We should always do a read of current value of XGMAC_VLAN_TAG instead of
directly overwriting the register value.

Fixes: 3cd1cfcb ("net: stmmac: Implement VLAN Hash Filtering in XGMAC")
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It should always do a read of current value of GMAC_VLAN_TAG instead of
directly overwriting the register value.

Fixes: c1be0022 ("net: stmmac: Add VLAN HASH filtering support in GMAC4+")
Signed-off-by: Tan, Tee Min <tee.min.tan@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The caller of XDP_SETUP_PROG has already incremented refcnt in
__bpf_prog_get(), so drivers should only increment refcnt by
num_queues - 1.

To fix the issue, update netvsc_xdp_set() to add the correct number
to refcnt.

Hold a refcnt in netvsc_xdp_set()’s other caller, netvsc_attach().

And, do the same in netvsc_vf_setxdp(). Otherwise, every time when VF is
removed and added from the host side, the refcnt will be decreased by one,
which may cause page fault when unloading xdp program.

Fixes: 351e1581 ("hv_netvsc: Add XDP support")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vinicius Costa Gomes says:

====================
taprio: Some fixes

Changes from v3:
  - Replaced ENOTSUPP error code with EOPNOTSUPP (Jakub Kicinski);
  - Added the missing policy validation for the flags netlink argument
    (Jakub Kicinski);
  - Fixed the destroy() flow to also destroy the priority to traffic
    class mapping (David Miller);
  - Fixed dropping packets when taprio offloading is used together
    with ETF offloading (more on this below);

Changes from v2:
  - Squashed commits 2/3 and 3/3 into a single one (I think a single
    commit is going to be easier to review);
  - Removed an "improvement" that was causing changes in user visible
    behavior;

Changes from v1:
  - Fixed ignoring the 'flags' argument when adding a new
    instance (Vladimir Oltean);
  - Changed the order of commits;

Updated cover letter:

One bit that might need some attention is the fix for not dropping all
packets when taprio and ETF offloading are used, patch 5/5. The
behavior when the fix is applied is that packets that have a 'txtime'
that would fall outside of their transmission window are now dropped
by taprio. The question that might be raised is: should taprio be
responsible for dropping these packets, or should it be handled lower
in the stack?

My opinion is: taprio has all the information, and it's able to give
feeback to the user. Lower in the stack, those packets might go into
the void, and the only feedback could be a hard to find counter
increasing.

Patch 1/5: Reported by Po Liu, is more of a improvement of usability for
drivers implementing offloading features, now they can rely on the
value of dev->num_tc, instead of going through some hops to get this
value.

Patch 2/5: Use 'q->flags' as the source of truth for the offloading
flags. Tries to solidify the current behavior, while avoiding going
into invalid states, one of which was causing a "rcu stall" (more
information in the commit message).

Patch 3/5: Adds the missing netlink attribute validation for
TCA_TAPRIO_ATTR_FLAGS.

Patch 4/5: Replaces the usage of netdev_set_num_tc() with
netdev_reset_tc() in taprio_destroy(), taprio_destroy() is called when
applying a configuration fails, making sure that the device traffic
class configuration goes back to the default state.

@Vladimir: If possible, I would appreciate your Ack on patch 2/5. I
have been looking at this code for so long that I might have missed
something obvious (and my growing dislike for the word 'flags' may be
affecting my judgement :-).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When using taprio offloading together with ETF offloading, configured
like this, for example:

$ tc qdisc replace dev $IFACE parent root handle 100 taprio \
  	num_tc 4 \
        map 2 2 1 0 3 2 2 2 2 2 2 2 2 2 2 2 \
	queues 1@0 1@1 1@2 1@3 \
	base-time $BASE_TIME \
	sched-entry S 01 1000000 \
	sched-entry S 0e 1000000 \
	flags 0x2

$ tc qdisc replace dev $IFACE parent 100:1 etf \
     	offload delta 300000 clockid CLOCK_TAI

During enqueue, it works out that the verification added for the
"txtime" assisted mode is run when using taprio + ETF offloading, the
only thing missing is initializing the 'next_txtime' of all the cycle
entries. (if we don't set 'next_txtime' all packets from SO_TXTIME
sockets are dropped)

Fixes: 4cfd5779 ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When destroying the current taprio instance, which can happen when the
creation of one fails, we should reset the traffic class configuration
back to the default state.

netdev_reset_tc() is a better way because in addition to setting the
number of traffic classes to zero, it also resets the priority to
traffic classes mapping to the default value.

Fixes: 5a781ccb ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netlink policy validation for the 'flags' argument was missing.

Fixes: 4cfd5779 ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Because 'q->flags' starts as zero, and zero is a valid value, we
aren't able to detect the transition from zero to something else
during "runtime".

The solution is to initialize 'q->flags' with an invalid value, so we
can detect if 'q->flags' was set by the user or not.

To better solidify the behavior, 'flags' handling is moved to a
separate function. The behavior is:
 - 'flags' if unspecified by the user, is assumed to be zero;
 - 'flags' cannot change during "runtime" (i.e. a change() request
 cannot modify it);

With this new function we can remove taprio_flags, which should reduce
the risk of future accidents.

Allowing flags to be changed was causing the following RCU stall:

[ 1730.558249] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 1730.558258] rcu: 	  6-...0: (190 ticks this GP) idle=922/0/0x1 softirq=25580/25582 fqs=16250
[ 1730.558264] 		  (detected by 2, t=65002 jiffies, g=33017, q=81)
[ 1730.558269] Sending NMI from CPU 2 to CPUs 6:
[ 1730.559277] NMI backtrace for cpu 6
[ 1730.559277] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G            E     5.5.0-rc6+ #35
[ 1730.559278] Hardware name: Gigabyte Technology Co., Ltd. Z390 AORUS ULTRA/Z390 AORUS ULTRA-CF, BIOS F7 03/14/2019
[ 1730.559278] RIP: 0010:__hrtimer_run_queues+0xe2/0x440
[ 1730.559278] Code: 48 8b 43 28 4c 89 ff 48 8b 75 c0 48 89 45 c8 e8 f4 bb 7c 00 0f 1f 44 00 00 65 8b 05 40 31 f0 68 89 c0 48 0f a3 05 3e 5c 25 01 <0f> 82 fc 01 00 00 48 8b 45 c8 48 89 df ff d0 89 45 c8 0f 1f 44 00
[ 1730.559279] RSP: 0018:ffff9970802d8f10 EFLAGS: 00000083
[ 1730.559279] RAX: 0000000000000006 RBX: ffff8b31645bff38 RCX: 0000000000000000
[ 1730.559280] RDX: 0000000000000000 RSI: ffffffff9710f2ec RDI: ffffffff978daf0e
[ 1730.559280] RBP: ffff9970802d8f68 R08: 0000000000000000 R09: 0000000000000000
[ 1730.559280] R10: 0000018336d7944e R11: 0000000000000001 R12: ffff8b316e39f9c0
[ 1730.559281] R13: ffff8b316e39f940 R14: ffff8b316e39f998 R15: ffff8b316e39f7c0
[ 1730.559281] FS:  0000000000000000(0000) GS:ffff8b316e380000(0000) knlGS:0000000000000000
[ 1730.559281] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1730.559281] CR2: 00007f1105303760 CR3: 0000000227210005 CR4: 00000000003606e0
[ 1730.559282] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1730.559282] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1730.559282] Call Trace:
[ 1730.559282]  <IRQ>
[ 1730.559283]  ? taprio_dequeue_soft+0x2d0/0x2d0 [sch_taprio]
[ 1730.559283]  hrtimer_interrupt+0x104/0x220
[ 1730.559283]  ? irqtime_account_irq+0x34/0xa0
[ 1730.559283]  smp_apic_timer_interrupt+0x6d/0x230
[ 1730.559284]  apic_timer_interrupt+0xf/0x20
[ 1730.559284]  </IRQ>
[ 1730.559284] RIP: 0010:cpu_idle_poll+0x35/0x1a0
[ 1730.559285] Code: 88 82 ff 65 44 8b 25 12 7d 73 68 0f 1f 44 00 00 e8 90 c3 89 ff fb 65 48 8b 1c 25 c0 7e 01 00 48 8b 03 a8 08 74 0b eb 1c f3 90 <48> 8b 03 a8 08 75 13 8b 05 be a8 a8 00 85 c0 75 ed e8 75 48 84 ff
[ 1730.559285] RSP: 0018:ffff997080137ea8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
[ 1730.559285] RAX: 0000000000000001 RBX: ffff8b316bc3c580 RCX: 0000000000000000
[ 1730.559286] RDX: 0000000000000001 RSI: 000000002819aad9 RDI: ffffffff978da730
[ 1730.559286] RBP: ffff997080137ec0 R08: 0000018324a6d387 R09: 0000000000000000
[ 1730.559286] R10: 0000000000000400 R11: 0000000000000001 R12: 0000000000000006
[ 1730.559286] R13: ffff8b316bc3c580 R14: 0000000000000000 R15: 0000000000000000
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  do_idle+0x4d/0x1f0
[ 1730.559287]  ? complete+0x44/0x50
[ 1730.559288]  cpu_startup_entry+0x1b/0x20
[ 1730.559288]  start_secondary+0x142/0x180
[ 1730.559288]  secondary_startup_64+0xb6/0xc0
[ 1776.686313] nvme nvme0: I/O 96 QID 1 timeout, completion polled

Fixes: 4cfd5779 ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If the driver implementing taprio offloading depends on the value of
the network device number of traffic classes (dev->num_tc) for
whatever reason, it was going to receive the value zero. The value was
only set after the offloading function is called.

So, moving setting the number of traffic classes to before the
offloading function is called fixes this issue. This is safe because
this only happens when taprio is instantiated (we don't allow this
configuration to be changed without first removing taprio).

Fixes: 9c66d156 ("taprio: Add support for hardware offloading")
Reported-by: Po Liu <po.liu@nxp.com>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The 7445 switch clocking profiles do not allow us to run the IMP port at
2Gb/sec in a way that it is reliable and consistent. Make sure that the
setting is only applied to the 7278 family.

Fixes: 8f1880cb ("net: dsa: bcm_sf2: Configure IMP port for 2Gb/sec")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

b53_configure_vlan() is called by the bcm_sf2 driver upon setup and
indirectly through resume as well. During the initial setup, we are
guaranteed that dev->vlan_enabled is false, so there is no change in
behavior, however during suspend, we may have enabled VLANs before, so we
do want to restore that setting.

Fixes: dad8d7c6 ("net: dsa: b53: Properly account for VLAN filtering")
Fixes: 967dd82f ("net: dsa: b53: Add support for Broadcom RoboSwitch")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It forgot to reduce the value of the variable retry in a while loop
in the ethqos_configure() function. It may cause an endless loop and
without timeout.

Fixes: a7c30e62 ("net: stmmac: Add driver for Qualcomm ethqos")
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rxrpc_rcu_destroy_call(), which is called as an RCU callback to clean up a
put call, calls rxrpc_put_connection() which, deep in its bowels, takes a
number of spinlocks in a non-BH-safe way, including rxrpc_conn_id_lock and
local->client_conns_lock.  RCU callbacks, however, are normally called from
softirq context, which can cause lockdep to notice the locking
inconsistency.

To get lockdep to detect this, it's necessary to have the connection
cleaned up on the put at the end of the last of its calls, though normally
the clean up is deferred.  This can be induced, however, by starting a call
on an AF_RXRPC socket and then closing the socket without reading the
reply.

Fix this by having rxrpc_rcu_destroy_call() punt the destruction to a
workqueue if in softirq-mode and defer the destruction to process context.

Note that another way to fix this could be to add a bunch of bh-disable
annotations to the spinlocks concerned - and there might be more than just
those two - but that means spending more time with BHs disabled.

Note also that some of these places were covered by bh-disable spinlocks
belonging to the rxrpc_transport object, but these got removed without the
_bh annotation being retained on the next lock in.

Fixes: 999b69f8 ("rxrpc: Kill the client connection bundle concept")
Reported-by: syzbot+d82f3ac8d87e7ccbb2c9@syzkaller.appspotmail.com
Reported-by: syzbot+3f1fd6b8cbf8702d134e@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hillf Danton <hdanton@sina.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The recent patch that substituted a flag on an rxrpc_call for the
connection pointer being NULL as an indication that a call was disconnected
puts the set_bit in the wrong place for service calls.  This is only a
problem if a call is implicitly terminated by a new call coming in on the
same connection channel instead of a terminating ACK packet.

In such a case, rxrpc_input_implicit_end_call() calls
__rxrpc_disconnect_call(), which is now (incorrectly) setting the
disconnection bit, meaning that when rxrpc_release_call() is later called,
it doesn't call rxrpc_disconnect_call() and so the call isn't removed from
the peer's error distribution list and the list gets corrupted.

KASAN finds the issue as an access after release on a call, but the
position at which it occurs is confusing as it appears to be related to a
different call (the call site is where the latter call is being removed
from the error distribution list and either the next or pprev pointer
points to a previously released call).

Fix this by moving the setting of the flag from __rxrpc_disconnect_call()
to rxrpc_disconnect_call() in the same place that the connection pointer
was being cleared.

Fixes: 5273a191 ("rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
Mellanox, mlx5 fixes 2020-02-06

This series introduces some fixes to mlx5 driver.

Please pull and let me know if there is any problem.

For -stable v4.19:
 ('net/mlx5: IPsec, Fix esp modify function attribute')
 ('net/mlx5: IPsec, fix memory leak at mlx5_fpga_ipsec_delete_sa_ctx')

For -stable v5.4:
   ('net/mlx5: Deprecate usage of generic TLS HW capability bit')
   ('net/mlx5: Fix deadlock in fs_core')

For -stable v5.5:
   ('net/mlx5e: TX, Error completion is for last WQE in batch')
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Deprecate the generic TLS cap bit, use the new TX-specific
TLS cap bit instead.

Fixes: a12ff35e ("net/mlx5: Introduce TLS TX offload hardware bits and structures")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

For a cyclic work queue, when not requesting a completion per WQE,
a single CQE might indicate the completion of several WQEs.
However, in case some WQE in the batch causes an error, then an error
completion is issued, breaking the batch, and pointing to the offending
WQE in the wqe_counter field.

Hence, WQE-specific error CQE handling (like printing, breaking, etc...)
should be performed only for the last WQE in batch.

Fixes: 130c7b46 ("net/mlx5e: TX, Dump WQs wqe descriptors on CQE with error events")
Fixes: fd9b4be8 ("net/mlx5e: RX, Support multiple outstanding UMR posts")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Aya Levin <ayal@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

SA context is allocated at mlx5_fpga_ipsec_create_sa_ctx,
however the counterpart mlx5_fpga_ipsec_delete_sa_ctx function
nullifies sa_ctx pointer without freeing the memory allocated,
hence the memory leak.

Fix by free SA context when the SA is released.

Fixes: d6c4f029 ("net/mlx5: Refactor accel IPSec code")
Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

The function mlx5_fpga_esp_validate_xfrm_attrs is wrongly used
with negative negation as zero value indicates success but it
used as failure return value instead.

Fix by remove the unary not negation operator.

Fixes: 05564d0a ("net/mlx5: Add flow-steering commands for FPGA IPSec implementation")
Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

free_match_list could be called when the flow table is already
locked. We need to pass this notation to tree_put_node.

It fixes the following lockdep warnning:

[ 1797.268537] ============================================
[ 1797.276837] WARNING: possible recursive locking detected
[ 1797.285101] 5.5.0-rc5+ #10 Not tainted
[ 1797.291641] --------------------------------------------
[ 1797.299917] handler10/9296 is trying to acquire lock:
[ 1797.307885] ffff889ad399a0a0 (&node->lock){++++}, at:
tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.319694]
[ 1797.319694] but task is already holding lock:
[ 1797.330904] ffff889ad399a0a0 (&node->lock){++++}, at:
nested_down_write_ref_node.part.33+0x1a/0x60 [mlx5_core]
[ 1797.344707]
[ 1797.344707] other info that might help us debug this:
[ 1797.356952]  Possible unsafe locking scenario:
[ 1797.356952]
[ 1797.368333]        CPU0
[ 1797.373357]        ----
[ 1797.378364]   lock(&node->lock);
[ 1797.384222]   lock(&node->lock);
[ 1797.390031]
[ 1797.390031]  *** DEADLOCK ***
[ 1797.390031]
[ 1797.403003]  May be due to missing lock nesting notation
[ 1797.403003]
[ 1797.414691] 3 locks held by handler10/9296:
[ 1797.421465]  #0: ffff889cf2c5a110 (&block->cb_lock){++++}, at:
tc_setup_cb_add+0x70/0x250
[ 1797.432810]  #1: ffff88a030081490 (&comp->sem){++++}, at:
mlx5_devcom_get_peer_data+0x4c/0xb0 [mlx5_core]
[ 1797.445829]  #2: ffff889ad399a0a0 (&node->lock){++++}, at:
nested_down_write_ref_node.part.33+0x1a/0x60 [mlx5_core]
[ 1797.459913]
[ 1797.459913] stack backtrace:
[ 1797.469436] CPU: 1 PID: 9296 Comm: handler10 Kdump: loaded Not
tainted 5.5.0-rc5+ #10
[ 1797.480643] Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS
2.4.3 01/17/2017
[ 1797.491480] Call Trace:
[ 1797.496701]  dump_stack+0x96/0xe0
[ 1797.502864]  __lock_acquire.cold.63+0xf8/0x212
[ 1797.510301]  ? lockdep_hardirqs_on+0x250/0x250
[ 1797.517701]  ? mark_held_locks+0x55/0xa0
[ 1797.524547]  ? quarantine_put+0xb7/0x160
[ 1797.531422]  ? lockdep_hardirqs_on+0x17d/0x250
[ 1797.538913]  lock_acquire+0xd6/0x1f0
[ 1797.545529]  ? tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.553701]  down_write+0x94/0x140
[ 1797.560206]  ? tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.568464]  ? down_write_killable_nested+0x170/0x170
[ 1797.576925]  ? del_hw_flow_group+0xde/0x1f0 [mlx5_core]
[ 1797.585629]  tree_put_node+0x1d5/0x210 [mlx5_core]
[ 1797.593891]  ? free_match_list.part.25+0x147/0x170 [mlx5_core]
[ 1797.603389]  free_match_list.part.25+0xe0/0x170 [mlx5_core]
[ 1797.612654]  _mlx5_add_flow_rules+0x17e2/0x20b0 [mlx5_core]
[ 1797.621838]  ? lock_acquire+0xd6/0x1f0
[ 1797.629028]  ? esw_get_prio_table+0xb0/0x3e0 [mlx5_core]
[ 1797.637981]  ? alloc_insert_flow_group+0x420/0x420 [mlx5_core]
[ 1797.647459]  ? try_to_wake_up+0x4c7/0xc70
[ 1797.654881]  ? lock_downgrade+0x350/0x350
[ 1797.662271]  ? __mutex_unlock_slowpath+0xb1/0x3f0
[ 1797.670396]  ? find_held_lock+0xac/0xd0
[ 1797.677540]  ? mlx5_add_flow_rules+0xdc/0x360 [mlx5_core]
[ 1797.686467]  mlx5_add_flow_rules+0xdc/0x360 [mlx5_core]
[ 1797.695134]  ? _mlx5_add_flow_rules+0x20b0/0x20b0 [mlx5_core]
[ 1797.704270]  ? irq_exit+0xa5/0x170
[ 1797.710764]  ? retint_kernel+0x10/0x10
[ 1797.717698]  ? mlx5_eswitch_set_rule_source_port.isra.9+0x122/0x230
[mlx5_core]
[ 1797.728708]  mlx5_eswitch_add_offloaded_rule+0x465/0x6d0 [mlx5_core]
[ 1797.738713]  ? mlx5_eswitch_get_prio_range+0x30/0x30 [mlx5_core]
[ 1797.748384]  ? mlx5_fc_stats_work+0x670/0x670 [mlx5_core]
[ 1797.757400]  mlx5e_tc_offload_fdb_rules.isra.27+0x24/0x90 [mlx5_core]
[ 1797.767665]  mlx5e_tc_add_fdb_flow+0xaf8/0xd40 [mlx5_core]
[ 1797.776886]  ? mlx5e_encap_put+0xd0/0xd0 [mlx5_core]
[ 1797.785562]  ? mlx5e_alloc_flow.isra.43+0x18c/0x1c0 [mlx5_core]
[ 1797.795353]  __mlx5e_add_fdb_flow+0x2e2/0x440 [mlx5_core]
[ 1797.804558]  ? mlx5e_tc_update_neigh_used_value+0x8c0/0x8c0
[mlx5_core]
[ 1797.815093]  ? wait_for_completion+0x260/0x260
[ 1797.823272]  mlx5e_configure_flower+0xe94/0x1620 [mlx5_core]
[ 1797.832792]  ? __mlx5e_add_fdb_flow+0x440/0x440 [mlx5_core]
[ 1797.842096]  ? down_read+0x11a/0x2e0
[ 1797.849090]  ? down_write+0x140/0x140
[ 1797.856142]  ? mlx5e_rep_indr_setup_block_cb+0xc0/0xc0 [mlx5_core]
[ 1797.866027]  tc_setup_cb_add+0x11a/0x250
[ 1797.873339]  fl_hw_replace_filter+0x25e/0x320 [cls_flower]
[ 1797.882385]  ? fl_hw_destroy_filter+0x1c0/0x1c0 [cls_flower]
[ 1797.891607]  fl_change+0x1d54/0x1fb6 [cls_flower]
[ 1797.899772]  ? __rhashtable_insert_fast.constprop.50+0x9f0/0x9f0
[cls_flower]
[ 1797.910728]  ? lock_downgrade+0x350/0x350
[ 1797.918187]  ? __radix_tree_lookup+0xa5/0x130
[ 1797.926046]  ? fl_set_key+0x1590/0x1590 [cls_flower]
[ 1797.934611]  ? __rhashtable_insert_fast.constprop.50+0x9f0/0x9f0
[cls_flower]
[ 1797.945673]  tc_new_tfilter+0xcd1/0x1240
[ 1797.953138]  ? tc_del_tfilter+0xb10/0xb10
[ 1797.960688]  ? avc_has_perm_noaudit+0x92/0x320
[ 1797.968721]  ? avc_has_perm_noaudit+0x1df/0x320
[ 1797.976816]  ? avc_has_extended_perms+0x990/0x990
[ 1797.985090]  ? mark_lock+0xaa/0x9e0
[ 1797.991988]  ? match_held_lock+0x1b/0x240
[ 1797.999457]  ? match_held_lock+0x1b/0x240
[ 1798.006859]  ? find_held_lock+0xac/0xd0
[ 1798.014045]  ? symbol_put_addr+0x40/0x40
[ 1798.021317]  ? rcu_read_lock_sched_held+0xd0/0xd0
[ 1798.029460]  ? tc_del_tfilter+0xb10/0xb10
[ 1798.036810]  rtnetlink_rcv_msg+0x4d5/0x620
[ 1798.044236]  ? rtnl_bridge_getlink+0x460/0x460
[ 1798.052034]  ? lockdep_hardirqs_on+0x250/0x250
[ 1798.059837]  ? match_held_lock+0x1b/0x240
[ 1798.067146]  ? find_held_lock+0xac/0xd0
[ 1798.074246]  netlink_rcv_skb+0xc6/0x1f0
[ 1798.081339]  ? rtnl_bridge_getlink+0x460/0x460
[ 1798.089104]  ? netlink_ack+0x440/0x440
[ 1798.096061]  netlink_unicast+0x2d4/0x3b0
[ 1798.103189]  ? netlink_attachskb+0x3f0/0x3f0
[ 1798.110724]  ? _copy_from_iter_full+0xda/0x370
[ 1798.118415]  netlink_sendmsg+0x3ba/0x6a0
[ 1798.125478]  ? netlink_unicast+0x3b0/0x3b0
[ 1798.132705]  ? netlink_unicast+0x3b0/0x3b0
[ 1798.139880]  sock_sendmsg+0x94/0xa0
[ 1798.146332]  ____sys_sendmsg+0x36c/0x3f0
[ 1798.153251]  ? copy_msghdr_from_user+0x165/0x230
[ 1798.160941]  ? kernel_sendmsg+0x30/0x30
[ 1798.167738]  ___sys_sendmsg+0xeb/0x150
[ 1798.174411]  ? sendmsg_copy_msghdr+0x30/0x30
[ 1798.181649]  ? lock_downgrade+0x350/0x350
[ 1798.188559]  ? rcu_read_lock_sched_held+0xd0/0xd0
[ 1798.196239]  ? __fget+0x21d/0x320
[ 1798.202335]  ? do_dup2+0x2a0/0x2a0
[ 1798.208499]  ? lock_downgrade+0x350/0x350
[ 1798.215366]  ? __fget_light+0xd6/0xf0
[ 1798.221808]  ? syscall_trace_enter+0x369/0x5d0
[ 1798.229112]  __sys_sendmsg+0xd3/0x160
[ 1798.235511]  ? __sys_sendmsg_sock+0x60/0x60
[ 1798.242478]  ? syscall_trace_enter+0x233/0x5d0
[ 1798.249721]  ? syscall_slow_exit_work+0x280/0x280
[ 1798.257211]  ? do_syscall_64+0x1e/0x2e0
[ 1798.263680]  do_syscall_64+0x72/0x2e0
[ 1798.269950]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: bd71b08e ("net/mlx5: Support multiple updates of steering rules in parallel")
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

After a number of suspend and resume cycles, it is possible for the RBUF
to be stuck in Wake-on-LAN mode, despite the MPD enable bit being
cleared which instructed the RBUF to exit that mode.

Avoid creating that problematic condition by clearing the RX_EN and
TX_EN bits in the UniMAC prior to disable the Magic Packet Detector
logic which is guaranteed to make the RBUF exit Wake-on-LAN mode.

Fixes: 83e82f4c ("net: systemport: add Wake-on-LAN support")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It turned out that on low performance systems the original change can
cause lower tx performance. On a N3450-based mini-PC tx performance
in iperf3 was reduced from 950Mbps to ~900Mbps. Therefore effectively
revert the original change, just use pcie_set_readrq() now instead of
changing the PCIe capability register directly.

Fixes: 2df49d36 ("r8169: remove fiddling with the PCIe max read request size")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The bug is that we call kfree_skb(skb) and then pass "skb" to
qdisc_pkt_len(skb) on the next line, which is a use after free.
Also Cong Wang points out that it's better to delay the actual
frees until we drop the rtnl lock so we should use rtnl_kfree_skbs()
instead of kfree_skb().

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Fixes: ec97ecf1 ("net: sched: add Flow Queue PIE packet scheduler")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sk_buff.qlen can be accessed concurrently as noticed by KCSAN,

 BUG: KCSAN: data-race in __skb_try_recv_from_queue / unix_dgram_sendmsg

 read to 0xffff8a1b1d8a81c0 of 4 bytes by task 5371 on cpu 96:
  unix_dgram_sendmsg+0x9a9/0xb70 include/linux/skbuff.h:1821
				 net/unix/af_unix.c:1761
  ____sys_sendmsg+0x33e/0x370
  ___sys_sendmsg+0xa6/0xf0
  __sys_sendmsg+0x69/0xf0
  __x64_sys_sendmsg+0x51/0x70
  do_syscall_64+0x91/0xb47
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 write to 0xffff8a1b1d8a81c0 of 4 bytes by task 1 on cpu 99:
  __skb_try_recv_from_queue+0x327/0x410 include/linux/skbuff.h:2029
  __skb_try_recv_datagram+0xbe/0x220
  unix_dgram_recvmsg+0xee/0x850
  ____sys_recvmsg+0x1fb/0x210
  ___sys_recvmsg+0xa2/0xf0
  __sys_recvmsg+0x66/0xf0
  __x64_sys_recvmsg+0x51/0x70
  do_syscall_64+0x91/0xb47
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Since only the read is operating as lockless, it could introduce a logic
bug in unix_recvq_full() due to the load tearing. Fix it by adding
a lockless variant of skb_queue_len() and unix_recvq_full() where
READ_ONCE() is on the read while WRITE_ONCE() is on the write similar to
the commit d7d16a89 ("net: add skb_queue_empty_lockless()").
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move rx_dropped and rx_errors counters in mvneta_pcpu_stats in order to
avoid possible races updating statistics

Fixes: 562e2f46 ("net: mvneta: Improve the buffer allocation method for SWBM")
Fixes: dc35a10f ("net: mvneta: bm: add support for hardware buffer management")
Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Added debugfs entry to show the tls stats.
Signed-off-by: Devulapally Shiva Krishna <shiva@chelsio.com>
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Turns out that when we accept a new subflow, the newly created
inet_sk(tcp_sk)->pinet6 points at the ipv6_pinfo structure of the
listener socket.

This wasn't caught by the selftest because it closes the accepted fd
before the listening one.

adding a close(listenfd) after accept returns is enough:
 BUG: KASAN: use-after-free in inet6_getname+0x6ba/0x790
 Read of size 1 at addr ffff88810e310866 by task mptcp_connect/2518
 Call Trace:
  inet6_getname+0x6ba/0x790
  __sys_getpeername+0x10b/0x250
  __x64_sys_getpeername+0x6f/0xb0

also alter test program to exercise this.
Reported-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit cedeac9d ("qed: Add support for Timestamping the unicast
PTP packets.") handles the timestamping of L4 ptp packets only.
This patch adds driver changes to detect/timestamp both L2/L4 unicast
PTP packets.

Fixes: cedeac9d ("qed: Add support for Timestamping the unicast PTP packets.")
Signed-off-by: Sudarsana Reddy Kalluru <skalluru@marvell.com>
Signed-off-by: Ariel Elior <aelior@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Harini Katakam says:

====================
macb: TSO bug fixes

An IP errata was recently discovered when testing TSO enabled versions
with perf test tools where a false amba error is reported by the IP.
Some ways to reproduce would be to use iperf or applications with payload
descriptor sizes very close to 16K. Once the error is observed TXERR (or
bit 6 of ISR) will be constantly triggered leading to a series of tx path
error handling and clean up. Workaround the same by limiting this size to
0x3FC0 as recommended by Cadence. There was no performance impact on 1G
system that I tested with.

Note on patch 1: The alignment code may be unused but leaving it there
in case anyone is using UFO.

Added Fixes tag to patch 1.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

GEM_MAX_TX_LEN currently resolves to 0x3FF8 for any IP version supporting
TSO with full 14bits of length field in payload descriptor. But an IP
errata causes false amba_error (bit 6 of ISR) when length in payload
descriptors is specified above 16387. The error occurs because the DMA
falsely concludes that there is not enough space in SRAM for incoming
payload. These errors were observed continuously under stress of large
packets using iperf on a version where SRAM was 16K for each queue. This
errata will be documented shortly and affects all versions since TSO
functionality was added. Hence limit the max length to 0x3FC0 (rounded).
Signed-off-by: Harini Katakam <harini.katakam@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The IP TSO implementation does NOT require the length to be a
multiple of 8. That is only a requirement for UFO as per IP
documentation. Hence, exit macb_features_check function in the
beginning if the protocol is not UDP. Only when it is UDP,
proceed further to the alignment checks. Update comments to
reflect the same. Also remove dead code checking for protocol
TCP when calculating header length.

Fixes: 1629dd4f ("cadence: Add LSO support.")
Signed-off-by: Harini Katakam <harini.katakam@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot managed to send an IPX packet through bond_alb_xmit()
and af_packet and triggered a use-after-free.

First, bond_alb_xmit() was using ipx_hdr() helper to reach
the IPX header, but ipx_hdr() was using the transport offset
instead of the network offset. In the particular syzbot
report transport offset was 0xFFFF

This patch removes ipx_hdr() since it was only (mis)used from bonding.

Then we need to make sure IPv4/IPv6/IPX headers are pulled
in skb->head before dereferencing anything.

BUG: KASAN: use-after-free in bond_alb_xmit+0x153a/0x1590 drivers/net/bonding/bond_alb.c:1452
Read of size 2 at addr ffff8801ce56dfff by task syz-executor.2/18108
 (if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) ...)

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 [<ffffffff8441fc42>] __dump_stack lib/dump_stack.c:17 [inline]
 [<ffffffff8441fc42>] dump_stack+0x14d/0x20b lib/dump_stack.c:53
 [<ffffffff81a7dec4>] print_address_description+0x6f/0x20b mm/kasan/report.c:282
 [<ffffffff81a7e0ec>] kasan_report_error mm/kasan/report.c:380 [inline]
 [<ffffffff81a7e0ec>] kasan_report mm/kasan/report.c:438 [inline]
 [<ffffffff81a7e0ec>] kasan_report.cold+0x8c/0x2a0 mm/kasan/report.c:422
 [<ffffffff81a7dc4f>] __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:469
 [<ffffffff82c8c00a>] bond_alb_xmit+0x153a/0x1590 drivers/net/bonding/bond_alb.c:1452
 [<ffffffff82c60c74>] __bond_start_xmit drivers/net/bonding/bond_main.c:4199 [inline]
 [<ffffffff82c60c74>] bond_start_xmit+0x4f4/0x1570 drivers/net/bonding/bond_main.c:4224
 [<ffffffff83baa558>] __netdev_start_xmit include/linux/netdevice.h:4525 [inline]
 [<ffffffff83baa558>] netdev_start_xmit include/linux/netdevice.h:4539 [inline]
 [<ffffffff83baa558>] xmit_one net/core/dev.c:3611 [inline]
 [<ffffffff83baa558>] dev_hard_start_xmit+0x168/0x910 net/core/dev.c:3627
 [<ffffffff83bacf35>] __dev_queue_xmit+0x1f55/0x33b0 net/core/dev.c:4238
 [<ffffffff83bae3a8>] dev_queue_xmit+0x18/0x20 net/core/dev.c:4278
 [<ffffffff84339189>] packet_snd net/packet/af_packet.c:3226 [inline]
 [<ffffffff84339189>] packet_sendmsg+0x4919/0x70b0 net/packet/af_packet.c:3252
 [<ffffffff83b1ac0c>] sock_sendmsg_nosec net/socket.c:673 [inline]
 [<ffffffff83b1ac0c>] sock_sendmsg+0x12c/0x160 net/socket.c:684
 [<ffffffff83b1f5a2>] __sys_sendto+0x262/0x380 net/socket.c:1996
 [<ffffffff83b1f700>] SYSC_sendto net/socket.c:2008 [inline]
 [<ffffffff83b1f700>] SyS_sendto+0x40/0x60 net/socket.c:2004

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

commit fdd41ec2 ("devlink: Return right error code in case of errors
for region read") modified the region read code to report errors
properly in unexpected cases.

In the case where the start_offset and ret_offset match, it unilaterally
converted this into an error. This causes an issue for the "dump"
version of the command. In this case, the devlink region dump will
always report an invalid argument:

000000000000ffd0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
000000000000ffe0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
devlink answers: Invalid argument
000000000000fff0 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

This occurs because the expected flow for the dump is to return 0 after
there is no further data.

The simplest fix would be to stop converting the error code to -EINVAL
if start_offset == ret_offset. However, avoid unnecessary work by
checking for when start_offset is larger than the region size and
returning 0 upfront.

Fixes: fdd41ec2 ("devlink: Return right error code in case of errors for region read")
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The receive frame length calculation uses a wrong mask to calculate the
length of the received frames.

Per spec table 4-1 the length is contained in the FL (Frame Length)
field in bits 30:16.

This didn't show up as an issue so far since frames were limited to
1500 bytes which falls within the 11 bit window.
Signed-off-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jason A. Donenfeld says:

====================
wireguard fixes for 5.6-rc1

Here are fixes for WireGuard before 5.6-rc1 is tagged. It includes:

1) A fix for a UaF (caused by kmalloc failing during a very small
   allocation) that syzkaller found, from Eric Dumazet.

2) A fix for a deadlock that syzkaller found, along with an additional
   selftest to ensure that the bug fix remains correct, from me.

3) Two little fixes/cleanups to the selftests from Krzysztof Kozlowski
   and me.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Without this, we wind up proceeding too early sometimes when the
previous process has just used the same listening port. So, we tie the
listening socket query to the specific pid we're interested in.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

CONFIG_ENABLE_WARN_DEPRECATED is gone since commit 771c0353
("deprecate the '__deprecated' attribute warnings entirely and for
good").
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ensure that peers with low order points are ignored, both in the case
where we already have a device private key and in the case where we do
not. This adds points that naturally give a zero output.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Our static-static calculation returns a failure if the public key is of
low order. We check for this when peers are added, and don't allow them
to be added if they're low order, except in the case where we haven't
yet been given a private key. In that case, we would defer the removal
of the peer until we're given a private key, since at that point we're
doing new static-static calculations which incur failures we can act on.
This meant, however, that we wound up removing peers rather late in the
configuration flow.

Syzkaller points out that peer_remove calls flush_workqueue, which in
turn might then wait for sending a handshake initiation to complete.
Since handshake initiation needs the static identity lock, holding the
static identity lock while calling peer_remove can result in a rare
deadlock. We have precisely this case in this situation of late-stage
peer removal based on an invalid public key. We can't drop the lock when
removing, because then incoming handshakes might interact with a bogus
static-static calculation.

While the band-aid patch for this would involve breaking up the peer
removal into two steps like wg_peer_remove_all does, in order to solve
the locking issue, there's actually a much more elegant way of fixing
this:

If the static-static calculation succeeds with one private key, it
*must* succeed with all others, because all 32-byte strings map to valid
private keys, thanks to clamping. That means we can get rid of this
silly dance and locking headaches of removing peers late in the
configuration flow, and instead just reject them early on, regardless of
whether the device has yet been assigned a private key. For the case
where the device doesn't yet have a private key, we safely use zeros
just for the purposes of checking for low order points by way of
checking the output of the calculation.

The following PoC will trigger the deadlock:

ip link add wg0 type wireguard
ip addr add 10.0.0.1/24 dev wg0
ip link set wg0 up
ping -f 10.0.0.2 &
while true; do
        wg set wg0 private-key /dev/null peer AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA= allowed-ips 10.0.0.0/24 endpoint 10.0.0.3:1234
        wg set wg0 private-key <(echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=)
done

[    0.949105] ======================================================
[    0.949550] WARNING: possible circular locking dependency detected
[    0.950143] 5.5.0-debug+ #18 Not tainted
[    0.950431] ------------------------------------------------------
[    0.950959] wg/89 is trying to acquire lock:
[    0.951252] ffff8880333e2128 ((wq_completion)wg-kex-wg0){+.+.}, at: flush_workqueue+0xe3/0x12f0
[    0.951865]
[    0.951865] but task is already holding lock:
[    0.952280] ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.953011]
[    0.953011] which lock already depends on the new lock.
[    0.953011]
[    0.953651]
[    0.953651] the existing dependency chain (in reverse order) is:
[    0.954292]
[    0.954292] -> #2 (&wg->static_identity.lock){++++}:
[    0.954804]        lock_acquire+0x127/0x350
[    0.955133]        down_read+0x83/0x410
[    0.955428]        wg_noise_handshake_create_initiation+0x97/0x700
[    0.955885]        wg_packet_send_handshake_initiation+0x13a/0x280
[    0.956401]        wg_packet_handshake_send_worker+0x10/0x20
[    0.956841]        process_one_work+0x806/0x1500
[    0.957167]        worker_thread+0x8c/0xcb0
[    0.957549]        kthread+0x2ee/0x3b0
[    0.957792]        ret_from_fork+0x24/0x30
[    0.958234]
[    0.958234] -> #1 ((work_completion)(&peer->transmit_handshake_work)){+.+.}:
[    0.958808]        lock_acquire+0x127/0x350
[    0.959075]        process_one_work+0x7ab/0x1500
[    0.959369]        worker_thread+0x8c/0xcb0
[    0.959639]        kthread+0x2ee/0x3b0
[    0.959896]        ret_from_fork+0x24/0x30
[    0.960346]
[    0.960346] -> #0 ((wq_completion)wg-kex-wg0){+.+.}:
[    0.960945]        check_prev_add+0x167/0x1e20
[    0.961351]        __lock_acquire+0x2012/0x3170
[    0.961725]        lock_acquire+0x127/0x350
[    0.961990]        flush_workqueue+0x106/0x12f0
[    0.962280]        peer_remove_after_dead+0x160/0x220
[    0.962600]        wg_set_device+0xa24/0xcc0
[    0.962994]        genl_rcv_msg+0x52f/0xe90
[    0.963298]        netlink_rcv_skb+0x111/0x320
[    0.963618]        genl_rcv+0x1f/0x30
[    0.963853]        netlink_unicast+0x3f6/0x610
[    0.964245]        netlink_sendmsg+0x700/0xb80
[    0.964586]        __sys_sendto+0x1dd/0x2c0
[    0.964854]        __x64_sys_sendto+0xd8/0x1b0
[    0.965141]        do_syscall_64+0x90/0xd9a
[    0.965408]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.965769]
[    0.965769] other info that might help us debug this:
[    0.965769]
[    0.966337] Chain exists of:
[    0.966337]   (wq_completion)wg-kex-wg0 --> (work_completion)(&peer->transmit_handshake_work) --> &wg->static_identity.lock
[    0.966337]
[    0.967417]  Possible unsafe locking scenario:
[    0.967417]
[    0.967836]        CPU0                    CPU1
[    0.968155]        ----                    ----
[    0.968497]   lock(&wg->static_identity.lock);
[    0.968779]                                lock((work_completion)(&peer->transmit_handshake_work));
[    0.969345]                                lock(&wg->static_identity.lock);
[    0.969809]   lock((wq_completion)wg-kex-wg0);
[    0.970146]
[    0.970146]  *** DEADLOCK ***
[    0.970146]
[    0.970531] 5 locks held by wg/89:
[    0.970908]  #0: ffffffff827433c8 (cb_lock){++++}, at: genl_rcv+0x10/0x30
[    0.971400]  #1: ffffffff82743480 (genl_mutex){+.+.}, at: genl_rcv_msg+0x642/0xe90
[    0.971924]  #2: ffffffff827160c0 (rtnl_mutex){+.+.}, at: wg_set_device+0x9f/0xcc0
[    0.972488]  #3: ffff888032819de0 (&wg->device_update_lock){+.+.}, at: wg_set_device+0xb0/0xcc0
[    0.973095]  #4: ffff888032819bc0 (&wg->static_identity.lock){++++}, at: wg_set_device+0x95d/0xcc0
[    0.973653]
[    0.973653] stack backtrace:
[    0.973932] CPU: 1 PID: 89 Comm: wg Not tainted 5.5.0-debug+ #18
[    0.974476] Call Trace:
[    0.974638]  dump_stack+0x97/0xe0
[    0.974869]  check_noncircular+0x312/0x3e0
[    0.975132]  ? print_circular_bug+0x1f0/0x1f0
[    0.975410]  ? __kernel_text_address+0x9/0x30
[    0.975727]  ? unwind_get_return_address+0x51/0x90
[    0.976024]  check_prev_add+0x167/0x1e20
[    0.976367]  ? graph_lock+0x70/0x160
[    0.976682]  __lock_acquire+0x2012/0x3170
[    0.976998]  ? register_lock_class+0x1140/0x1140
[    0.977323]  lock_acquire+0x127/0x350
[    0.977627]  ? flush_workqueue+0xe3/0x12f0
[    0.977890]  flush_workqueue+0x106/0x12f0
[    0.978147]  ? flush_workqueue+0xe3/0x12f0
[    0.978410]  ? find_held_lock+0x2c/0x110
[    0.978662]  ? lock_downgrade+0x6e0/0x6e0
[    0.978919]  ? queue_rcu_work+0x60/0x60
[    0.979166]  ? netif_napi_del+0x151/0x3b0
[    0.979501]  ? peer_remove_after_dead+0x160/0x220
[    0.979871]  peer_remove_after_dead+0x160/0x220
[    0.980232]  wg_set_device+0xa24/0xcc0
[    0.980516]  ? deref_stack_reg+0x8e/0xc0
[    0.980801]  ? set_peer+0xe10/0xe10
[    0.981040]  ? __ww_mutex_check_waiters+0x150/0x150
[    0.981430]  ? __nla_validate_parse+0x163/0x270
[    0.981719]  ? genl_family_rcv_msg_attrs_parse+0x13f/0x310
[    0.982078]  genl_rcv_msg+0x52f/0xe90
[    0.982348]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.982690]  ? register_lock_class+0x1140/0x1140
[    0.983049]  netlink_rcv_skb+0x111/0x320
[    0.983298]  ? genl_family_rcv_msg_attrs_parse+0x310/0x310
[    0.983645]  ? netlink_ack+0x880/0x880
[    0.983888]  genl_rcv+0x1f/0x30
[    0.984168]  netlink_unicast+0x3f6/0x610
[    0.984443]  ? netlink_detachskb+0x60/0x60
[    0.984729]  ? find_held_lock+0x2c/0x110
[    0.984976]  netlink_sendmsg+0x700/0xb80
[    0.985220]  ? netlink_broadcast_filtered+0xa60/0xa60
[    0.985533]  __sys_sendto+0x1dd/0x2c0
[    0.985763]  ? __x64_sys_getpeername+0xb0/0xb0
[    0.986039]  ? sockfd_lookup_light+0x17/0x160
[    0.986397]  ? __sys_recvmsg+0x8c/0xf0
[    0.986711]  ? __sys_recvmsg_sock+0xd0/0xd0
[    0.987018]  __x64_sys_sendto+0xd8/0x1b0
[    0.987283]  ? lockdep_hardirqs_on+0x39b/0x5a0
[    0.987666]  do_syscall_64+0x90/0xd9a
[    0.987903]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[    0.988223] RIP: 0033:0x7fe77c12003e
[    0.988508] Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 4
[    0.989666] RSP: 002b:00007fffada2ed58 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[    0.990137] RAX: ffffffffffffffda RBX: 00007fe77c159d48 RCX: 00007fe77c12003e
[    0.990583] RDX: 0000000000000040 RSI: 000055fd1d38e020 RDI: 0000000000000004
[    0.991091] RBP: 000055fd1d38e020 R08: 000055fd1cb63358 R09: 000000000000000c
[    0.991568] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000002c
[    0.992014] R13: 0000000000000004 R14: 000055fd1d38e020 R15: 0000000000000001
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the unlikely case a new node could not be allocated, we need to
remove @newnode from @peer->allowedips_list before freeing it.

syzbot reported:

BUG: KASAN: use-after-free in __list_del_entry_valid+0xdc/0xf5 lib/list_debug.c:54
Read of size 8 at addr ffff88809881a538 by task syz-executor.4/30133

CPU: 0 PID: 30133 Comm: syz-executor.4 Not tainted 5.5.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 __list_del_entry_valid+0xdc/0xf5 lib/list_debug.c:54
 __list_del_entry include/linux/list.h:132 [inline]
 list_del include/linux/list.h:146 [inline]
 root_remove_peer_lists+0x24f/0x4b0 drivers/net/wireguard/allowedips.c:65
 wg_allowedips_free+0x232/0x390 drivers/net/wireguard/allowedips.c:300
 wg_peer_remove_all+0xd5/0x620 drivers/net/wireguard/peer.c:187
 wg_set_device+0xd01/0x1350 drivers/net/wireguard/netlink.c:542
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:672
 ____sys_sendmsg+0x753/0x880 net/socket.c:2343
 ___sys_sendmsg+0x100/0x170 net/socket.c:2397
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45b399
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f99a9bcdc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f99a9bce6d4 RCX: 000000000045b399
RDX: 0000000000000000 RSI: 0000000020001340 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00000000000009ba R14: 00000000004cb2b8 R15: 0000000000000009

Allocated by task 30103:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527
 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:670 [inline]
 add+0x70a/0x1970 drivers/net/wireguard/allowedips.c:236
 wg_allowedips_insert_v4+0xf6/0x160 drivers/net/wireguard/allowedips.c:320
 set_allowedip drivers/net/wireguard/netlink.c:343 [inline]
 set_peer+0xfb9/0x1150 drivers/net/wireguard/netlink.c:468
 wg_set_device+0xbd4/0x1350 drivers/net/wireguard/netlink.c:591
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:672
 ____sys_sendmsg+0x753/0x880 net/socket.c:2343
 ___sys_sendmsg+0x100/0x170 net/socket.c:2397
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 30103:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:335 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x10a/0x2c0 mm/slab.c:3757
 add+0x12d2/0x1970 drivers/net/wireguard/allowedips.c:266
 wg_allowedips_insert_v4+0xf6/0x160 drivers/net/wireguard/allowedips.c:320
 set_allowedip drivers/net/wireguard/netlink.c:343 [inline]
 set_peer+0xfb9/0x1150 drivers/net/wireguard/netlink.c:468
 wg_set_device+0xbd4/0x1350 drivers/net/wireguard/netlink.c:591
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x67d/0xea0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 genl_rcv+0x29/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:672
 ____sys_sendmsg+0x753/0x880 net/socket.c:2343
 ___sys_sendmsg+0x100/0x170 net/socket.c:2397
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88809881a500
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 56 bytes inside of
 64-byte region [ffff88809881a500, ffff88809881a540)
The buggy address belongs to the page:
page:ffffea0002620680 refcount:1 mapcount:0 mapping:ffff8880aa400380 index:0x0
raw: 00fffe0000000200 ffffea000250b748 ffffea000254bac8 ffff8880aa400380
raw: 0000000000000000 ffff88809881a000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809881a400: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88809881a480: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff88809881a500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                        ^
 ffff88809881a580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88809881a600: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc

Fixes: e7096c13 ("net: WireGuard secure network tunnel")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: wireguard@lists.zx2c4.com
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>