This patch fixed 2 issues with the usage of skb_cow in LAPB drivers
"lapbether" and "hdlc_x25":

1) After skb_cow fails, kfree_skb should be called to drop a reference
to the skb. But in both drivers, kfree_skb is not called.

2) skb_cow should be called before skb_push so that is can ensure the
safety of skb_push. But in "lapbether", it is incorrectly called after
skb_push.

More details about these 2 issues:

1) The behavior of calling kfree_skb on failure is also the behavior of
netif_rx, which is called by this function with "return netif_rx(skb);".
So this function should follow this behavior, too.

2) In "lapbether", skb_cow is called after skb_push. This results in 2
logical issues:
   a) skb_push is not protected by skb_cow;
   b) An extra headroom of 1 byte is ensured after skb_push. This extra
      headroom has no use in this function. It also has no use in the
      upper-layer function that this function passes the skb to
      (x25_lapb_receive_frame in net/x25/x25_dev.c).
So logically skb_cow should instead be called before skb_push.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

IRQs are disabled when freeing skbs in input queue.
Use the IRQ safe variant to free skbs here.

Fixes: 145dd5f9 ("net: flush the softnet backlog in process context")
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

We have to detach sock from socket in qrtr_release(),
otherwise skb->sk may still reference to this socket
when the skb is released in tun->queue, particularly
sk->sk_wq still points to &sock->wq, which leads to
a UAF.

Reported-and-tested-by: syzbot+6720d64f31c081c2f708@syzkaller.appspotmail.com
Fixes: 28fb4e59 ("net: qrtr: Expose tunneling endpoint to user space")
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'wireless-drivers-2020-07-24' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers

Kalle Valo says:

====================
wireless-drivers fixes for v5.8

Second set of fixes for v5.8, and hopefully also the last. Three
important regressions fixed.

ath9k

* fix a regression which broke support for all ath9k usb devices

ath10k

* fix a regression which broke support for all QCA4019 AHB devices

iwlwifi

* fix a regression which broke support for some Killer Wireless-AC 1550 cards
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

There's a potential race in xennet_remove(); this is what the driver is
doing upon unregistering a network device:

  1. state = read bus state
  2. if state is not "Closed":
  3.    request to set state to "Closing"
  4.    wait for state to be set to "Closing"
  5.    request to set state to "Closed"
  6.    wait for state to be set to "Closed"

If the state changes to "Closed" immediately after step 1 we are stuck
forever in step 4, because the state will never go back from "Closed" to
"Closing".

Make sure to check also for state == "Closed" in step 4 to prevent the
deadlock.

Also add a 5 sec timeout any time we wait for the bus state to change,
to avoid getting stuck forever in wait_event().
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

I noticed that touching linux/rhashtable.h causes lib/vsprintf.c to
be rebuilt.  This dependency came through a bogus inclusion in the
file net/flow_offload.h.  This patch moves it to the right place.

This patch also removes a lingering rhashtable inclusion in cls_api
created by the same commit.

Fixes: 4e481908 ("flow_offload: move tc indirect block to...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains Netfilter/IPVS fixes for net:

1) Fix NAT hook deletion when table is dormant, from Florian Westphal.

2) Fix IPVS sync stalls, from guodeqing.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

geneve_nl2info() sets 'df' conditionally, so we have to
initialize it by copying the value from existing geneve
device in geneve_changelink().

Fixes: 56c09de3 ("geneve: allow changing DF behavior after creation")
Reported-by: syzbot+7ebc2e088af5e4c0c9fa@syzkaller.appspotmail.com
Cc: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Very similar to commit 544f287b
("bonding: check error value of register_netdevice() immediately"),
we should immediately check the return value of register_netdevice()
before doing anything else.

Fixes: 005db31d ("bonding: set carrier off for devices created through netlink")
Reported-and-tested-by: syzbot+bbc3a11c4da63c1b74d6@syzkaller.appspotmail.com
Cc: Beniamino Galvani <bgalvani@redhat.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Previously TLP may send multiple probes of new data in one
flight. This happens when the sender is cwnd limited. After the
initial TLP containing new data is sent, the sender receives another
ACK that acks partial inflight.  It may re-arm another TLP timer
to send more, if no further ACK returns before the next TLP timeout
(PTO) expires. The sender may send in theory a large amount of TLP
until send queue is depleted. This only happens if the sender sees
such irregular uncommon ACK pattern. But it is generally undesirable
behavior during congestion especially.

The original TLP design restrict only one TLP probe per inflight as
published in "Reducing Web Latency: the Virtue of Gentle Aggression",
SIGCOMM 2013. This patch changes TLP to send at most one probe
per inflight.

Note that if the sender is app-limited, TLP retransmits old data
and did not have this issue.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb06 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffa ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the implementation of uld_send(), the skb is consumed on all
execution paths except one. Release skb when returning NET_XMIT_DROP.
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch fixes PTP on AQC10X.
PTP support on AQC10X requires FW involvement and FW configures the
TPS data arb mode itself.
So we must make sure driver doesn't touch TPS data arb mode on AQC10x
if PTP is enabled. Otherwise, there are no timestamps even though
packets are flowing.

Fixes: 2deac71a ("net: atlantic: QoS implementation: min_rate")
Signed-off-by: Egor Pomozov <epomozov@marvell.com>
Signed-off-by: Mark Starovoytov <mstarovoitov@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Checks on `addr_len` and `usax->sax25_ndigis` are insufficient.
ax25_sendmsg() can go out of bounds when `usax->sax25_ndigis` equals to 7
or 8. Fix it.

It is safe to remove `usax->sax25_ndigis > AX25_MAX_DIGIS`, since
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Xin Long says:

====================
sctp: shrink stream outq in the right place

Patch 1 is an improvement, and Patch 2 is a bug fix.
====================
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When adding a stream with stream reconf, the new stream firstly is in
CLOSED state but new out chunks can still be enqueued. Then once gets
the confirmation from the peer, the state will change to OPEN.

However, if the peer denies, it needs to roll back the stream. But when
doing that, it only sets the stream outcnt back, and the chunks already
in the new stream don't get purged. It caused these chunks can still be
dequeued in sctp_outq_dequeue_data().

As its stream is still in CLOSE, the chunk will be enqueued to the head
again by sctp_outq_head_data(). This chunk will never be sent out, and
the chunks after it can never be dequeued. The assoc will be 'hung' in
a dead loop of sending this chunk.

To fix it, this patch is to purge these chunks already in the new
stream by calling sctp_stream_shrink_out() when failing to do the
addstream reconf.

Fixes: 11ae76e6 ("sctp: implement receiver-side procedures for the Reconf Response Parameter")
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It's not necessary to go list_for_each for outq->out_chunk_list
when new outcnt >= old outcnt, as no chunk with higher sid than
new (outcnt - 1) exists in the outqueue.

While at it, also move the list_for_each code in a new function
sctp_stream_shrink_out(), which will be used in the next patch.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Checks on `addr_len` and `fsa->fsa_ax25.sax25_ndigis` are insufficient.
ax25_connect() can go out of bounds when `fsa->fsa_ax25.sax25_ndigis`
equals to 7 or 8. Fix it.

This issue has been reported as a KMSAN uninit-value bug, because in such
a case, ax25_connect() reaches into the uninitialized portion of the
`struct sockaddr_storage` statically allocated in __sys_connect().

It is safe to remove `fsa->fsa_ax25.sax25_ndigis > AX25_MAX_DIGIS` because
`addr_len` is guaranteed to be less than or equal to
`sizeof(struct full_sockaddr_ax25)`.

Reported-by: syzbot+c82752228ed975b0a623@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=55ef9d629f3b3d7d70b69558015b63b48d01af66Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For ENETC ports that register an external MDIO bus,
the bus doesn't get removed on the error bailout path
of enetc_pf_probe().

This issue became much more visible after recent:
commit 07095c02 ("net: enetc: Use DT protocol information to set up the ports")
Before this commit, one could make probing fail on the error
path only by having register_netdev() fail, which is unlikely.
But after this commit, because it moved the enetc_of_phy_get()
call up in the probing sequence, now we can trigger an mdiobus_free()
bug just by forcing enetc_alloc_msix() to return error, i.e. with the
'pci=nomsi' kernel bootarg (since ENETC relies on MSI support to work),
as the calltrace below shows:

kernel BUG at /home/eiz/work/enetc/net/drivers/net/phy/mdio_bus.c:648!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[...]
Hardware name: LS1028A RDB Board (DT)
pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--)
pc : mdiobus_free+0x50/0x58
lr : devm_mdiobus_free+0x14/0x20
[...]
Call trace:
 mdiobus_free+0x50/0x58
 devm_mdiobus_free+0x14/0x20
 release_nodes+0x138/0x228
 devres_release_all+0x38/0x60
 really_probe+0x1c8/0x368
 driver_probe_device+0x5c/0xc0
 device_driver_attach+0x74/0x80
 __driver_attach+0x8c/0xd8
 bus_for_each_dev+0x7c/0xd8
 driver_attach+0x24/0x30
 bus_add_driver+0x154/0x200
 driver_register+0x64/0x120
 __pci_register_driver+0x44/0x50
 enetc_pf_driver_init+0x24/0x30
 do_one_initcall+0x60/0x1c0
 kernel_init_freeable+0x1fc/0x274
 kernel_init+0x14/0x110
 ret_from_fork+0x10/0x34

Fixes: ebfcb23d ("enetc: Add ENETC PF level external MDIO support")
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently drive supports taprio offload which is a tc feature offloaded
to cpsw hardware. So driver has to set the hw feature flag, NETIF_F_HW_TC
in the net device to be compliant. This patch adds the flag.

Fixes: 8127224c ("ethernet: ti: am65-cpsw-qos: add TAPRIO offload support")
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When regmap_update_bits failed in ave_init(), calls of the functions
reset_control_assert() and clk_disable_unprepare() were missed.
Add goto out_reset_assert to do this.

Fixes: 57878f2f ("net: ethernet: ave: add support for phy-mode setting of system controller")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Reviewed-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This driver is not working because of problems of its receiving code.
This patch fixes it to make it work.

When the driver receives an LAPB frame, it should first pass the frame
to the LAPB module to process. After processing, the LAPB module passes
the data (the packet) back to the driver, the driver should then add a
one-byte pseudo header and pass the data to upper layers.

The changes to the "x25_asy_bump" function and the
"x25_asy_data_indication" function are to correctly implement this
procedure.

Also, the "x25_asy_unesc" function ignores any frame that is shorter
than 3 bytes. However the shortest frames are 2-byte long. So we need
to change it to allow 2-byte frames to pass.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Reviewed-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

The sync_thread_backup only checks sk_receive_queue is empty or not,
there is a situation which cannot sync the connection entries when
sk_receive_queue is empty and sk_rmem_alloc is larger than sk_rcvbuf,
the sync packets are dropped in __udp_enqueue_schedule_skb, this is
because the packets in reader_queue is not read, so the rmem is
not reclaimed.

Here I add the check of whether the reader_queue of the udp sock is
empty or not to solve this problem.

Fixes: 2276f58a ("udp: use a separate rx queue for packet reception")
Reported-by: zhouxudong <zhouxudong8@huawei.com>
Signed-off-by: guodeqing <geffrey.guo@huawei.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

According to 'man 8 ip-netns', if `ip netns identify` returns an empty string,
there's no net namespace associated with current PID: fix the net ns entrance
logic.
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexander Lobakin says:

====================
qed: suppress irrelevant error messages on HW init

This raises the verbosity level of several error/warning messages on
driver/module initialization, most of which are false-positives, and
the one actively spamming the log for no reason.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

It was found that qed_pglueb_rbc_attn_handler() can produce a lot of
false-positive error detections on driver load/reload (especially after
crashes/recoveries) and spam the kernel log:

[    4.958275] [qed_pglueb_rbc_attn_handler:324()]ICPL error - 00d00ff0
[ 2079.146764] [qed_pglueb_rbc_attn_handler:324()]ICPL error - 00d80ff0
[ 2116.374631] [qed_pglueb_rbc_attn_handler:324()]ICPL error - 00d80ff0
[ 2135.250564] [qed_pglueb_rbc_attn_handler:324()]ICPL error - 00d80ff0
[...]

Reduce the logging level of two false-positive prone error messages from
notice to verbose on initialization (only) to not mix it with real error
attentions while debugging.

Fixes: 666db486 ("qed: Revise load sequence to avoid PCI errors")
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change the verbosity of the "don't support RoCE & iWARP simultaneously"
warning to debug level to stop flooding on driver/hardware initialization:

[    4.783230] qede 01:00.00: Storm FW 8.37.7.0, Management FW 8.52.9.0
[MBI 15.10.6] [eth0]
[    4.810020] [qed_rdma_set_pf_params:2076()]Current day drivers don't
support RoCE & iWARP simultaneously on the same PF. Default to RoCE-only
[    4.861186] qede 01:00.01: Storm FW 8.37.7.0, Management FW 8.52.9.0
[MBI 15.10.6] [eth1]
[    4.893311] [qed_rdma_set_pf_params:2076()]Current day drivers don't
support RoCE & iWARP simultaneously on the same PF. Default to RoCE-only
[    5.181713] qede a1:00.00: Storm FW 8.37.7.0, Management FW 8.52.9.0
[MBI 15.10.6] [eth2]
[    5.224740] [qed_rdma_set_pf_params:2076()]Current day drivers don't
support RoCE & iWARP simultaneously on the same PF. Default to RoCE-only
[    5.276449] qede a1:00.01: Storm FW 8.37.7.0, Management FW 8.52.9.0
[MBI 15.10.6] [eth3]
[    5.318671] [qed_rdma_set_pf_params:2076()]Current day drivers don't
support RoCE & iWARP simultaneously on the same PF. Default to RoCE-only
[    5.369548] qede a1:00.02: Storm FW 8.37.7.0, Management FW 8.52.9.0
[MBI 15.10.6] [eth4]
[    5.411645] [qed_rdma_set_pf_params:2076()]Current day drivers don't
support RoCE & iWARP simultaneously on the same PF. Default to RoCE-only

Fixes: e0a8f9de ("qed: Add iWARP enablement support")
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the nsim_create(), rtnl_lock() is called before nsim_bpf_init().
If nsim_bpf_init() is failed, rtnl_unlock() should be called,
but it isn't called.
So, unbalanced locking would occur.

Fixes: e05b2d14 ("netdevsim: move netdev creation/destruction to dev probe")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

When doing "ip link set dev ... up" for a ksz9477 backed link,
ksz9477_phy_setup is called and it calls phy_remove_link_mode to remove
1000baseT HDX. During phy_remove_link_mode, phy_advertise_supported is
called. Doing so reverts any previous change to advertised link modes
e.g. using a udevd .link file.

phy_remove_link_mode is not meant to be used while opening a link and
should be called during phy probe when the link is not yet available to
userspace.

Therefore move the phy_remove_link_mode calls into
ksz9477_switch_register. It indirectly calls dsa_register_switch, which
creates the relevant struct phy_devices and we update the link modes
right after that. At that time dev->features is already initialized by
ksz9477_switch_detect.

Remove phy_setup from ksz_dev_ops as no users remain.

Link: https://lore.kernel.org/netdev/20200715192722.GD1256692@lunn.ch/
Fixes: 42fc6a4c ("net: dsa: microchip: prepare PHY for proper advertisement")
Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Huazhong Tan says:

====================
net: hns3: fixes for -net

There are some bugfixes for the HNS3 ethernet driver.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, PF queries the MAC link status per second by calling
function hclge_get_mac_link_status(). It return the error code
when failed to send cmdq command to firmware. It's incorrect,
because this return value is used as the MAC link status, which
0 means link down, and none-zero means link up. So fixes it.

Fixes: 46a3df9f ("net: hns3: Add HNS3 Acceleration Engine & Compatibility Layer Support")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Huazhong tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The content of the TX desc is automatically cleared by the HW
when the HW has sent out the packet to the wire. When desc filling
fails in hns3_nic_net_xmit(), it will call hns3_clear_desc() to do
the error handling, which miss zeroing of the TX desc and the
checking if a unmapping is needed.

So add the zeroing and checking in hns3_clear_desc() to avoid the
above problem. Also add DESC_TYPE_UNKNOWN to indicate the info in
desc_cb is not valid, because hns3_nic_reclaim_desc() may treat
the desc_cb->type of zero as packet and add to the sent pkt
statistics accordingly.

Fixes: 76ad4f0e ("net: hns3: Add support of HNS3 Ethernet Driver for hip08 SoC")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

With GRO and fraglist support, the SKB can be aggregated to
a total size of 65535, and when that SKB is forwarded through
a bridge, the size of the SKB may be pushed to exceed the size
of 65535 when br_dev_queue_push_xmit() is called.

The max send size of BD supported by the HW is 65535, when a SKB
with a headlen of over 65535 is sent to the driver, the driver
needs to use multi BD to send the linear data, and the send size
of the last BD is calculated incorrectly by the driver who is
using '&' operation, which causes a TX error.

Use '%' operation to fix this problem.

Fixes: 3fe13ed9 ("net: hns3: avoid mult + div op in critical data path")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a big TX buffer is sent using multi BD, the driver maps the
whole TX buffer, and unmaps it using info in desc_cb corresponding
to each BD, but only the info in the desc_cb of first BD is correct,
other info in desc_cb is wrong, which causes TX unmapping problem
when SMMU is on.

Only set the mapping and freeing info in the desc_cb of first BD to
fix this problem, because the TX buffer only need to be unmapped and
freed once.

Fixes: 1e8a7977("net: hns3: add handling for big TX fragment")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huzhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We can't use IS_UDPLITE to replace udp_sk->pcflag when UDPLITE_RECV_CC is
checked.

Fixes: b2bf1e26 ("[UDP]: Clean up for IS_UDPLITE macro")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When I cat 'tx_timeout' by sysfs, it displays as follows. It's better to
add a newline for easy reading.

root@syzkaller:~# cat /sys/devices/virtual/net/lo/queues/tx-0/tx_timeout
0root@syzkaller:~#
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

According to the report of [1], this driver is possible to cause
the following error in ravb_tx_timeout_work().

ravb e6800000.ethernet ethernet: failed to switch device to config mode

This error means that the hardware could not change the state
from "Operation" to "Configuration" while some tx and/or rx queue
are operating. After that, ravb_config() in ravb_dmac_init() will fail,
and then any descriptors will be not allocaled anymore so that NULL
pointer dereference happens after that on ravb_start_xmit().

To fix the issue, the ravb_tx_timeout_work() should check
the return values of ravb_stop_dma() and ravb_dmac_init().
If ravb_stop_dma() fails, ravb_tx_timeout_work() re-enables TX and RX
and just exits. If ravb_dmac_init() fails, just exits.

[1]
https://lore.kernel.org/linux-renesas-soc/20200518045452.2390-1-dirk.behme@de.bosch.com/Reported-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Kuniyuki Iwashima says:

====================
udp: Fix reuseport selection with connected sockets.

This patch set addresses two issues which happen when both connected and
unconnected sockets are in the same UDP reuseport group.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, SO_REUSEPORT does not work well if connected sockets are in a
UDP reuseport group.

Then reuseport_has_conns() returns true and the result of
reuseport_select_sock() is discarded. Also, unconnected sockets have the
same score, hence only does the first unconnected socket in udp_hslot
always receive all packets sent to unconnected sockets.

So, the result of reuseport_select_sock() should be used for load
balancing.

The noteworthy point is that the unconnected sockets placed after
connected sockets in sock_reuseport.socks will receive more packets than
others because of the algorithm in reuseport_select_sock().

    index | connected | reciprocal_scale | result
    ---------------------------------------------
    0     | no        | 20%              | 40%
    1     | no        | 20%              | 20%
    2     | yes       | 20%              | 0%
    3     | no        | 20%              | 40%
    4     | yes       | 20%              | 0%

If most of the sockets are connected, this can be a problem, but it still
works better than now.

Fixes: acdcecc6 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn <willemb@google.com>
Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If an unconnected socket in a UDP reuseport group connect()s, has_conns is
set to 1. Then, when a packet is received, udp[46]_lib_lookup2() scans all
sockets in udp_hslot looking for the connected socket with the highest
score.

However, when the number of sockets bound to the port exceeds max_socks,
reuseport_grow() resets has_conns to 0. It can cause udp[46]_lib_lookup2()
to return without scanning all sockets, resulting in that packets sent to
connected sockets may be distributed to unconnected sockets.

Therefore, reuseport_grow() should copy has_conns.

Fixes: acdcecc6 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn <willemb@google.com>
Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>