x80/0x80
  register_netdev+0x15/0x30
  vboxNetAdpOsCreate+0xc0/0x1c0 [vboxnetadp]
  vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  ? vboxNetAdpComposeMACAddress+0x1d0/0x1d0 [vboxnetadp]
  ? kasan_check_write+0x14/0x20
  VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  ? VBoxNetAdpLinuxOpen+0x20/0x20 [vboxnetadp]
  ? lock_acquire+0x11c/0x270
  ? __audit_syscall_entry+0x2fb/0x660
  do_vfs_ioctl+0x17f/0xff0
  ? __audit_syscall_entry+0x2fb/0x660
  ? ioctl_preallocate+0x1d0/0x1d0
  ? __audit_syscall_entry+0x2fb/0x660
  ? kmem_cache_free+0xb2/0x250
  ? syscall_trace_enter+0x537/0xd00
  ? exit_to_usermode_loop+0x100/0x100
  SyS_ioctl+0x74/0x80
  ? do_sys_open+0x350/0x350
  ? do_vfs_ioctl+0xff0/0xff0
  do_syscall_64+0x182/0x390
  entry_SYSCALL64_slow_path+0x25/0x25
 RIP: 0033:0x7f7e39a1ae07
 RSP: 002b:00007ffc6f04c6d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
 RAX: ffffffffffffffda RBX: 00007ffc6f04c730 RCX: 00007f7e39a1ae07
 RDX: 00007ffc6f04c730 RSI: 00000000c0207601 RDI: 0000000000000007
 RBP: 00007ffc6f04c700 R08: 00007ffc6f04c780 R09: 0000000000000008
 R10: 0000000000000541 R11: 0000000000000206 R12: 0000000000000007
 R13: 00000000c0207601 R14: 00007ffc6f04c730 R15: 0000000000000012
 Object at ffff8801be248008, in cache kmalloc-4096 size: 4096
 Allocated:
 PID = 6734
  save_stack_trace+0x16/0x20
  save_stack+0x46/0xd0
  kasan_kmalloc+0xad/0xe0
  __kmalloc+0x171/0x2d0
  alloc_netdev_mqs+0x8a7/0xbe0
  vboxNetAdpOsCreate+0x65/0x1c0 [vboxnetadp]
  vboxNetAdpCreate+0x210/0x400 [vboxnetadp]
  VBoxNetAdpLinuxIOCtlUnlocked+0x14b/0x280 [vboxnetadp]
  do_vfs_ioctl+0x17f/0xff0
  SyS_ioctl+0x74/0x80
  do_syscall_64+0x182/0x390
  return_from_SYSCALL_64+0x0/0x6a
 Freed:
 PID = 5600
  save_stack_trace+0x16/0x20
  save_stack+0x46/0xd0
  kasan_slab_free+0x73/0xc0
  kfree+0xe4/0x220
  kvfree+0x25/0x30
  single_release+0x74/0xb0
  __fput+0x265/0x6b0
  ____fput+0x9/0x10
  task_work_run+0xd5/0x150
  exit_to_usermode_loop+0xe2/0x100
  do_syscall_64+0x26c/0x390
  return_from_SYSCALL_64+0x0/0x6a
 Memory state around the buggy address:
  ffff8801be248a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff8801be248b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 >ffff8801be248b80: 00 00 00 00 00 00 00 00 00 00 00 07 fc fc fc fc
                                                     ^
  ffff8801be248c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff8801be248c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ==================================================================

Signed-off-by: Alban Browaeys 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: handle NAPI_GRO_FREE_STOLEN_HEAD case also in napi_frags_finish()

2017-07-21T05:00:06+00:00

[ Upstream commit e44699d2c28067f69698ccb68dd3ddeacfebc434 ]

Recently I started seeing warnings about pages with refcount -1. The
problem was traced to packets being reused after their head was merged into
a GRO packet by skb_gro_receive(). While bisecting the issue pointed to
commit c21b48cc1bbf ("net: adjust skb->truesize in ___pskb_trim()") and
I have never seen it on a kernel with it reverted, I believe the real
problem appeared earlier when the option to merge head frag in GRO was
implemented.

Handling NAPI_GRO_FREE_STOLEN_HEAD state was only added to GRO_MERGED_FREE
branch of napi_skb_finish() so that if the driver uses napi_gro_frags()
and head is merged (which in my case happens after the skb_condense()
call added by the commit mentioned above), the skb is reused including the
head that has been merged. As a result, we release the page reference
twice and eventually end up with negative page refcount.

To fix the problem, handle NAPI_GRO_FREE_STOLEN_HEAD in napi_frags_finish()
the same way it's done in napi_skb_finish().

Fixes: d7e8883cfcf4 ("net: make GRO aware of skb->head_frag")
Signed-off-by: Michal Kubecek 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: prevent sign extension in dev_get_stats()

2017-07-21T05:00:05+00:00

[ Upstream commit 6f64ec74515925cced6df4571638b5a099a49aae ]

Similar to the fix provided by Dominik Heidler in commit
9b3dc0a17d73 ("l2tp: cast l2tp traffic counter to unsigned")
we need to take care of 32bit kernels in dev_get_stats().

When using atomic_long_read(), we add a 'long' to u64 and
might misinterpret high order bit, unless we cast to unsigned.

Fixes: caf586e5f23ce ("net: add a core netdev->rx_dropped counter")
Fixes: 015f0688f57ca ("net: net: add a core netdev->tx_dropped counter")
Fixes: 6e7333d315a76 ("net: add rx_nohandler stat counter")
Signed-off-by: Eric Dumazet 
Cc: Jarod Wilson 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

rtnetlink: add IFLA_GROUP to ifla_policy

2017-07-05T12:41:37+00:00

[ Upstream commit db833d40ad3263b2ee3b59a1ba168bb3cfed8137 ]

Network interface groups support added while ago, however
there is no IFLA_GROUP attribute description in policy
and netlink message size calculations until now.

Add IFLA_GROUP attribute to the policy.

Fixes: cbda10fa97d7 ("net_device: add support for network device groups")
Signed-off-by: Serhey Popovych 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Fix an intermittent pr_emerg warning about lo becoming free.

2017-07-05T12:41:35+00:00

[ Upstream commit f186ce61bb8235d80068c390dc2aad7ca427a4c2 ]

It looks like this:

Message from syslogd@flamingo at Apr 26 00:45:00 ...
 kernel:unregister_netdevice: waiting for lo to become free. Usage count = 4

They seem to coincide with net namespace teardown.

The message is emitted by netdev_wait_allrefs().

Forced a kdump in netdev_run_todo, but found that the refcount on the lo
device was already 0 at the time we got to the panic.

Used bcc to check the blocking in netdev_run_todo.  The only places
where we're off cpu there are in the rcu_barrier() and msleep() calls.
That behavior is expected.  The msleep time coincides with the amount of
time we spend waiting for the refcount to reach zero; the rcu_barrier()
wait times are not excessive.

After looking through the list of callbacks that the netdevice notifiers
invoke in this path, it appears that the dst_dev_event is the most
interesting.  The dst_ifdown path places a hold on the loopback_dev as
part of releasing the dev associated with the original dst cache entry.
Most of our notifier callbacks are straight-forward, but this one a)
looks complex, and b) places a hold on the network interface in
question.

I constructed a new bcc script that watches various events in the
liftime of a dst cache entry.  Note that dst_ifdown will take a hold on
the loopback device until the invalidated dst entry gets freed.

[      __dst_free] on DST: ffff883ccabb7900 IF tap1008300eth0 invoked at 1282115677036183
    __dst_free
    rcu_nocb_kthread
    kthread
    ret_from_fork
Acked-by: Eric Dumazet 

Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Zero ifla_vf_info in rtnl_fill_vfinfo()

2017-07-05T12:41:34+00:00

[ Upstream commit 0eed9cf58446b28b233388b7f224cbca268b6986 ]

Some of the structure's fields are not initialized by the
rtnetlink. If driver doesn't set those in ndo_get_vf_config(),
they'd leak memory to user.

Signed-off-by: Yuval Mintz 
CC: Michal Schmidt 
Reviewed-by: Greg Rose 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Fix inconsistent teardown and release of private netdev state.

2017-07-05T12:41:34+00:00

[ Upstream commit cf124db566e6b036b8bcbe8decbed740bdfac8c6 ]

Network devices can allocate reasources and private memory using
netdev_ops->ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops->ndo_uninit() or netdev->destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev->destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
it is not able to invoke netdev->destructor().

This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev->destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().

netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().

Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: don't call strlen on non-terminated string in dev_set_alias()

2017-07-05T12:41:33+00:00

[ Upstream commit c28294b941232931fbd714099798eb7aa7e865d7 ]

KMSAN reported a use of uninitialized memory in dev_set_alias(),
which was caused by calling strlcpy() (which in turn called strlen())
on the user-supplied non-terminated string.

Signed-off-by: Alexander Potapenko 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sock: reset sk_err when the error queue is empty

2017-06-14T13:07:34+00:00

[ Upstream commit 38b257938ac6655d0d6333743303231b9c465ec1 ]

Prior to f5f99309fa74 (sock: do not set sk_err in
sock_dequeue_err_skb), sk_err was reset to the error of
the skb on the head of the error queue.

Applications, most notably ping, are relying on this
behavior to reset sk_err for ICMP packets.

Set sk_err to the ICMP error when there is an ICMP packet
at the head of the error queue.

Fixes: f5f99309fa74 (sock: do not set sk_err in sock_dequeue_err_skb)
Reported-by: Cyril Hrubis 
Tested-by: Cyril Hrubis 
Signed-off-by: Soheil Hassas Yeganeh 
Signed-off-by: Eric Dumazet 
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bpf: add bpf_clone_redirect to bpf_helper_changes_pkt_data

2017-06-07T10:10:05+00:00

[ Upstream commit 41703a731066fde79c3e5ccf3391cf77a98aeda5 ]

The bpf_clone_redirect() still needs to be listed in
bpf_helper_changes_pkt_data() since we call into
bpf_try_make_head_writable() from there, thus we need
to invalidate prior pkt regs as well.

Fixes: 36bbef52c7eb ("bpf: direct packet write and access for helpers for clsact progs")
Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman