tipc_wait_for_cond() drops socket lock before going to sleep,
but tsk->group could be freed right after that release_sock().
So we have to re-check and reload tsk->group after it wakes up.

After this patch, tipc_wait_for_cond() returns -ERESTARTSYS when
tsk->group is NULL, instead of continuing with the assumption of
a non-NULL tsk->group.

(It looks like 'dsts' should be re-checked and reloaded too, but
it is a different bug.)

Similar for tipc_send_group_unicast() and tipc_send_group_anycast().

Reported-by: syzbot+10a9db47c3a0e13eb31c@syzkaller.appspotmail.com
Fixes: b7d42635 ("tipc: introduce flow control for group broadcast messages")
Fixes: ee106d7f ("tipc: introduce group anycast messaging")
Fixes: 27bd9ec0 ("tipc: introduce group unicast messaging")
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

While most distributions long ago switched to the iproute2 suite
of utilities, which allow class-e (240.0.0.0/4) address assignment,
distributions relying on busybox, toybox and other forms of
ifconfig cannot assign class-e addresses without this kernel patch.

While CIDR has been obsolete for 2 decades, and a survey of all the
open source code in the world shows the IN_whatever macros are also
obsolete... rather than obsolete CIDR from this ioctl entirely, this
patch merely enables class-e assignment, sanely.
Signed-off-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vr.mifi is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

net/ipv6/ip6mr.c:1845 ip6mr_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
net/ipv6/ip6mr.c:1919 ip6mr_compat_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)

Fix this by sanitizing vr.mifi before using it to index mrt->vif_table'

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The get_mac_address() function is normally inline, but when it is
not, we get a warning that this configuration is broken:

WARNING: vmlinux.o(.text+0x4aff00): Section mismatch in reference from the function w90p910_ether_setup() to the function .init.text:get_mac_address()
The function w90p910_ether_setup() references
the function __init get_mac_address().
This is often because w90p910_ether_setup lacks a __init

Remove the __init to make it always do the right thing.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

The old code always starts from fixed port for VMADDR_PORT_ANY. Sometimes
when VMM crashed, there is still orphaned vsock which is waiting for
close timer, then it could cause connection time out for new started VM
if they are trying to connect to same port with same guest cid since the
new packets could hit that orphaned vsock. We could also fix this by doing
more in vhost_vsock_reset_orphans, but any way, it should be better to start
from a random local port instead of a fixed one.
Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

All previous docks and dongles that have supported this feature use
the RTL8153-AD chip.

RTL8153-BND is a new chip that will be used in upcoming Dell type-C docks.
It should be added to the whitelist of devices to activate MAC address
pass through.

Per confirming with Realtek all devices containing RTL8153-BND should
activate MAC pass through and there won't use pass through bit on efuse
like in RTL8153-AD.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

recalculated send and receive window using linkspeed.
Determine correct value of eck_ok from SYN received and
option configured on local system.
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

corrected macro used in tx path. removed redundant hdrlen
and check for !page in chtls_sendmsg
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

listen fails when more than one tls capable device is
registered. tls_hw_hash is called for each dev which loops
again for each cdev_list causing listen failure. Hence
call chtls_listen_start/stop for specific device than loop over all
devices.
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

HW unhash within mutex for registered tls devices cause sleep
when called from tcp_set_state for TCP_CLOSE. Release lock and
re-acquire after function call with ref count incr/dec.
defined kref and fp release for tls_device to ensure device
is not released outside lock.

BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:748
in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/7
INFO: lockdep is turned off.
CPU: 7 PID: 0 Comm: swapper/7 Tainted: G        W  O
Call Trace:
 <IRQ>
 dump_stack+0x5e/0x8b
 ___might_sleep+0x222/0x260
 __mutex_lock+0x5c/0xa50
 ? vprintk_emit+0x1f3/0x440
 ? kmem_cache_free+0x22d/0x2a0
 ? tls_hw_unhash+0x2f/0x80
 ? printk+0x52/0x6e
 ? tls_hw_unhash+0x2f/0x80
 tls_hw_unhash+0x2f/0x80
 tcp_set_state+0x5f/0x180
 tcp_done+0x2e/0xe0
 tcp_rcv_state_process+0x92c/0xdd3
 ? lock_acquire+0xf5/0x1f0
 ? tcp_v4_rcv+0xa7c/0xbe0
 ? tcp_v4_do_rcv+0x70/0x1e0
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

create_ctx is called from tls_init and tls_hw_prot
hence initialize function pointers in common routine.
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clang warns:

drivers/net/ethernet/apm/xgene/xgene_enet_main.c:33:36: warning:
tentative array definition assumed to have one element
static const struct acpi_device_id xgene_enet_acpi_match[];
                                   ^
1 warning generated.

Both xgene_enet_acpi_match and xgene_enet_of_match are defined before
their uses at the bottom of the file so this is unnecessary. When
CONFIG_ACPI is disabled, ACPI_PTR becomes NULL so xgene_enet_acpi_match
doesn't need to be defined.
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When TIPC_NLA_UDP_REMOTE is an IPv6 mcast address but
TIPC_NLA_UDP_LOCAL is an IPv4 address, a NULL-ptr deref is triggered
as the UDP tunnel sock is initialized to IPv4 or IPv6 sock merely
based on the protocol in local address.

We should just error out when the remote address and local address
have different protocols.

Reported-by: syzbot+eb4da3a20fad2e52555d@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tipc_udp_xmit() drops the packet on error, there is no
need to drop it again.

Fixes: ef20cd4d ("tipc: introduce UDP replicast")
Reported-and-tested-by: syzbot+eae585ba2cc2752d3704@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

lock_sock() must be used in process context to be race-free with
other lock_sock() callers, for example, tipc_release(). Otherwise
using the spinlock directly can't serialize a parallel tipc_release().

As it is blocking, we have to hold the sock refcnt before
rhashtable_walk_stop() and release it after rhashtable_walk_start().

Fixes: 07f6c4bc ("tipc: convert tipc reference table to use generic rhashtable")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

NETLINK_DUMP_STRICT_CHK can be used for all GET requests,
dumps as well as doit handlers.  Replace the DUMP in the
name with GET make that clearer.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The value for OEM_CFG_UPDATE command differs between driver and the
Management firmware (mfw). Fix this gap with adding a reserved field.

Fixes: cac6f691 ("qed: Add support for Unified Fabric Port.")
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mlx5-fixes-2018-12-13

Subject: [pull request][net 0/9] Mellanox, mlx5 fixes 2018-12-13
Saeed Mahameed says:

====================
This series introduces some fixes to the mlx5 core and mlx5e netdevice
driver.

=======
Conflict with net-next: When merged with net-next this series will
cause a moderate conflict:

1) in drivers/net/ethernet/mellanox/mlx5/core/en_tc.c (2 hunks)
Take hunks from net only and just replace *attr->mirror_count to *attr->split_count
1.1) there is one more instance of slow_attr->mirror_count to be replaced
with slow_attr->split_count, it doesn't appear in the conflict, it will
cause a compilation error if left out.
2) in mlx5_ifc.h, take hunks only from net.

Example for the merge resolution can be found at:
https://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux.git/commit/?h=merge/mlx5-fixes&id=48830adf29804d85d77ed8a251d625db0eb5b8a8
branch merge/mlx5-fixes of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
(I simply merged this pull request tag into net-next and resolved the conflict)

I don't know if it's ok with you, but to save your time, you can just:
git pull git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux merge/mlx5-fixes
Into net-next, before your next net merge, and you will have a clean
merge of net into net-next (at least for mlx5 files).
======

Please pull and let me know if there's any problem.

For -stable v4.18
338d615be484 ('net/mlx5e: Cancel DIM work on close SQ')
91f40f9904ad ('net/mlx5e: RX, Verify MPWQE stride size is in range')

For -stable v4.19
c5c7e1c41bbe ('net/mlx5e: Remove unused UDP GSO remaining counter')
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

TXQ SQ closure is followed by closing the corresponding CQ. A pending
DIM work would try to modify the now non-existing CQ.
This would trigger an error:
[85535.835926] mlx5_core 0000:af:00.0: mlx5_cmd_check:769:(pid 124399):
MODIFY_CQ(0x403) op_mod(0x0) failed, status bad resource state(0x9), syndrome (0x1d7771)

Fix by making sure to cancel any pending DIM work before destroying the SQ.

Fixes: cbce4f44 ("net/mlx5e: Enable adaptive-TX moderation")
Signed-off-by: Tal Gilboa <talgi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Remove tx_udp_seg_rem counter from ethtool output, as it is no longer
being updated in the driver's data flow.

Fixes: 3f44899e ("net/mlx5e: Use PARTIAL_GSO for UDP segmentation")
Signed-off-by: Mikhael Goikhman <migo@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Currently, we are deleting offloaded encap flows in case the relevant neigh
becomes unconnected while the encap is valid (a sign that it used to be
connected), or if the curr neigh mac is different from the cached mac
(a sign that the remote side changed their mac).

The 2nd check also applies when the neigh becomes connected on the 1st
time (we start with zero mac). Before the offending commit, the deleting
handler was practically no op, as no flows were offloaded. But since
that commit, we offload neigh-less encap flows to slow path.

Under mirroring scheme, we go into the delete handler, attempt to unoffload a
mirror rule which was never set (as we were offloading to slow path) and crash.

Fix that by calling the delete handler only when the encap is valid,
which covers both cases mentioned above.

Fixes: 5dbe906f ('net/mlx5e: Use a slow path rule instead if vxlan neighbour isn't available')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

When a neighbour is resolved, we delete the goto slow path rule from HW.

The eswitch flow attributes where not properly initialized on that case,
hence we mess up the eswitch refcounts for chain zero (the default one).

Fix that along with making sure to use semicolons and not commas on that code;

Fixes: 5dbe906f ('net/mlx5e: Use a slow path rule instead if vxlan neighbour isn't available')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Just a leftover which was wrongly left there, remove it while spawning
a message to suggest firmware upgrade.

Fixes: bf07aa73 ('net/mlx5e: Support offloading tc priorities and chains for eswitch flows')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Currently we are not supporting this and not err-ing on that either.

For now, just err if asked to do that.

Fixes: bf07aa73 ('net/mlx5e: Support offloading tc priorities and chains for eswitch flows')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reported-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Eli Britstein <elibr@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Add check of MPWQE stride size is within range supported by HW. In case
calculated MPWQE stride size exceed range, linear SKB can't be used and
we should use non linear MPWQE instead.

Fixes: 619a8f2a ("net/mlx5e: Use linear SKB in Striding RQ")
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

The default amount of channels a representor opens was erroneously
changed from one to the maximum amount of channels, restore to its
intended value.

Fixes: 779d986d ("net/mlx5e: Do not ignore netdevice TX/RX queues number")
Signed-off-by: Gavi Teitz <gavi@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

The cap bits locations for the fdb caps of multi path to table (used for
local mirroring) and multi encap (used for prio/chains) were wrongly used
in swapped locations. This went unnoted so far b/c we tested the offending
patch with CX5 FW that supports both of them. On different environments where
not both caps are supported, we will be messed up, fix that.

Fixes: b9aa0ba1 ('net/mlx5: Add cap bits for multi fdb encap')
Signed-off-by: Vu Pham <vu@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Tested-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Jason Wang says:

====================
Fix various issue of vhost

This series tries to fix various issues of vhost:

- Patch 1 adds a missing write barrier between used idx updating and
  logging.
- Patch 2-3 brings back the protection of device IOTLB through vq
  mutex, this fixes possible use after free in device IOTLB entries.

Please consider them for -stable.

Changes from V2:
- drop dirty page fix and make it for net-next
Changes from V1:
- silent compiler warning for 32bit.
- use mutex_trylock() on slowpath instead of mutex_lock() even on fast
  path.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This reverts commit 78139c94. We don't
protect device IOTLB with vq mutex, which will lead e.g use after free
for device IOTLB entries. And since we've switched to use
mutex_trylock() in previous patch, it's safe to revert it without
having deadlock.

Fixes: commit 78139c94 ("net: vhost: lock the vqs one by one")
Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We used to hold the mutex of paired virtqueue in
vhost_net_busy_poll(). But this will results an inconsistent lock
order which may cause deadlock if we try to bring back the protection
of device IOTLB with vq mutex that requires to hold mutex of all
virtqueues at the same time.

Fix this simply by switching to use mutex_trylock(), when fail just
skip the busy polling. This can happen when device IOTLB is under
updating which should be rare.

Fixes: commit 78139c94 ("net: vhost: lock the vqs one by one")
Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We miss a write barrier that guarantees used idx is updated and seen
before log. This will let userspace sync and copy used ring before
used idx is update. Fix this by adding a barrier before log_write().

Fixes: 8dd014ad ("vhost-net: mergeable buffers support")
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Fixes 2018-12-12

This series contains fixes to i40e and ixgbe.

Stefan Assmann fixes an issue created by a previous fix, where
ether_addr_copy() was moved to avoid a race but did not take into
account that it alters the MAC address being handed to
i40e_del_mac_filter().

Michał Mirosław provides 2 fixes for i40e, first resolves issues in the
hardware VLAN offload where VLAN.TCI equal to 0 was being dropped and a
race between disabling VLAN receive feature in hardware and processing
the receive queue, where packets could have their VLAN information
dropped.

Ross Lagerwall fixes a racy condition during a ixgbe VF reset, where
writing the register to issue a reset and sending the reset message via
the mailbox API could result of the mailbox memory getting cleared
during the reset before the message gets successfully sent which results
in a VF driver malfunction.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Fix warnings suspicious rcu usage when handling base chain
   statistics, from Taehee Yoo.

2) Refetch pointer to tcp header from nf_ct_sack_adjust() since
   skb_make_writable() may reallocate data area, reported by Google
   folks patch from Florian.

3) Incorrect netlink nest end after previous cancellation from error
   path in ipset, from Pan Bian.

4) Use dst_hold_safe() from nf_xfrm_me_harder(), from Florian.

5) Use rb_link_node_rcu() for rcu-protected rbtree node in
   nf_conncount, from Taehee Yoo.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Sudarsana Reddy Kalluru says:

====================
bnx2x: Fix series

The patch series addresses few important issues in the bnx2x driver.
Please consider applying it 'net' tree.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Driver sends update-SVID ramrod in the MFW notification path.
If there is a pending ramrod, driver doesn't retry the command
and storm firmware will never be updated with the SVID value.
The patch adds changes to send update-svid ramrod in process context with
retry/poll flags set.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There will be only one PHC clock per port. PTP should be enabled only on
one PF per port. The change enables PTP functionality on the PF that
initializes the port. The change is useful in multi-function modes e.g.,
NPAR where a port can have more than one PF.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vlans are not getting removed when drivers are unloaded. The recent storm
firmware versions had added safeguards against re-configuring an already
configured vlan. As a result, PF inner reload flows (e.g., mtu change)
might trigger an assertion.
This change is going to remove vlans (same as we do for MACs) when doing
a chip cleanup during unload.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On some customer setups it was observed that shmem contains a non-zero fip
MAC for 57711 which would lead to enabling of SW FCoE.
Add a software workaround to clear the bad fip mac address if no FCoE
connections are supported.
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rbnode in insert_tree() is rcu protected pointer.
So, in order to handle this pointer, _rcu function should be used.
rb_link_node_rcu() is a rcu version of rb_link_node().

Fixes: 34848d5c ("netfilter: nf_conncount: Split insert and traversal")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

The dst entry might already have a zero refcount, waiting on rcu list
to be free'd.  Using dst_hold() transitions its reference count to 1, and
next dst release will try to free it again -- resulting in a double free:

  WARNING: CPU: 1 PID: 0 at include/net/dst.h:239 nf_xfrm_me_harder+0xe7/0x130 [nf_nat]
  RIP: 0010:nf_xfrm_me_harder+0xe7/0x130 [nf_nat]
  Code: 48 8b 5c 24 60 65 48 33 1c 25 28 00 00 00 75 53 48 83 c4 68 5b 5d 41 5c c3 85 c0 74 0d 8d 48 01 f0 0f b1 0a 74 86 85 c0 75 f3 <0f> 0b e9 7b ff ff ff 29 c6 31 d2 b9 20 00 48 00 4c 89 e7 e8 31 27
  Call Trace:
  nf_nat_ipv4_out+0x78/0x90 [nf_nat_ipv4]
  nf_hook_slow+0x36/0xd0
  ip_output+0x9f/0xd0
  ip_forward+0x328/0x440
  ip_rcv+0x8a/0xb0

Use dst_hold_safe instead and bail out if we cannot take a reference.

Fixes: a4c2fd7f ("net: remove DST_NOCACHE flag")
Reported-by: Martin Zaharinov <micron10@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>