Граф коммитов

11174 Коммитов

Автор SHA1 Сообщение Дата
Menglong Dong aeeecb8891 net: snmp: add statistics for tcp small queue check
Once tcp small queue check failed in tcp_small_queue_check(), the
throughput of tcp will be limited, and it's hard to distinguish
whether it is out of tcp congestion control.

Add statistics of LINUX_MIB_TCPSMALLQUEUEFAILURE for this scene.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-29 13:05:47 +00:00
Jakub Kicinski 93d5404e89 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ipa/ipa_main.c
  8afc7e471a ("net: ipa: separate disabling setup from modem stop")
  76b5fbcd6b ("net: ipa: kill ipa_modem_init()")

Duplicated include, drop one.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 13:45:19 -08:00
Eric Dumazet 4e1fddc98d tcp_cubic: fix spurious Hystart ACK train detections for not-cwnd-limited flows
While testing BIG TCP patch series, I was expecting that TCP_RR workloads
with 80KB requests/answers would send one 80KB TSO packet,
then being received as a single GRO packet.

It turns out this was not happening, and the root cause was that
cubic Hystart ACK train was triggering after a few (2 or 3) rounds of RPC.

Hystart was wrongly setting CWND/SSTHRESH to 30, while my RPC
needed a budget of ~20 segments.

Ideally these TCP_RR flows should not exit slow start.

Cubic Hystart should reset itself at each round, instead of assuming
every TCP flow is a bulk one.

Note that even after this patch, Hystart can still trigger, depending
on scheduling artifacts, but at a higher CWND/SSTHRESH threshold,
keeping optimal TSO packet sizes.

Tested:

ip link set dev eth0 gro_ipv6_max_size 131072 gso_ipv6_max_size 131072
nstat -n; netperf -H ... -t TCP_RR  -l 5  -- -r 80000,80000 -K cubic; nstat|egrep "Ip6InReceives|Hystart|Ip6OutRequests"

Before:

   8605
Ip6InReceives                   87541              0.0
Ip6OutRequests                  129496             0.0
TcpExtTCPHystartTrainDetect     1                  0.0
TcpExtTCPHystartTrainCwnd       30                 0.0

After:

  8760
Ip6InReceives                   88514              0.0
Ip6OutRequests                  87975              0.0

Fixes: ae27e98a51 ("[TCP] CUBIC v2.3")
Co-developed-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Link: https://lore.kernel.org/r/20211123202535.1843771-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-24 17:26:05 -08:00
Eric Dumazet 627b94f75b gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers
All gro_complete() handlers are called from napi_gro_complete()
while rcu_read_lock() has been called.

There is no point stacking more rcu_read_lock()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-24 17:21:42 -08:00
Eric Dumazet fc1ca3348a gro: remove rcu_read_lock/rcu_read_unlock from gro_receive handlers
All gro_receive() handlers are called from dev_gro_receive()
while rcu_read_lock() has been called.

There is no point stacking more rcu_read_lock()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-24 17:21:42 -08:00
Kuniyuki Iwashima e7049395b1 dccp/tcp: Remove an unused argument in inet_csk_listen_start().
The commit 1295e2cf30 ("inet: minor optimization for backlog setting in
listen(2)") added change so that sk_max_ack_backlog is initialised earlier
in inet_dccp_listen() and inet_listen().  Since then, we no longer use
backlog in inet_csk_listen_start(), so let's remove it.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Reviewed-by: Richard Sailer <richard_siegfried@systemli.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-23 20:16:18 -08:00
Nikolay Aleksandrov 1c743127cc net: nexthop: fix null pointer dereference when IPv6 is not enabled
When we try to add an IPv6 nexthop and IPv6 is not enabled
(!CONFIG_IPV6) we'll hit a NULL pointer dereference[1] in the error path
of nh_create_ipv6() due to calling ipv6_stub->fib6_nh_release. The bug
has been present since the beginning of IPv6 nexthop gateway support.
Commit 1aefd3de7b ("ipv6: Add fib6_nh_init and release to stubs") tells
us that only fib6_nh_init has a dummy stub because fib6_nh_release should
not be called if fib6_nh_init returns an error, but the commit below added
a call to ipv6_stub->fib6_nh_release in its error path. To fix it return
the dummy stub's -EAFNOSUPPORT error directly without calling
ipv6_stub->fib6_nh_release in nh_create_ipv6()'s error path.

[1]
 Output is a bit truncated, but it clearly shows the error.
 BUG: kernel NULL pointer dereference, address: 000000000000000000
 #PF: supervisor instruction fetch in kernel modede
 #PF: error_code(0x0010) - not-present pagege
 PGD 0 P4D 0
 Oops: 0010 [#1] PREEMPT SMP NOPTI
 CPU: 4 PID: 638 Comm: ip Kdump: loaded Not tainted 5.16.0-rc1+ #446
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014
 RIP: 0010:0x0
 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
 RSP: 0018:ffff888109f5b8f0 EFLAGS: 00010286^Ac
 RAX: 0000000000000000 RBX: ffff888109f5ba28 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881008a2860
 RBP: ffff888109f5b9d8 R08: 0000000000000000 R09: 0000000000000000
 R10: ffff888109f5b978 R11: ffff888109f5b948 R12: 00000000ffffff9f
 R13: ffff8881008a2a80 R14: ffff8881008a2860 R15: ffff8881008a2840
 FS:  00007f98de70f100(0000) GS:ffff88822bf00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffffffffffffd6 CR3: 0000000100efc000 CR4: 00000000000006e0
 Call Trace:
  <TASK>
  nh_create_ipv6+0xed/0x10c
  rtm_new_nexthop+0x6d7/0x13f3
  ? check_preemption_disabled+0x3d/0xf2
  ? lock_is_held_type+0xbe/0xfd
  rtnetlink_rcv_msg+0x23f/0x26a
  ? check_preemption_disabled+0x3d/0xf2
  ? rtnl_calcit.isra.0+0x147/0x147
  netlink_rcv_skb+0x61/0xb2
  netlink_unicast+0x100/0x187
  netlink_sendmsg+0x37f/0x3a0
  ? netlink_unicast+0x187/0x187
  sock_sendmsg_nosec+0x67/0x9b
  ____sys_sendmsg+0x19d/0x1f9
  ? copy_msghdr_from_user+0x4c/0x5e
  ? rcu_read_lock_any_held+0x2a/0x78
  ___sys_sendmsg+0x6c/0x8c
  ? asm_sysvec_apic_timer_interrupt+0x12/0x20
  ? lockdep_hardirqs_on+0xd9/0x102
  ? sockfd_lookup_light+0x69/0x99
  __sys_sendmsg+0x50/0x6e
  do_syscall_64+0xcb/0xf2
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f98dea28914
 Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 48 8d 05 e9 5d 0c 00 8b 00 85 c0 75 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 41 89 d4 55 48 89 f5 53
 RSP: 002b:00007fff859f5e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e2e
 RAX: ffffffffffffffda RBX: 00000000619cb810 RCX: 00007f98dea28914
 RDX: 0000000000000000 RSI: 00007fff859f5ed0 RDI: 0000000000000003
 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000008
 R10: fffffffffffffce6 R11: 0000000000000246 R12: 0000000000000001
 R13: 000055c0097ae520 R14: 000055c0097957fd R15: 00007fff859f63a0
 </TASK>
 Modules linked in: bridge stp llc bonding virtio_net

Cc: stable@vger.kernel.org
Fixes: 53010f991a ("nexthop: Add support for IPv6 gateways")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-23 11:39:53 +00:00
Nikolay Aleksandrov 1005f19b93 net: nexthop: release IPv6 per-cpu dsts when replacing a nexthop group
When replacing a nexthop group, we must release the IPv6 per-cpu dsts of
the removed nexthop entries after an RCU grace period because they
contain references to the nexthop's net device and to the fib6 info.
With specific series of events[1] we can reach net device refcount
imbalance which is unrecoverable. IPv4 is not affected because dsts
don't take a refcount on the route.

[1]
 $ ip nexthop list
  id 200 via 2002:db8::2 dev bridge.10 scope link onlink
  id 201 via 2002:db8::3 dev bridge scope link onlink
  id 203 group 201/200
 $ ip -6 route
  2001:db8::10 nhid 203 metric 1024 pref medium
     nexthop via 2002:db8::3 dev bridge weight 1 onlink
     nexthop via 2002:db8::2 dev bridge.10 weight 1 onlink

Create rt6_info through one of the multipath legs, e.g.:
 $ taskset -a -c 1  ./pkt_inj 24 bridge.10 2001:db8::10
 (pkt_inj is just a custom packet generator, nothing special)

Then remove that leg from the group by replace (let's assume it is id
200 in this case):
 $ ip nexthop replace id 203 group 201

Now remove the IPv6 route:
 $ ip -6 route del 2001:db8::10/128

The route won't be really deleted due to the stale rt6_info holding 1
refcnt in nexthop id 200.
At this point we have the following reference count dependency:
 (deleted) IPv6 route holds 1 reference over nhid 203
 nh 203 holds 1 ref over id 201
 nh 200 holds 1 ref over the net device and the route due to the stale
 rt6_info

Now to create circular dependency between nh 200 and the IPv6 route, and
also to get a reference over nh 200, restore nhid 200 in the group:
 $ ip nexthop replace id 203 group 201/200

And now we have a permanent circular dependncy because nhid 203 holds a
reference over nh 200 and 201, but the route holds a ref over nh 203 and
is deleted.

To trigger the bug just delete the group (nhid 203):
 $ ip nexthop del id 203

It won't really be deleted due to the IPv6 route dependency, and now we
have 2 unlinked and deleted objects that reference each other: the group
and the IPv6 route. Since the group drops the reference it holds over its
entries at free time (i.e. its own refcount needs to drop to 0) that will
never happen and we get a permanent ref on them, since one of the entries
holds a reference over the IPv6 route it will also never be released.

At this point the dependencies are:
 (deleted, only unlinked) IPv6 route holds reference over group nh 203
 (deleted, only unlinked) group nh 203 holds reference over nh 201 and 200
 nh 200 holds 1 ref over the net device and the route due to the stale
 rt6_info

This is the last point where it can be fixed by running traffic through
nh 200, and specifically through the same CPU so the rt6_info (dst) will
get released due to the IPv6 genid, that in turn will free the IPv6
route, which in turn will free the ref count over the group nh 203.

If nh 200 is deleted at this point, it will never be released due to the
ref from the unlinked group 203, it will only be unlinked:
 $ ip nexthop del id 200
 $ ip nexthop
 $

Now we can never release that stale rt6_info, we have IPv6 route with ref
over group nh 203, group nh 203 with ref over nh 200 and 201, nh 200 with
rt6_info (dst) with ref over the net device and the IPv6 route. All of
these objects are only unlinked, and cannot be released, thus they can't
release their ref counts.

 Message from syslogd@dev at Nov 19 14:04:10 ...
  kernel:[73501.828730] unregister_netdevice: waiting for bridge.10 to become free. Usage count = 3
 Message from syslogd@dev at Nov 19 14:04:20 ...
  kernel:[73512.068811] unregister_netdevice: waiting for bridge.10 to become free. Usage count = 3

Fixes: 7bf4796dd0 ("nexthops: add support for replace")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-22 15:44:49 +00:00
Yajun Deng e968b1b3e9 arp: Remove #ifdef CONFIG_PROC_FS
proc_create_net() and remove_proc_entry() already contain the case
whether to define CONFIG_PROC_FS, so remove #ifdef CONFIG_PROC_FS.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-22 14:34:07 +00:00
Poorva Sonparote 4f47d5d507 ipv4: Exposing __ip_sock_set_tos() in ip.h
Making the static function __ip_sock_set_tos() from net/ipv4/ip_sockglue.c
accessible by declaring it in include/net/ip.h
The reason for doing this is to use this function to set IP_TOS value in
mptcp_setsockopt() without the lock.

Signed-off-by: Poorva Sonparote <psonparo@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20 14:11:00 +00:00
Jakub Kicinski 50fc24944a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-18 13:13:16 -08:00
Riccardo Paolo Bestetti 8ff978b8b2 ipv4/raw: support binding to nonlocal addresses
Add support to inet v4 raw sockets for binding to nonlocal addresses
through the IP_FREEBIND and IP_TRANSPARENT socket options, as well as
the ipv4.ip_nonlocal_bind kernel parameter.

Add helper function to inet_sock.h to check for bind address validity on
the base of the address type and whether nonlocal address are enabled
for the socket via any of the sockopts/sysctl, deduplicating checks in
ipv4/ping.c, ipv4/af_inet.c, ipv6/af_inet6.c (for mapped v4->v6
addresses), and ipv4/raw.c.

Add test cases with IP[V6]_FREEBIND verifying that both v4 and v6 raw
sockets support binding to nonlocal addresses after the change. Add
necessary support for the test cases to nettest.

Signed-off-by: Riccardo Paolo Bestetti <pbl@bestov.io>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211117090010.125393-1-pbl@bestov.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-17 20:21:52 -08:00
Eric Dumazet 49ecc2e9c3 net: align static siphash keys
siphash keys use 16 bytes.

Define siphash_aligned_key_t macro so that we can make sure they
are not crossing a cache line boundary.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-16 19:07:54 -08:00
Jakub Kicinski f083ec3160 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-11-16

We've added 12 non-merge commits during the last 5 day(s) which contain
a total of 23 files changed, 573 insertions(+), 73 deletions(-).

The main changes are:

1) Fix pruning regression where verifier went overly conservative rejecting
   previsouly accepted programs, from Alexei Starovoitov and Lorenz Bauer.

2) Fix verifier TOCTOU bug when using read-only map's values as constant
   scalars during verification, from Daniel Borkmann.

3) Fix a crash due to a double free in XSK's buffer pool, from Magnus Karlsson.

4) Fix libbpf regression when cross-building runqslower, from Jean-Philippe Brucker.

5) Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_*() helpers in tracing
   programs due to deadlock possibilities, from Dmitrii Banshchikov.

6) Fix checksum validation in sockmap's udp_read_sock() callback, from Cong Wang.

7) Various BPF sample fixes such as XDP stats in xdp_sample_user, from Alexander Lobakin.

8) Fix libbpf gen_loader error handling wrt fd cleanup, from Kumar Kartikeya Dwivedi.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  udp: Validate checksum in udp_read_sock()
  bpf: Fix toctou on read-only map's constant scalar tracking
  samples/bpf: Fix build error due to -isystem removal
  selftests/bpf: Add tests for restricted helpers
  bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
  libbpf: Perform map fd cleanup for gen_loader in case of error
  samples/bpf: Fix incorrect use of strlen in xdp_redirect_cpu
  tools/runqslower: Fix cross-build
  samples/bpf: Fix summary per-sec stats in xdp_sample_user
  selftests/bpf: Check map in map pruning
  bpf: Fix inner map state pruning regression.
  xsk: Fix crash on double free in buffer pool
====================

Link: https://lore.kernel.org/r/20211116141134.6490-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-16 16:53:48 -08:00
Eric Dumazet b3cb764aa1 net: drop nopreempt requirement on sock_prot_inuse_add()
This is distracting really, let's make this simpler,
because many callers had to take care of this
by themselves, even if on x86 this adds more
code than really needed.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:20:45 +00:00
Eric Dumazet 0b935d7f8c net: gro: move skb_gro_receive_list to udp_offload.c
This helper is used once, no need to keep it in fat net/core/skbuff.c

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:16:54 +00:00
Eric Dumazet 4721031c35 net: move gro definitions to include/net/gro.h
include/linux/netdevice.h became too big, move gro stuff
into include/net/gro.h

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:16:54 +00:00
Eric Dumazet 29fbc26e6d tcp: do not call tcp_cleanup_rbuf() if we have a backlog
Under pressure, tcp recvmsg() has logic to process the socket backlog,
but calls tcp_cleanup_rbuf() right before.

Avoiding sending ACK right before processing new segments makes
a lot of sense, as this decrease the number of ACK packets,
with no impact on effective ACK clocking.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:35 +00:00
Eric Dumazet 8bd172b787 tcp: check local var (timeo) before socket fields in one test
Testing timeo before sk_err/sk_state/sk_shutdown makes more sense.

Modern applications use non-blocking IO, while a socket is terminated
only once during its life time.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:35 +00:00
Eric Dumazet f35f821935 tcp: defer skb freeing after socket lock is released
tcp recvmsg() (or rx zerocopy) spends a fair amount of time
freeing skbs after their payload has been consumed.

A typical ~64KB GRO packet has to release ~45 page
references, eventually going to page allocator
for each of them.

Currently, this freeing is performed while socket lock
is held, meaning that there is a high chance that
BH handler has to queue incoming packets to tcp socket backlog.

This can cause additional latencies, because the user
thread has to process the backlog at release_sock() time,
and while doing so, additional frames can be added
by BH handler.

This patch adds logic to defer these frees after socket
lock is released, or directly from BH handler if possible.

Being able to free these skbs from BH handler helps a lot,
because this avoids the usual alloc/free assymetry,
when BH handler and user thread do not run on same cpu or
NUMA node.

One cpu can now be fully utilized for the kernel->user copy,
and another cpu is handling BH processing and skb/page
allocs/frees (assuming RFS is not forcing use of a single CPU)

Tested:
 100Gbit NIC
 Max throughput for one TCP_STREAM flow, over 10 runs

MTU : 1500
Before: 55 Gbit
After:  66 Gbit

MTU : 4096+(headers)
Before: 82 Gbit
After:  95 Gbit

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:35 +00:00
Eric Dumazet 3df684c1a3 tcp: avoid indirect calls to sock_rfree
TCP uses sk_eat_skb() when skbs can be removed from receive queue.
However, the call to skb_orphan() from __kfree_skb() incurs
an indirect call so sock_rfee(), which is more expensive than
a direct call, especially for CONFIG_RETPOLINE=y.

Add tcp_eat_recv_skb() function to make the call before
__kfree_skb().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:35 +00:00
Eric Dumazet b96c51bd3b tcp: tp->urg_data is unlikely to be set
Use some unlikely() hints in the fast path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet 7b6a893a59 tcp: annotate races around tp->urg_data
tcp_poll() and tcp_ioctl() are reading tp->urg_data without socket lock
owned.

Also, it is faster to first check tp->urg_data in tcp_poll(),
then tp->urg_seq == tp->copied_seq, because tp->urg_seq is
located in a different/cold cache line.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet 0307a0b74b tcp: annotate data-races on tp->segs_in and tp->data_segs_in
tcp_segs_in() can be called from BH, while socket spinlock
is held but socket owned by user, eventually reading these
fields from tcp_get_info()

Found by code inspection, no need to backport this patch
to older kernels.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet 93afcfd1db tcp: small optimization in tcp recvmsg()
When reading large chunks of data, incoming packets might
be added to the backlog from BH.

tcp recvmsg() detects the backlog queue is not empty, and uses
a release_sock()/lock_sock() pair to process this backlog.

We now have __sk_flush_backlog() to perform this
a bit faster.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet 91b6d32563 net: cache align tcp_memory_allocated, tcp_sockets_allocated
tcp_memory_allocated and tcp_sockets_allocated often share
a common cache line, source of false sharing.

Also take care of udp_memory_allocated and mptcp_sockets_allocated.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet aba546565b net: remove sk_route_nocaps
Instead of using a full netdev_features_t, we can use a single bit,
as sk_route_nocaps is only used to remove NETIF_F_GSO_MASK from
sk->sk_route_cap.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet d0d598ca86 net: remove sk_route_forced_caps
We were only using one bit, and we can replace it by sk_is_tcp()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Eric Dumazet d519f35096 tcp: minor optimization in tcp_add_backlog()
If packet is going to be coalesced, sk_sndbuf/sk_rcvbuf values
are not used. Defer their access to the point we need them.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Cong Wang 099f896f49 udp: Validate checksum in udp_read_sock()
It turns out the skb's in sock receive queue could have bad checksums, as
both ->poll() and ->recvmsg() validate checksums. We have to do the same
for ->read_sock() path too before they are redirected in sockmap.

Fixes: d7f571188e ("udp: Implement ->read_sock() for sockmap")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211115044006.26068-1-xiyou.wangcong@gmail.com
2021-11-16 13:18:23 +01:00
Dmitrii Banshchikov 5e0bc3082e bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
Use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in tracing
progs may result in locking issues.

bpf_ktime_get_coarse_ns() uses ktime_get_coarse_ns() time accessor that
isn't safe for any context:
======================================================
WARNING: possible circular locking dependency detected
5.15.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.4/14877 is trying to acquire lock:
ffffffff8cb30008 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255

but task is already holding lock:
ffffffff90dbf200 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x61/0x400 lib/debugobjects.c:735

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&obj_hash[i].lock){-.-.}-{2:2}:
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       __debug_object_init+0xd9/0x1860 lib/debugobjects.c:569
       debug_hrtimer_init kernel/time/hrtimer.c:414 [inline]
       debug_init kernel/time/hrtimer.c:468 [inline]
       hrtimer_init+0x20/0x40 kernel/time/hrtimer.c:1592
       ntp_init_cmos_sync kernel/time/ntp.c:676 [inline]
       ntp_init+0xa1/0xad kernel/time/ntp.c:1095
       timekeeping_init+0x512/0x6bf kernel/time/timekeeping.c:1639
       start_kernel+0x267/0x56e init/main.c:1030
       secondary_startup_64_no_verify+0xb1/0xbb

-> #0 (tk_core.seq.seqcount){----}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add kernel/locking/lockdep.c:3174 [inline]
       validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3789
       __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015
       lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625
       seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103
       ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255
       ktime_get_coarse include/linux/timekeeping.h:120 [inline]
       ktime_get_coarse_ns include/linux/timekeeping.h:126 [inline]
       ____bpf_ktime_get_coarse_ns kernel/bpf/helpers.c:173 [inline]
       bpf_ktime_get_coarse_ns+0x7e/0x130 kernel/bpf/helpers.c:171
       bpf_prog_a99735ebafdda2f1+0x10/0xb50
       bpf_dispatcher_nop_func include/linux/bpf.h:721 [inline]
       __bpf_prog_run include/linux/filter.h:626 [inline]
       bpf_prog_run include/linux/filter.h:633 [inline]
       BPF_PROG_RUN_ARRAY include/linux/bpf.h:1294 [inline]
       trace_call_bpf+0x2cf/0x5d0 kernel/trace/bpf_trace.c:127
       perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9708
       perf_trace_lock+0x37c/0x440 include/trace/events/lock.h:39
       trace_lock_release+0x128/0x150 include/trace/events/lock.h:58
       lock_release+0x82/0x810 kernel/locking/lockdep.c:5636
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
       _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194
       debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
       debug_deactivate kernel/time/hrtimer.c:481 [inline]
       __run_hrtimer kernel/time/hrtimer.c:1653 [inline]
       __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749
       hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
       __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
       sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
       asm_sysvec_apic_timer_interrupt+0x12/0x20
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
       _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
       try_to_wake_up+0x702/0xd20 kernel/sched/core.c:4118
       wake_up_process kernel/sched/core.c:4200 [inline]
       wake_up_q+0x9a/0xf0 kernel/sched/core.c:953
       futex_wake+0x50f/0x5b0 kernel/futex/waitwake.c:184
       do_futex+0x367/0x560 kernel/futex/syscalls.c:127
       __do_sys_futex kernel/futex/syscalls.c:199 [inline]
       __se_sys_futex+0x401/0x4b0 kernel/futex/syscalls.c:180
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

There is a possible deadlock with bpf_timer_* set of helpers:
hrtimer_start()
  lock_base();
  trace_hrtimer...()
    perf_event()
      bpf_run()
        bpf_timer_start()
          hrtimer_start()
            lock_base()         <- DEADLOCK

Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in
BPF_PROG_TYPE_KPROBE, BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT
and BPF_PROG_TYPE_RAW_TRACEPOINT prog types.

Fixes: d055126180 ("bpf: Add bpf_ktime_get_coarse_ns helper")
Fixes: b00628b1c7 ("bpf: Introduce bpf timers.")
Reported-by: syzbot+43fd005b5a1b4d10781e@syzkaller.appspotmail.com
Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-2-me@ubique.spb.ru
2021-11-15 20:35:58 -08:00
Jakub Kicinski a5bdc36354 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-11-15

We've added 72 non-merge commits during the last 13 day(s) which contain
a total of 171 files changed, 2728 insertions(+), 1143 deletions(-).

The main changes are:

1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to
   BTF such that BPF verifier will be able to detect misuse, from Yonghong Song.

2) Big batch of libbpf improvements including various fixes, future proofing APIs,
   and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko.

3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the
   programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush.

4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to
   ensure exception handling still works, from Russell King and Alan Maguire.

5) Add a new bpf_find_vma() helper for tracing to map an address to the backing
   file such as shared library, from Song Liu.

6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump,
   updating documentation and bash-completion among others, from Quentin Monnet.

7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as
   the API is heavily tailored around perf and is non-generic, from Dave Marchevsky.

8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an
   opt-out for more relaxed BPF program requirements, from Stanislav Fomichev.

9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
  bpftool: Use libbpf_get_error() to check error
  bpftool: Fix mixed indentation in documentation
  bpftool: Update the lists of names for maps and prog-attach types
  bpftool: Fix indent in option lists in the documentation
  bpftool: Remove inclusion of utilities.mak from Makefiles
  bpftool: Fix memory leak in prog_dump()
  selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning
  selftests/bpf: Fix an unused-but-set-variable compiler warning
  bpf: Introduce btf_tracing_ids
  bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs
  bpftool: Enable libbpf's strict mode by default
  docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
  selftests/bpf: Clarify llvm dependency with btf_tag selftest
  selftests/bpf: Add a C test for btf_type_tag
  selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c
  selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication
  selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests
  selftests/bpf: Test libbpf API function btf__add_type_tag()
  bpftool: Support BTF_KIND_TYPE_TAG
  libbpf: Support BTF_KIND_TYPE_TAG
  ...
====================

Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-15 08:49:23 -08:00
liuguoqiang 6def480181 net: return correct error code
When kmemdup called failed and register_net_sysctl return NULL, should
return ENOMEM instead of ENOBUFS

Signed-off-by: liuguoqiang <liuguoqiang@uniontech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-15 14:22:12 +00:00
luo penghao 0de3521500 ipv4: Remove duplicate assignments
there is a same action when the variable is initialized

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-14 12:20:44 +00:00
luo penghao ef14102914 ipv4: drop unused assignment
The assignment in the if statement will be overwritten by the
following statement

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-14 12:20:44 +00:00
Arjun Roy 70701b83e2 tcp: Fix uninitialized access in skb frags array for Rx 0cp.
TCP Receive zerocopy iterates through the SKB queue via
tcp_recv_skb(), acquiring a pointer to an SKB and an offset within
that SKB to read from. From there, it iterates the SKB frags array to
determine which offset to start remapping pages from.

However, this is built on the assumption that the offset read so far
within the SKB is smaller than the SKB length. If this assumption is
violated, we can attempt to read an invalid frags array element, which
would cause a fault.

tcp_recv_skb() can cause such an SKB to be returned when the TCP FIN
flag is set. Therefore, we must guard against this occurrence inside
skb_advance_frag().

One way that we can reproduce this error follows:
1) In a receiver program, call getsockopt(TCP_ZEROCOPY_RECEIVE) with:
char some_array[32 * 1024];
struct tcp_zerocopy_receive zc = {
  .copybuf_address  = (__u64) &some_array[0],
  .copybuf_len = 32 * 1024,
};

2) In a sender program, after a TCP handshake, send the following
sequence of packets:
  i) Seq = [X, X+4000]
  ii) Seq = [X+4000, X+5000]
  iii) Seq = [X+4000, X+5000], Flags = FIN | URG, urgptr=1000

(This can happen without URG, if we have a signal pending, but URG is
a convenient way to reproduce the behaviour).

In this case, the following event sequence will occur on the receiver:

tcp_zerocopy_receive():
-> receive_fallback_to_copy() // copybuf_len >= inq
-> tcp_recvmsg_locked() // reads 5000 bytes, then breaks due to URG
-> tcp_recv_skb() // yields skb with skb->len == offset
-> tcp_zerocopy_set_hint_for_skb()
-> skb_advance_to_frag() // will returns a frags ptr. >= nr_frags
-> find_next_mappable_frag() // will dereference this bad frags ptr.

With this patch, skb_advance_to_frag() will no longer return an
invalid frags pointer, and will return NULL instead, fixing the issue.

Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 05255b823a ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Link: https://lore.kernel.org/r/20211111235215.2605384-1-arjunroy.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-12 20:13:28 -08:00
Linus Torvalds f54ca91fe6 Networking fixes for 5.16-rc1, including fixes from bpf, can
and netfilter.
 
 Current release - regressions:
 
  - bpf: do not reject when the stack read size is different
    from the tracked scalar size
 
  - net: fix premature exit from NAPI state polling in napi_disable()
 
  - riscv, bpf: fix RV32 broken build, and silence RV64 warning
 
 Current release - new code bugs:
 
  - net: fix possible NULL deref in sock_reserve_memory
 
  - amt: fix error return code in amt_init(); fix stopping the workqueue
 
  - ax88796c: use the correct ioctl callback
 
 Previous releases - always broken:
 
  - bpf: stop caching subprog index in the bpf_pseudo_func insn
 
  - security: fixups for the security hooks in sctp
 
  - nfc: add necessary privilege flags in netlink layer, limit operations
    to admin only
 
  - vsock: prevent unnecessary refcnt inc for non-blocking connect
 
  - net/smc: fix sk_refcnt underflow on link down and fallback
 
  - nfnetlink_queue: fix OOB when mac header was cleared
 
  - can: j1939: ignore invalid messages per standard
 
  - bpf, sockmap:
    - fix race in ingress receive verdict with redirect to self
    - fix incorrect sk_skb data_end access when src_reg = dst_reg
    - strparser, and tls are reusing qdisc_skb_cb and colliding
 
  - ethtool: fix ethtool msg len calculation for pause stats
 
  - vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries
    to access an unregistering real_dev
 
  - udp6: make encap_rcv() bump the v6 not v4 stats
 
  - drv: prestera: add explicit padding to fix m68k build
 
  - drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge
 
  - drv: mvpp2: fix wrong SerDes reconfiguration order
 
 Misc & small latecomers:
 
  - ipvs: auto-load ipvs on genl access
 
  - mctp: sanity check the struct sockaddr_mctp padding fields
 
  - libfs: support RENAME_EXCHANGE in simple_rename()
 
  - avoid double accounting for pure zerocopy skbs
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf, can and netfilter.

  Current release - regressions:

   - bpf: do not reject when the stack read size is different from the
     tracked scalar size

   - net: fix premature exit from NAPI state polling in napi_disable()

   - riscv, bpf: fix RV32 broken build, and silence RV64 warning

  Current release - new code bugs:

   - net: fix possible NULL deref in sock_reserve_memory

   - amt: fix error return code in amt_init(); fix stopping the
     workqueue

   - ax88796c: use the correct ioctl callback

  Previous releases - always broken:

   - bpf: stop caching subprog index in the bpf_pseudo_func insn

   - security: fixups for the security hooks in sctp

   - nfc: add necessary privilege flags in netlink layer, limit
     operations to admin only

   - vsock: prevent unnecessary refcnt inc for non-blocking connect

   - net/smc: fix sk_refcnt underflow on link down and fallback

   - nfnetlink_queue: fix OOB when mac header was cleared

   - can: j1939: ignore invalid messages per standard

   - bpf, sockmap:
      - fix race in ingress receive verdict with redirect to self
      - fix incorrect sk_skb data_end access when src_reg = dst_reg
      - strparser, and tls are reusing qdisc_skb_cb and colliding

   - ethtool: fix ethtool msg len calculation for pause stats

   - vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries to
     access an unregistering real_dev

   - udp6: make encap_rcv() bump the v6 not v4 stats

   - drv: prestera: add explicit padding to fix m68k build

   - drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge

   - drv: mvpp2: fix wrong SerDes reconfiguration order

  Misc & small latecomers:

   - ipvs: auto-load ipvs on genl access

   - mctp: sanity check the struct sockaddr_mctp padding fields

   - libfs: support RENAME_EXCHANGE in simple_rename()

   - avoid double accounting for pure zerocopy skbs"

* tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (123 commits)
  selftests/net: udpgso_bench_rx: fix port argument
  net: wwan: iosm: fix compilation warning
  cxgb4: fix eeprom len when diagnostics not implemented
  net: fix premature exit from NAPI state polling in napi_disable()
  net/smc: fix sk_refcnt underflow on linkdown and fallback
  net/mlx5: Lag, fix a potential Oops with mlx5_lag_create_definer()
  gve: fix unmatched u64_stats_update_end()
  net: ethernet: lantiq_etop: Fix compilation error
  selftests: forwarding: Fix packet matching in mirroring selftests
  vsock: prevent unnecessary refcnt inc for nonblocking connect
  net: marvell: mvpp2: Fix wrong SerDes reconfiguration order
  net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory
  net: stmmac: allow a tc-taprio base-time of zero
  selftests: net: test_vxlan_under_vrf: fix HV connectivity test
  net: hns3: allow configure ETS bandwidth of all TCs
  net: hns3: remove check VF uc mac exist when set by PF
  net: hns3: fix some mac statistics is always 0 in device version V2
  net: hns3: fix kernel crash when unload VF while it is being reset
  net: hns3: sync rx ring head in echo common pull
  net: hns3: fix pfc packet number incorrect after querying pfc parameters
  ...
2021-11-11 09:49:36 -08:00
Mark Pashmfouroush f89315650b bpf: Add ingress_ifindex to bpf_sk_lookup
It may be helpful to have access to the ifindex during bpf socket
lookup. An example may be to scope certain socket lookup logic to
specific interfaces, i.e. an interface may be made exempt from custom
lookup code.

Add the ifindex of the arriving connection to the bpf_sk_lookup API.

Signed-off-by: Mark Pashmfouroush <markpash@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211110111016.5670-2-markpash@cloudflare.com
2021-11-10 16:29:58 -08:00
John Fastabend c5d2177a72 bpf, sockmap: Fix race in ingress receive verdict with redirect to self
A socket in a sockmap may have different combinations of programs attached
depending on configuration. There can be no programs in which case the socket
acts as a sink only. There can be a TX program in this case a BPF program is
attached to sending side, but no RX program is attached. There can be an RX
program only where sends have no BPF program attached, but receives are hooked
with BPF. And finally, both TX and RX programs may be attached. Giving us the
permutations:

 None, Tx, Rx, and TxRx

To date most of our use cases have been TX case being used as a fast datapath
to directly copy between local application and a userspace proxy. Or Rx cases
and TxRX applications that are operating an in kernel based proxy. The traffic
in the first case where we hook applications into a userspace application looks
like this:

  AppA  redirect   AppB
   Tx <-----------> Rx
   |                |
   +                +
   TCP <--> lo <--> TCP

In this case all traffic from AppA (after 3whs) is copied into the AppB
ingress queue and no traffic is ever on the TCP recieive_queue.

In the second case the application never receives, except in some rare error
cases, traffic on the actual user space socket. Instead the send happens in
the kernel.

           AppProxy       socket pool
       sk0 ------------->{sk1,sk2, skn}
        ^                      |
        |                      |
        |                      v
       ingress              lb egress
       TCP                  TCP

Here because traffic is never read off the socket with userspace recv() APIs
there is only ever one reader on the sk receive_queue. Namely the BPF programs.

However, we've started to introduce a third configuration where the BPF program
on receive should process the data, but then the normal case is to push the
data into the receive queue of AppB.

       AppB
       recv()                (userspace)
     -----------------------
       tcp_bpf_recvmsg()     (kernel)
         |             |
         |             |
         |             |
       ingress_msgQ    |
         |             |
       RX_BPF          |
         |             |
         v             v
       sk->receive_queue

This is different from the App{A,B} redirect because traffic is first received
on the sk->receive_queue.

Now for the issue. The tcp_bpf_recvmsg() handler first checks the ingress_msg
queue for any data handled by the BPF rx program and returned with PASS code
so that it was enqueued on the ingress msg queue. Then if no data exists on
that queue it checks the socket receive queue. Unfortunately, this is the same
receive_queue the BPF program is reading data off of. So we get a race. Its
possible for the recvmsg() hook to pull data off the receive_queue before the
BPF hook has a chance to read it. It typically happens when an application is
banging on recv() and getting EAGAINs. Until they manage to race with the RX
BPF program.

To fix this we note that before this patch at attach time when the socket is
loaded into the map we check if it needs a TX program or just the base set of
proto bpf hooks. Then it uses the above general RX hook regardless of if we
have a BPF program attached at rx or not. This patch now extends this check to
handle all cases enumerated above, TX, RX, TXRX, and none. And to fix above
race when an RX program is attached we use a new hook that is nearly identical
to the old one except now we do not let the recv() call skip the RX BPF program.
Now only the BPF program pulls data from sk->receive_queue and recv() only
pulls data from the ingress msgQ post BPF program handling.

With this resolved our AppB from above has been up and running for many hours
without detecting any errors. We do this by correlating counters in RX BPF
events and the AppB to ensure data is never skipping the BPF program. Selftests,
was not able to detect this because we only run them for a short period of time
on well ordered send/recvs so we don't get any of the noise we see in real
application environments.

Fixes: 51199405f9 ("bpf: skb_verdict, support SK_PASS on RX BPF path")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Jussi Maki <joamaki@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20211103204736.248403-4-john.fastabend@gmail.com
2021-11-09 00:58:26 +01:00
John Fastabend b8b8315e39 bpf, sockmap: Remove unhash handler for BPF sockmap usage
We do not need to handle unhash from BPF side we can simply wait for the
close to happen. The original concern was a socket could transition from
ESTABLISHED state to a new state while the BPF hook was still attached.
But, we convinced ourself this is no longer possible and we also improved
BPF sockmap to handle listen sockets so this is no longer a problem.

More importantly though there are cases where unhash is called when data is
in the receive queue. The BPF unhash logic will flush this data which is
wrong. To be correct it should keep the data in the receive queue and allow
a receiving application to continue reading the data. This may happen when
tcp_abort() is received for example. Instead of complicating the logic in
unhash simply moving all this to tcp_close() hook solves this.

Fixes: 51199405f9 ("bpf: skb_verdict, support SK_PASS on RX BPF path")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Jussi Maki <joamaki@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20211103204736.248403-3-john.fastabend@gmail.com
2021-11-09 00:57:19 +01:00
Linus Torvalds 512b7931ad Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "257 patches.

  Subsystems affected by this patch series: scripts, ocfs2, vfs, and
  mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
  gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
  pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
  memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
  vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
  cleanups, kfence, and damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
  mm/damon: remove return value from before_terminate callback
  mm/damon: fix a few spelling mistakes in comments and a pr_debug message
  mm/damon: simplify stop mechanism
  Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
  Docs/admin-guide/mm/damon/start: simplify the content
  Docs/admin-guide/mm/damon/start: fix a wrong link
  Docs/admin-guide/mm/damon/start: fix wrong example commands
  mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
  mm/damon: remove unnecessary variable initialization
  Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
  mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
  selftests/damon: support watermarks
  mm/damon/dbgfs: support watermarks
  mm/damon/schemes: activate schemes based on a watermarks mechanism
  tools/selftests/damon: update for regions prioritization of schemes
  mm/damon/dbgfs: support prioritization weights
  mm/damon/vaddr,paddr: support pageout prioritization
  mm/damon/schemes: prioritize regions within the quotas
  mm/damon/selftests: support schemes quotas
  mm/damon/dbgfs: support quotas of schemes
  ...
2021-11-06 14:08:17 -07:00
Mianhan Liu a1554c0026 include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h
nr_free_buffer_pages could be exposed through mm.h instead of swap.h.
The advantage of this change is that it can reduce the obsolete
includes.  For example, net/ipv4/tcp.c wouldn't need swap.h any more
since it has already included mm.h.  Similarly, after checking all the
other files, it comes that tcp.c, udp.c meter.c ,...  follow the same
rule, so these files can have swap.h removed too.

Moreover, after preprocessing all the files that use
nr_free_buffer_pages, it turns out that those files have already
included mm.h.Thus, we can move nr_free_buffer_pages from swap.h to mm.h
safely.  This change will not affect the compilation of other files.

Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
CC: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:43 -07:00
Leonard Crestez 3b65abb8d8 tcp: Use BIT() for OPTION_* constants
Extending these flags using the existing (1 << x) pattern triggers
complaints from checkpatch. Instead of ignoring checkpatch modify the
existing values to use BIT(x) style in a separate commit.

Signed-off-by: Leonard Crestez <cdleonard@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-04 11:26:15 +00:00
Talal Ahmad 9b65b17db7 net: avoid double accounting for pure zerocopy skbs
Track skbs containing only zerocopy data and avoid charging them to
kernel memory to correctly account the memory utilization for
msg_zerocopy. All of the data in such skbs is held in user pages which
are already accounted to user. Before this change, they are charged
again in kernel in __zerocopy_sg_from_iter. The charging in kernel is
excessive because data is not being copied into skb frags. This
excessive charging can lead to kernel going into memory pressure
state which impacts all sockets in the system adversely. Mark pure
zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove
charge/uncharge for data in such skbs.

Initially, an skb is marked pure zerocopy when it is empty and in
zerocopy path. skb can then change from a pure zerocopy skb to mixed
data skb (zerocopy and copy data) if it is at tail of write queue and
there is room available in it and non-zerocopy data is being sent in
the next sendmsg call. At this time sk_mem_charge is done for the pure
zerocopied data and the pure zerocopy flag is unmarked. We found that
this happens very rarely on workloads that pass MSG_ZEROCOPY.

A pure zerocopy skb can later be coalesced into normal skb if they are
next to each other in queue but this patch prevents coalescing from
happening. This avoids complexity of charging when skb downgrades from
pure zerocopy to mixed. This is also rare.

In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge
for SKB_TRUESIZE(skb_end_offset(skb)) is done for sk_mem_charge in
tcp_skb_entail for an skb without data.

Testing with the msg_zerocopy.c benchmark between two hosts(100G nics)
with zerocopy showed that before this patch the 'sock' variable in
memory.stat for cgroup2 that tracks sum of sk_forward_alloc,
sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this
change it is 0. This is due to no charge to sk_forward_alloc for
zerocopy data and shows memory utilization for kernel is lowered.

With this commit we don't see the warning we saw in previous commit
which resulted in commit 84882cf72c.

Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-03 11:19:49 +00:00
Eric Dumazet c4777efa75 net: add and use skb_unclone_keeptruesize() helper
While commit 097b9146c0 ("net: fix up truesize of cloned
skb in skb_prepare_for_shift()") fixed immediate issues found
when KFENCE was enabled/tested, there are still similar issues,
when tcp_trim_head() hits KFENCE while the master skb
is cloned.

This happens under heavy networking TX workloads,
when the TX completion might be delayed after incoming ACK.

This patch fixes the WARNING in sk_stream_kill_queues
when sk->sk_mem_queued/sk->sk_forward_alloc are not zero.

Fixes: d3fb45f370 ("mm, kfence: insert KFENCE hooks for SLAB")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20211102004555.1359210-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-02 18:10:34 -07:00
Jakub Kicinski 84882cf72c Revert "net: avoid double accounting for pure zerocopy skbs"
This reverts commit f1a456f8f3.

  WARNING: CPU: 1 PID: 6819 at net/core/skbuff.c:5429 skb_try_coalesce+0x78b/0x7e0
  CPU: 1 PID: 6819 Comm: xxxxxxx Kdump: loaded Tainted: G S                5.15.0-04194-gd852503f7711 #16
  RIP: 0010:skb_try_coalesce+0x78b/0x7e0
  Code: e8 2a bf 41 ff 44 8b b3 bc 00 00 00 48 8b 7c 24 30 e8 19 c0 41 ff 44 89 f0 48 03 83 c0 00 00 00 48 89 44 24 40 e9 47 fb ff ff <0f> 0b e9 ca fc ff ff 4c 8d 70 ff 48 83 c0 07 48 89 44 24 38 e9 61
  RSP: 0018:ffff88881f449688 EFLAGS: 00010282
  RAX: 00000000fffffe96 RBX: ffff8881566e4460 RCX: ffffffff82079f7e
  RDX: 0000000000000003 RSI: dffffc0000000000 RDI: ffff8881566e47b0
  RBP: ffff8881566e46e0 R08: ffffed102619235d R09: ffffed102619235d
  R10: ffff888130c91ae3 R11: ffffed102619235c R12: ffff88881f4498a0
  R13: 0000000000000056 R14: 0000000000000009 R15: ffff888130c91ac0
  FS:  00007fec2cbb9700(0000) GS:ffff88881f440000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fec1b060d80 CR3: 00000003acf94005 CR4: 00000000003706e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <IRQ>
   tcp_try_coalesce+0xeb/0x290
   ? tcp_parse_options+0x610/0x610
   ? mark_held_locks+0x79/0xa0
   tcp_queue_rcv+0x69/0x2f0
   tcp_rcv_established+0xa49/0xd40
   ? tcp_data_queue+0x18a0/0x18a0
   tcp_v6_do_rcv+0x1c9/0x880
   ? rt6_mtu_change_route+0x100/0x100
   tcp_v6_rcv+0x1624/0x1830

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01 22:26:08 -07:00
Jakub Kicinski b7b98f8689 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-11-01

We've added 181 non-merge commits during the last 28 day(s) which contain
a total of 280 files changed, 11791 insertions(+), 5879 deletions(-).

The main changes are:

1) Fix bpf verifier propagation of 64-bit bounds, from Alexei.

2) Parallelize bpf test_progs, from Yucong and Andrii.

3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus.

4) Improve bpf selftests on s390, from Ilya.

5) bloomfilter bpf map type, from Joanne.

6) Big improvements to JIT tests especially on Mips, from Johan.

7) Support kernel module function calls from bpf, from Kumar.

8) Support typeless and weak ksym in light skeleton, from Kumar.

9) Disallow unprivileged bpf by default, from Pawan.

10) BTF_KIND_DECL_TAG support, from Yonghong.

11) Various bpftool cleanups, from Quentin.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits)
  libbpf: Deprecate AF_XDP support
  kbuild: Unify options for BTF generation for vmlinux and modules
  selftests/bpf: Add a testcase for 64-bit bounds propagation issue.
  bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.
  bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off.
  selftests/bpf: Fix also no-alu32 strobemeta selftest
  bpf: Add missing map_delete_elem method to bloom filter map
  selftests/bpf: Add bloom map success test for userspace calls
  bpf: Add alignment padding for "map_extra" + consolidate holes
  bpf: Bloom filter map naming fixups
  selftests/bpf: Add test cases for struct_ops prog
  bpf: Add dummy BPF STRUCT_OPS for test purpose
  bpf: Factor out helpers for ctx access checking
  bpf: Factor out a helper to prepare trampoline for struct_ops prog
  selftests, bpf: Fix broken riscv build
  riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h
  tools, build: Add RISC-V to HOSTARCH parsing
  riscv, bpf: Increase the maximum number of iterations
  selftests, bpf: Add one test for sockmap with strparser
  selftests, bpf: Fix test_txmsg_ingress_parser error
  ...
====================

Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01 19:59:46 -07:00
James Prestwood fcdb44d08a net: arp: introduce arp_evict_nocarrier sysctl parameter
This change introduces a new sysctl parameter, arp_evict_nocarrier.
When set (default) the ARP cache will be cleared on a NOCARRIER event.
This new option has been defaulted to '1' which maintains existing
behavior.

Clearing the ARP cache on NOCARRIER is relatively new, introduced by:

commit 859bd2ef1f
Author: David Ahern <dsahern@gmail.com>
Date:   Thu Oct 11 20:33:49 2018 -0700

    net: Evict neighbor entries on carrier down

The reason for this changes is to prevent the ARP cache from being
cleared when a wireless device roams. Specifically for wireless roams
the ARP cache should not be cleared because the underlying network has not
changed. Clearing the ARP cache in this case can introduce significant
delays sending out packets after a roam.

A user reported such a situation here:

https://lore.kernel.org/linux-wireless/CACsRnHWa47zpx3D1oDq9JYnZWniS8yBwW1h0WAVZ6vrbwL_S0w@mail.gmail.com/

After some investigation it was found that the kernel was holding onto
packets until ARP finished which resulted in this 1 second delay. It
was also found that the first ARP who-has was never responded to,
which is actually what caues the delay. This change is more or less
working around this behavior, but again, there is no reason to clear
the cache on a roam anyways.

As for the unanswered who-has, we know the packet made it OTA since
it was seen while monitoring. Why it never received a response is
unknown. In any case, since this is a problem on the AP side of things
all that can be done is to work around it until it is solved.

Some background on testing/reproducing the packet delay:

Hardware:
 - 2 access points configured for Fast BSS Transition (Though I don't
   see why regular reassociation wouldn't have the same behavior)
 - Wireless station running IWD as supplicant
 - A device on network able to respond to pings (I used one of the APs)

Procedure:
 - Connect to first AP
 - Ping once to establish an ARP entry
 - Start a tcpdump
 - Roam to second AP
 - Wait for operstate UP event, and note the timestamp
 - Start pinging

Results:

Below is the tcpdump after UP. It was recorded the interface went UP at
10:42:01.432875.

10:42:01.461871 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.497976 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.507162 ARP, Reply 192.168.254.1 is-at ac:86:74:55:b0:20, length 46
10:42:02.507185 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 1, length 64
10:42:02.507205 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 2, length 64
10:42:02.507212 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 3, length 64
10:42:02.507219 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 4, length 64
10:42:02.507225 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 5, length 64
10:42:02.507232 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 6, length 64
10:42:02.515373 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 1, length 64
10:42:02.521399 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 2, length 64
10:42:02.521612 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 3, length 64
10:42:02.521941 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 4, length 64
10:42:02.522419 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 5, length 64
10:42:02.523085 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 6, length 64

You can see the first ARP who-has went out very quickly after UP, but
was never responded to. Nearly a second later the kernel retries and
gets a response. Only then do the ping packets go out. If an ARP entry
is manually added prior to UP (after the cache is cleared) it is seen
that the first ping is never responded to, so its not only an issue with
ARP but with data packets in general.

As mentioned prior, the wireless interface was also monitored to verify
the ping/ARP packet made it OTA which was observed to be true.

Signed-off-by: James Prestwood <prestwoj@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01 19:57:14 -07:00
Talal Ahmad f1a456f8f3 net: avoid double accounting for pure zerocopy skbs
Track skbs with only zerocopy data and avoid charging them to kernel
memory to correctly account the memory utilization for msg_zerocopy.
All of the data in such skbs is held in user pages which are already
accounted to user. Before this change, they are charged again in
kernel in __zerocopy_sg_from_iter. The charging in kernel is
excessive because data is not being copied into skb frags. This
excessive charging can lead to kernel going into memory pressure
state which impacts all sockets in the system adversely. Mark pure
zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove
charge/uncharge for data in such skbs.

Initially, an skb is marked pure zerocopy when it is empty and in
zerocopy path. skb can then change from a pure zerocopy skb to mixed
data skb (zerocopy and copy data) if it is at tail of write queue and
there is room available in it and non-zerocopy data is being sent in
the next sendmsg call. At this time sk_mem_charge is done for the pure
zerocopied data and the pure zerocopy flag is unmarked. We found that
this happens very rarely on workloads that pass MSG_ZEROCOPY.

A pure zerocopy skb can later be coalesced into normal skb if they are
next to each other in queue but this patch prevents coalescing from
happening. This avoids complexity of charging when skb downgrades from
pure zerocopy to mixed. This is also rare.

In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge
for SKB_TRUESIZE(MAX_TCP_HEADER) is done for sk_mem_charge in
tcp_skb_entail for an skb without data.

Testing with the msg_zerocopy.c benchmark between two hosts(100G nics)
with zerocopy showed that before this patch the 'sock' variable in
memory.stat for cgroup2 that tracks sum of sk_forward_alloc,
sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this
change it is 0. This is due to no charge to sk_forward_alloc for
zerocopy data and shows memory utilization for kernel is lowered.

Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01 16:33:27 -07:00
Talal Ahmad 03271f3a35 tcp: rename sk_wmem_free_skb
sk_wmem_free_skb() is only used by TCP.

Rename it to make this clear, and move its declaration to
include/net/tcp.h

Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01 16:33:27 -07:00
Hou Tao 35346ab641 bpf: Factor out helpers for ctx access checking
Factor out two helpers to check the read access of ctx for raw tp
and BTF function. bpf_tracing_ctx_access() is used to check
the read access to argument is valid, and bpf_tracing_btf_ctx_access()
checks whether the btf type of argument is valid besides the checking
of argument read. bpf_tracing_btf_ctx_access() will be used by the
following patch.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20211025064025.2567443-3-houtao1@huawei.com
2021-11-01 14:10:00 -07:00
David S. Miller 06f1ecd433 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2021-10-30

Just two minor changes this time:

1) Remove some superfluous header files from xfrm4_tunnel.c
   From Mianhan Liu.

2) Simplify some error checks in xfrm_input().
   From luo penghao.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-01 13:01:44 +00:00
Jakub Kicinski 7df621a3ee Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h
  7b50ecfcc6 ("net: Rename ->stream_memory_read to ->sock_is_readable")
  4c1e34c0db ("vsock: Enable y2038 safe timeval for timeout")

drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
  0daa55d033 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table")
  e77bcdd1f6 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.")

Adjacent code addition in both cases, keep both.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28 10:43:58 -07:00
Maxime Chevallier ee046d9a22 net: ipconfig: Release the rtnl_lock while waiting for carrier
While waiting for a carrier to come on one of the netdevices, some
devices will require to take the rtnl lock at some point to fully
initialize all parts of the link.

That's the case for SFP, where the rtnl is taken when a module gets
detected. This prevents mounting an NFS rootfs over an SFP link.

This means that while ipconfig waits for carriers to be detected, no SFP
modules can be detected in the meantime, it's only detected after
ipconfig times out.

This commit releases the rtnl_lock while waiting for the carrier to come
up, and re-takes it to check the for the init device and carrier status.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 14:36:41 +01:00
Eric Dumazet 8b7d8c2bdb tcp: do not clear TCP_SKB_CB(skb)->sacked if already zero
Freshly allocated skbs have zero in skb->cb[] already.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:39 +01:00
Eric Dumazet 4f2266748e tcp: do not clear skb->csum if already zero
Freshly allocated skbs have their csum field cleared already.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:39 +01:00
Eric Dumazet a52fe46ef1 tcp: factorize ip_summed setting
Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized
in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb()
instead of being done multiple times.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:39 +01:00
Eric Dumazet f401da475f tcp: no longer set skb->reserved_tailroom
TCP/MPTCP sendmsg() no longer puts payload in skb->head,
we can remove not needed code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Eric Dumazet bd44631471 tcp: remove dead code from tcp_collapse_retrans()
TCP sendmsg() no longer puts payload in skb->head,
remove some dead code from tcp_collapse_retrans().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Eric Dumazet 27728ba80f tcp: cleanup tcp_remove_empty_skb() use
All tcp_remove_empty_skb() callers now use tcp_write_queue_tail()
for the skb argument, we can therefore factorize code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Eric Dumazet 3ded97bc41 tcp: remove dead code from tcp_sendmsg_locked()
TCP sendmsg() no longer puts payload in skb head, we can remove
dead code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Paolo Abeni 292e6077b0 net: introduce sk_forward_alloc_get()
A later patch will change the MPTCP memory accounting schema
in such a way that MPTCP sockets will encode the total amount of
forward allocated memory in two separate fields (one for tx and
one for rx).

MPTCP sockets will use their own helper to provide the accurate
amount of fwd allocated memory.

To allow the above, this patch adds a new, optional, sk method to
fetch the fwd memory, wrap the call in a new helper and use it
where it is appropriate.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27 18:20:29 -07:00
Eric Dumazet 9dfc685e02 inet: remove races in inet{6}_getname()
syzbot reported data-races in inet_getname() multiple times,
it is time we fix this instead of pretending applications
should not trigger them.

getsockname() and getpeername() are not really considered fast path.

v2: added the missing BPF_CGROUP_RUN_SA_PROG() declaration
    needed when CONFIG_CGROUP_BPF=n, as reported by
    kernel test robot <lkp@intel.com>

syzbot typical report:

BUG: KCSAN: data-race in __inet_hash_connect / inet_getname

write to 0xffff888136d66cf8 of 2 bytes by task 14374 on cpu 1:
 __inet_hash_connect+0x7ec/0x950 net/ipv4/inet_hashtables.c:831
 inet_hash_connect+0x85/0x90 net/ipv4/inet_hashtables.c:853
 tcp_v4_connect+0x782/0xbb0 net/ipv4/tcp_ipv4.c:275
 __inet_stream_connect+0x156/0x6e0 net/ipv4/af_inet.c:664
 inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:728
 __sys_connect_file net/socket.c:1896 [inline]
 __sys_connect+0x254/0x290 net/socket.c:1913
 __do_sys_connect net/socket.c:1923 [inline]
 __se_sys_connect net/socket.c:1920 [inline]
 __x64_sys_connect+0x3d/0x50 net/socket.c:1920
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888136d66cf8 of 2 bytes by task 14408 on cpu 0:
 inet_getname+0x11f/0x170 net/ipv4/af_inet.c:790
 __sys_getsockname+0x11d/0x1b0 net/socket.c:1946
 __do_sys_getsockname net/socket.c:1961 [inline]
 __se_sys_getsockname net/socket.c:1958 [inline]
 __x64_sys_getsockname+0x3e/0x50 net/socket.c:1958
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000 -> 0xdee0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14408 Comm: syz-executor.3 Not tainted 5.15.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20211026213014.3026708-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27 18:20:21 -07:00
Cong Wang af49338895 net: Implement ->sock_is_readable() for UDP and AF_UNIX
Yucong noticed we can't poll() sockets in sockmap even
when they are the destination sockets of redirections.
This is because we never poll any psock queues in ->poll(),
except for TCP. With ->sock_is_readable() now we can
overwrite >sock_is_readable(), invoke and implement it for
both UDP and AF_UNIX sockets.

Reported-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-4-xiyou.wangcong@gmail.com
2021-10-26 12:29:33 -07:00
Cong Wang fb4e0a5e73 skmsg: Extract and reuse sk_msg_is_readable()
tcp_bpf_sock_is_readable() is pretty much generic,
we can extract it and reuse it for non-TCP sockets.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-3-xiyou.wangcong@gmail.com
2021-10-26 12:29:33 -07:00
Cong Wang 7b50ecfcc6 net: Rename ->stream_memory_read to ->sock_is_readable
The proto ops ->stream_memory_read() is currently only used
by TCP to check whether psock queue is empty or not. We need
to rename it before reusing it for non-TCP protocols, and
adjust the exsiting users accordingly.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-2-xiyou.wangcong@gmail.com
2021-10-26 12:29:33 -07:00
Liu Jian cd9733f5d7 tcp_bpf: Fix one concurrency problem in the tcp_bpf_send_verdict function
With two Msgs, msgA and msgB and a user doing nonblocking sendmsg calls (or
multiple cores) on a single socket 'sk' we could get the following flow.

 msgA, sk                               msgB, sk
 -----------                            ---------------
 tcp_bpf_sendmsg()
 lock(sk)
 psock = sk->psock
                                        tcp_bpf_sendmsg()
                                        lock(sk) ... blocking
tcp_bpf_send_verdict
if (psock->eval == NONE)
   psock->eval = sk_psock_msg_verdict
 ..
 < handle SK_REDIRECT case >
   release_sock(sk)                     < lock dropped so grab here >
   ret = tcp_bpf_sendmsg_redir
                                        psock = sk->psock
                                        tcp_bpf_send_verdict
 lock_sock(sk) ... blocking on B
                                        if (psock->eval == NONE) <- boom.
                                         psock->eval will have msgA state

The problem here is we dropped the lock on msgA and grabbed it with msgB.
Now we have old state in psock and importantly psock->eval has not been
cleared. So msgB will run whatever action was done on A and the verdict
program may never see it.

Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211012052019.184398-1-liujian56@huawei.com
2021-10-26 12:25:55 -07:00
Eric Dumazet c4322884ed tcp: remove unneeded code from tcp_stream_alloc_skb()
Aligning @size argument to 4 bytes is not needed.

The header alignment has nothing to do with @size.

It really depends on skb->head alignment and MAX_TCP_HEADER.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 14:45:12 +01:00
Eric Dumazet 8a794df693 tcp: use MAX_TCP_HEADER in tcp_stream_alloc_skb
Both IPv4 and IPv6 uses same reserve, no need risking
cache line misses to fetch its value.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 14:45:12 +01:00
Eric Dumazet f8dd3b8d70 tcp: rename sk_stream_alloc_skb
sk_stream_alloc_skb() is only used by TCP.

Rename it to make this clear, and move its declaration
to include/net/tcp.h

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 14:45:11 +01:00
Jon Maxwell cf12e6f912 tcp: don't free a FIN sk_buff in tcp_remove_empty_skb()
v1: Implement a more general statement as recommended by Eric Dumazet. The
sequence number will be advanced, so this check will fix the FIN case and
other cases.

A customer reported sockets stuck in the CLOSING state. A Vmcore revealed that
the write_queue was not empty as determined by tcp_write_queue_empty() but the
sk_buff containing the FIN flag had been freed and the socket was zombied in
that state. Corresponding pcaps show no FIN from the Linux kernel on the wire.

Some instrumentation was added to the kernel and it was found that there is a
timing window where tcp_sendmsg() can run after tcp_send_fin().

tcp_sendmsg() will hit an error, for example:

1269 ▹       if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))↩
1270 ▹       ▹       goto do_error;↩

tcp_remove_empty_skb() will then free the FIN sk_buff as "skb->len == 0". The
TCP socket is now wedged in the FIN-WAIT-1 state because the FIN is never sent.

If the other side sends a FIN packet the socket will transition to CLOSING and
remain that way until the system is rebooted.

Fix this by checking for the FIN flag in the sk_buff and don't free it if that
is the case. Testing confirmed that fixed the issue.

Fixes: fdfc5c8594 ("tcp: remove empty skb from write queue in error cases")
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Reported-by: Monir Zouaoui <Monir.Zouaoui@mail.schwarz>
Reported-by: Simon Stier <simon.stier@mail.schwarz>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26 13:10:04 +01:00
Eric Dumazet 020e71a3cf ipv4: guard IP_MINTTL with a static key
RFC 5082 IP_MINTTL option is rarely used on hosts.

Add a static key to remove from TCP fast path useless code,
and potential cache line miss to fetch inet_sk(sk)->min_ttl

Note that once ip4_min_ttl static key has been enabled,
it stays enabled until next boot.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25 18:02:14 -07:00
Eric Dumazet 14834c4f4e ipv4: annotate data races arount inet->min_ttl
No report yet from KCSAN, yet worth documenting the races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25 18:02:13 -07:00
Eric Dumazet 0c0a5ef809 tcp: move inet->rx_dst_ifindex to sk->sk_rx_dst_ifindex
Increase cache locality by moving rx_dst_ifindex next to sk->sk_rx_dst

This is part of an effort to reduce cache line misses in TCP fast path.

This removes one cache line miss in early demux.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-25 18:02:12 -07:00
David S. Miller bdfa75ad70 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Lots of simnple overlapping additions.

With a build fix from Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-22 11:41:16 +01:00
David S. Miller 7adaf56edd Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS for net-next:

1) Add new run_estimation toggle to IPVS to stop the estimation_timer
   logic, from Dust Li.

2) Relax superfluous dynset check on NFT_SET_TIMEOUT.

3) Add egress hook, from Lukas Wunner.

4) Nowadays, almost all hook functions in x_table land just call the hook
   evaluation loop. Remove remaining hook wrappers from iptables and IPVS.
   From Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 14:05:25 +01:00
Leonard Crestez a76c2315be tcp: md5: Allow MD5SIG_FLAG_IFINDEX with ifindex=0
Multiple VRFs are generally meant to be "separate" but right now md5
keys for the default VRF also affect connections inside VRFs if the IP
addresses happen to overlap.

So far the combination of TCP_MD5SIG_FLAG_IFINDEX with tcpm_ifindex == 0
was an error, accept this to mean "key only applies to default VRF".
This is what applications using VRFs for traffic separation want.

Signed-off-by: Leonard Crestez <cdleonard@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 14:36:57 +01:00
Leonard Crestez 86f1e3a848 tcp: md5: Fix overlap between vrf and non-vrf keys
With net.ipv4.tcp_l3mdev_accept=1 it is possible for a listen socket to
accept connection from the same client address in different VRFs. It is
also possible to set different MD5 keys for these clients which differ
only in the tcpm_l3index field.

This appears to work when distinguishing between different VRFs but not
between non-VRF and VRF connections. In particular:

 * tcp_md5_do_lookup_exact will match a non-vrf key against a vrf key.
This means that adding a key with l3index != 0 after a key with l3index
== 0 will cause the earlier key to be deleted. Both keys can be present
if the non-vrf key is added later.
 * _tcp_md5_do_lookup can match a non-vrf key before a vrf key. This
casues failures if the passwords differ.

Fix this by making tcp_md5_do_lookup_exact perform an actual exact
comparison on l3index and by making  __tcp_md5_do_lookup perfer
vrf-bound keys above other considerations like prefixlen.

Fixes: dea53bb80e ("tcp: Add l3index to tcp_md5sig_key and md5 functions")
Signed-off-by: Leonard Crestez <cdleonard@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 14:36:57 +01:00
Eric Dumazet 19757cebf0 tcp: switch orphan_count to bare per-cpu counters
Use of percpu_counter structure to track count of orphaned
sockets is causing problems on modern hosts with 256 cpus
or more.

Stefan Bach reported a serious spinlock contention in real workloads,
that I was able to reproduce with a netfilter rule dropping
incoming FIN packets.

    53.56%  server  [kernel.kallsyms]      [k] queued_spin_lock_slowpath
            |
            ---queued_spin_lock_slowpath
               |
                --53.51%--_raw_spin_lock_irqsave
                          |
                           --53.51%--__percpu_counter_sum
                                     tcp_check_oom
                                     |
                                     |--39.03%--__tcp_close
                                     |          tcp_close
                                     |          inet_release
                                     |          inet6_release
                                     |          sock_close
                                     |          __fput
                                     |          ____fput
                                     |          task_work_run
                                     |          exit_to_usermode_loop
                                     |          do_syscall_64
                                     |          entry_SYSCALL_64_after_hwframe
                                     |          __GI___libc_close
                                     |
                                      --14.48%--tcp_out_of_resources
                                                tcp_write_timeout
                                                tcp_retransmit_timer
                                                tcp_write_timer_handler
                                                tcp_write_timer
                                                call_timer_fn
                                                expire_timers
                                                __run_timers
                                                run_timer_softirq
                                                __softirqentry_text_start

As explained in commit cf86a086a1 ("net/dst: use a smaller percpu_counter
batch for dst entries accounting"), default batch size is too big
for the default value of tcp_max_orphans (262144).

But even if we reduce batch sizes, there would still be cases
where the estimated count of orphans is beyond the limit,
and where tcp_too_many_orphans() has to call the expensive
percpu_counter_sum_positive().

One solution is to use plain per-cpu counters, and have
a timer to periodically refresh this cache.

Updating this cache every 100ms seems about right, tcp pressure
state is not radically changing over shorter periods.

percpu_counter was nice 15 years ago while hosts had less
than 16 cpus, not anymore by current standards.

v2: Fix the build issue for CONFIG_CRYPTO_DEV_CHELSIO_TLS=m,
    reported by kernel test robot <lkp@intel.com>
    Remove unused socket argument from tcp_too_many_orphans()

Fixes: dd24c00191 ("net: Use a percpu_counter for orphan_count")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Stefan Bach <sfb@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 11:28:34 +01:00
Jakub Kicinski e15f5972b8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/ioam6.sh
  7b1700e009 ("selftests: net: modify IOAM tests for undef bits")
  bf77b1400a ("selftests: net: Test for the IOAM encapsulation with IPv6")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 16:50:14 -07:00
Florian Westphal e8d225b600 netfilter: arp_tables: allow use of arpt_do_table as hookfn
This is possible now that the xt_table structure is passed in via *priv.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:06:53 +02:00
Florian Westphal 8844e01062 netfilter: iptables: allow use of ipt_do_table as hookfn
This is possible now that the xt_table structure is passed in via *priv.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:06:53 +02:00
Xin Long 1fcd794518 icmp: fix icmp_ext_echo_iio parsing in icmp_build_probe
In icmp_build_probe(), the icmp_ext_echo_iio parsing should be done
step by step and skb_header_pointer() return value should always be
checked, this patch fixes 3 places in there:

  - On case ICMP_EXT_ECHO_CTYPE_NAME, it should only copy ident.name
    from skb by skb_header_pointer(), its len is ident_len. Besides,
    the return value of skb_header_pointer() should always be checked.

  - On case ICMP_EXT_ECHO_CTYPE_INDEX, move ident_len check ahead of
    skb_header_pointer(), and also do the return value check for
    skb_header_pointer().

  - On case ICMP_EXT_ECHO_CTYPE_ADDR, before accessing iio->ident.addr.
    ctype3_hdr.addrlen, skb_header_pointer() should be called first,
    then check its return value and ident_len.
    On subcases ICMP_AFI_IP and ICMP_AFI_IP6, also do check for ident.
    addr.ctype3_hdr.addrlen and skb_header_pointer()'s return value.
    On subcase ICMP_AFI_IP, the len for skb_header_pointer() should be
    "sizeof(iio->extobj_hdr) + sizeof(iio->ident.addr.ctype3_hdr) +
    sizeof(struct in_addr)" or "ident_len".

v1->v2:
  - To make it more clear, call skb_header_pointer() once only for
    iio->indent's parsing as Jakub Suggested.
v2->v3:
  - The extobj_hdr.length check against sizeof(_iio) should be done
    before calling skb_header_pointer(), as Eric noticed.

Fixes: d329ea5bd8 ("icmp: add response to RFC 8335 PROBE messages")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/31628dd76657ea62f5cf78bb55da6b35240831f1.1634205050.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 07:54:47 -07:00
Jakub Kicinski 5a1b7e1a53 ip: use dev_addr_set() in tunnels
Use dev_addr_set() instead of writing to netdev->dev_addr
directly in ip tunnels drivers.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-13 09:41:37 -07:00
Jakub Kicinski 9fe1155233 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-07 15:24:06 -07:00
Mike Manning 8d6c414cd2 net: prefer socket bound to interface when not in VRF
The commit 6da5b0f027 ("net: ensure unbound datagram socket to be
chosen when not in a VRF") modified compute_score() so that a device
match is always made, not just in the case of an l3mdev skb, then
increments the score also for unbound sockets. This ensures that
sockets bound to an l3mdev are never selected when not in a VRF.
But as unbound and bound sockets are now scored equally, this results
in the last opened socket being selected if there are matches in the
default VRF for an unbound socket and a socket bound to a dev that is
not an l3mdev. However, handling prior to this commit was to always
select the bound socket in this case. Reinstate this handling by
incrementing the score only for bound sockets. The required isolation
due to choosing between an unbound socket and a socket bound to an
l3mdev remains in place due to the device match always being made.
The same approach is taken for compute_score() for stream sockets.

Fixes: 6da5b0f027 ("net: ensure unbound datagram socket to be chosen when not in a VRF")
Fixes: e78190581a ("net: ensure unbound stream socket to be chosen when not in a VRF")
Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/cf0a8523-b362-1edf-ee78-eef63cbbb428@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-07 07:27:55 -07:00
Kumar Kartikeya Dwivedi 0e32dfc80b bpf: Enable TCP congestion control kfunc from modules
This commit moves BTF ID lookup into the newly added registration
helper, in a way that the bbr, cubic, and dctcp implementation set up
their sets in the bpf_tcp_ca kfunc_btf_set list, while the ones not
dependent on modules are looked up from the wrapper function.

This lifts the restriction for them to be compiled as built in objects,
and can be loaded as modules if required. Also modify Makefile.modfinal
to call resolve_btfids for each module.

Note that since kernel kfunc_ids never overlap with module kfunc_ids, we
only match the owner for module btf id sets.

See following commits for background on use of:

 CONFIG_X86 ifdef:
 569c484f99 (bpf: Limit static tcp-cc functions in the .BTF_ids list to x86)

 CONFIG_DYNAMIC_FTRACE ifdef:
 7aae231ac9 (bpf: tcp: Limit calling some tcp cc functions to CONFIG_DYNAMIC_FTRACE)

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211002011757.311265-6-memxor@gmail.com
2021-10-05 17:07:41 -07:00
Kumar Kartikeya Dwivedi 2357672c54 bpf: Introduce BPF support for kernel module function calls
This change adds support on the kernel side to allow for BPF programs to
call kernel module functions. Userspace will prepare an array of module
BTF fds that is passed in during BPF_PROG_LOAD using fd_array parameter.
In the kernel, the module BTFs are placed in the auxilliary struct for
bpf_prog, and loaded as needed.

The verifier then uses insn->off to index into the fd_array. insn->off
0 is reserved for vmlinux BTF (for backwards compat), so userspace must
use an fd_array index > 0 for module kfunc support. kfunc_btf_tab is
sorted based on offset in an array, and each offset corresponds to one
descriptor, with a max limit up to 256 such module BTFs.

We also change existing kfunc_tab to distinguish each element based on
imm, off pair as each such call will now be distinct.

Another change is to check_kfunc_call callback, which now include a
struct module * pointer, this is to be used in later patch such that the
kfunc_id and module pointer are matched for dynamically registered BTF
sets from loadable modules, so that same kfunc_id in two modules doesn't
lead to check_kfunc_call succeeding. For the duration of the
check_kfunc_call, the reference to struct module exists, as it returns
the pointer stored in kfunc_btf_tab.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211002011757.311265-2-memxor@gmail.com
2021-10-05 17:07:41 -07:00
David S. Miller dade7f9d81 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net (v2)

The following patchset contains Netfilter fixes for net:

1) Move back the defrag users fields to the global netns_nf area.
   Kernel fails to boot if conntrack is builtin and kernel is booted
   with: nf_conntrack.enable_hooks=1. From Florian Westphal.

2) Rule event notification is missing relevant context such as
   the position handle and the NLM_F_APPEND flag.

3) Rule replacement is expanded to add + delete using the existing
   rule handle, reverse order of this operation so it makes sense
   from rule notification standpoint.

4) Propagate to userspace the NLM_F_CREATE and NLM_F_EXCL flags
   from the rule notification path.

Patches #2, #3 and #4 are used by 'nft monitor' and 'iptables-monitor'
userspace utilities which are not correctly representing the following
operations through netlink notifications:

- rule insertions
- rule addition/insertion from position handle
- create table/chain/set/map/flowtable/...
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-02 13:55:02 +01:00
Jakub Kicinski dd9a887b35 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/phy/bcm7xxx.c
  d88fd1b546 ("net: phy: bcm7xxx: Fixed indirect MMD operations")
  f68d08c437 ("net: phy: bcm7xxx: Add EPHY entry for 72165")

net/sched/sch_api.c
  b193e15ac6 ("net: prevent user from passing illegal stab size")
  69508d4333 ("net_sched: Use struct_size() and flex_array_size() helpers")

Both cases trivial - adjacent code additions.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30 14:49:21 -07:00
Eric Dumazet 59f09ae8fa net: snmp: inline snmp_get_cpu_field()
This trivial function is called ~90,000 times on 256 cpus hosts,
when reading /proc/net/netstat. And this number keeps inflating.

Inlining it saves many cycles.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 14:17:10 +01:00
Wei Wang 053f368412 tcp: adjust rcv_ssthresh according to sk_reserved_mem
When user sets SO_RESERVE_MEM socket option, in order to utilize the
reserved memory when in memory pressure state, we adjust rcv_ssthresh
according to the available reserved memory for the socket, instead of
using 4 * advmss always.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:36:46 +01:00
Wei Wang ca057051cf tcp: adjust sndbuf according to sk_reserved_mem
If user sets SO_RESERVE_MEM socket option, in order to fully utilize the
reserved memory in memory pressure state on the tx path, we modify the
logic in sk_stream_moderate_sndbuf() to set sk_sndbuf according to
available reserved memory, instead of MIN_SOCK_SNDBUF, and adjust it
when new data is acked.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:36:46 +01:00
Wei Wang 2bb2f5fb21 net: add new socket option SO_RESERVE_MEM
This socket option provides a mechanism for users to reserve a certain
amount of memory for the socket to use. When this option is set, kernel
charges the user specified amount of memory to memcg, as well as
sk_forward_alloc. This amount of memory is not reclaimable and is
available in sk_forward_alloc for this socket.
With this socket option set, the networking stack spends less cycles
doing forward alloc and reclaim, which should lead to better system
performance, with the cost of an amount of pre-allocated and
unreclaimable memory, even under memory pressure.

Note:
This socket option is only available when memory cgroup is enabled and we
require this reserved memory to be charged to the user's memcg. We hope
this could avoid mis-behaving users to abused this feature to reserve a
large amount on certain sockets and cause unfairness for others.

Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:36:46 +01:00
Mianhan Liu 6a832a6c72 net/ipv4/datagram.c: remove superfluous header files from datagram.c
datagram.c hasn't use any macro or function declared in linux/ip.h.
Thus, these files can be removed from datagram.c safely without
affecting the compilation of the net/ipv4 module

Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-29 11:39:33 +01:00
Mianhan Liu 3d5f12d4ff net: ipv4: remove superfluous header files from fib_notifier.c
fib_notifier.c hasn't use any macro or function declared
in net/netns/ipv4.h.

Thus, these files can be removed from fib_notifier.c safely
without affecting the compilation of the net/ipv4 module.

Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Link: https://lore.kernel.org/r/20210928164011.1454-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-28 17:32:56 -07:00
Eric Dumazet a9f5970767 net: udp: annotate data race around udp_sk(sk)->corkflag
up->corkflag field can be read or written without any lock.
Annotate accesses to avoid possible syzbot/KCSAN reports.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-28 13:21:16 +01:00
Florian Westphal 339031bafe netfilter: conntrack: fix boot failure with nf_conntrack.enable_hooks=1
This is a revert of
7b1957b049 ("netfilter: nf_defrag_ipv4: use net_generic infra")
and a partial revert of
8b0adbe3e3 ("netfilter: nf_defrag_ipv6: use net_generic infra").

If conntrack is builtin and kernel is booted with:
nf_conntrack.enable_hooks=1

.... kernel will fail to boot due to a NULL deref in
nf_defrag_ipv4_enable(): Its called before the ipv4 defrag initcall is
made, so net_generic() returns NULL.

To resolve this, move the user refcount back to struct net so calls
to those functions are possible even before their initcalls have run.

Fixes: 7b1957b049 ("netfilter: nf_defrag_ipv4: use net_generic infra")
Fixes: 8b0adbe3e3 ("netfilter: nf_defrag_ipv6: use net_generic infra").
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-28 13:04:55 +02:00
Mianhan Liu 2b73e209ba net/ipv4/tcp_nv.c: remove superfluous header files from tcp_nv.c
tcp_nv.c hasn't use any macro or function declared in mm.h. Thus, these files
can be removed from tcp_nv.c safely without affecting the compilation
of the net module.

Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-27 12:47:39 +01:00
Jakub Kicinski 7fe7f3182a Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

1) ipset limits the max allocatable memory via kvmalloc() to MAX_INT,
   from Jozsef Kadlecsik.

2) Check ip_vs_conn_tab_bits value to be in the range specified
   in Kconfig, from Andrea Claudi.

3) Initialize fragment offset in ip6tables, from Jeremy Sowden.

4) Make conntrack hash chain length random, from Florian Westphal.

5) Add zone ID to conntrack and NAT hashtuple again, also from Florian.

6) Add selftests for bidirectional zone support and colliding tuples,
   from Florian Westphal.

7) Unlink table before synchronize_rcu when cleaning tables with
   owner, from Florian.

8) ipset limits the max allocatable memory via kvmalloc() to MAX_INT.

9) Release conntrack entries via workqueue in masquerade, from Florian.

10) Fix bogus net_init in iptables raw table definition, also from Florian.

11) Work around missing softdep in log extensions, from Florian Westphal.

12) Serialize hash resizes and cleanups with mutex, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf:
  netfilter: conntrack: serialize hash resizes and cleanups
  netfilter: log: work around missing softdep backend module
  netfilter: iptable_raw: drop bogus net_init annotation
  netfilter: nf_nat_masquerade: defer conntrack walk to work queue
  netfilter: nf_nat_masquerade: make async masq_inet6_event handling generic
  netfilter: nf_tables: Fix oversized kvmalloc() calls
  netfilter: nf_tables: unlink table before deleting it
  selftests: netfilter: add zone stress test with colliding tuples
  selftests: netfilter: add selftest for directional zone support
  netfilter: nat: include zone id in nat table hash again
  netfilter: conntrack: include zone id in tuple hash again
  netfilter: conntrack: make max chain length random
  netfilter: ip6_tables: zero-initialize fragment offset
  ipvs: check that ip_vs_conn_tab_bits is between 8 and 20
  netfilter: ipset: Fix oversized kvmalloc() calls
====================

Link: https://lore.kernel.org/r/20210924221113.348767-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-24 17:27:20 -07:00