Commit Graph

116 Commits

Author SHA1 Message Date
Zhengchao Shao
762c8dc7f2 net: dst: remove unnecessary input parameter in dst_alloc and dst_init
Since commit 1202cdd66531("Remove DECnet support from kernel") has been
merged, all callers pass in the initial_ref value of 1 when they call
dst_alloc(). Therefore, remove initial_ref when the dst_alloc() is
declared and replace initial_ref with 1 in dst_alloc().
Also when all callers call dst_init(), the value of initial_ref is 1.
Therefore, remove the input parameter initial_ref of the dst_init() and
replace initial_ref with the value 1 in dst_init.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Link: https://lore.kernel.org/r/20230911125045.346390-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-12 11:42:25 +02:00
Zhengchao Shao
43c2817225 net: remove unnecessary input parameter 'how' in ifdown function
When the ifdown function in the dst_ops structure is referenced, the input
parameter 'how' is always true. In the current implementation of the
ifdown interface, ip6_dst_ifdown does not use the input parameter 'how',
xfrm6_dst_ifdown and xfrm4_dst_ifdown functions use the input parameter
'unregister'. But false judgment on 'unregister' in xfrm6_dst_ifdown and
xfrm4_dst_ifdown is false, so remove the input parameter 'how' in ifdown
function.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230821084104.3812233-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-08-22 13:19:02 +02:00
Maxime Bizon
418a73074d net: dst: fix missing initialization of rt_uncached
xfrm_alloc_dst() followed by xfrm4_dst_destroy(), without a
xfrm4_fill_dst() call in between, causes the following BUG:

 BUG: spinlock bad magic on CPU#0, fbxhostapd/732
  lock: 0x890b7668, .magic: 890b7668, .owner: <none>/-1, .owner_cpu: 0
 CPU: 0 PID: 732 Comm: fbxhostapd Not tainted 6.3.0-rc6-next-20230414-00613-ge8de66369925-dirty #9
 Hardware name: Marvell Kirkwood (Flattened Device Tree)
  unwind_backtrace from show_stack+0x10/0x14
  show_stack from dump_stack_lvl+0x28/0x30
  dump_stack_lvl from do_raw_spin_lock+0x20/0x80
  do_raw_spin_lock from rt_del_uncached_list+0x30/0x64
  rt_del_uncached_list from xfrm4_dst_destroy+0x3c/0xbc
  xfrm4_dst_destroy from dst_destroy+0x5c/0xb0
  dst_destroy from rcu_process_callbacks+0xc4/0xec
  rcu_process_callbacks from __do_softirq+0xb4/0x22c
  __do_softirq from call_with_stack+0x1c/0x24
  call_with_stack from do_softirq+0x60/0x6c
  do_softirq from __local_bh_enable_ip+0xa0/0xcc

Patch "net: dst: Prevent false sharing vs. dst_entry:: __refcnt" moved
rt_uncached and rt_uncached_list fields from rtable struct to dst
struct, so they are more zeroed by memset_after(xdst, 0, u.dst) in
xfrm_alloc_dst().

Note that rt_uncached (list_head) was never properly initialized at
alloc time, but xfrm[46]_dst_destroy() is written in such a way that
it was not an issue thanks to the memset:

	if (xdst->u.rt.dst.rt_uncached_list)
		rt_del_uncached_list(&xdst->u.rt);

The route code does it the other way around: rt_uncached_list is
assumed to be valid IIF rt_uncached list_head is not empty:

void rt_del_uncached_list(struct rtable *rt)
{
        if (!list_empty(&rt->dst.rt_uncached)) {
                struct uncached_list *ul = rt->dst.rt_uncached_list;

                spin_lock_bh(&ul->lock);
                list_del_init(&rt->dst.rt_uncached);
                spin_unlock_bh(&ul->lock);
        }
}

This patch adds mandatory rt_uncached list_head initialization in
generic dst_init(), and adapt xfrm[46]_dst_destroy logic to match the
rest of the code.

Fixes: d288a162dd ("net: dst: Prevent false sharing vs. dst_entry:: __refcnt")
Reported-by: kernel test robot <oliver.sang@intel.com>
Link: https://lore.kernel.org/oe-lkp/202304162125.18b7bcdd-oliver.sang@intel.com
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
CC: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Link: https://lore.kernel.org/r/20230420182508.2417582-1-mbizon@freebox.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21 20:26:56 -07:00
Thomas Gleixner
bc9d3a9f2a net: dst: Switch to rcuref_t reference counting
Under high contention dst_entry::__refcnt becomes a significant bottleneck.

atomic_inc_not_zero() is implemented with a cmpxchg() loop, which goes into
high retry rates on contention.

Switch the reference count to rcuref_t which results in a significant
performance gain. Rename the reference count member to __rcuref to reflect
the change.

The gain depends on the micro-architecture and the number of concurrent
operations and has been measured in the range of +25% to +130% with a
localhost memtier/memcached benchmark which amplifies the problem
massively.

Running the memtier/memcached benchmark over a real (1Gb) network
connection the conversion on top of the false sharing fix for struct
dst_entry::__refcnt results in a total gain in the 2%-5% range over the
upstream baseline.

Reported-by: Wangyang Guo <wangyang.guo@intel.com>
Reported-by: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230307125538.989175656@linutronix.de
Link: https://lore.kernel.org/r/20230323102800.215027837@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-28 18:52:28 -07:00
Jon Maxwell
af6d10345c ipv6: remove max_size check inline with ipv4
In ip6_dst_gc() replace:

  if (entries > gc_thresh)

With:

  if (entries > ops->gc_thresh)

Sending Ipv6 packets in a loop via a raw socket triggers an issue where a
route is cloned by ip6_rt_cache_alloc() for each packet sent. This quickly
consumes the Ipv6 max_size threshold which defaults to 4096 resulting in
these warnings:

[1]   99.187805] dst_alloc: 7728 callbacks suppressed
[2] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.
.
.
[300] Route cache is full: consider increasing sysctl net.ipv6.route.max_size.

When this happens the packet is dropped and sendto() gets a network is
unreachable error:

remaining pkt 200557 errno 101
remaining pkt 196462 errno 101
.
.
remaining pkt 126821 errno 101

Implement David Aherns suggestion to remove max_size check seeing that Ipv6
has a GC to manage memory usage. Ipv4 already does not check max_size.

Here are some memory comparisons for Ipv4 vs Ipv6 with the patch:

Test by running 5 instances of a program that sends UDP packets to a raw
socket 5000000 times. Compare Ipv4 and Ipv6 performance with a similar
program.

Ipv4:

Before test:

MemFree:        29427108 kB
Slab:             237612 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        2881   3990    192   42    2 : tunables    0    0    0

During test:

MemFree:        29417608 kB
Slab:             247712 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache       44394  44394    192   42    2 : tunables    0    0    0

After test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Ipv6 with patch:

Errno 101 errors are not observed anymore with the patch.

Before test:

MemFree:        29422308 kB
Slab:             238104 kB

ip6_dst_cache       1912   2528    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

During Test:

MemFree:        29431516 kB
Slab:             240940 kB

ip6_dst_cache      11980  12064    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

After Test:

MemFree:        29441816 kB
Slab:             238132 kB

ip6_dst_cache       1902   2432    256   32    2 : tunables    0    0    0
xfrm_dst_cache         0      0    320   25    2 : tunables    0    0    0
ip_dst_cache        3048   4116    192   42    2 : tunables    0    0    0

Tested-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230112012532.311021-1-jmaxwell37@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-13 20:59:14 -08:00
Linus Torvalds
7e68dd7d07 Networking changes for 6.2.
Core
 ----
  - Allow live renaming when an interface is up
 
  - Add retpoline wrappers for tc, improving considerably the
    performances of complex queue discipline configurations.
 
  - Add inet drop monitor support.
 
  - A few GRO performance improvements.
 
  - Add infrastructure for atomic dev stats, addressing long standing
    data races.
 
  - De-duplicate common code between OVS and conntrack offloading
    infrastructure.
 
  - A bunch of UBSAN_BOUNDS/FORTIFY_SOURCE improvements.
 
  - Netfilter: introduce packet parser for tunneled packets
 
  - Replace IPVS timer-based estimators with kthreads to scale up
    the workload with the number of available CPUs.
 
  - Add the helper support for connection-tracking OVS offload.
 
 BPF
 ---
  - Support for user defined BPF objects: the use case is to allocate
    own objects, build own object hierarchies and use the building
    blocks to build own data structures flexibly, for example, linked
    lists in BPF.
 
  - Make cgroup local storage available to non-cgroup attached BPF
    programs.
 
  - Avoid unnecessary deadlock detection and failures wrt BPF task
    storage helpers.
 
  - A relevant bunch of BPF verifier fixes and improvements.
 
  - Veristat tool improvements to support custom filtering, sorting,
    and replay of results.
 
  - Add LLVM disassembler as default library for dumping JITed code.
 
  - Lots of new BPF documentation for various BPF maps.
 
  - Add bpf_rcu_read_{,un}lock() support for sleepable programs.
 
  - Add RCU grace period chaining to BPF to wait for the completion
    of access from both sleepable and non-sleepable BPF programs.
 
  - Add support storing struct task_struct objects as kptrs in maps.
 
  - Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer
    values.
 
  - Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions.
 
 Protocols
 ---------
  - TCP: implement Protective Load Balancing across switch links.
 
  - TCP: allow dynamically disabling TCP-MD5 static key, reverting
    back to fast[er]-path.
 
  - UDP: Introduce optional per-netns hash lookup table.
 
  - IPv6: simplify and cleanup sockets disposal.
 
  - Netlink: support different type policies for each generic
    netlink operation.
 
  - MPTCP: add MSG_FASTOPEN and FastOpen listener side support.
 
  - MPTCP: add netlink notification support for listener sockets
    events.
 
  - SCTP: add VRF support, allowing sctp sockets binding to VRF
    devices.
 
  - Add bridging MAC Authentication Bypass (MAB) support.
 
  - Extensions for Ethernet VPN bridging implementation to better
    support multicast scenarios.
 
  - More work for Wi-Fi 7 support, comprising conversion of all
    the existing drivers to internal TX queue usage.
 
  - IPSec: introduce a new offload type (packet offload) allowing
    complete header processing and crypto offloading.
 
  - IPSec: extended ack support for more descriptive XFRM error
    reporting.
 
  - RXRPC: increase SACK table size and move processing into a
    per-local endpoint kernel thread, reducing considerably the
    required locking.
 
  - IEEE 802154: synchronous send frame and extended filtering
    support, initial support for scanning available 15.4 networks.
 
  - Tun: bump the link speed from 10Mbps to 10Gbps.
 
  - Tun/VirtioNet: implement UDP segmentation offload support.
 
 Driver API
 ----------
 
  - PHY/SFP: improve power level switching between standard
    level 1 and the higher power levels.
 
  - New API for netdev <-> devlink_port linkage.
 
  - PTP: convert existing drivers to new frequency adjustment
    implementation.
 
  - DSA: add support for rx offloading.
 
  - Autoload DSA tagging driver when dynamically changing protocol.
 
  - Add new PCP and APPTRUST attributes to Data Center Bridging.
 
  - Add configuration support for 800Gbps link speed.
 
  - Add devlink port function attribute to enable/disable RoCE and
    migratable.
 
  - Extend devlink-rate to support strict prioriry and weighted fair
    queuing.
 
  - Add devlink support to directly reading from region memory.
 
  - New device tree helper to fetch MAC address from nvmem.
 
  - New big TCP helper to simplify temporary header stripping.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Marvel Octeon CNF95N and CN10KB Ethernet Switches.
    - Marvel Prestera AC5X Ethernet Switch.
    - WangXun 10 Gigabit NIC.
    - Motorcomm yt8521 Gigabit Ethernet.
    - Microchip ksz9563 Gigabit Ethernet Switch.
    - Microsoft Azure Network Adapter.
    - Linux Automation 10Base-T1L adapter.
 
  - PHY:
    - Aquantia AQR112 and AQR412.
    - Motorcomm YT8531S.
 
  - PTP:
    - Orolia ART-CARD.
 
  - WiFi:
    - MediaTek Wi-Fi 7 (802.11be) devices.
    - RealTek rtw8821cu, rtw8822bu, rtw8822cu and rtw8723du USB
      devices.
 
  - Bluetooth:
    - Broadcom BCM4377/4378/4387 Bluetooth chipsets.
    - Realtek RTL8852BE and RTL8723DS.
    - Cypress.CYW4373A0 WiFi + Bluetooth combo device.
 
 Drivers
 -------
  - CAN:
    - gs_usb: bus error reporting support.
    - kvaser_usb: listen only and bus error reporting support.
 
  - Ethernet NICs:
    - Intel (100G):
      - extend action skbedit to RX queue mapping.
      - implement devlink-rate support.
      - support direct read from memory.
    - nVidia/Mellanox (mlx5):
      - SW steering improvements, increasing rules update rate.
      - Support for enhanced events compression.
      - extend H/W offload packet manipulation capabilities.
      - implement IPSec packet offload mode.
    - nVidia/Mellanox (mlx4):
      - better big TCP support.
    - Netronome Ethernet NICs (nfp):
      - IPsec offload support.
      - add support for multicast filter.
    - Broadcom:
      - RSS and PTP support improvements.
    - AMD/SolarFlare:
      - netlink extened ack improvements.
      - add basic flower matches to offload, and related stats.
    - Virtual NICs:
      - ibmvnic: introduce affinity hint support.
    - small / embedded:
      - FreeScale fec: add initial XDP support.
      - Marvel mv643xx_eth: support MII/GMII/RGMII modes for Kirkwood.
      - TI am65-cpsw: add suspend/resume support.
      - Mediatek MT7986: add RX wireless wthernet dispatch support.
      - Realtek 8169: enable GRO software interrupt coalescing per
        default.
 
  - Ethernet high-speed switches:
    - Microchip (sparx5):
      - add support for Sparx5 TC/flower H/W offload via VCAP.
    - Mellanox mlxsw:
      - add 802.1X and MAC Authentication Bypass offload support.
      - add ip6gre support.
 
  - Embedded Ethernet switches:
    - Mediatek (mtk_eth_soc):
      - improve PCS implementation, add DSA untag support.
      - enable flow offload support.
    - Renesas:
      - add rswitch R-Car Gen4 gPTP support.
    - Microchip (lan966x):
      - add full XDP support.
      - add TC H/W offload via VCAP.
      - enable PTP on bridge interfaces.
    - Microchip (ksz8):
      - add MTU support for KSZ8 series.
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - support configuring channel dwell time during scan.
 
  - MediaTek WiFi (mt76):
    - enable Wireless Ethernet Dispatch (WED) offload support.
    - add ack signal support.
    - enable coredump support.
    - remain_on_channel support.
 
  - Intel WiFi (iwlwifi):
    - enable Wi-Fi 7 Extremely High Throughput (EHT) PHY capabilities.
    - 320 MHz channels support.
 
  - RealTek WiFi (rtw89):
    - new dynamic header firmware format support.
    - wake-over-WLAN support.
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Paolo Abeni:
 "Core:

   - Allow live renaming when an interface is up

   - Add retpoline wrappers for tc, improving considerably the
     performances of complex queue discipline configurations

   - Add inet drop monitor support

   - A few GRO performance improvements

   - Add infrastructure for atomic dev stats, addressing long standing
     data races

   - De-duplicate common code between OVS and conntrack offloading
     infrastructure

   - A bunch of UBSAN_BOUNDS/FORTIFY_SOURCE improvements

   - Netfilter: introduce packet parser for tunneled packets

   - Replace IPVS timer-based estimators with kthreads to scale up the
     workload with the number of available CPUs

   - Add the helper support for connection-tracking OVS offload

  BPF:

   - Support for user defined BPF objects: the use case is to allocate
     own objects, build own object hierarchies and use the building
     blocks to build own data structures flexibly, for example, linked
     lists in BPF

   - Make cgroup local storage available to non-cgroup attached BPF
     programs

   - Avoid unnecessary deadlock detection and failures wrt BPF task
     storage helpers

   - A relevant bunch of BPF verifier fixes and improvements

   - Veristat tool improvements to support custom filtering, sorting,
     and replay of results

   - Add LLVM disassembler as default library for dumping JITed code

   - Lots of new BPF documentation for various BPF maps

   - Add bpf_rcu_read_{,un}lock() support for sleepable programs

   - Add RCU grace period chaining to BPF to wait for the completion of
     access from both sleepable and non-sleepable BPF programs

   - Add support storing struct task_struct objects as kptrs in maps

   - Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer
     values

   - Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions

  Protocols:

   - TCP: implement Protective Load Balancing across switch links

   - TCP: allow dynamically disabling TCP-MD5 static key, reverting back
     to fast[er]-path

   - UDP: Introduce optional per-netns hash lookup table

   - IPv6: simplify and cleanup sockets disposal

   - Netlink: support different type policies for each generic netlink
     operation

   - MPTCP: add MSG_FASTOPEN and FastOpen listener side support

   - MPTCP: add netlink notification support for listener sockets events

   - SCTP: add VRF support, allowing sctp sockets binding to VRF devices

   - Add bridging MAC Authentication Bypass (MAB) support

   - Extensions for Ethernet VPN bridging implementation to better
     support multicast scenarios

   - More work for Wi-Fi 7 support, comprising conversion of all the
     existing drivers to internal TX queue usage

   - IPSec: introduce a new offload type (packet offload) allowing
     complete header processing and crypto offloading

   - IPSec: extended ack support for more descriptive XFRM error
     reporting

   - RXRPC: increase SACK table size and move processing into a
     per-local endpoint kernel thread, reducing considerably the
     required locking

   - IEEE 802154: synchronous send frame and extended filtering support,
     initial support for scanning available 15.4 networks

   - Tun: bump the link speed from 10Mbps to 10Gbps

   - Tun/VirtioNet: implement UDP segmentation offload support

  Driver API:

   - PHY/SFP: improve power level switching between standard level 1 and
     the higher power levels

   - New API for netdev <-> devlink_port linkage

   - PTP: convert existing drivers to new frequency adjustment
     implementation

   - DSA: add support for rx offloading

   - Autoload DSA tagging driver when dynamically changing protocol

   - Add new PCP and APPTRUST attributes to Data Center Bridging

   - Add configuration support for 800Gbps link speed

   - Add devlink port function attribute to enable/disable RoCE and
     migratable

   - Extend devlink-rate to support strict prioriry and weighted fair
     queuing

   - Add devlink support to directly reading from region memory

   - New device tree helper to fetch MAC address from nvmem

   - New big TCP helper to simplify temporary header stripping

  New hardware / drivers:

   - Ethernet:
      - Marvel Octeon CNF95N and CN10KB Ethernet Switches
      - Marvel Prestera AC5X Ethernet Switch
      - WangXun 10 Gigabit NIC
      - Motorcomm yt8521 Gigabit Ethernet
      - Microchip ksz9563 Gigabit Ethernet Switch
      - Microsoft Azure Network Adapter
      - Linux Automation 10Base-T1L adapter

   - PHY:
      - Aquantia AQR112 and AQR412
      - Motorcomm YT8531S

   - PTP:
      - Orolia ART-CARD

   - WiFi:
      - MediaTek Wi-Fi 7 (802.11be) devices
      - RealTek rtw8821cu, rtw8822bu, rtw8822cu and rtw8723du USB
        devices

   - Bluetooth:
      - Broadcom BCM4377/4378/4387 Bluetooth chipsets
      - Realtek RTL8852BE and RTL8723DS
      - Cypress.CYW4373A0 WiFi + Bluetooth combo device

  Drivers:

   - CAN:
      - gs_usb: bus error reporting support
      - kvaser_usb: listen only and bus error reporting support

   - Ethernet NICs:
      - Intel (100G):
         - extend action skbedit to RX queue mapping
         - implement devlink-rate support
         - support direct read from memory
      - nVidia/Mellanox (mlx5):
         - SW steering improvements, increasing rules update rate
         - Support for enhanced events compression
         - extend H/W offload packet manipulation capabilities
         - implement IPSec packet offload mode
      - nVidia/Mellanox (mlx4):
         - better big TCP support
      - Netronome Ethernet NICs (nfp):
         - IPsec offload support
         - add support for multicast filter
      - Broadcom:
         - RSS and PTP support improvements
      - AMD/SolarFlare:
         - netlink extened ack improvements
         - add basic flower matches to offload, and related stats
      - Virtual NICs:
         - ibmvnic: introduce affinity hint support
      - small / embedded:
         - FreeScale fec: add initial XDP support
         - Marvel mv643xx_eth: support MII/GMII/RGMII modes for Kirkwood
         - TI am65-cpsw: add suspend/resume support
         - Mediatek MT7986: add RX wireless wthernet dispatch support
         - Realtek 8169: enable GRO software interrupt coalescing per
           default

   - Ethernet high-speed switches:
      - Microchip (sparx5):
         - add support for Sparx5 TC/flower H/W offload via VCAP
      - Mellanox mlxsw:
         - add 802.1X and MAC Authentication Bypass offload support
         - add ip6gre support

   - Embedded Ethernet switches:
      - Mediatek (mtk_eth_soc):
         - improve PCS implementation, add DSA untag support
         - enable flow offload support
      - Renesas:
         - add rswitch R-Car Gen4 gPTP support
      - Microchip (lan966x):
         - add full XDP support
         - add TC H/W offload via VCAP
         - enable PTP on bridge interfaces
      - Microchip (ksz8):
         - add MTU support for KSZ8 series

   - Qualcomm 802.11ax WiFi (ath11k):
      - support configuring channel dwell time during scan

   - MediaTek WiFi (mt76):
      - enable Wireless Ethernet Dispatch (WED) offload support
      - add ack signal support
      - enable coredump support
      - remain_on_channel support

   - Intel WiFi (iwlwifi):
      - enable Wi-Fi 7 Extremely High Throughput (EHT) PHY capabilities
      - 320 MHz channels support

   - RealTek WiFi (rtw89):
      - new dynamic header firmware format support
      - wake-over-WLAN support"

* tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2002 commits)
  ipvs: fix type warning in do_div() on 32 bit
  net: lan966x: Remove a useless test in lan966x_ptp_add_trap()
  net: ipa: add IPA v4.7 support
  dt-bindings: net: qcom,ipa: Add SM6350 compatible
  bnxt: Use generic HBH removal helper in tx path
  IPv6/GRO: generic helper to remove temporary HBH/jumbo header in driver
  selftests: forwarding: Add bridge MDB test
  selftests: forwarding: Rename bridge_mdb test
  bridge: mcast: Support replacement of MDB port group entries
  bridge: mcast: Allow user space to specify MDB entry routing protocol
  bridge: mcast: Allow user space to add (*, G) with a source list and filter mode
  bridge: mcast: Add support for (*, G) with a source list and filter mode
  bridge: mcast: Avoid arming group timer when (S, G) corresponds to a source
  bridge: mcast: Add a flag for user installed source entries
  bridge: mcast: Expose __br_multicast_del_group_src()
  bridge: mcast: Expose br_multicast_new_group_src()
  bridge: mcast: Add a centralized error path
  bridge: mcast: Place netlink policy before validation functions
  bridge: mcast: Split (*, G) and (S, G) addition into different functions
  bridge: mcast: Do not derive entry type from its filter mode
  ...
2022-12-13 15:47:48 -08:00
Eyal Birger
94151f5aa9 xfrm: interface: Add unstable helpers for setting/getting XFRM metadata from TC-BPF
This change adds xfrm metadata helpers using the unstable kfunc call
interface for the TC-BPF hooks. This allows steering traffic towards
different IPsec connections based on logic implemented in bpf programs.

This object is built based on the availability of BTF debug info.

When setting the xfrm metadata, percpu metadata dsts are used in order
to avoid allocating a metadata dst per packet.

In order to guarantee safe module unload, the percpu dsts are allocated
on first use and never freed. The percpu pointer is stored in
net/core/filter.c so that it can be reused on module reload.

The metadata percpu dsts take ownership of the original skb dsts so
that they may be used as part of the xfrm transmission logic - e.g.
for MTU calculations.

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Link: https://lore.kernel.org/r/20221203084659.1837829-3-eyal.birger@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-12-05 21:58:27 -08:00
Joel Fernandes (Google)
483c26ff63 net: Use call_rcu_hurry() for dst_release()
In a networking test on ChromeOS, kernels built with the new
CONFIG_RCU_LAZY=y Kconfig option fail a networking test in the teardown
phase.

This failure may be reproduced as follows: ip netns del <name>

The CONFIG_RCU_LAZY=y Kconfig option was introduced by earlier commits
in this series for the benefit of certain battery-powered systems.
This Kconfig option causes call_rcu() to delay its callbacks in order
to batch them.  This means that a given RCU grace period covers more
callbacks, thus reducing the number of grace periods, in turn reducing
the amount of energy consumed, which increases battery lifetime which
can be a very good thing.  This is not a subtle effect: In some important
use cases, the battery lifetime is increased by more than 10%.

This CONFIG_RCU_LAZY=y option is available only for CPUs that offload
callbacks, for example, CPUs mentioned in the rcu_nocbs kernel boot
parameter passed to kernels built with CONFIG_RCU_NOCB_CPU=y.

Delaying callbacks is normally not a problem because most callbacks do
nothing but free memory.  If the system is short on memory, a shrinker
will kick all currently queued lazy callbacks out of their laziness,
thus freeing their memory in short order.  Similarly, the rcu_barrier()
function, which blocks until all currently queued callbacks are invoked,
will also kick lazy callbacks, thus enabling rcu_barrier() to complete
in a timely manner.

However, there are some cases where laziness is not a good option.
For example, synchronize_rcu() invokes call_rcu(), and blocks until
the newly queued callback is invoked.  It would not be a good for
synchronize_rcu() to block for ten seconds, even on an idle system.
Therefore, synchronize_rcu() invokes call_rcu_hurry() instead of
call_rcu().  The arrival of a non-lazy call_rcu_hurry() callback on a
given CPU kicks any lazy callbacks that might be already queued on that
CPU.  After all, if there is going to be a grace period, all callbacks
might as well get full benefit from it.

Yes, this could be done the other way around by creating a
call_rcu_lazy(), but earlier experience with this approach and
feedback at the 2022 Linux Plumbers Conference shifted the approach
to call_rcu() being lazy with call_rcu_hurry() for the few places
where laziness is inappropriate.

Returning to the test failure, use of ftrace showed that this failure
cause caused by the aadded delays due to this new lazy behavior of
call_rcu() in kernels built with CONFIG_RCU_LAZY=y.

Therefore, make dst_release() use call_rcu_hurry() in order to revert
to the old test-failure-free behavior.

[ paulmck: Apply s/call_rcu_flush/call_rcu_hurry/ feedback from Tejun Heo. ]

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: <netdev@vger.kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2022-11-30 13:17:25 -08:00
Jakub Kicinski
d62607c3fe net: rename reference+tracking helpers
Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.

Rename:
 dev_hold_track()    -> netdev_hold()
 dev_put_track()     -> netdev_put()
 dev_replace_track() -> netdev_ref_replace()

Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-09 21:52:55 -07:00
Eric Dumazet
9038c32000 net: dst: add net device refcount tracking to dst_entry
We want to track all dev_hold()/dev_put() to ease leak hunting.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-06 16:05:10 -08:00
Yajun Deng
1160dfa178 net: Remove redundant if statements
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-05 13:27:50 +01:00
Daniel Borkmann
a188bb5638 net, bpf: Fix ip6ip6 crash with collect_md populated skbs
I ran into a crash where setting up a ip6ip6 tunnel device which was /not/
set to collect_md mode was receiving collect_md populated skbs for xmit.

The BPF prog was populating the skb via bpf_skb_set_tunnel_key() which is
assigning special metadata dst entry and then redirecting the skb to the
device, taking ip6_tnl_start_xmit() -> ipxip6_tnl_xmit() -> ip6_tnl_xmit()
and in the latter it performs a neigh lookup based on skb_dst(skb) where
we trigger a NULL pointer dereference on dst->ops->neigh_lookup() since
the md_dst_ops do not populate neigh_lookup callback with a fake handler.

Transform the md_dst_ops into generic dst_blackhole_ops that can also be
reused elsewhere when needed, and use them for the metadata dst entries as
callback ops.

Also, remove the dst_md_discard{,_out}() ops and rely on dst_discard{,_out}()
from dst_init() which free the skb the same way modulo the splat. Given we
will be able to recover just fine from there, avoid any potential splats
iff this gets ever triggered in future (or worse, panic on warns when set).

Fixes: f38a9eb1f7 ("dst: Metadata destinations")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10 12:24:18 -08:00
Daniel Borkmann
c4c877b273 net: Consolidate common blackhole dst ops
Move generic blackhole dst ops to the core and use them from both
ipv4_dst_blackhole_ops and ip6_dst_blackhole_ops where possible. No
functional change otherwise. We need these also in other locations
and having to define them over and over again is not great.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10 12:24:18 -08:00
Miaohe Lin
1be107de2e net: Correct the comment of dst_dev_put()
Since commit 8d7017fd62 ("blackhole_netdev: use blackhole_netdev to
invalidate dst entries"), we use blackhole_netdev to invalidate dst entries
instead of loopback device anymore.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10 13:28:57 -07:00
Eric Dumazet
cf86a086a1 net/dst: use a smaller percpu_counter batch for dst entries accounting
percpu_counter_add() uses a default batch size which is quite big
on platforms with 256 cpus. (2*256 -> 512)

This means dst_entries_get_fast() can be off by +/- 2*(nr_cpus^2)
(131072 on servers with 256 cpus)

Reduce the batch size to something more reasonable, and
add logic to ip6_dst_gc() to call dst_entries_get_slow()
before calling the _very_ expensive fib6_run_gc() function.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-05-08 21:33:33 -07:00
Jason A. Donenfeld
adecda5bee net: print proper warning on dst underflow
Proper warnings with stack traces make it much easier to figure out
what's doing the double free and create more meaningful bug reports from
users.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-26 09:05:56 +02:00
Mahesh Bandewar
8d7017fd62 blackhole_netdev: use blackhole_netdev to invalidate dst entries
Use blackhole_netdev instead of 'lo' device with lower MTU when marking
dst "dead".

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Tested-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-01 19:34:46 -07:00
Thomas Gleixner
457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Julian Wiedmann
02afc7ad45 net: dst: remove gc leftovers
Get rid of some obsolete gc-related documentation and macros that were
missed in commit 5b7c9a8ff8 ("net: remove dst gc related code").

CC: Wei Wang <weiwan@google.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-21 13:39:25 -07:00
Peter Oskolkov
22c2ad616b net: add a route cache full diagnostic message
In some testing scenarios, dst/route cache can fill up so quickly
that even an explicit GC call occasionally fails to clean it up. This leads
to sporadically failing calls to dst_alloc and "network unreachable" errors
to the user, which is confusing.

This patch adds a diagnostic message to make the cause of the failure
easier to determine.

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:37:25 -08:00
Pablo Neira Ayuso
af308b94a2 netfilter: nf_tables: add tunnel support
This patch implements the tunnel object type that can be used to
configure tunnels via metadata template through the existing lightweight
API from the ingress path.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-08-03 21:12:12 +02:00
David Ahern
d4ead6b34b net/ipv6: move metrics from dst to rt6_info
Similar to IPv4, add fib metrics to the fib struct, which at the moment
is rt6_info. Will be moved to fib6_info in a later patch. Copy metrics
into dst by reference using refcount.

To make the transition:
- add dst_metrics to rt6_info. Default to dst_default_metrics if no
  metrics are passed during route add. No need for a separate pmtu
  entry; it can reference the MTU slot in fib6_metrics

- ip6_convert_metrics allocates memory in the FIB entry and uses
  ip_metrics_convert to copy from netlink attribute to metrics entry

- the convert metrics call is done in ip6_route_info_create simplifying
  the route add path
  + fib6_commit_metrics and fib6_copy_metrics and the temporary
    mx6_config are no longer needed

- add fib6_metric_set helper to change the value of a metric in the
  fib entry since dst_metric_set can no longer be used

- cow_metrics for IPv6 can drop to dst_cow_metrics_generic

- rt6_dst_from_metrics_check is no longer needed

- rt6_fill_node needs the FIB entry and dst as separate arguments to
  keep compatibility with existing output. Current dst address is
  renamed to dest.
  (to be consistent with IPv4 rt6_fill_node really should be split
  into 2 functions similar to fib_dump_info and rt_fill_info)

- rt6_fill_node no longer needs the temporary metrics variable

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 23:41:16 -04:00
David Miller
7149f813d1 net: Remove dst->next
There are no more users.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:27 -05:00
David Miller
0f6c480f23 xfrm: Move dst->path into struct xfrm_dst
The first member of an IPSEC route bundle chain sets it's dst->path to
the underlying ipv4/ipv6 route that carries the bundle.

Stated another way, if one were to follow the xfrm_dst->child chain of
the bundle, the final non-NULL pointer would be the path and point to
either an ipv4 or an ipv6 route.

This is largely used to make sure that PMTU events propagate down to
the correct ipv4 or ipv6 route.

When we don't have the top of an IPSEC bundle 'dst->path == dst'.

Move it down into xfrm_dst and key off of dst->xfrm.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:26 -05:00
David Miller
3a2232e92e ipv6: Move dst->from into struct rt6_info.
The dst->from value is only used by ipv6 routes to track where
a route "came from".

Any time we clone or copy a core ipv6 route in the ipv6 routing
tables, we have the copy/clone's ->from point to the base route.

This is used to handle route expiration properly.

Only ipv6 uses this mechanism, and only ipv6 code references
it.  So it is safe to move it into rt6_info.

Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
2017-11-30 09:54:26 -05:00
David Miller
b6ca8bd5a9 xfrm: Move child route linkage into xfrm_dst.
XFRM bundle child chains look like this:

	xdst1 --> xdst2 --> xdst3 --> path_dst

All of xdstN are xfrm_dst objects and xdst->u.dst.xfrm is non-NULL.
The final child pointer in the chain, here called 'path_dst', is some
other kind of route such as an ipv4 or ipv6 one.

The xfrm output path pops routes, one at a time, via the child
pointer, until we hit one which has a dst->xfrm pointer which
is NULL.

We can easily preserve the above mechanisms with child sitting
only in the xfrm_dst structure.  All children in the chain
before we break out of the xfrm_output() loop have dst->xfrm
non-NULL and are therefore xfrm_dst objects.

Since we break out of the loop when we find dst->xfrm NULL, we
will not try to dereference 'dst' as if it were an xfrm_dst.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-30 09:54:26 -05:00
David Miller
b92cf4aab8 net: Create and use new helper xfrm_dst_child().
Only IPSEC routes have a non-NULL dst->child pointer.  And IPSEC
routes are identified by a non-NULL dst->xfrm pointer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-30 09:54:25 -05:00
Jakub Kicinski
833e0e2f24 net: dst: move cpu inside ifdef to avoid compilation warning
If CONFIG_DST_CACHE is not selected cpu variable
will be unused and we will see a compilation warning.
Move it under the ifdef.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: d66f2b91f9 ("bpf: don't rely on the verifier lock for metadata_dst allocation")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10 15:55:58 -07:00
Jakub Kicinski
d66f2b91f9 bpf: don't rely on the verifier lock for metadata_dst allocation
bpf_skb_set_tunnel_*() functions require allocation of per-cpu
metadata_dst.  The allocation happens upon verification of the
first program using those helpers.  In preparation for removing
the verifier lock, use cmpxchg() to make sure we only allocate
the metadata_dsts once.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10 12:30:16 -07:00
David Lamparter
e65a4955b0 net: check type when freeing metadata dst
Commit 3fcece12bc ("net: store port/representator id in metadata_dst")
added a new type field to metadata_dst, but metadata_dst_free() wasn't
updated to check it before freeing the METADATA_IP_TUNNEL specific dst
cache entry.

This is not currently causing problems since it's far enough back in the
struct to be zeroed for the only other type currently in existance
(METADATA_HW_PORT_MUX), but nevertheless it's not correct.

Fixes: 3fcece12bc ("net: store port/representator id in metadata_dst")
Signed-off-by: David Lamparter <equinox@diac24.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Sridhar Samudrala <sridhar.samudrala@intel.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21 10:57:38 -07:00
Eric Dumazet
9620fef27e ipv4: convert dst_metrics.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-18 15:14:07 -07:00
Jakub Kicinski
3fcece12bc net: store port/representator id in metadata_dst
Switches and modern SR-IOV enabled NICs may multiplex traffic from Port
representators and control messages over single set of hardware queues.
Control messages and muxed traffic may need ordered delivery.

Those requirements make it hard to comfortably use TC infrastructure today
unless we have a way of attaching metadata to skbs at the upper device.
Because single set of queues is used for many netdevs stopping TC/sched
queues of all of them reliably is impossible and lower device has to
retreat to returning NETDEV_TX_BUSY and usually has to take extra locks on
the fastpath.

This patch attempts to enable port/representative devs to attach metadata
to skbs which carry port id.  This way representatives can be queueless and
all queuing can be performed at the lower netdev in the usual way.

Traffic arriving on the port/representative interfaces will be have
metadata attached and will subsequently be queued to the lower device for
transmission.  The lower device should recognize the metadata and translate
it to HW specific format which is most likely either a special header
inserted before the network headers or descriptor/metadata fields.

Metadata is associated with the lower device by storing the netdev pointer
along with port id so that if TC decides to redirect or mirror the new
netdev will not try to interpret it.

This is mostly for SR-IOV devices since switches don't have lower netdevs
today.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-25 11:42:01 -04:00
Wei Wang
a4c2fd7f78 net: remove DST_NOCACHE flag
DST_NOCACHE flag check has been removed from dst_release() and
dst_hold_safe() in a previous patch because all the dst are now ref
counted properly and can be released based on refcnt only.
Looking at the rest of the DST_NOCACHE use, all of them can now be
removed or replaced with other checks.
So this patch gets rid of all the DST_NOCACHE usage and remove this flag
completely.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:01 -04:00
Wei Wang
b2a9c0ed75 net: remove DST_NOGC flag
Now that all the components have been changed to release dst based on
refcnt only and not depend on dst gc anymore, we can remove the
temporary flag DST_NOGC.

Note that we also need to remove the DST_NOCACHE check in dst_release()
and dst_hold_safe() because now all the dst are released based on refcnt
and behaves as DST_NOCACHE.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:01 -04:00
Wei Wang
5b7c9a8ff8 net: remove dst gc related code
This patch removes all dst gc related code and all the dst free
functions

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:01 -04:00
Wei Wang
52df157f17 xfrm: take refcnt of dst when creating struct xfrm_dst bundle
During the creation of xfrm_dst bundle, always take ref count when
allocating the dst. This way, xfrm_bundle_create() will form a linked
list of dst with dst->child pointing to a ref counted dst child. And
the returned dst pointer is also ref counted. This makes the link from
the flow cache to this dst now ref counted properly.
As the dst is always ref counted properly, we can safely mark
DST_NOGC flag so dst_release() will release dst based on refcnt only.
And dst gc is no longer needed and all dst_free() and its related
function calls should be replaced with dst_release() or
dst_release_immediate().

The special handling logic for dst->child in dst_destroy() can be
replaced with a simple dst_release_immediate() call on the child to
release the whole list linked by dst->child pointer.
Previously used DST_NOHASH flag is not needed anymore as well. The
reason that DST_NOHASH is used in the existing code is mainly to prevent
the dst inserted in the fib tree to be wrongly destroyed during the
deletion of the xfrm_dst bundle. So in the existing code, DST_NOHASH
flag is marked in all the dst children except the one which is in the
fib tree.
However, with this patch series to remove dst gc logic and release dst
only based on ref count, it is safe to release all the children from a
xfrm_dst bundle as long as the dst children are all ref counted
properly which is already the case in the existing code.
So, this patch removes the use of DST_NOHASH flag.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:54:00 -04:00
Wei Wang
4a6ce2b6f2 net: introduce a new function dst_dev_put()
This function should be called when removing routes from fib tree after
the dst gc is no longer in use.
We first mark DST_OBSOLETE_DEAD on this dst to make sure next
dst_ops->check() fails and returns NULL.
Secondly, as we no longer keep the gc_list, we need to properly
release dst->dev right at the moment when the dst is removed from
the fib/fib6 tree.
It does the following:
1. change dst->input and output pointers to dst_discard/dst_dscard_out to
   discard all packets
2. replace dst->dev with loopback interface

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:53:59 -04:00
Wei Wang
5f56f409b5 net: introduce DST_NOGC in dst_release() to destroy dst based on refcnt
The current mechanism of freeing dst is a bit complicated. dst has its
ref count and when user grabs the reference to the dst, the ref count is
properly taken in most cases except in IPv4/IPv6/decnet/xfrm routing
code due to some historic reasons.

If the reference to dst is always taken properly, we should be able to
simplify the logic in dst_release() to destroy dst when dst->__refcnt
drops from 1 to 0. And this should be the only condition to determine
if we can call dst_destroy().
And as dst is always ref counted, there is no need for a dst garbage
list to hold the dst entries that already get removed by the routing
code but are still held by other users. And the task to periodically
check the list to free dst if ref count become 0 is also not needed
anymore.

This patch introduces a temporary flag DST_NOGC(no garbage collector).
If it is set in the dst, dst_release() will call dst_destroy() when
dst->__refcnt drops to 0. dst_hold_safe() will also check for this flag
and do atomic_inc_not_zero() similar as DST_NOCACHE to avoid double free
issue.
This temporary flag is mainly used so that we can make the transition
component by component without breaking other parts.
This flag will be removed after all components are properly transitioned.

This patch also introduces a new function dst_release_immediate() which
destroys dst without waiting on the rcu when refcnt drops to 0. It will
be used in later patches.

Follow-up patches will correct all the places to properly take ref count
on dst and mark DST_NOGC. dst_release() or dst_release_immediate() will
be used to release the dst instead of dst_free() and its related
functions.
And final clean-up patch will remove the DST_NOGC flag.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-17 22:53:59 -04:00
Krister Johansen
f186ce61bb Fix an intermittent pr_emerg warning about lo becoming free.
It looks like this:

Message from syslogd@flamingo at Apr 26 00:45:00 ...
 kernel:unregister_netdevice: waiting for lo to become free. Usage count = 4

They seem to coincide with net namespace teardown.

The message is emitted by netdev_wait_allrefs().

Forced a kdump in netdev_run_todo, but found that the refcount on the lo
device was already 0 at the time we got to the panic.

Used bcc to check the blocking in netdev_run_todo.  The only places
where we're off cpu there are in the rcu_barrier() and msleep() calls.
That behavior is expected.  The msleep time coincides with the amount of
time we spend waiting for the refcount to reach zero; the rcu_barrier()
wait times are not excessive.

After looking through the list of callbacks that the netdevice notifiers
invoke in this path, it appears that the dst_dev_event is the most
interesting.  The dst_ifdown path places a hold on the loopback_dev as
part of releasing the dev associated with the original dst cache entry.
Most of our notifier callbacks are straight-forward, but this one a)
looks complex, and b) places a hold on the network interface in
question.

I constructed a new bcc script that watches various events in the
liftime of a dst cache entry.  Note that dst_ifdown will take a hold on
the loopback device until the invalidated dst entry gets freed.

[      __dst_free] on DST: ffff883ccabb7900 IF tap1008300eth0 invoked at 1282115677036183
    __dst_free
    rcu_nocb_kthread
    kthread
    ret_from_fork
Acked-by: Eric Dumazet <edumazet@google.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-09 12:27:28 -04:00
Eric Dumazet
3fb07daff8 ipv4: add reference counting to metrics
Andrey Konovalov reported crashes in ipv4_mtu()

I could reproduce the issue with KASAN kernels, between
10.246.7.151 and 10.246.7.152 :

1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 &

2) At the same time run following loop :
while :
do
 ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
 ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500
done

Cong Wang attempted to add back rt->fi in commit
82486aa6f1 ("ipv4: restore rt->fi for reference counting")
but this proved to add some issues that were complex to solve.

Instead, I suggested to add a refcount to the metrics themselves,
being a standalone object (in particular, no reference to other objects)

I tried to make this patch as small as possible to ease its backport,
instead of being super clean. Note that we believe that only ipv4 dst
need to take care of the metric refcount. But if this is wrong,
this patch adds the basic infrastructure to extend this to other
families.

Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang
for his efforts on this problem.

Fixes: 2860583fe8 ("ipv4: Kill rt->fi")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26 14:57:07 -04:00
Julian Anastasov
51ce8bd4d1 net: pending_confirm is not used anymore
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
As last step, we can remove the pending_confirm flag.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8 ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf3 ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 13:07:47 -05:00
Paolo Abeni
d71785ffc7 net: add dst_cache to ovs vxlan lwtunnel
In case of UDP traffic with datagram length
below MTU this give about 2% performance increase
when tunneling over ipv4 and about 60% when tunneling
over ipv6

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Suggested-and-acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:21:48 -05:00
Francesco Ruggeri
07a5d38453 net: possible use after free in dst_release
dst_release should not access dst->flags after decrementing
__refcnt to 0. The dst_entry may be in dst_busy_list and
dst_gc_task may dst_destroy it before dst_release gets a chance
to access dst->flags.

Fixes: d69bbf88c8 ("net: fix a race in dst_release()")
Fixes: 27b75c95f1 ("net: avoid RCU for NOCACHE dst")
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-06 15:00:27 -05:00
Eric Dumazet
d69bbf88c8 net: fix a race in dst_release()
Only cpu seeing dst refcount going to 0 can safely
dereference dst->flags.

Otherwise an other cpu might already have freed the dst.

Fixes: 27b75c95f1 ("net: avoid RCU for NOCACHE dst")
Reported-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-09 21:55:48 -05:00
Eric W. Biederman
ede2059dba dst: Pass net into dst->output
The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:27:03 -07:00
Pravin B Shelar
63b6c13dbb tun_dst: Remove opts_size
opts_size is only written and never read. Following patch
removes this unused variable.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-31 21:23:42 -07:00
WANG Cong
e252b3d1a1 route: fix a use-after-free
This patch fixes the following crash:

 general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.2.0-rc7+ #166
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 task: ffff88010656d280 ti: ffff880106570000 task.ti: ffff880106570000
 RIP: 0010:[<ffffffff8182f91b>]  [<ffffffff8182f91b>] dst_destroy+0xa6/0xef
 RSP: 0018:ffff880107603e38  EFLAGS: 00010202
 RAX: 0000000000000001 RBX: ffff8800d225a000 RCX: ffffffff82250fd0
 RDX: 0000000000000001 RSI: ffffffff82250fd0 RDI: 6b6b6b6b6b6b6b6b
 RBP: ffff880107603e58 R08: 0000000000000001 R09: 0000000000000001
 R10: 000000000000b530 R11: ffff880107609000 R12: 0000000000000000
 R13: ffffffff82343c40 R14: 0000000000000000 R15: ffffffff8182fb4f
 FS:  0000000000000000(0000) GS:ffff880107600000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 00007fcabd9d3000 CR3: 00000000d7279000 CR4: 00000000000006e0
 Stack:
  ffffffff82250fd0 ffff8801077d6f00 ffffffff82253c40 ffff8800d225a000
  ffff880107603e68 ffffffff8182fb5d ffff880107603f08 ffffffff810d795e
  ffffffff810d7648 ffff880106574000 ffff88010656d280 ffff88010656d280
 Call Trace:
  <IRQ>
  [<ffffffff8182fb5d>] dst_destroy_rcu+0xe/0x1d
  [<ffffffff810d795e>] rcu_process_callbacks+0x618/0x7eb
  [<ffffffff810d7648>] ? rcu_process_callbacks+0x302/0x7eb
  [<ffffffff8182fb4f>] ? dst_gc_task+0x1eb/0x1eb
  [<ffffffff8107e11b>] __do_softirq+0x178/0x39f
  [<ffffffff8107e52e>] irq_exit+0x41/0x95
  [<ffffffff81a4f215>] smp_apic_timer_interrupt+0x34/0x40
  [<ffffffff81a4d5cd>] apic_timer_interrupt+0x6d/0x80
  <EOI>
  [<ffffffff8100b968>] ? default_idle+0x21/0x32
  [<ffffffff8100b966>] ? default_idle+0x1f/0x32
  [<ffffffff8100bf19>] arch_cpu_idle+0xf/0x11
  [<ffffffff810b0bc7>] default_idle_call+0x1f/0x21
  [<ffffffff810b0dce>] cpu_startup_entry+0x1ad/0x273
  [<ffffffff8102fe67>] start_secondary+0x135/0x156

dst is freed right before lwtstate_put(), this is not correct...

Fixes: 61adedf3e3 ("route: move lwtunnel state to dst_entry")
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 14:29:19 -07:00
Jiri Benc
61adedf3e3 route: move lwtunnel state to dst_entry
Currently, the lwtunnel state resides in per-protocol data. This is
a problem if we encapsulate ipv6 traffic in an ipv4 tunnel (or vice versa).
The xmit function of the tunnel does not know whether the packet has been
routed to it by ipv4 or ipv6, yet it needs the lwtstate data. Moving the
lwtstate data to dst_entry makes such inter-protocol tunneling possible.

As a bonus, this brings a nice diffstat.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-20 15:42:36 -07:00
Alexei Starovoitov
d3aa45ce6b bpf: add helpers to access tunnel metadata
Introduce helpers to let eBPF programs attached to TC manipulate tunnel metadata:
bpf_skb_[gs]et_tunnel_key(skb, key, size, flags)
skb: pointer to skb
key: pointer to 'struct bpf_tunnel_key'
size: size of 'struct bpf_tunnel_key'
flags: room for future extensions

First eBPF program that uses these helpers will allocate per_cpu
metadata_dst structures that will be used on TX.
On RX metadata_dst is allocated by tunnel driver.

Typical usage for TX:
struct bpf_tunnel_key tkey;
... populate tkey ...
bpf_skb_set_tunnel_key(skb, &tkey, sizeof(tkey), 0);
bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);

RX:
struct bpf_tunnel_key tkey = {};
bpf_skb_get_tunnel_key(skb, &tkey, sizeof(tkey), 0);
... lookup or redirect based on tkey ...

'struct bpf_tunnel_key' will be extended in the future by adding
elements to the end and the 'size' argument will indicate which fields
are populated, thereby keeping backwards compatibility.
The 'flags' argument may be used as well when the 'size' is not enough or
to indicate completely different layout of bpf_tunnel_key.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 15:20:22 -07:00
David S. Miller
c5e40ee287 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bridge/br_mdb.c

br_mdb.c conflict was a function call being removed to fix a bug in
'net' but whose signature was changed in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-23 00:41:16 -07:00