There's no need to verify that cfg->ifname is unique at this point.
register_netdev() will return -EEXIST if asked to create a device with
a name that's alrealy in use.
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since netif_carrier_on() will do nothing if device's carrier is already
on, so it's unnecessary to do carrier status check.

It's the same for netif_carrier_off().
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch updates the comment for netif_dormant() function to reflect
the intended usage.
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add option to xdp1 and xdp_tx_iptunnel to insert xdp program in
SKB_MODE:
 - update set_link_xdp_fd to take a flags argument that is added to the
   RTM_SETLINK message

 - Add -S option to xdp1 and xdp_tx_iptunnel user code. When passed in
   XDP_FLAGS_SKB_MODE is set in the flags arg passed to set_link_xdp_fd
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When max_size is not set or if it set to a sufficiently large
value, the nelems counter can overflow.  This would cause havoc
with the automatic shrinking as it would then attempt to fit a
huge number of entries into a tiny hash table.

This patch fixes this by adding max_elems to struct rhashtable
to cap the number of elements.  This is set to 2^31 as nelems is
not a precise count.  This is sufficiently smaller than UINT_MAX
that it should be safe.

When max_size is set max_elems will be lowered to at most twice
max_size as is the status quo.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I wrongly assumed tp->tcp_mstamp was up to date at the time
tcp_rack_reo_timeout() was called.

It is not true, since we only update tcp->tcp_mstamp when receiving
a packet (as initially done in commit 69e996c5 ("tcp: add
tp->tcp_mstamp field")

tcp_rack_reo_timeout() being called by a timer and not an incoming
packet, we need to refresh tp->tcp_mstamp

Fixes: 7c1c7308 ("tcp: do not pass timestamp to tcp_rack_detect_loss()")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull sparc fixes from David Miller:
 "I didn't want the release to go out without the statx system call
  properly hooked up"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Update syscall tables.
  sparc64: Fill in rest of HAVE_REGS_AND_STACK_ACCESS_API

With the new statx() syscall, the following both allow the attributes of
the file attached to a file descriptor to be retrieved:

	statx(dfd, NULL, 0, ...);

and:

	statx(dfd, "", AT_EMPTY_PATH, ...);

Change the code to reject the first option, though this means copying
the path and engaging pathwalk for the fstat() equivalent.  dfd can be a
non-directory provided path is "".

[ The timing of this isn't wonderful, but applying this now before we
  have statx() in any released kernel, before anybody starts using the
  NULL special case.    - Linus ]

Fixes: a528d35e ("statx: Add a system call to make enhanced file info available")
Reported-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: Eric Sandeen <sandeen@sandeen.net>
cc: fstests@vger.kernel.org
cc: linux-api@vger.kernel.org
cc: linux-man@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull networking fixes from David Miller:

 1) MLX5 bug fixes from Saeed Mahameed et al:
     - released wrong resources when firmware timeout happens
     - fix wrong check for encapsulation size limits
     - UAR memory leak
     - ETHTOOL_GRXCLSRLALL failed to fill in info->data

 2) Don't cache l3mdev on mis-matches local route, causes net devices to
    leak refs. From Robert Shearman.

 3) Handle fragmented SKBs properly in macsec driver, the problem is
    that we were mis-sizing the sgvec table. From Jason A. Donenfeld.

 4) We cannot have checksum offload enabled for inner UDP tunneled
    packet during IPSEC, from Ansis Atteka.

 5) Fix double SKB free in ravb driver, from Dan Carpenter.

 6) Fix CPU port handling in b53 DSA driver, from Florian Dainelli.

 7) Don't use on-stack buffers for usb_control_msg() in CAN usb driver,
    from Maksim Salau.

 8) Fix device leak in macvlan driver, from Herbert Xu. We have to purge
    the broadcast queue properly on port destroy.

 9) Fix tx ring entry limit on EF10 devices in sfc driver. From Bert
    Kenward.

10) Fix memory leaks in team driver, from Pan Bian.

11) Don't setup ipv6_stub before it can be actually used, from Paolo
    Abeni.

12) Fix tipc socket flow control accounting, from Parthasarathy
    Bhuvaragan.

13) Fix crash on module unload in hso driver, from Andreas Kemnade.

14) Fix purging of bridge multicast entries, the problem is that if we
    don't defer it to ndo_uninit it's possible for new entries to get
    added after we purge. Fix from Xin Long.

15) Don't return garbage for PACKET_HDRLEN getsockopt, from Alexander
    Potapenko.

16) Fix autoneg stall properly in PHY layer, and revert micrel driver
    change that was papering over it. From Alexander Kochetkov.

17) Don't dereference an ipv4 route as an ipv6 one in the ip6_tunnnel
    code, from Cong Wang.

18) Clear out the congestion control private of the TCP socket in all of
    the right places, from Wei Wang.

19) rawv6_ioctl measures SKB length incorrectly, fix from Jamie
    Bainbridge.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (41 commits)
  ipv6: check raw payload size correctly in ioctl
  tcp: memset ca_priv data to 0 properly
  ipv6: check skb->protocol before lookup for nexthop
  net: core: Prevent from dereferencing null pointer when releasing SKB
  macsec: dynamically allocate space for sglist
  Revert "phy: micrel: Disable auto negotiation on startup"
  net: phy: fix auto-negotiation stall due to unavailable interrupt
  net/packet: check length in getsockopt() called with PACKET_HDRLEN
  net: ipv6: regenerate host route if moved to gc list
  bridge: move bridge multicast cleanup to ndo_uninit
  ipv6: fix source routing
  qed: Fix error in the dcbx app meta data initialization.
  netvsc: fix calculation of available send sections
  net: hso: fix module unloading
  tipc: fix socket flow control accounting error at tipc_recv_stream
  tipc: fix socket flow control accounting error at tipc_send_stream
  ipv6: move stub initialization after ipv6 setup completion
  team: fix memory leaks
  sfc: tx ring can only have 2048 entries for all EF10 NICs
  macvlan: Fix device ref leak when purging bc_queue
  ...

In situations where an skb is paged, the transport header pointer and
tail pointer can be the same because the skb contents are in frags.

This results in ioctl(SIOCINQ/FIONREAD) incorrectly returning a
length of 0 when the length to receive is actually greater than zero.

skb->len is already correctly set in ip6_input_finish() with
pskb_pull(), so use skb->len as it always returns the correct result
for both linear and paged data.
Signed-off-by: NJamie Bainbridge <jbainbri@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Always zero out ca_priv data in tcp_assign_congestion_control() so that
ca_priv data is cleared out during socket creation.
Also always zero out ca_priv data in tcp_reinit_congestion_control() so
that when cc algorithm is changed, ca_priv data is cleared out as well.
We should still zero out ca_priv data even in TCP_CLOSE state because
user could call connect() on AF_UNSPEC to disconnect the socket and
leave it in TCP_CLOSE state and later call setsockopt() to switch cc
algorithm on this socket.

Fixes: 2b0a8c9e ("tcp: add CDG congestion control")
Reported-by: NAndrey Konovalov  <andreyknvl@google.com>
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Andrey reported a out-of-bound access in ip6_tnl_xmit(), this
is because we use an ipv4 dst in ip6_tnl_xmit() and cast an IPv4
neigh key as an IPv6 address:

        neigh = dst_neigh_lookup(skb_dst(skb),
                                 &ipv6_hdr(skb)->daddr);
        if (!neigh)
                goto tx_err_link_failure;

        addr6 = (struct in6_addr *)&neigh->primary_key; // <=== HERE
        addr_type = ipv6_addr_type(addr6);

        if (addr_type == IPV6_ADDR_ANY)
                addr6 = &ipv6_hdr(skb)->daddr;

        memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));

Also the network header of the skb at this point should be still IPv4
for 4in6 tunnels, we shold not just use it as IPv6 header.

This patch fixes it by checking if skb->protocol is ETH_P_IPV6: if it
is, we are safe to do the nexthop lookup using skb_dst() and
ipv6_hdr(skb)->daddr; if not (aka IPv4), we have no clue about which
dest address we can pick here, we have to rely on callers to fill it
from tunnel config, so just fall to ip6_route_output() to make the
decision.

Fixes: ea3dc960 ("ip6_tunnel: Add support for wildcard tunnel endpoints.")
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Tested-by: NAndrey Konovalov <andreyknvl@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As of tx napi, device down (`ip link set dev $dev down`) hangs unless
tx napi is enabled. Else napi_enable is not called, so napi_disable
will spin on test_and_set_bit NAPI_STATE_SCHED.

Only call napi_disable if tx napi is enabled.

Fixes: 5a719c2552ca ("virtio-net: transmit napi")
Reported-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Nathan Fontenot says:

====================
ibmvnic: Move sub crq init out of interrupt context

The sub crqs are currently intialized in interrupt context when
handling a crq response fromn the vios server. There is no reason
they must be initialized there.

Moving the initialization of the sub crqs to the ibmvnic_init routine
allows us to do the initialization outside of interrupt context and
make all of the allocations with GFP_KERNEL instead of GFP_ATOMIC.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sub crq structures are initialized in interrupt context while
handling the response to crqs when negotiating capabilities for
the driver. The sub crqs do not need to be initialized at this point
and can be moved to being done from ibmvnic_init. Moving the init
of the sub crqs to ibmvnic_init also allows use to allocate the
memory with GFP_KERNEL instead of GFP_ATOMIC.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split the sending of capability request crqs and the initialization
of sub crqs into their own routines. This is a first step to moving
the allocation of sub-crqs out of interrupt context.
Signed-off-by: NNathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Added NULL check to make __dev_kfree_skb_irq consistent with kfree
family of functions.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289Signed-off-by: NMyungho Jung <mhjungk@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The described GPIO reset property is applicable to *all* child PHYs. If
we have one reset line per PHY present on the MDIO bus, these
automatically become properties of the child PHY nodes.

Finally, indicate how the RESET pulse width must be defined, which is
the maximum value of all individual PHYs RESET pulse widths determined
by reading their datasheets.

Fixes: 69226896 ("mdio_bus: Issue GPIO RESET to PHYs.")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
tcp: do not use tcp_time_stamp for rcv autotuning

Some devices or linux distributions use HZ=100 or HZ=250

TCP receive buffer autotuning has poor behavior caused by this choice.
Since autotuning happens after 4 ms or 10 ms, short distance flows
get their receive buffer tuned to a very high value, but after an initial
period where it was frozen to (too small) initial value.

With BBR (or other CC allowing to increase BDP), we are willing to
increase tcp_rmem[2], but this receive autotuning defect is a blocker
for hosts dealing with gazillions of TCP flows in the data centers,
since many of them have inflated RCVBUF. Risk of OOM is too high.

Note that TSO autodefer, tcp cubic, and TCP TS options (RFC 7323)
also suffer from our dependency to jiffies (via tcp_time_stamp).

We have ongoing efforts to improve all that in the future.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some devices or distributions use HZ=100 or HZ=250

TCP receive buffer autotuning has poor behavior caused by this choice.
Since autotuning happens after 4 ms or 10 ms, short distance flows
get their receive buffer tuned to a very high value, but after an initial
period where it was frozen to (too small) initial value.

With tp->tcp_mstamp introduction, we can switch to high resolution
timestamps almost for free (at the expense of 8 additional bytes per
TCP structure)

Note that some TCP stacks use usec TCP timestamps where this
patch makes even more sense : Many TCP flows have < 500 usec RTT.
Hopefully this finer TS option can be standardized soon.

Tested:
 HZ=100 kernel
 ./netperf -H lpaa24 -t TCP_RR -l 1000 -- -r 10000,10000 &

 Peer without patch :
 lpaa24:~# ss -tmi dst lpaa23
 ...
 skmem:(r0,rb8388608,...)
 rcv_rtt:10 rcv_space:3210000 minrtt:0.017

 Peer with the patch :
 lpaa23:~# ss -tmi dst lpaa24
 ...
 skmem:(r0,rb428800,...)
 rcv_rtt:0.069 rcv_space:30000 minrtt:0.017

We can see saner RCVBUF, and more precise rcv_rtt information.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is no longer needed, everything uses tp->tcp_mstamp instead.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following patch will remove ack_time from struct tcp_sacktag_state

Same info is now found in tp->tcp_mstamp
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No longer needed, since tp->tcp_mstamp holds the information.

This is needed to remove sack_state.ack_time in a following patch.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No longer needed, since tp->tcp_mstamp holds the information.

This is needed to remove sack_state.ack_time in a following patch.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not used anymore now tp->tcp_mstamp holds the information.

This is needed to remove sack_state.ack_time in a following patch.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not used anymore now tp->tcp_mstamp holds the information.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is no longer used, since tcp_rack_detect_loss() takes
the timestamp from tp->tcp_mstamp
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can use tp->tcp_mstamp as it contains a recent timestamp.

This removes a call to skb_mstamp_get() from tcp_rack_reo_timeout()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We want to use precise timestamps in TCP stack, but we do not
want to call possibly expensive kernel time services too often.

tp->tcp_mstamp is guaranteed to be updated once per incoming packet.

We will use it in the following patches, removing specific
skb_mstamp_get() calls, and removing ack_time from
struct tcp_sacktag_state.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We call skb_cow_data, which is good anyway to ensure we can actually
modify the skb as such (another error from prior). Now that we have the
number of fragments required, we can safely allocate exactly that amount
of memory.

Fixes: c09440f7 ("macsec: introduce IEEE 802.1AE driver")
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Acked-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

no users in the tree, insecure_max_entries is always set to
ht->p.max_size * 2 in rhtashtable_init().

Replace only spot that uses it with a ht->p.max_size check.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 99f81afc.

It was papering over the real problem, which is fixed by commit
f555f34f ("net: phy: fix auto-negotiation stall due to unavailable
interrupt")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Ethernet link on an interrupt driven PHY was not coming up if the Ethernet
cable was plugged before the Ethernet interface was brought up.

The patch trigger PHY state machine to update link state if PHY was requested to
do auto-negotiation and auto-negotiation complete flag already set.

During power-up cycle the PHY do auto-negotiation, generate interrupt and set
auto-negotiation complete flag. Interrupt is handled by PHY state machine but
doesn't update link state because PHY is in PHY_READY state. After some time
MAC bring up, start and request PHY to do auto-negotiation. If there are no new
settings to advertise genphy_config_aneg() doesn't start PHY auto-negotiation.
PHY continue to stay in auto-negotiation complete state and doesn't fire
interrupt. At the same time PHY state machine expect that PHY started
auto-negotiation and is waiting for interrupt from PHY and it won't get it.

Fixes: 321beec5 ("net: phy: Use interrupts when available in NOLINK state")
Signed-off-by: NAlexander Kochetkov <al.kochet@gmail.com>
Cc: stable <stable@vger.kernel.org> # v4.9+
Tested-by: NRoger Quadros <rogerq@ti.com>
Tested-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull sound fixes from Takashi Iwai:
 "Since we got a bonus week, let me try to screw a few pending fixes.

  A slightly large fix is the locking fix in ASoC STI driver, but it's
  pretty board-specific, and the risk is fairly low.

  All the rest are small / trivial fixes, mostly marked as stable, for
  ALSA sequencer core, ASoC topology, ASoC Intel bytcr and Firewire
  drivers"

* tag 'sound-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ASoC: intel: Fix PM and non-atomic crash in bytcr drivers
  ALSA: firewire-lib: fix inappropriate assignment between signed/unsigned type
  ALSA: seq: Don't break snd_use_lock_sync() loop by timeout
  ASoC: topology: Fix to store enum text values
  ASoC: STI: Fix null ptr deference in IRQ handler
  ALSA: oxfw: fix regression to handle Stanton SCS.1m/1d

Pull ARC fix from Vineet Gupta:
 "Last minute fixes for ARC:

   - build error in Mellanox nps platform

   - addressing lack of saving FPU regs in releavnt configs"

* tag 'arc-4.11-final' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARCv2: entry: save Accumulator register pair (r58:59) if present
  ARC: [plat-eznps] Fix build error

(struct net_device, xdp_prog) field should be moved in RX cache lines,
reducing latencies when a single packet is received on idle host,
since netif_elide_gro() needs it.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the case getsockopt() is called with PACKET_HDRLEN and optlen < 4
|val| remains uninitialized and the syscall may behave differently
depending on its value, and even copy garbage to userspace on certain
architectures. To fix this we now return -EINVAL if optlen is too small.

This bug has been detected with KMSAN.
Signed-off-by: NAlexander Potapenko <glider@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Taking down the loopback device wreaks havoc on IPv6 routing. By
extension, taking down a VRF device wreaks havoc on its table.

Dmitry and Andrey both reported heap out-of-bounds reports in the IPv6
FIB code while running syzkaller fuzzer. The root cause is a dead dst
that is on the garbage list gets reinserted into the IPv6 FIB. While on
the gc (or perhaps when it gets added to the gc list) the dst->next is
set to an IPv4 dst. A subsequent walk of the ipv6 tables causes the
out-of-bounds access.

Andrey's reproducer was the key to getting to the bottom of this.

With IPv6, host routes for an address have the dst->dev set to the
loopback device. When the 'lo' device is taken down, rt6_ifdown initiates
a walk of the fib evicting routes with the 'lo' device which means all
host routes are removed. That process moves the dst which is attached to
an inet6_ifaddr to the gc list and marks it as dead.

The recent change to keep global IPv6 addresses added a new function,
fixup_permanent_addr, that is called on admin up. That function restarts
dad for an inet6_ifaddr and when it completes the host route attached
to it is inserted into the fib. Since the route was marked dead and
moved to the gc list, re-inserting the route causes the reported
out-of-bounds accesses. If the device with the address is taken down
or the address is removed, the WARN_ON in fib6_del is triggered.

All of those faults are fixed by regenerating the host route if the
existing one has been moved to the gc list, something that can be
determined by checking if the rt6i_ref counter is 0.

Fixes: f1705ec1 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During removing a bridge device, if the bridge is still up, a new mdb entry
still can be added in br_multicast_add_group() after all mdb entries are
removed in br_multicast_dev_del(). Like the path:

  mld_ifc_timer_expire ->
    mld_sendpack -> ...
      br_multicast_rcv ->
        br_multicast_add_group

The new mp's timer will be set up. If the timer expires after the bridge
is freed, it may cause use-after-free panic in br_multicast_group_expired.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
IP: [<ffffffffa07ed2c8>] br_multicast_group_expired+0x28/0xb0 [bridge]
Call Trace:
 <IRQ>
 [<ffffffff81094536>] call_timer_fn+0x36/0x110
 [<ffffffffa07ed2a0>] ? br_mdb_free+0x30/0x30 [bridge]
 [<ffffffff81096967>] run_timer_softirq+0x237/0x340
 [<ffffffff8108dcbf>] __do_softirq+0xef/0x280
 [<ffffffff8169889c>] call_softirq+0x1c/0x30
 [<ffffffff8102c275>] do_softirq+0x65/0xa0
 [<ffffffff8108e055>] irq_exit+0x115/0x120
 [<ffffffff81699515>] smp_apic_timer_interrupt+0x45/0x60
 [<ffffffff81697a5d>] apic_timer_interrupt+0x6d/0x80

Nikolay also found it would cause a memory leak - the mdb hash is
reallocated and not freed due to the mdb rehash.

unreferenced object 0xffff8800540ba800 (size 2048):
  backtrace:
    [<ffffffff816e2287>] kmemleak_alloc+0x67/0xc0
    [<ffffffff81260bea>] __kmalloc+0x1ba/0x3e0
    [<ffffffffa05c60ee>] br_mdb_rehash+0x5e/0x340 [bridge]
    [<ffffffffa05c74af>] br_multicast_new_group+0x43f/0x6e0 [bridge]
    [<ffffffffa05c7aa3>] br_multicast_add_group+0x203/0x260 [bridge]
    [<ffffffffa05ca4b5>] br_multicast_rcv+0x945/0x11d0 [bridge]
    [<ffffffffa05b6b10>] br_dev_xmit+0x180/0x470 [bridge]
    [<ffffffff815c781b>] dev_hard_start_xmit+0xbb/0x3d0
    [<ffffffff815c8743>] __dev_queue_xmit+0xb13/0xc10
    [<ffffffff815c8850>] dev_queue_xmit+0x10/0x20
    [<ffffffffa02f8d7a>] ip6_finish_output2+0x5ca/0xac0 [ipv6]
    [<ffffffffa02fbfc6>] ip6_finish_output+0x126/0x2c0 [ipv6]
    [<ffffffffa02fc245>] ip6_output+0xe5/0x390 [ipv6]
    [<ffffffffa032b92c>] NF_HOOK.constprop.44+0x6c/0x240 [ipv6]
    [<ffffffffa032bd16>] mld_sendpack+0x216/0x3e0 [ipv6]
    [<ffffffffa032d5eb>] mld_ifc_timer_expire+0x18b/0x2b0 [ipv6]

This could happen when ip link remove a bridge or destroy a netns with a
bridge device inside.

With Nikolay's suggestion, this patch is to clean up bridge multicast in
ndo_uninit after bridge dev is shutdown, instead of br_dev_delete, so
that netif_running check in br_multicast_add_group can avoid this issue.

v1->v2:
  - fix this issue by moving br_multicast_dev_del to ndo_uninit, instead
    of calling dev_close in br_dev_delete.

(NOTE: Depends upon b6fe0440 ("bridge: implement missing ndo_uninit()"))

Fixes: e10177ab ("bridge: multicast: fix handling of temp and perm entries")
Reported-by: NJianwen Ji <jiji@redhat.com>
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Reviewed-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>