Commit Graph

234 Commits

Author SHA1 Message Date
Alexander Lobakin
00d066a4d4 netdev_features: convert NETIF_F_LLTX to dev->lltx
NETIF_F_LLTX can't be changed via Ethtool and is not a feature,
rather an attribute, very similar to IFF_NO_QUEUE (and hot).
Free one netdev_features_t bit and make it a "hot" private flag.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-09-03 11:36:43 +02:00
Breno Leitao
45160cebd6 net: veth: Disable netpoll support
The current implementation of netpoll in veth devices leads to
suboptimal behavior, as it triggers warnings due to the invocation of
__netif_rx() within a softirq context. This is not compliant with
expected practices, as __netif_rx() has the following statement:

	lockdep_assert_once(hardirq_count() | softirq_count());

Given that veth devices typically do not benefit from the
functionalities provided by netpoll, Disable netpoll for veth
interfaces.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20240805094012.1843247-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-06 12:18:30 -07:00
Mina Almasry
173e7622cc Revert "net: mirror skb frag ref/unref helpers"
This reverts commit a580ea994f.

This revert is to resolve Dragos's report of page_pool leak here:
https://lore.kernel.org/lkml/20240424165646.1625690-2-dtatulea@nvidia.com/

The reverted patch interacts very badly with commit 2cc3aeb5ec ("skbuff:
Fix a potential race while recycling page_pool packets"). The reverted
commit hopes that the pp_recycle + is_pp_page variables do not change
between the skb_frag_ref and skb_frag_unref operation. If such a change
occurs, the skb_frag_ref/unref will not operate on the same reference type.
In the case of Dragos's report, the grabbed ref was a pp ref, but the unref
was a page ref, because the pp_recycle setting on the skb was changed.

Attempting to fix this issue on the fly is risky. Lets revert and I hope
to reland this with better understanding and testing to ensure we don't
regress some edge case while streamlining skb reffing.

Fixes: a580ea994f ("net: mirror skb frag ref/unref helpers")
Reported-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://lore.kernel.org/r/20240502175423.2456544-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-03 16:05:53 -07:00
Mina Almasry
a580ea994f net: mirror skb frag ref/unref helpers
Refactor some of the skb frag ref/unref helpers for improved clarity.

Implement napi_pp_get_page() to be the mirror counterpart of
napi_pp_put_page().

Implement skb_page_ref() to be the mirror of skb_page_unref().

Improve __skb_frag_ref() to become a mirror counterpart of
__skb_frag_unref(). Previously unref could handle pp & non-pp pages,
while the ref could only handle non-pp pages. Now both the ref & unref
helpers can correctly handle both pp & non-pp pages.

Now that __skb_frag_ref() can handle both pp & non-pp pages, remove
skb_pp_frag_ref(), and use __skb_frag_ref() instead.  This lets us
remove pp specific handling from skb_try_coalesce.

Additionally, since __skb_frag_ref() can now handle both pp & non-pp
pages, a latent issue in skb_shift() should now be fixed. Previously
this function would do a non-pp ref & pp unref on potential pp frags
(fragfrom). After this patch, skb_shift() should correctly do a pp
ref/unref on pp frags.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240410190505.1225848-3-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 19:29:23 -07:00
Mina Almasry
f6d827b180 net: move skb ref helpers to new header
Add a new header, linux/skbuff_ref.h, which contains all the skb_*_ref()
helpers. Many of the consumers of skbuff.h do not actually use any of
the skb ref helpers, and we can speed up compilation a bit by minimizing
this header file.

Additionally in the later patch in the series we add page_pool support
to skb_frag_ref(), which requires some page_pool dependencies. We can
now add these dependencies to skbuff_ref.h instead of a very ubiquitous
skbuff.h

Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://lore.kernel.org/r/20240410190505.1225848-2-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 19:29:22 -07:00
Ignat Korchagin
d7db7775ea net: veth: do not manipulate GRO when using XDP
Commit d3256efd8e ("veth: allow enabling NAPI even without XDP") tried to fix
the fact that GRO was not possible without XDP, because veth did not use NAPI
without XDP. However, it also introduced the behaviour that GRO is always
enabled, when XDP is enabled.

While it might be desired for most cases, it is confusing for the user at best
as the GRO flag suddenly changes, when an XDP program is attached. It also
introduces some complexities in state management as was partially addressed in
commit fe9f801355 ("net: veth: clear GRO when clearing XDP even when down").

But the biggest problem is that it is not possible to disable GRO at all, when
an XDP program is attached, which might be needed for some use cases.

Fix this by not touching the GRO flag on XDP enable/disable as the code already
supports switching to NAPI if either GRO or XDP is requested.

Link: https://lore.kernel.org/lkml/20240311124015.38106-1-ignat@cloudflare.com/
Fixes: d3256efd8e ("veth: allow enabling NAPI even without XDP")
Fixes: fe9f801355 ("net: veth: clear GRO when clearing XDP even when down")
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-18 12:25:52 +00:00
Jakub Kicinski
65f5dd4f02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/mptcp/protocol.c
  adf1bb78da ("mptcp: fix snd_wnd initialization for passive socket")
  9426ce476a ("mptcp: annotate lockless access for RX path fields")
https://lore.kernel.org/all/20240228103048.19255709@canb.auug.org.au/

Adjacent changes:

drivers/dpll/dpll_core.c
  0d60d8df6f ("dpll: rely on rcu for netdev_dpll_pin()")
  e7f8df0e81 ("dpll: move xa_erase() call in to match dpll_pin_alloc() error path order")

drivers/net/veth.c
  1ce7d306ea ("veth: try harder when allocating queue memory")
  0bef512012 ("net: add netdev_lockdep_set_classes() to virtual drivers")

drivers/net/wireless/intel/iwlwifi/mvm/d3.c
  8c9bef26e9 ("wifi: iwlwifi: mvm: d3: implement suspend with MLO")
  78f65fbf42 ("wifi: iwlwifi: mvm: ensure offloading TID queue exists")

net/wireless/nl80211.c
  f78c137533 ("wifi: nl80211: reject iftype change with mesh ID change")
  414532d8aa ("wifi: cfg80211: use IEEE80211_MAX_MESH_ID_LEN appropriately")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-29 14:24:56 -08:00
Jakub Kicinski
1ce7d306ea veth: try harder when allocating queue memory
struct veth_rq is pretty large, 832B total without debug
options enabled. Since commit under Fixes we try to pre-allocate
enough queues for every possible CPU. Miao Wang reports that
this may lead to order-5 allocations which will fail in production.

Let the allocation fallback to vmalloc() and try harder.
These are the same flags we pass to netdev queue allocation.

Reported-and-tested-by: Miao Wang <shankerwangmiao@gmail.com>
Fixes: 9d3684c24a ("veth: create by default nr_possible_cpus queues")
Link: https://lore.kernel.org/all/5F52CAE2-2FB7-4712-95F1-3312FBBFA8DD@gmail.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240223235908.693010-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-27 13:56:54 +01:00
Eric Dumazet
e353ea9ce4 rtnetlink: prepare nla_put_iflink() to run under RCU
We want to be able to run rtnl_fill_ifinfo() under RCU protection
instead of RTNL in the future.

This patch prepares dev_get_iflink() and nla_put_iflink()
to run either with RTNL or RCU held.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-26 11:46:12 +00:00
Jakub Kicinski
fe9f801355 net: veth: clear GRO when clearing XDP even when down
veth sets NETIF_F_GRO automatically when XDP is enabled,
because both features use the same NAPI machinery.

The logic to clear NETIF_F_GRO sits in veth_disable_xdp() which
is called both on ndo_stop and when XDP is turned off.
To avoid the flag from being cleared when the device is brought
down, the clearing is skipped when IFF_UP is not set.
Bringing the device down should indeed not modify its features.

Unfortunately, this means that clearing is also skipped when
XDP is disabled _while_ the device is down. And there's nothing
on the open path to bring the device features back into sync.
IOW if user enables XDP, disables it and then brings the device
up we'll end up with a stray GRO flag set but no NAPI instances.

We don't depend on the GRO flag on the datapath, so the datapath
won't crash. We will crash (or hang), however, next time features
are sync'ed (either by user via ethtool or peer changing its config).
The GRO flag will go away, and veth will try to disable the NAPIs.
But the open path never created them since XDP was off, the GRO flag
was a stray. If NAPI was initialized before we'll hang in napi_disable().
If it never was we'll crash trying to stop uninitialized hrtimer.

Move the GRO flag updates to the XDP enable / disable paths,
instead of mixing them with the ndo_open / ndo_close paths.

Fixes: d3256efd8e ("veth: allow enabling NAPI even without XDP")
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: syzbot+039399a9b96297ddedca@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-26 11:34:13 +00:00
Lorenzo Bianconi
27accb3cc0 veth: rely on skb_pp_cow_data utility routine
Rely on skb_pp_cow_data utility routine and remove duplicated code.

Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Toke Hoiland-Jorgensen <toke@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/029cc14cce41cb242ee7efdcf32acc81f1ce4e9f.1707729884.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-13 19:22:30 -08:00
Eric Dumazet
0bef512012 net: add netdev_lockdep_set_classes() to virtual drivers
Based on a syzbot report, it appears many virtual
drivers do not yet use netdev_lockdep_set_classes(),
triggerring lockdep false positives.

WARNING: possible recursive locking detected
6.8.0-rc4-next-20240212-syzkaller #0 Not tainted

syz-executor.0/19016 is trying to acquire lock:
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

but task is already holding lock:
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
  lock(_xmit_ETHER#2);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

9 locks held by syz-executor.0/19016:
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6603
  #1: ffffc90000a08c00 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1697
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325

stack backtrace:
CPU: 1 PID: 19016 Comm: syz-executor.0 Not tainted 6.8.0-rc4-next-20240212-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <IRQ>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  check_deadlock kernel/locking/lockdep.c:3062 [inline]
  validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
  __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
  lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
  __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
  _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
  spin_lock include/linux/spinlock.h:351 [inline]
  __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  iptunnel_xmit+0x540/0x9b0 net/ipv4/ip_tunnel_core.c:82
  ip_tunnel_xmit+0x20ee/0x2960 net/ipv4/ip_tunnel.c:831
  erspan_xmit+0x9de/0x1460 net/ipv4/ip_gre.c:720
  __netdev_start_xmit include/linux/netdevice.h:4989 [inline]
  netdev_start_xmit include/linux/netdevice.h:5003 [inline]
  xmit_one net/core/dev.c:3555 [inline]
  dev_hard_start_xmit+0x242/0x770 net/core/dev.c:3571
  sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  igmpv3_send_cr net/ipv4/igmp.c:723 [inline]
  igmp_ifc_timer_expire+0xb71/0xd90 net/ipv4/igmp.c:813
  call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700
  expire_timers kernel/time/timer.c:1751 [inline]
  __run_timers+0x621/0x830 kernel/time/timer.c:2038
  run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051
  __do_softirq+0x2bc/0x943 kernel/softirq.c:554
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1076 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 RIP: 0010:resched_offsets_ok kernel/sched/core.c:10127 [inline]
 RIP: 0010:__might_resched+0x16f/0x780 kernel/sched/core.c:10142
Code: 00 4c 89 e8 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 48 89 44 24 38 0f b6 04 10 84 c0 0f 85 87 04 00 00 41 8b 45 00 c1 e0 08 <01> d8 44 39 e0 0f 85 d6 00 00 00 44 89 64 24 1c 48 8d bc 24 a0 00
RSP: 0018:ffffc9000ee069e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880296a9e00
RDX: dffffc0000000000 RSI: ffff8880296a9e00 RDI: ffffffff8bfe8fa0
RBP: ffffc9000ee06b00 R08: ffffffff82326877 R09: 1ffff11002b5ad1b
R10: dffffc0000000000 R11: ffffed1002b5ad1c R12: 0000000000000000
R13: ffff8880296aa23c R14: 000000000000062a R15: 1ffff92001dc0d44
  down_write+0x19/0x50 kernel/locking/rwsem.c:1578
  kernfs_activate fs/kernfs/dir.c:1403 [inline]
  kernfs_add_one+0x4af/0x8b0 fs/kernfs/dir.c:819
  __kernfs_create_file+0x22e/0x2e0 fs/kernfs/file.c:1056
  sysfs_add_file_mode_ns+0x24a/0x310 fs/sysfs/file.c:307
  create_files fs/sysfs/group.c:64 [inline]
  internal_create_group+0x4f4/0xf20 fs/sysfs/group.c:152
  internal_create_groups fs/sysfs/group.c:192 [inline]
  sysfs_create_groups+0x56/0x120 fs/sysfs/group.c:218
  create_dir lib/kobject.c:78 [inline]
  kobject_add_internal+0x472/0x8d0 lib/kobject.c:240
  kobject_add_varg lib/kobject.c:374 [inline]
  kobject_init_and_add+0x124/0x190 lib/kobject.c:457
  netdev_queue_add_kobject net/core/net-sysfs.c:1706 [inline]
  netdev_queue_update_kobjects+0x1f3/0x480 net/core/net-sysfs.c:1758
  register_queue_kobjects net/core/net-sysfs.c:1819 [inline]
  netdev_register_kobject+0x265/0x310 net/core/net-sysfs.c:2059
  register_netdevice+0x1191/0x19c0 net/core/dev.c:10298
  bond_newlink+0x3b/0x90 drivers/net/bonding/bond_netlink.c:576
  rtnl_newlink_create net/core/rtnetlink.c:3506 [inline]
  __rtnl_newlink net/core/rtnetlink.c:3726 [inline]
  rtnl_newlink+0x158f/0x20a0 net/core/rtnetlink.c:3739
  rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6606
  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
  netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
  netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
  netlink_sendmsg+0xa3c/0xd70 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x221/0x270 net/socket.c:745
  __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
  __do_sys_sendto net/socket.c:2203 [inline]
  __se_sys_sendto net/socket.c:2199 [inline]
  __x64_sys_sendto+0xde/0x100 net/socket.c:2199
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc3fa87fa9c

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240212140700.2795436-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-13 18:45:06 -08:00
Jakub Kicinski
c49b292d03 netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2023-12-18

This PR is larger than usual and contains changes in various parts
of the kernel.

The main changes are:

1) Fix kCFI bugs in BPF, from Peter Zijlstra.

End result: all forms of indirect calls from BPF into kernel
and from kernel into BPF work with CFI enabled. This allows BPF
to work with CONFIG_FINEIBT=y.

2) Introduce BPF token object, from Andrii Nakryiko.

It adds an ability to delegate a subset of BPF features from privileged
daemon (e.g., systemd) through special mount options for userns-bound
BPF FS to a trusted unprivileged application. The design accommodates
suggestions from Christian Brauner and Paul Moore.

Example:
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
             -o delegate_cmds=prog_load:MAP_CREATE \
             -o delegate_progs=kprobe \
             -o delegate_attachs=xdp

3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei.

 - Complete precision tracking support for register spills
 - Fix verification of possibly-zero-sized stack accesses
 - Fix access to uninit stack slots
 - Track aligned STACK_ZERO cases as imprecise spilled registers.
   It improves the verifier "instructions processed" metric from single
   digit to 50-60% for some programs.
 - Fix verifier retval logic

4) Support for VLAN tag in XDP hints, from Larysa Zaremba.

5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu.

End result: better memory utilization and lower I$ miss for calls to BPF
via BPF trampoline.

6) Fix race between BPF prog accessing inner map and parallel delete,
from Hou Tao.

7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu.

It allows BPF interact with IPSEC infra. The intent is to support
software RSS (via XDP) for the upcoming ipsec pcpu work.
Experiments on AWS demonstrate single tunnel pcpu ipsec reaching
line rate on 100G ENA nics.

8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao.

9) BPF file verification via fsverity, from Song Liu.

It allows BPF progs get fsverity digest.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits)
  bpf: Ensure precise is reset to false in __mark_reg_const_zero()
  selftests/bpf: Add more uprobe multi fail tests
  bpf: Fail uprobe multi link with negative offset
  selftests/bpf: Test the release of map btf
  s390/bpf: Fix indirect trampoline generation
  selftests/bpf: Temporarily disable dummy_struct_ops test on s390
  x86/cfi,bpf: Fix bpf_exception_cb() signature
  bpf: Fix dtor CFI
  cfi: Add CFI_NOSEAL()
  x86/cfi,bpf: Fix bpf_struct_ops CFI
  x86/cfi,bpf: Fix bpf_callback_t CFI
  x86/cfi,bpf: Fix BPF JIT call
  cfi: Flip headers
  selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment
  selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test
  selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment
  bpf: Limit the number of kprobes when attaching program to multiple kprobes
  bpf: Limit the number of uprobes when attaching program to multiple uprobes
  bpf: xdp: Register generic_kfunc_set with XDP programs
  selftests/bpf: utilize string values for delegate_xxx mount options
  ...
====================

Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-18 16:46:08 -08:00
Larysa Zaremba
fca783799f veth: Implement VLAN tag XDP hint
In order to test VLAN tag hint in hardware-independent selftests, implement
newly added hint in veth driver.

Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://lore.kernel.org/r/20231205210847.28460-13-larysa.zaremba@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-13 16:16:41 -08:00
Lorenzo Bianconi
a61f46e110 net: veth: fix packet segmentation in veth_convert_skb_to_xdp_buff
Based on the previous allocated packet, page_offset can be not null
in veth_convert_skb_to_xdp_buff routine.
Take into account page fragment offset during the skb paged area copy
in veth_convert_skb_to_xdp_buff().

Fixes: 2d0de67da5 ("net: veth: use newly added page pool API for veth with xdp")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Link: https://lore.kernel.org/r/eddfe549e7e626870071930964ac3c38a1dc8068.1701702000.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-05 19:24:26 -08:00
Lorenzo Bianconi
818ad9cc90 net: veth: fix ethtool stats reporting
Fix a possible misalignment between page_pool stats and tx xdp_stats
reported in veth_get_ethtool_stats routine.
The issue can be reproduced configuring the veth pair with the
following tx/rx queues:

$ip link add v0 numtxqueues 2 numrxqueues 4 type veth peer name v1 \
 numtxqueues 1 numrxqueues 1

and loading a simple XDP program on v0 that just returns XDP_PASS.
In this case on v0 the page_pool stats overwrites tx xdp_stats for queue 1.
Fix the issue incrementing pp_idx of dev->real_num_tx_queues * VETH_TQ_STATS_LEN
since we always report xdp_stats for all tx queues in ethtool.

Fixes: 4fc418053e ("net: veth: add page_pool stats")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/c5b5d0485016836448453f12846c7c4ab75b094a.1700593593.git.lorenzo@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-23 13:23:59 +01:00
Peilin Ye
6f2684bf2b veth: Use tstats per-CPU traffic counters
Currently veth devices use the lstats per-CPU traffic counters, which only
cover TX traffic. veth_get_stats64() actually populates RX stats of a veth
device from its peer's TX counters, based on the assumption that a veth
device can _only_ receive packets from its peer, which is no longer true:

For example, recent CNIs (like Cilium) can use the bpf_redirect_peer() BPF
helper to redirect traffic from NIC's tc ingress to veth's tc ingress (in
a different netns), skipping veth's peer device. Unfortunately, this kind
of traffic isn't currently accounted for in veth's RX stats.

In preparation for the fix, use tstats (instead of lstats) to maintain
both RX and TX counters for each veth device. We'll use RX counters for
bpf_redirect_peer() traffic, and keep using TX counters for the usual
"peer-to-peer" traffic. In veth_get_stats64(), calculate RX stats by
_adding_ RX count to peer's TX count, in order to cover both kinds of
traffic.

veth_stats_rx() might need a name change (perhaps to "veth_stats_xdp()")
for less confusion, but let's leave it to another patch to keep the fix
minimal.

Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20231114004220.6495-5-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-11-20 10:15:16 -08:00
Daniel Borkmann
34d21de99c net: Move {l,t,d}stats allocation to core and convert veth & vrf
Move {l,t,d}stats allocation to the core and let netdevs pick the stats
type they need. That way the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc) - all happening in the core.

Co-developed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Cc: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-11-20 10:15:16 -08:00
Yunsheng Lin
2d0de67da5 net: veth: use newly added page pool API for veth with xdp
Use page_pool_alloc() API to allocate memory with least
memory utilization and performance penalty.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
CC: Lorenzo Bianconi <lorenzo@kernel.org>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: Liang Chen <liangchen.linux@gmail.com>
CC: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20231020095952.11055-6-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-23 19:14:49 -07:00
Toke Høiland-Jørgensen
7a6102aa6d veth: Update XDP feature set when bringing up device
There's an early return in veth_set_features() if the device is in a down
state, which leads to the XDP feature flags not being updated when enabling
GRO while the device is down. Which in turn leads to XDP_REDIRECT not
working, because the redirect code now checks the flags.

Fix this by updating the feature flags after bringing the device up.

Before this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	no
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	no

After this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	yes
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	yes

Fixes: fccca038f3 ("veth: take into account device reconfiguration for xdp_features flag")
Fixes: 66c0e13ad2 ("drivers: net: turn on XDP features")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20230911135826.722295-1-toke@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-12 16:32:56 +02:00
Liang Chen
151e887d8f veth: Fixing transmit return status for dropped packets
The veth_xmit function returns NETDEV_TX_OK even when packets are dropped.
This behavior leads to incorrect calculations of statistics counts, as
well as things like txq->trans_start updates.

Fixes: e314dbdc1c ("[NET]: Virtual ethernet device driver.")
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-04 06:52:39 +01:00
Liang Chen
215eb9f962 veth: Avoid NAPI scheduling on failed SKB forwarding
When an skb fails to be forwarded to the peer(e.g., skb data buffer
length exceeds MTU), it will not be added to the peer's receive queue.
Therefore, we should schedule the peer's NAPI poll function only when
skb forwarding is successful to avoid unnecessary overhead.

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Link: https://lore.kernel.org/r/20230824123131.7673-1-liangchen.linux@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-25 18:52:11 -07:00
Jakub Kicinski
57ce6427e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

include/net/inet_sock.h
  f866fbc842 ("ipv4: fix data-races around inet->inet_id")
  c274af2242 ("inet: introduce inet->inet_flags")
https://lore.kernel.org/all/679ddff6-db6e-4ff6-b177-574e90d0103d@tessares.net/

Adjacent changes:

drivers/net/bonding/bond_alb.c
  e74216b8de ("bonding: fix macvlan over alb bond support")
  f11e5bd159 ("bonding: support balance-alb with openvswitch")

drivers/net/ethernet/broadcom/bgmac.c
  d6499f0b7c ("net: bgmac: Return PTR_ERR() for fixed_phy_register()")
  23a14488ea ("net: bgmac: Fix return value check for fixed_phy_register()")

drivers/net/ethernet/broadcom/genet/bcmmii.c
  32bbe64a13 ("net: bcmgenet: Fix return value check for fixed_phy_register()")
  acf50d1adb ("net: bcmgenet: Return PTR_ERR() for fixed_phy_register()")

net/sctp/socket.c
  f866fbc842 ("ipv4: fix data-races around inet->inet_id")
  b09bde5c35 ("inet: move inet->mc_loop to inet->inet_frags")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-24 10:51:39 -07:00
Jakub Kicinski
f534f6581e net: validate veth and vxcan peer ifindexes
veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.

Using iproute2 with user-space-level checking removed:

Before:

  # ./ip link add index 10 type veth peer index -1
  # ip link show
  1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  2: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
  10: veth1@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
  -1: veth0@veth1: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff

Now:

  $ ./ip link add index 10 type veth peer index -1
  Error: ifindex can't be negative.

This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.

Fixes: e6f8f1a739 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-20 11:40:03 +01:00
Jakub Kicinski
7ff57803d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/sfc/tc.c
  fa165e1949 ("sfc: don't unregister flow_indr if it was never registered")
  3bf969e88a ("sfc: add MAE table machinery for conntrack table")
https://lore.kernel.org/all/20230818112159.7430e9b4@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-18 12:44:56 -07:00
Liang Chen
8a519a5725 net: veth: Page pool creation error handling for existing pools only
The failure handling procedure destroys page pools for all queues,
including those that haven't had their page pool created yet. this patch
introduces necessary adjustments to prevent potential risks and
inconsistency with the error handling behavior.

Fixes: 0ebab78cbc ("net: veth: add page_pool for page recycling")
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Link: https://lore.kernel.org/r/20230812023016.10553-1-liangchen.linux@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-14 19:26:19 -07:00
Yunsheng Lin
a9ca9f9cef page_pool: split types and declarations from page_pool.h
Split types and pure function declarations from page_pool.h
and add them in page_page/types.h, so that C sources can
include page_pool.h and headers should generally only include
page_pool/types.h as suggested by jakub.
Rename page_pool.h to page_pool/helpers.h to have both in
one place.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20230804180529.2483231-2-aleksander.lobakin@intel.com
[Jakub: change microsoft/mana, fix kdoc paths in Documentation]
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-07 13:05:19 -07:00
Lorenzo Bianconi
5e316a818e net: veth: make PAGE_POOL_STATS optional
Since veth is very likely to be enabled and there are some drivers
(e.g. mlx5) where CONFIG_PAGE_POOL_STATS is optional, make
CONFIG_PAGE_POOL_STATS optional for veth too in order to keep it
optional instead of required.

Suggested-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-10 09:57:39 +01:00
Lorenzo Bianconi
9d142ed484 net: veth: rely on napi_build_skb in veth_convert_skb_to_xdp_buff
Since veth_convert_skb_to_xdp_buff routine runs in veth_poll() NAPI,
rely on napi_build_skb() instead of build_skb() to reduce skb allocation
cost.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Link: https://lore.kernel.org/r/0f822c0b72f8b71555c11745cb8fb33399d02de9.1683578488.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-09 20:10:36 -07:00
Lorenzo Bianconi
4fc418053e net: veth: add page_pool stats
Introduce page_pool stats support to report info about local page_pool
through ethtool

Tested-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-24 18:07:08 -07:00
Lorenzo Bianconi
0ebab78cbc net: veth: add page_pool for page recycling
Introduce page_pool support in veth driver in order to recycle pages
in veth_convert_skb_to_xdp_buff routine and avoid reallocating the skb
through the page allocator.
The patch has been tested sending tcp traffic to a veth pair where the
remote peer is running a simple xdp program just returning xdp_pass:

veth upstream codebase:
MTU 1500B: ~ 8Gbps
MTU 8000B: ~ 13.9Gbps

veth upstream codebase + pp support:
MTU 1500B: ~ 9.2Gbps
MTU 8000B: ~ 16.2Gbps

Tested-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-24 18:07:08 -07:00
Lorenzo Bianconi
8267fc71ab veth: take into account peer device for NETDEV_XDP_ACT_NDO_XMIT xdp_features flag
For veth pairs, NETDEV_XDP_ACT_NDO_XMIT is supported by the current
device if the peer one is running a XDP program or if it has GRO enabled.
Fix the xdp_features flags reporting considering peer device and not
current one for NETDEV_XDP_ACT_NDO_XMIT.

Fixes: fccca038f3 ("veth: take into account device reconfiguration for xdp_features flag")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/4f1ca6f6f6b42ae125bfdb5c7782217c83968b2e.1681767806.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-18 11:10:58 -07:00
Jesper Dangaard Brouer
96b1a098f3 veth: bpf_xdp_metadata_rx_hash add xdp rss hash type
Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type.

The veth driver currently only support XDP-hints based on SKB code path.
The SKB have lost information about the RSS hash type, by compressing
the information down to a single bitfield skb->l4_hash, that only knows
if this was a L4 hash value.

In preparation for veth, the xdp_rss_hash_type have an L4 indication
bit that allow us to return a meaningful L4 indication when working
with SKB based packets.

Fixes: 306531f024 ("veth: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132893055.340624.16209448340644513469.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-13 11:15:10 -07:00
Jesper Dangaard Brouer
0cd917a4a8 xdp: rss hash types representation
The RSS hash type specifies what portion of packet data NIC hardware used
when calculating RSS hash value. The RSS types are focused on Internet
traffic protocols at OSI layers L3 and L4. L2 (e.g. ARP) often get hash
value zero and no RSS type. For L3 focused on IPv4 vs. IPv6, and L4
primarily TCP vs UDP, but some hardware supports SCTP.

Hardware RSS types are differently encoded for each hardware NIC. Most
hardware represent RSS hash type as a number. Determining L3 vs L4 often
requires a mapping table as there often isn't a pattern or sorting
according to ISO layer.

The patch introduce a XDP RSS hash type (enum xdp_rss_hash_type) that
contains both BITs for the L3/L4 types, and combinations to be used by
drivers for their mapping tables. The enum xdp_rss_type_bits get exposed
to BPF via BTF, and it is up to the BPF-programmer to match using these
defines.

This proposal change the kfunc API bpf_xdp_metadata_rx_hash() adding
a pointer value argument for provide the RSS hash type.
Change signature for all xmo_rx_hash calls in drivers to make it compile.

The RSS type implementations for each driver comes as separate patches.

Fixes: 3d76a4d3d4 ("bpf: XDP metadata RX kfuncs")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/168132892042.340624.582563003880565460.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-13 11:15:10 -07:00
Jakub Kicinski
1b4ae19e43 bpf-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2023-03-23

We've added 8 non-merge commits during the last 13 day(s) which contain
a total of 21 files changed, 238 insertions(+), 161 deletions(-).

The main changes are:

1) Fix verification issues in some BPF programs due to their stack usage
   patterns, from Eduard Zingerman.

2) Fix to add missing overflow checks in xdp_umem_reg and return an error
   in such case, from Kal Conley.

3) Fix and undo poisoning of strlcpy in libbpf given it broke builds for
   libcs which provided the former like uClibc-ng, from Jesus Sanchez-Palencia.

4) Fix insufficient bpf_jit_limit default to avoid users running into hard
   to debug seccomp BPF errors, from Daniel Borkmann.

5) Fix driver return code when they don't support a bpf_xdp_metadata kfunc
   to make it unambiguous from other errors, from Jesper Dangaard Brouer.

6) Two BPF selftest fixes to address compilation errors from recent changes
   in kernel structures, from Alexei Starovoitov.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support
  bpf: Adjust insufficient default bpf_jit_limit
  xsk: Add missing overflow check in xdp_umem_reg
  selftests/bpf: Fix progs/test_deny_namespace.c issues.
  selftests/bpf: Fix progs/find_vma_fail1.c build error.
  libbpf: Revert poisoning of strlcpy
  selftests/bpf: Tests for uninitialized stack reads
  bpf: Allow reads from uninit stack
====================

Link: https://lore.kernel.org/r/20230323225221.6082-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-23 16:03:33 -07:00
Jesper Dangaard Brouer
915efd8a44 xdp: bpf_xdp_metadata use EOPNOTSUPP for no driver support
When driver doesn't implement a bpf_xdp_metadata kfunc the fallback
implementation returns EOPNOTSUPP, which indicate device driver doesn't
implement this kfunc.

Currently many drivers also return EOPNOTSUPP when the hint isn't
available, which is ambiguous from an API point of view. Instead
change drivers to return ENODATA in these cases.

There can be natural cases why a driver doesn't provide any hardware
info for a specific hint, even on a frame to frame basis (e.g. PTP).
Lets keep these cases as separate return codes.

When describing the return values, adjust the function kernel-doc layout
to get proper rendering for the return values.

Fixes: ab46182d0d ("net/mlx4_en: Support RX XDP metadata")
Fixes: bc8d405b1b ("net/mlx5e: Support RX XDP metadata")
Fixes: 306531f024 ("veth: Support RX XDP metadata")
Fixes: 3d76a4d3d4 ("bpf: XDP metadata RX kfuncs")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/167940675120.2718408.8176058626864184420.stgit@firesoul
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-22 09:11:09 -07:00
Shawn Bohrer
7c10131803 veth: Fix use after free in XDP_REDIRECT
Commit 718a18a0c8 ("veth: Rework veth_xdp_rcv_skb in order
to accept non-linear skb") introduced a bug where it tried to
use pskb_expand_head() if the headroom was less than
XDP_PACKET_HEADROOM.  This however uses kmalloc to expand the head,
which will later allow consume_skb() to free the skb while is it still
in use by AF_XDP.

Previously if the headroom was less than XDP_PACKET_HEADROOM we
continued on to allocate a new skb from pages so this restores that
behavior.

BUG: KASAN: use-after-free in __xsk_rcv+0x18d/0x2c0
Read of size 78 at addr ffff888976250154 by task napi/iconduit-g/148640

CPU: 5 PID: 148640 Comm: napi/iconduit-g Kdump: loaded Tainted: G           O       6.1.4-cloudflare-kasan-2023.1.2 #1
Hardware name: Quanta Computer Inc. QuantaPlex T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018
Call Trace:
  <TASK>
  dump_stack_lvl+0x34/0x48
  print_report+0x170/0x473
  ? __xsk_rcv+0x18d/0x2c0
  kasan_report+0xad/0x130
  ? __xsk_rcv+0x18d/0x2c0
  kasan_check_range+0x149/0x1a0
  memcpy+0x20/0x60
  __xsk_rcv+0x18d/0x2c0
  __xsk_map_redirect+0x1f3/0x490
  ? veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]
  xdp_do_redirect+0x5ca/0xd60
  veth_xdp_rcv_skb+0x935/0x1ba0 [veth]
  ? __netif_receive_skb_list_core+0x671/0x920
  ? veth_xdp+0x670/0x670 [veth]
  veth_xdp_rcv+0x304/0xa20 [veth]
  ? do_xdp_generic+0x150/0x150
  ? veth_xdp_rcv_one+0xde0/0xde0 [veth]
  ? _raw_spin_lock_bh+0xe0/0xe0
  ? newidle_balance+0x887/0xe30
  ? __perf_event_task_sched_in+0xdb/0x800
  veth_poll+0x139/0x571 [veth]
  ? veth_xdp_rcv+0xa20/0xa20 [veth]
  ? _raw_spin_unlock+0x39/0x70
  ? finish_task_switch.isra.0+0x17e/0x7d0
  ? __switch_to+0x5cf/0x1070
  ? __schedule+0x95b/0x2640
  ? io_schedule_timeout+0x160/0x160
  __napi_poll+0xa1/0x440
  napi_threaded_poll+0x3d1/0x460
  ? __napi_poll+0x440/0x440
  ? __kthread_parkme+0xc6/0x1f0
  ? __napi_poll+0x440/0x440
  kthread+0x2a2/0x340
  ? kthread_complete_and_exit+0x20/0x20
  ret_from_fork+0x22/0x30
  </TASK>

Freed by task 148640:
  kasan_save_stack+0x23/0x50
  kasan_set_track+0x21/0x30
  kasan_save_free_info+0x2a/0x40
  ____kasan_slab_free+0x169/0x1d0
  slab_free_freelist_hook+0xd2/0x190
  __kmem_cache_free+0x1a1/0x2f0
  skb_release_data+0x449/0x600
  consume_skb+0x9f/0x1c0
  veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]
  veth_xdp_rcv+0x304/0xa20 [veth]
  veth_poll+0x139/0x571 [veth]
  __napi_poll+0xa1/0x440
  napi_threaded_poll+0x3d1/0x460
  kthread+0x2a2/0x340
  ret_from_fork+0x22/0x30

The buggy address belongs to the object at ffff888976250000
  which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 340 bytes inside of
  2048-byte region [ffff888976250000, ffff888976250800)

The buggy address belongs to the physical page:
page:00000000ae18262a refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x976250
head:00000000ae18262a order:3 compound_mapcount:0 compound_pincount:0
flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff)
raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004cf00
raw: 0000000000000000 0000000080080008 00000002ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff888976250000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888976250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff888976250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                  ^
  ffff888976250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff888976250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 718a18a0c8 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb")
Signed-off-by: Shawn Bohrer <sbohrer@cloudflare.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Acked-by: Toshiaki Makita <toshiaki.makita1@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@kernel.org>
Link: https://lore.kernel.org/r/20230314153351.2201328-1-sbohrer@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15 21:11:06 -07:00
Lorenzo Bianconi
5ce76fe1ee veth: rely on rtnl_dereference() instead of on rcu_dereference() in veth_set_xdp_features()
Fix the following kernel warning in veth_set_xdp_features routine
relying on rtnl_dereference() instead of on rcu_dereference():

=============================
WARNING: suspicious RCU usage
6.3.0-rc1-00144-g064d70527aaa #149 Not tainted
-----------------------------
drivers/net/veth.c:1265 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by ip/135:
(net/core/rtnetlink.c:6172)

stack backtrace:
CPU: 1 PID: 135 Comm: ip Not tainted 6.3.0-rc1-00144-g064d70527aaa #149
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1
04/01/2014
Call Trace:
 <TASK>
dump_stack_lvl (lib/dump_stack.c:107)
lockdep_rcu_suspicious (include/linux/context_tracking.h:152)
veth_set_xdp_features (drivers/net/veth.c:1265 (discriminator 9))
veth_newlink (drivers/net/veth.c:1892)
? veth_set_features (drivers/net/veth.c:1774)
? kasan_save_stack (mm/kasan/common.c:47)
? kasan_save_stack (mm/kasan/common.c:46)
? kasan_set_track (mm/kasan/common.c:52)
? alloc_netdev_mqs (include/linux/slab.h:737)
? rcu_read_lock_sched_held (kernel/rcu/update.c:125)
? trace_kmalloc (include/trace/events/kmem.h:54)
? __xdp_rxq_info_reg (net/core/xdp.c:188)
? alloc_netdev_mqs (net/core/dev.c:10657)
? rtnl_create_link (net/core/rtnetlink.c:3312)
rtnl_newlink_create (net/core/rtnetlink.c:3440)
? rtnl_link_get_net_capable.constprop.0 (net/core/rtnetlink.c:3391)
__rtnl_newlink (net/core/rtnetlink.c:3657)
? lock_downgrade (kernel/locking/lockdep.c:5321)
? rtnl_link_unregister (net/core/rtnetlink.c:3487)
rtnl_newlink (net/core/rtnetlink.c:3671)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6174)
? rtnl_link_fill (net/core/rtnetlink.c:6070)
? mark_usage (kernel/locking/lockdep.c:4914)
? mark_usage (kernel/locking/lockdep.c:4914)
netlink_rcv_skb (net/netlink/af_netlink.c:2574)
? rtnl_link_fill (net/core/rtnetlink.c:6070)
? netlink_ack (net/netlink/af_netlink.c:2551)
? lock_acquire (kernel/locking/lockdep.c:467)
? net_generic (include/linux/rcupdate.h:805)
? netlink_deliver_tap (include/linux/rcupdate.h:805)
netlink_unicast (net/netlink/af_netlink.c:1340)
? netlink_attachskb (net/netlink/af_netlink.c:1350)
netlink_sendmsg (net/netlink/af_netlink.c:1942)
? netlink_unicast (net/netlink/af_netlink.c:1861)
? netlink_unicast (net/netlink/af_netlink.c:1861)
sock_sendmsg (net/socket.c:727)
____sys_sendmsg (net/socket.c:2501)
? kernel_sendmsg (net/socket.c:2448)
? __copy_msghdr (net/socket.c:2428)
___sys_sendmsg (net/socket.c:2557)
? mark_usage (kernel/locking/lockdep.c:4914)
? do_recvmmsg (net/socket.c:2544)
? lock_acquire (kernel/locking/lockdep.c:467)
? find_held_lock (kernel/locking/lockdep.c:5159)
? __lock_release (kernel/locking/lockdep.c:5345)
? __might_fault (mm/memory.c:5625)
? lock_downgrade (kernel/locking/lockdep.c:5321)
? __fget_light (include/linux/atomic/atomic-arch-fallback.h:227)
__sys_sendmsg (include/linux/file.h:31)
? __sys_sendmsg_sock (net/socket.c:2572)
? rseq_get_rseq_cs (kernel/rseq.c:275)
? lockdep_hardirqs_on_prepare.part.0 (kernel/locking/lockdep.c:4263)
do_syscall_64 (arch/x86/entry/common.c:50)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7f0d1aadeb17
Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e
fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10

Fixes: fccca038f3 ("veth: take into account device reconfiguration for xdp_features flag")
Suggested-by: Eric Dumazet <edumazet@google.com>
Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/netdev/cover.1678364612.git.lorenzo@kernel.org/T/#me4c9d8e985ec7ebee981cfdb5bc5ec651ef4035d
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reported-by: syzbot+c3d0d9c42d59ff644ea6@syzkaller.appspotmail.com
Reviewed-by: Eric Dumazet <edumazet@google.com>
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/dfd6a9a7d85e9113063165e1f47b466b90ad7b8a.1678748579.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15 00:38:33 -07:00
Lorenzo Bianconi
fccca038f3 veth: take into account device reconfiguration for xdp_features flag
Take into account tx/rx queues reconfiguration setting device
xdp_features flag. Moreover consider NETIF_F_GRO flag in order to enable
ndo_xdp_xmit callback.

Fixes: 66c0e13ad2 ("drivers: net: turn on XDP features")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-10 21:33:48 -08:00
Marek Majtyka
66c0e13ad2 drivers: net: turn on XDP features
A summary of the flags being set for various drivers is given below.
Note that XDP_F_REDIRECT_TARGET and XDP_F_FRAG_TARGET are features
that can be turned off and on at runtime. This means that these flags
may be set and unset under RTNL lock protection by the driver. Hence,
READ_ONCE must be used by code loading the flag value.

Also, these flags are not used for synchronization against the availability
of XDP resources on a device. It is merely a hint, and hence the read
may race with the actual teardown of XDP resources on the device. This
may change in the future, e.g. operations taking a reference on the XDP
resources of the driver, and in turn inhibiting turning off this flag.
However, for now, it can only be used as a hint to check whether device
supports becoming a redirection target.

Turn 'hw-offload' feature flag on for:
 - netronome (nfp)
 - netdevsim.

Turn 'native' and 'zerocopy' features flags on for:
 - intel (i40e, ice, ixgbe, igc)
 - mellanox (mlx5).
 - stmmac
 - netronome (nfp)

Turn 'native' features flags on for:
 - amazon (ena)
 - broadcom (bnxt)
 - freescale (dpaa, dpaa2, enetc)
 - funeth
 - intel (igb)
 - marvell (mvneta, mvpp2, octeontx2)
 - mellanox (mlx4)
 - mtk_eth_soc
 - qlogic (qede)
 - sfc
 - socionext (netsec)
 - ti (cpsw)
 - tap
 - tsnep
 - veth
 - xen
 - virtio_net.

Turn 'basic' (tx, pass, aborted and drop) features flags on for:
 - netronome (nfp)
 - cavium (thunder)
 - hyperv.

Turn 'redirect_target' feature flag on for:
 - amanzon (ena)
 - broadcom (bnxt)
 - freescale (dpaa, dpaa2)
 - intel (i40e, ice, igb, ixgbe)
 - ti (cpsw)
 - marvell (mvneta, mvpp2)
 - sfc
 - socionext (netsec)
 - qlogic (qede)
 - mellanox (mlx5)
 - tap
 - veth
 - virtio_net
 - xen

Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Marek Majtyka <alardam@gmail.com>
Link: https://lore.kernel.org/r/3eca9fafb308462f7edb1f58e451d59209aa07eb.1675245258.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-02 20:48:23 -08:00
Stanislav Fomichev
306531f024 veth: Support RX XDP metadata
The goal is to enable end-to-end testing of the metadata for AF_XDP.

Cc: John Fastabend <john.fastabend@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-11-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 09:38:11 -08:00
Stanislav Fomichev
fefb695a74 veth: Introduce veth_xdp_buff wrapper for xdp_buff
No functional changes. Boilerplate to allow stuffing more data after xdp_buff.

Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Anatoly Burakov <anatoly.burakov@intel.com>
Cc: Alexander Lobakin <alexandr.lobakin@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Cc: Maryam Tahhan <mtahhan@redhat.com>
Cc: xdp-hints@xdp-project.net
Cc: netdev@vger.kernel.org
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20230119221536.3349901-10-sdf@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-01-23 09:38:11 -08:00
Shawn Bohrer
fa349e396e veth: Fix race with AF_XDP exposing old or uninitialized descriptors
When AF_XDP is used on on a veth interface the RX ring is updated in two
steps.  veth_xdp_rcv() removes packet descriptors from the FILL ring
fills them and places them in the RX ring updating the cached_prod
pointer.  Later xdp_do_flush() syncs the RX ring prod pointer with the
cached_prod pointer allowing user-space to see the recently filled in
descriptors.  The rings are intended to be SPSC, however the existing
order in veth_poll allows the xdp_do_flush() to run concurrently with
another CPU creating a race condition that allows user-space to see old
or uninitialized descriptors in the RX ring.  This bug has been observed
in production systems.

To summarize, we are expecting this ordering:

CPU 0 __xsk_rcv_zc()
CPU 0 __xsk_map_flush()
CPU 2 __xsk_rcv_zc()
CPU 2 __xsk_map_flush()

But we are seeing this order:

CPU 0 __xsk_rcv_zc()
CPU 2 __xsk_rcv_zc()
CPU 0 __xsk_map_flush()
CPU 2 __xsk_map_flush()

This occurs because we rely on NAPI to ensure that only one napi_poll
handler is running at a time for the given veth receive queue.
napi_schedule_prep() will prevent multiple instances from getting
scheduled. However calling napi_complete_done() signals that this
napi_poll is complete and allows subsequent calls to
napi_schedule_prep() and __napi_schedule() to succeed in scheduling a
concurrent napi_poll before the xdp_do_flush() has been called.  For the
veth driver a concurrent call to napi_schedule_prep() and
__napi_schedule() can occur on a different CPU because the veth xmit
path can additionally schedule a napi_poll creating the race.

The fix as suggested by Magnus Karlsson, is to simply move the
xdp_do_flush() call before napi_complete_done().  This syncs the
producer ring pointers before another instance of napi_poll can be
scheduled on another CPU.  It will also slightly improve performance by
moving the flush closer to when the descriptors were placed in the
RX ring.

Fixes: d1396004dd ("veth: Add XDP TX and REDIRECT")
Suggested-by: Magnus Karlsson <magnus.karlsson@gmail.com>
Signed-off-by: Shawn Bohrer <sbohrer@cloudflare.com>
Link: https://lore.kernel.org/r/20221220185903.1105011-1-sbohrer@cloudflare.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-12-22 15:06:10 +01:00
Heng Qi
5e8d3dc73e Revert "veth: Avoid drop packets when xdp_redirect performs"
This reverts commit 2e0de6366a.

Based on the issues reported by John and Paolo and their comments,
this patch and the corresponding fix 5e5dc33d5d are reverted, and
we'll remake it.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22 20:42:08 -08:00
Heng Qi
b535d681ad Revert "bpf: veth driver panics when xdp prog attached before veth_open"
This reverts commit 5e5dc33d5d.

This patch fixes the panic maked by 2e0de6366a. Now Paolo
and Toke suggest reverting the patch 2e0de6366a and making
it stronger, so do this first.

Signed-off-by: Heng Qi <hengqi@linux.alibaba.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-22 20:42:08 -08:00
John Fastabend
5e5dc33d5d bpf: veth driver panics when xdp prog attached before veth_open
The following panic is observed when bringing up (veth_open) a veth device
that has an XDP program attached.

[   61.519185] kernel BUG at net/core/dev.c:6442!
[   61.519456] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[   61.519752] CPU: 0 PID: 408 Comm: ip Tainted: G        W          6.1.0-rc2-185930-gd9095f92950b-dirty #26
[   61.520288] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
[   61.520806] RIP: 0010:napi_enable+0x3d/0x40
[   61.521077] Code: f6 f6 80 61 08 00 00 02 74 0d 48 83 bf 88 01 00 00 00 74 03 80 cd 01 48 89 d0 f0 48 0f b1 4f 10 48 39 c2 75 c8 c3 cc cc cc cc <0f> 0b 90 48 8b 87 b0 00 00 00 48 81 c7 b0 00 00 00 45 31 c0 48 39
[   61.522226] RSP: 0018:ffffbc9800cc36f8 EFLAGS: 00010246
[   61.522557] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000001
[   61.523004] RDX: 0000000000000010 RSI: ffffffff8b0de852 RDI: ffff9f03848e5000
[   61.523452] RBP: 0000000000000000 R08: 0000000000000800 R09: 0000000000000000
[   61.523899] R10: ffff9f0384a96800 R11: ffffffffffa48061 R12: ffff9f03849c3000
[   61.524345] R13: 0000000000000300 R14: ffff9f03848e5000 R15: 0000001000000100
[   61.524792] FS:  00007f58cb64d2c0(0000) GS:ffff9f03bbc00000(0000) knlGS:0000000000000000
[   61.525301] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   61.525673] CR2: 00007f6cc629b498 CR3: 000000010498c000 CR4: 00000000000006f0
[   61.526121] Call Trace:
[   61.526284]  <TASK>
[   61.526425]  __veth_napi_enable_range+0xd6/0x230
[   61.526723]  veth_enable_xdp+0xd0/0x160
[   61.526969]  veth_open+0x2e/0xc0
[   61.527180]  __dev_open+0xe2/0x1b0
[   61.527405]  __dev_change_flags+0x1a1/0x210
[   61.527673]  dev_change_flags+0x1c/0x60

This happens because we are calling veth_napi_enable() on already enabled
queues. The root cause is in commit 2e0de6366a changed the control logic
dropping this case,

        if (priv->_xdp_prog) {
                err = veth_enable_xdp(dev);
                if (err)
                        return err;
-       } else if (veth_gro_requested(dev)) {
+               /* refer to the logic in veth_xdp_set() */
+               if (!rtnl_dereference(peer_rq->napi)) {
+                       err = veth_napi_enable(peer);
+                       if (err)
+                               return err;
+               }

so that now veth_napi_enable is called if the peer has not yet
initialiazed its peer_rq->napi. The issue is this will happen
even if the NIC is not up. Then in veth_enable_xdp just above
we have similar path,

  veth_enable_xdp
   napi_already_on = (dev->flags & IFF_UP) && rcu_access_pointer(rq->napi)
    err = veth_enable_xdp_range(dev, 0, dev->real_num_rx_queues, napi_already_on);

The trouble is an xdp prog is assigned before bringing the device up each
of the veth_open path will enable the peers xdp napi structs. But then when
we bring the peer up it will similar try to enable again because from
veth_open the IFF_UP flag is not set until after the op in __dev_open so
we believe napi_alread_on = false.

To fix this just drop the IFF_UP test and rely on checking if the napi
struct is enabled. This also matches the peer check in veth_xdp for
disabling.

To reproduce run ./test_xdp_meta.sh I found adding Cilium/Tetragon tests
for XDP.

Fixes: 2e0de6366a ("veth: Avoid drop packets when xdp_redirect performs")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20221108221650.808950-2-john.fastabend@gmail.com
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-11-09 21:02:24 -08:00
Heng Qi
2e0de6366a veth: Avoid drop packets when xdp_redirect performs
In the current processing logic, when xdp_redirect occurs, it transmits
the xdp frame based on napi.

If napi of the peer veth is not ready, the veth will drop the packets.
This doesn't meet our expectations.

In this context, we enable napi of the peer veth automatically when the
veth loads the xdp. Then if the veth unloads the xdp, we need to
correctly judge whether to disable napi of the peer veth, because the peer
veth may have loaded xdp, or even the user has enabled GRO.

Signed-off-by: Heng Qi <henqqi@linux.alibaba.com>
Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-02 12:07:10 +00:00
Hangbin Liu
1d997f1013 rtnetlink: pass netlink message header and portid to rtnl_configure_link()
This patch pass netlink message header and portid to rtnl_configure_link()
All the functions in this call chain need to add the parameters so we can
use them in the last call rtnl_notify(), and notify the userspace about
the new link info if NLM_F_ECHO flag is set.

- rtnl_configure_link()
  - __dev_notify_flags()
    - rtmsg_ifinfo()
      - rtmsg_ifinfo_event()
        - rtmsg_ifinfo_build_skb()
        - rtmsg_ifinfo_send()
	  - rtnl_notify()

Also move __dev_notify_flags() declaration to net/core/dev.h, as Jakub
suggested.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-31 18:10:21 -07:00
Thomas Gleixner
068c38ad88 net: Remove the obsolte u64_stats_fetch_*_irq() users (drivers).
Now that the 32bit UP oddity is gone and 32bit uses always a sequence
count, there is no need for the fetch_irq() variants anymore.

Convert to the regular interface.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-28 20:13:54 -07:00
Jakub Kicinski
b48b89f9c1 net: drop the weight argument from netif_napi_add
We tell driver developers to always pass NAPI_POLL_WEIGHT
as the weight to netif_napi_add(). This may be confusing
to newcomers, drop the weight argument, those who really
need to tweak the weight can use netif_napi_add_weight().

Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for CAN
Link: https://lore.kernel.org/r/20220927132753.750069-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 18:57:14 -07:00