Commits · 9122a70a6333705c0c35614ddc51c274ed1d3637 · Kirill Smelkov / linux

26 Oct, 2021 2 commits

net: multicast: calculate csum of looped-back and forwarded packets · 9122a70a

Cyril Strejc authored Oct 24, 2021

During a testing of an user-space application which transmits UDP
multicast datagrams and utilizes multicast routing to send the UDP
datagrams out of defined network interfaces, I've found a multicast
router does not fill-in UDP checksum into locally produced, looped-back
and forwarded UDP datagrams, if an original output NIC the datagrams
are sent to has UDP TX checksum offload enabled.

The datagrams are sent malformed out of the NIC the datagrams have been
forwarded to.

It is because:

1. If TX checksum offload is enabled on the output NIC, UDP checksum
   is not calculated by kernel and is not filled into skb data.

2. dev_loopback_xmit(), which is called solely by
   ip_mc_finish_output(), sets skb->ip_summed = CHECKSUM_UNNECESSARY
   unconditionally.

3. Since 35fc92a9 ("[NET]: Allow forwarding of ip_summed except
   CHECKSUM_COMPLETE"), the ip_summed value is preserved during
   forwarding.

4. If ip_summed != CHECKSUM_PARTIAL, checksum is not calculated during
   a packet egress.

The minimum fix in dev_loopback_xmit():

1. Preserves skb->ip_summed CHECKSUM_PARTIAL. This is the
   case when the original output NIC has TX checksum offload enabled.
   The effects are:

     a) If the forwarding destination interface supports TX checksum
        offloading, the NIC driver is responsible to fill-in the
        checksum.

     b) If the forwarding destination interface does NOT support TX
        checksum offloading, checksums are filled-in by kernel before
        skb is submitted to the NIC driver.

     c) For local delivery, checksum validation is skipped as in the
        case of CHECKSUM_UNNECESSARY, thanks to skb_csum_unnecessary().

2. Translates ip_summed CHECKSUM_NONE to CHECKSUM_UNNECESSARY. It
   means, for CHECKSUM_NONE, the behavior is unmodified and is there
   to skip a looped-back packet local delivery checksum validation.
Signed-off-by: Cyril Strejc <cyril.strejc@skoda.cz>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

9122a70a

mlxsw: pci: Recycle received packet upon allocation failure · 75963576

Ido Schimmel authored Oct 24, 2021

When the driver fails to allocate a new Rx buffer, it passes an empty Rx
descriptor (contains zero address and size) to the device and marks it
as invalid by setting the skb pointer in the descriptor's metadata to
NULL.

After processing enough Rx descriptors, the driver will try to process
the invalid descriptor, but will return immediately seeing that the skb
pointer is NULL. Since the driver no longer passes new Rx descriptors to
the device, the Rx queue will eventually become full and the device will
start to drop packets.

Fix this by recycling the received packet if allocation of the new
packet failed. This means that allocation is no longer performed at the
end of the Rx routine, but at the start, before tearing down the DMA
mapping of the received packet.

Remove the comment about the descriptor being zeroed as it is no longer
correct. This is OK because we either use the descriptor as-is (when
recycling) or overwrite its address and size fields with that of the
newly allocated Rx buffer.

The issue was discovered when a process ("perf") consumed too much
memory and put the system under memory pressure. It can be reproduced by
injecting slab allocation failures [1]. After the fix, the Rx queue no
longer comes to a halt.

[1]
 # echo 10 > /sys/kernel/debug/failslab/times
 # echo 1000 > /sys/kernel/debug/failslab/interval
 # echo 100 > /sys/kernel/debug/failslab/probability

 FAULT_INJECTION: forcing a failure.
 name failslab, interval 1000, probability 100, space 0, times 8
 [...]
 Call Trace:
  <IRQ>
  dump_stack_lvl+0x34/0x44
  should_fail.cold+0x32/0x37
  should_failslab+0x5/0x10
  kmem_cache_alloc_node+0x23/0x190
  __alloc_skb+0x1f9/0x280
  __netdev_alloc_skb+0x3a/0x150
  mlxsw_pci_rdq_skb_alloc+0x24/0x90
  mlxsw_pci_cq_tasklet+0x3dc/0x1200
  tasklet_action_common.constprop.0+0x9f/0x100
  __do_softirq+0xb5/0x252
  irq_exit_rcu+0x7a/0xa0
  common_interrupt+0x83/0xa0
  </IRQ>
  asm_common_interrupt+0x1e/0x40
 RIP: 0010:cpuidle_enter_state+0xc8/0x340
 [...]
 mlxsw_spectrum2 0000:06:00.0: Failed to alloc skb for RDQ

Fixes: eda6500a ("mlxsw: Add PCI bus implementation")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/20211024064014.1060919-1-idosch@idosch.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>

75963576

25 Oct, 2021 9 commits

net-sysfs: initialize uid and gid before calling net_ns_get_ownership · f7a1e76d

Xin Long authored Oct 25, 2021

Currently in net_ns_get_ownership() it may not be able to set uid or gid
if make_kuid or make_kgid returns an invalid value, and an uninit-value
issue can be triggered by this.

This patch is to fix it by initializing the uid and gid before calling
net_ns_get_ownership(), as it does in kobject_get_ownership()

Fixes: e6dee9f3 ("net-sysfs: add netdev_change_owner()")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

f7a1e76d

xen/netfront: stop tx queues during live migration · 042b2046

Dongli Zhang authored Oct 22, 2021

The tx queues are not stopped during the live migration. As a result, the
ndo_start_xmit() may access netfront_info->queues which is freed by
talk_to_netback()->xennet_destroy_queues().

This patch is to netif_device_detach() at the beginning of xen-netfront
resuming, and netif_device_attach() at the end of resuming.

     CPU A                                CPU B

 talk_to_netback()
 -> if (info->queues)
        xennet_destroy_queues(info);
    to free netfront_info->queues

                                        xennet_start_xmit()
                                        to access netfront_info->queues

  -> err = xennet_create_queues(info, &num_queues);

The idea is borrowed from virtio-net.

Cc: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

042b2046

net: Prevent infinite while loop in skb_tx_hash() · 0c57eeec

Michael Chan authored Oct 25, 2021

Drivers call netdev_set_num_tc() and then netdev_set_tc_queue()
to set the queue count and offset for each TC. So the queue count
and offset for the TCs may be zero for a short period after dev->num_tc
has been set. If a TX packet is being transmitted at this time in the
code path netdev_pick_tx() -> skb_tx_hash(), skb_tx_hash() may see
nonzero dev->num_tc but zero qcount for the TC. The while loop that
keeps looping while hash >= qcount will not end.

Fix it by checking the TC's qcount to be nonzero before using it.

Fixes: eadec877 ("net: Add support for subordinate traffic classes to netdev_pick_tx")
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

0c57eeec

net: nxp: lpc_eth.c: avoid hang when bringing interface down · ace19b99

Trevor Woerner authored Oct 24, 2021

A hard hang is observed whenever the ethernet interface is brought
down. If the PHY is stopped before the LPC core block is reset,
the SoC will hang. Comparing lpc_eth_close() and lpc_eth_open() I
re-arranged the ordering of the functions calls in lpc_eth_close() to
reset the hardware before stopping the PHY.
Fixes: b7370112 ("lpc32xx: Added ethernet driver")
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ace19b99

Merge branch 'ksettings-locking-fixes' · b4ab21f9

David S. Miller authored Oct 25, 2021

Andrew Lunn says:

====================
ksettings_{get|set} lock fixes

Walter Stoll <Walter.Stoll@duagon.com> reported a race condition
between "ethtool -s eth0 speed 100 duplex full autoneg off" and phylib
reading the current status from the PHY. Both ksetting_get and
ksetting_set fail the take the phydev mutex, and as a result, there is
a small window of time where the phydev members are not self
consistent.

Patch 1 fixes phy_ethtool_ksettings_get by adding the needed lock.
Patches 2 and 3 move code around and perform to refactoring, to allow
patch 4 to fix phy_ethtool_ksettings_set by added the lock.

Thanks go to Walter for the detailed origional report, suggested fix,
and testing of the proposed patches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

b4ab21f9

phy: phy_ethtool_ksettings_set: Lock the PHY while changing settings · af1a02aa

Andrew Lunn authored Oct 24, 2021

There is a race condition where the PHY state machine can change
members of the phydev structure at the same time userspace requests a
change via ethtool. To prevent this, have phy_ethtool_ksettings_set
take the PHY lock.

Fixes: 2d55173e ("phy: add generic function to support ksetting support")
Reported-by: Walter Stoll <Walter.Stoll@duagon.com>
Suggested-by: Walter Stoll <Walter.Stoll@duagon.com>
Tested-by: Walter Stoll <Walter.Stoll@duagon.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

af1a02aa

phy: phy_start_aneg: Add an unlocked version · 707293a5

Andrew Lunn authored Oct 24, 2021

Split phy_start_aneg into a wrapper which takes the PHY lock, and a
helper doing the real work. This will be needed when
phy_ethtook_ksettings_set takes the lock.

Fixes: 2d55173e ("phy: add generic function to support ksetting support")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

707293a5

phy: phy_ethtool_ksettings_set: Move after phy_start_aneg · 64cd92d5

Andrew Lunn authored Oct 24, 2021

This allows it to make use of a helper which assume the PHY is already
locked.

Fixes: 2d55173e ("phy: add generic function to support ksetting support")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

64cd92d5

phy: phy_ethtool_ksettings_get: Lock the phy for consistency · c10a485c

Andrew Lunn authored Oct 24, 2021

The PHY structure should be locked while copying information out if
it, otherwise there is no guarantee of self consistency. Without the
lock the PHY state machine could be updating the structure.

Fixes: 2d55173e ("phy: add generic function to support ksetting support")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

c10a485c

24 Oct, 2021 2 commits

net: ethernet: microchip: lan743x: Fix dma allocation failure by using dma_set_mask_and_coherent · 95a359c9

Yuiko Oshino authored Oct 22, 2021

The dma failure was reported in the raspberry pi github (issue #4117).
https://github.com/raspberrypi/linux/issues/4117
The use of dma_set_mask_and_coherent fixes the issue.
Tested on 32/64-bit raspberry pi CM4 and 64-bit ubuntu x86 PC with EVB-LAN7430.

Fixes: 23f0703c ("lan743x: Add main source files for new lan743x driver")
Signed-off-by: Yuiko Oshino <yuiko.oshino@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

95a359c9

net: ethernet: microchip: lan743x: Fix driver crash when lan743x_pm_resume fails · d6423d2e

Yuiko Oshino authored Oct 22, 2021

The driver needs to clean up and return when the initialization fails on resume.

Fixes: 23f0703c ("lan743x: Add main source files for new lan743x driver")
Signed-off-by: Yuiko Oshino <yuiko.oshino@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

d6423d2e

22 Oct, 2021 17 commits

fcnal-test: kill hanging ping/nettest binaries on cleanup · 1f83b835

Florian Westphal authored Oct 21, 2021

On my box I see a bunch of ping/nettest processes hanging
around after fcntal-test.sh is done.

Clean those up before netns deletion.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211021140247.29691-1-fw@strlen.deSigned-off-by: Jakub Kicinski <kuba@kernel.org>

1f83b835

Merge branch 'sctp-enhancements-for-the-verification-tag' · 32f8807a

Jakub Kicinski authored Oct 22, 2021

Xin Long says:

====================
sctp: enhancements for the verification tag

This patchset is to address CVE-2021-3772:

  A flaw was found in the Linux SCTP stack. A blind attacker may be able to
  kill an existing SCTP association through invalid chunks if the attacker
  knows the IP-addresses and port numbers being used and the attacker can
  send packets with spoofed IP addresses.

This is caused by the missing VTAG verification for the received chunks
and the incorrect vtag for the ABORT used to reply to these invalid
chunks.

This patchset is to go over all processing functions for the received
chunks and do:

1. Make sure sctp_vtag_verify() is called firstly to verify the vtag from
   the received chunk and discard this chunk if it fails. With some
   exceptions:

   a. sctp_sf_do_5_1B_init()/5_2_2_dupinit()/9_2_reshutack(), processing
      INIT chunk, as sctphdr vtag is always 0 in INIT chunk.

   b. sctp_sf_do_5_2_4_dupcook(), processing dupicate COOKIE_ECHO chunk,
      as the vtag verification will be done by sctp_tietags_compare() and
      then it takes right actions according to the return.

   c. sctp_sf_shut_8_4_5(), processing SHUTDOWN_ACK chunk for cookie_wait
      and cookie_echoed state, as RFC demand sending a SHUTDOWN_COMPLETE
      even if the vtag verification failed.

   d. sctp_sf_ootb(), called in many types of chunks for closed state or
      no asoc, as the same reason to c.

2. Always use the vtag from the received INIT chunk to make the response
   ABORT in sctp_ootb_pkt_new().

3. Fix the order for some checks and add some missing checks for the
   received chunk.

This patch series has been tested with SCTP TAHI testing to make sure no
regression caused on protocol conformance.
====================

Link: https://lore.kernel.org/r/cover.1634730082.git.lucien.xin@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

32f8807a

sctp: add vtag check in sctp_sf_ootb · 9d02831e