This reverts the following patches :

- commit 2e05fcae ("tcp: fix compile error if !CONFIG_SYSCTL")
- commit 4f661542 ("tcp: fix zerocopy and notsent_lowat issues")
- commit 472c2e07 ("tcp: add one skb cache for tx")
- commit 8b27dae5 ("tcp: add one skb cache for rx")

Having a cache of one skb (in each direction) per TCP socket is fragile,
since it can cause a significant increase of memory needs,
and not good enough for high speed flows anyway where more than one skb
is needed.

We want instead to add a generic infrastructure, with more flexible
per-cpu caches, for alien NUMA nodes.
Acked-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add an enum (cgroup_bpf_attach_type) containing only valid cgroup_bpf
attach types and a function to map bpf_attach_type values to the new
enum. Inspired by netns_bpf_attach_type.

Then, migrate cgroup_bpf to use cgroup_bpf_attach_type wherever
possible.  Functionality is unchanged as attach_type_to_prog_type
switches in bpf/syscall.c were preventing non-cgroup programs from
making use of the invalid cgroup_bpf array slots.

As a result struct cgroup_bpf uses 504 fewer bytes relative to when its
arrays were sized using MAX_BPF_ATTACH_TYPE.

bpf_cgroup_storage is notably not migrated as struct
bpf_cgroup_storage_key is part of uapi and contains a bpf_attach_type
member which is not meant to be opaque. Similarly, bpf_cgroup_link
continues to report its bpf_attach_type member to userspace via fdinfo
and bpf_link_info.

To ease disambiguation, bpf_attach_type variables are renamed from
'type' to 'atype' when changed to cgroup_bpf_attach_type.
Signed-off-by: NDave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210819092420.1984861-2-davemarchevsky@fb.com

compat_ifreq_ioctl() is one of the last users of copy_in_user() and
compat_alloc_user_space(), as it attempts to convert the 'struct ifreq'
arguments from 32-bit to 64-bit format as used by dev_ioctl() and a
couple of socket family specific interpretations.

The current implementation works correctly when calling dev_ioctl(),
inet_ioctl(), ieee802154_sock_ioctl(), atalk_ioctl(), qrtr_ioctl()
and packet_ioctl(). The ioctl handlers for x25, netrom, rose and x25 do
not interpret the arguments and only block the corresponding commands,
so they do not care.

For af_inet6 and af_decnet however, the compat conversion is slightly
incorrect, as it will copy more data than the native handler accesses,
both of them use a structure that is shorter than ifreq.

Replace the copy_in_user() conversion with a pair of accessor functions
to read and write the ifreq data in place with the correct length where
needed, while leaving the other ones to copy the (already compatible)
structures directly.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both functions are known to be racy when reading inet_num
as we do not want to grab locks for the common case the socket
has been bound already. The race is resolved in inet_autobind()
by reading again inet_num under the socket lock.

syzbot reported:
BUG: KCSAN: data-race in inet_send_prepare / udp_lib_get_port

write to 0xffff88812cba150e of 2 bytes by task 24135 on cpu 0:
 udp_lib_get_port+0x4b2/0xe20 net/ipv4/udp.c:308
 udp_v6_get_port+0x5e/0x70 net/ipv6/udp.c:89
 inet_autobind net/ipv4/af_inet.c:183 [inline]
 inet_send_prepare+0xd0/0x210 net/ipv4/af_inet.c:807
 inet6_sendmsg+0x29/0x80 net/ipv6/af_inet6.c:639
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2490
 __do_sys_sendmmsg net/socket.c:2519 [inline]
 __se_sys_sendmmsg net/socket.c:2516 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2516
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812cba150e of 2 bytes by task 24132 on cpu 1:
 inet_send_prepare+0x21/0x210 net/ipv4/af_inet.c:806
 inet6_sendmsg+0x29/0x80 net/ipv6/af_inet6.c:639
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2490
 __do_sys_sendmmsg net/socket.c:2519 [inline]
 __se_sys_sendmmsg net/socket.c:2516 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2516
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000 -> 0x9db4

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24132 Comm: syz-executor.2 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.
Signed-off-by: NZheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Every protocol has the 'netns_ok' member and it is euqal to 1. The
'if (!prot->netns_ok)' always false in inet_add_protocol().
Signed-off-by: NYejune Deng <yejunedeng@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is similar to tcp_read_sock(), except we do not need
to worry about connections, we just need to retrieve skb
from UDP receive queue.

Note, the return value of ->read_sock() is unused in
sk_psock_verdict_data_ready(), and UDP still does not
support splice() due to lack of ->splice_read(), so users
can not reach udp_read_sock() directly.
Signed-off-by: NCong Wang <cong.wang@bytedance.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210331023237.41094-12-xiyou.wangcong@gmail.com

No need to restrict these anymore, as the worker threads are direct
clones of the original task. Hence we know for a fact that we can
support anything that the regular task can.

Since the only user of proto_ops->flags was to flag PROTO_CMSG_DATA_ONLY,
kill the member and the flag definition too.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

inet_gro_receive() and inet_gro_complete() are part
of GRO engine which can not be modular.

Similarly, inet_gso_segment() does not need to be exported,
being part of GSO stack.

In other words, net/ipv6/ip6_offload.o is part of vmlinux,
regardless of CONFIG_IPV6.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20210202154145.1568451-1-eric.dumazet@gmail.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

After installing a route to the kernel, user space receives an
acknowledgment, which means the route was installed in the kernel,
but not necessarily in hardware.

The asynchronous nature of route installation in hardware can lead to a
routing daemon advertising a route before it was actually installed in
hardware. This can result in packet loss or mis-routed packets until the
route is installed in hardware.

It is also possible for a route already installed in hardware to change
its action and therefore its flags. For example, a host route that is
trapping packets can be "promoted" to perform decapsulation following
the installation of an IPinIP/VXLAN tunnel.

Emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags
are changed. The aim is to provide an indication to user-space
(e.g., routing daemons) about the state of the route in hardware.

Introduce a sysctl that controls this behavior.

Keep the default value at 0 (i.e., do not emit notifications) for several
reasons:
- Multiple RTM_NEWROUTE notification per-route might confuse existing
  routing daemons.
- Convergence reasons in routing daemons.
- The extra notifications will negatively impact the insertion rate.
- Not all users are interested in these notifications.
Signed-off-by: NAmit Cohen <amcohen@nvidia.com>
Acked-by: NRoopa Prabhu <roopa@nvidia.com>
Signed-off-by: NIdo Schimmel <idosch@nvidia.com>
Reviewed-by: NDavid Ahern <dsahern@kernel.org>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

At the moment, BPF_CGROUP_INET{4,6}_BIND hooks can rewrite user_port
to the privileged ones (< ip_unprivileged_port_start), but it will
be rejected later on in the __inet_bind or __inet6_bind.

Let's add another return value to indicate that CAP_NET_BIND_SERVICE
check should be ignored. Use the same idea as we currently use
in cgroup/egress where bit #1 indicates CN. Instead, for
cgroup/bind{4,6}, bit #1 indicates that CAP_NET_BIND_SERVICE should
be bypassed.

v5:
- rename flags to be less confusing (Andrey Ignatov)
- rework BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY to work on flags
  and accept BPF_RET_SET_CN (no behavioral changes)

v4:
- Add missing IPv6 support (Martin KaFai Lau)

v3:
- Update description (Martin KaFai Lau)
- Fix capability restore in selftest (Martin KaFai Lau)

v2:
- Switch to explicit return code (Martin KaFai Lau)
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Reviewed-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/20210127193140.3170382-1-sdf@google.com

When we attach any cgroup hook, the rest (even if unused/unattached) start
to contribute small overhead. In particular, the one we want to avoid is
__cgroup_bpf_run_filter_skb which does two redirections to get to
the cgroup and pushes/pulls skb.

Let's split cgroup_bpf_enabled to be per-attach to make sure
only used attach types trigger.

I've dropped some existing high-level cgroup_bpf_enabled in some
places because BPF_PROG_CGROUP_XXX_RUN macros usually have another
cgroup_bpf_enabled check.

I also had to copy-paste BPF_CGROUP_RUN_SA_PROG_LOCK for
GETPEERNAME/GETSOCKNAME because type for cgroup_bpf_enabled[type]
has to be constant and known at compile time.
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210115163501.805133-4-sdf@google.com

I have to now lock/unlock socket for the bind hook execution.
That shouldn't cause any overhead because the socket is unbound
and shouldn't receive any traffic.
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/20201202172516.3483656-3-sdf@google.com

For TCP tx zero-copy, the kernel notifies the process of completions by
queuing completion notifications on the socket error queue. This patch
allows reading these notifications via recvmsg to support TCP tx
zero-copy.

Ancillary data was originally disallowed due to privilege escalation
via io_uring's offloading of sendmsg() onto a kernel thread with kernel
credentials (https://crbug.com/project-zero/1975). So, we must ensure
that the socket type is one where the ancillary data types that are
delivered on recvmsg are plain data (no file descriptors or values that
are translated based on the identity of the calling process).

This was tested by using io_uring to call recvmsg on the MSG_ERRQUEUE
with tx zero-copy enabled. Before this patch, we received -EINVALID from
this specific code path. After this patch, we could read tcp tx
zero-copy completion notifications from the MSG_ERRQUEUE.
Signed-off-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NArjun Roy <arjunroy@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Reviewed-by: NJann Horn <jannh@google.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NLuke Hsiao <lukehsiao@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the compat handling to sock_common_{get,set}sockopt instead,
keyed of in_compat_syscall().  This allow to remove the now unused
->compat_{get,set}sockopt methods from struct proto_ops.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NMatthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: NStefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sometimes it's handy to know when the socket gets freed. In
particular, we'd like to try to use a smarter allocation of
ports for bpf_bind and explore the possibility of limiting
the number of SOCK_DGRAM sockets the process can have.

Implement BPF_CGROUP_INET_SOCK_RELEASE hook that triggers on
inet socket release. It triggers only for userspace sockets
(not in-kernel ones) and therefore has the same semantics as
the existing BPF_CGROUP_INET_SOCK_CREATE.
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200706230128.4073544-2-sdf@google.com

This removes following warnings :
  CC      net/ipv4/udp_offload.o
net/ipv4/udp_offload.c:504:17: warning: no previous prototype for 'udp4_gro_receive' [-Wmissing-prototypes]
  504 | struct sk_buff *udp4_gro_receive(struct list_head *head, struct sk_buff *skb)
      |                 ^~~~~~~~~~~~~~~~
net/ipv4/udp_offload.c:584:29: warning: no previous prototype for 'udp4_gro_complete' [-Wmissing-prototypes]
  584 | INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff)
      |                             ^~~~~~~~~~~~~~~~~

  CHECK   net/ipv6/udp_offload.c
net/ipv6/udp_offload.c:115:16: warning: symbol 'udp6_gro_receive' was not declared. Should it be static?
net/ipv6/udp_offload.c:148:29: warning: symbol 'udp6_gro_complete' was not declared. Should it be static?
  CC      net/ipv6/udp_offload.o
net/ipv6/udp_offload.c:115:17: warning: no previous prototype for 'udp6_gro_receive' [-Wmissing-prototypes]
  115 | struct sk_buff *udp6_gro_receive(struct list_head *head, struct sk_buff *skb)
      |                 ^~~~~~~~~~~~~~~~
net/ipv6/udp_offload.c:148:29: warning: no previous prototype for 'udp6_gro_complete' [-Wmissing-prototypes]
  148 | INDIRECT_CALLABLE_SCOPE int udp6_gro_complete(struct sk_buff *skb, int nhoff)
      |                             ^~~~~~~~~~~~~~~~~
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes following (C=1 W=1) warnings for CONFIG_RETPOLINE=y :

net/ipv4/tcp_offload.c:306:16: warning: symbol 'tcp4_gro_receive' was not declared. Should it be static?
net/ipv4/tcp_offload.c:306:17: warning: no previous prototype for 'tcp4_gro_receive' [-Wmissing-prototypes]
net/ipv4/tcp_offload.c:319:29: warning: symbol 'tcp4_gro_complete' was not declared. Should it be static?
net/ipv4/tcp_offload.c:319:29: warning: no previous prototype for 'tcp4_gro_complete' [-Wmissing-prototypes]
  CHECK   net/ipv6/tcpv6_offload.c
net/ipv6/tcpv6_offload.c:16:16: warning: symbol 'tcp6_gro_receive' was not declared. Should it be static?
net/ipv6/tcpv6_offload.c:29:29: warning: symbol 'tcp6_gro_complete' was not declared. Should it be static?
  CC      net/ipv6/tcpv6_offload.o
net/ipv6/tcpv6_offload.c:16:17: warning: no previous prototype for 'tcp6_gro_receive' [-Wmissing-prototypes]
   16 | struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb)
      |                 ^~~~~~~~~~~~~~~~
net/ipv6/tcpv6_offload.c:29:29: warning: no previous prototype for 'tcp6_gro_complete' [-Wmissing-prototypes]
   29 | INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff)
      |                             ^~~~~~~~~~~~~~~~~
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As stated in 983695fa ("bpf: fix unconnected udp hooks"), the objective
for the existing cgroup connect/sendmsg/recvmsg/bind BPF hooks is to be
transparent to applications. In Cilium we make use of these hooks [0] in
order to enable E-W load balancing for existing Kubernetes service types
for all Cilium managed nodes in the cluster. Those backends can be local
or remote. The main advantage of this approach is that it operates as close
as possible to the socket, and therefore allows to avoid packet-based NAT
given in connect/sendmsg/recvmsg hooks we only need to xlate sock addresses.

This also allows to expose NodePort services on loopback addresses in the
host namespace, for example. As another advantage, this also efficiently
blocks bind requests for applications in the host namespace for exposed
ports. However, one missing item is that we also need to perform reverse
xlation for inet{,6}_getname() hooks such that we can return the service
IP/port tuple back to the application instead of the remote peer address.

The vast majority of applications does not bother about getpeername(), but
in a few occasions we've seen breakage when validating the peer's address
since it returns unexpectedly the backend tuple instead of the service one.
Therefore, this trivial patch allows to customise and adds a getpeername()
as well as getsockname() BPF cgroup hook for both IPv4 and IPv6 in order
to address this situation.

Simple example:

  # ./cilium/cilium service list
  ID   Frontend     Service Type   Backend
  1    1.2.3.4:80   ClusterIP      1 => 10.0.0.10:80

Before; curl's verbose output example, no getpeername() reverse xlation:

  # curl --verbose 1.2.3.4
  * Rebuilt URL to: 1.2.3.4/
  *   Trying 1.2.3.4...
  * TCP_NODELAY set
  * Connected to 1.2.3.4 (10.0.0.10) port 80 (#0)
  > GET / HTTP/1.1
  > Host: 1.2.3.4
  > User-Agent: curl/7.58.0
  > Accept: */*
  [...]

After; with getpeername() reverse xlation:

  # curl --verbose 1.2.3.4
  * Rebuilt URL to: 1.2.3.4/
  *   Trying 1.2.3.4...
  * TCP_NODELAY set
  * Connected to 1.2.3.4 (1.2.3.4) port 80 (#0)
  > GET / HTTP/1.1
  >  Host: 1.2.3.4
  > User-Agent: curl/7.58.0
  > Accept: */*
  [...]

Originally, I had both under a BPF_CGROUP_INET{4,6}_GETNAME type and exposed
peer to the context similar as in inet{,6}_getname() fashion, but API-wise
this is suboptimal as it always enforces programs having to test for ctx->peer
which can easily be missed, hence BPF_CGROUP_INET{4,6}_GET{PEER,SOCK}NAME split.
Similarly, the checked return code is on tnum_range(1, 1), but if a use case
comes up in future, it can easily be changed to return an error code instead.
Helper and ctx member access is the same as with connect/sendmsg/etc hooks.

  [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.cSigned-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/61a479d759b2482ae3efb45546490bacd796a220.1589841594.git.daniel@iogearbox.net

To prepare removing the global routing_ioctl hack start lifting the code
into the ipv4 and appletalk ->compat_ioctl handlers.  Unlike the existing
handler we don't bother copying in the name - there are no compat issues for
char arrays.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We want to have a tighter control on what ports we bind to in
the BPF_CGROUP_INET{4,6}_CONNECT hooks even if it means
connect() becomes slightly more expensive. The expensive part
comes from the fact that we now need to call inet_csk_get_port()
that verifies that the port is not used and allocates an entry
in the hash table for it.

Since we can't rely on "snum || !bind_address_no_port" to prevent
us from calling POST_BIND hook anymore, let's add another bind flag
to indicate that the call site is BPF program.

v5:
* fix wrong AF_INET (should be AF_INET6) in the bpf program for v6

v3:
* More bpf_bind documentation refinements (Martin KaFai Lau)
* Add UDP tests as well (Martin KaFai Lau)
* Don't start the thread, just do socket+bind+listen (Martin KaFai Lau)

v2:
* Update documentation (Andrey Ignatov)
* Pass BIND_FORCE_ADDRESS_NO_PORT conditionally (Andrey Ignatov)
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200508174611.228805-5-sdf@google.com

The intent is to add an additional bind parameter in the next commit.
Instead of adding another argument, let's convert all existing
flag arguments into an extendable bit field.

No functional changes.
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrey Ignatov <rdna@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200508174611.228805-4-sdf@google.com

Current route nexthop API maintains user space compatibility
with old route API by default. Dumps and netlink notifications
support both new and old API format. In systems which have
moved to the new API, this compatibility mode cancels some
of the performance benefits provided by the new nexthop API.

This patch adds new sysctl nexthop_compat_mode which is on
by default but provides the ability to turn off compatibility
mode allowing systems to run entirely with the new routing
API. Old route API behaviour and support is not modified by this
sysctl.

Uses a single sysctl to cover both ipv4 and ipv6 following
other sysctls. Covers dumps and delete notifications as
suggested by David Ahern.
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The variable rc is being assigned with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Exported via same /proc file as the Linux TCP MIB counters, so "netstat -s"
or "nstat" will show them automatically.

The MPTCP MIB counters are allocated in a distinct pcpu area in order to
avoid bloating/wasting TCP pcpu memory.

Counters are allocated once the first MPTCP socket is created in a
network namespace and free'd on exit.

If no sockets have been allocated, all-zero mptcp counters are shown.

The MIB counter list is taken from the multipath-tcp.org kernel, but
only a few counters have been picked up so far.  The counter list can
be increased at any time later on.

v2 -> v3:
 - remove 'inline' in foo.c files (David S. Miller)
Co-developed-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert the various uses of fallthrough comments to fallthrough;

Done via script
Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/

And by hand:

net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block
that causes gcc to emit a warning if converted in-place.

So move the new fallthrough; inside the containing #ifdef/#endif too.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Note that the sysctl write accessor functions guarantee that:
  net->ipv4.sysctl_ip_prot_sock <= net->ipv4.ip_local_ports.range[0]
invariant is maintained, and as such the max() in selinux hooks is actually spurious.

ie. even though
  if (snum < max(inet_prot_sock(sock_net(sk)), low) || snum > high) {
per logic is the same as
  if ((snum < inet_prot_sock(sock_net(sk)) && snum < low) || snum > high) {
it is actually functionally equivalent to:
  if (snum < low || snum > high) {
which is equivalent to:
  if (snum < inet_prot_sock(sock_net(sk)) || snum < low || snum > high) {
even though the first clause is spurious.

But we want to hold on to it in case we ever want to change what what
inet_port_requires_bind_service() means (for example by changing
it from a, by default, [0..1024) range to some sort of set).

Test: builds, git 'grep inet_prot_sock' finds no other references
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_max_ack_backlog can be read without any lock being held
at least in TCP/DCCP cases.

We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pointer members of an object with static storage duration, if not
explicitly initialized, will be initialized to a NULL pointer. The
net namespace API checks if this pointer is not NULL before using it,
it are safe to remove the function.
Signed-off-by: NLi RongQing <lirongqing@baidu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This avoids an indirect call per syscall for common ipv4 transports

v1 -> v2:
 - avoid unneeded reclaration for udp_sendmsg, as suggested by Willem
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The same code is replicated verbatim in multiple places, and the next
patches will introduce an additional user for it. Factor out a
helper and use it where appropriate. No functional change intended.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

af_inet sets sock->sk to NULL which trips strparser over:

BUG: kernel NULL pointer dereference, address: 0000000000000012
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.2.0-rc1-00139-g14629453a6d3 #21
RIP: 0010:tcp_peek_len+0x10/0x60
RSP: 0018:ffffc02e41c54b98 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff9cf924c4e030 RCX: 0000000000000051
RDX: 0000000000000000 RSI: 000000000000000c RDI: ffff9cf97128f480
RBP: ffff9cf9365e0300 R08: ffff9cf94fe7d2c0 R09: 0000000000000000
R10: 000000000000036b R11: ffff9cf939735e00 R12: ffff9cf91ad9ae40
R13: ffff9cf924c4e000 R14: ffff9cf9a8fcbaae R15: 0000000000000020
FS: 0000000000000000(0000) GS:ffff9cf9af7c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000012 CR3: 000000013920a003 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
 <IRQ>
 strp_data_ready+0x48/0x90
 tls_data_ready+0x22/0xd0 [tls]
 tcp_rcv_established+0x569/0x620
 tcp_v4_do_rcv+0x127/0x1e0
 tcp_v4_rcv+0xad7/0xbf0
 ip_protocol_deliver_rcu+0x2c/0x1c0
 ip_local_deliver_finish+0x41/0x50
 ip_local_deliver+0x6b/0xe0
 ? ip_protocol_deliver_rcu+0x1c0/0x1c0
 ip_rcv+0x52/0xd0
 ? ip_rcv_finish_core.isra.20+0x380/0x380
 __netif_receive_skb_one_core+0x7e/0x90
 netif_receive_skb_internal+0x42/0xf0
 napi_gro_receive+0xed/0x150
 nfp_net_poll+0x7a2/0xd30 [nfp]
 ? kmem_cache_free_bulk+0x286/0x310
 net_rx_action+0x149/0x3b0
 __do_softirq+0xe3/0x30a
 ? handle_irq_event_percpu+0x6a/0x80
 irq_exit+0xe8/0xf0
 do_IRQ+0x85/0xd0
 common_interrupt+0xf/0xf
 </IRQ>
RIP: 0010:cpuidle_enter_state+0xbc/0x450

To avoid this issue set sock->sk after sk_prot->close.
My grepping and testing did not discover any code which
would depend on the current behaviour.

Fixes: c46234eb ("tls: RX path for ktls")
Reported-by: NDavid Beckett <david.beckett@netronome.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.
Acked-by: NStefan Schmidt <stefan@datenfreihafen.org>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As Eric noticed, in .sk_destruct, sk->sk_dst_cache update is prevented, and
no barrier is needed for this. So change to use rcu_dereference_protected()
instead of rcu_dereference_check() to fetch sk_dst_cache in there.

v1->v2:
  - no change, repost after net-next is open.
Reported-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Often times, recvmsg() system calls and BH handling for a particular
TCP socket are done on different cpus.

This means the incoming skb had to be allocated on a cpu,
but freed on another.

This incurs a high spinlock contention in slab layer for small rpc,
but also a high number of cache line ping pongs for larger packets.

A full size GRO packet might use 45 page fragments, meaning
that up to 45 put_page() can be involved.

More over performing the __kfree_skb() in the recvmsg() context
adds a latency for user applications, and increase probability
of trapping them in backlog processing, since the BH handler
might found the socket owned by the user.

This patch, combined with the prior one increases the rpc
performance by about 10 % on servers with large number of cores.

(tcp_rr workload with 10,000 flows and 112 threads reach 9 Mpps
 instead of 8 Mpps)

This also increases single bulk flow performance on 40Gbit+ links,
since in this case there are often two cpus working in tandem :

 - CPU handling the NIC rx interrupts, feeding the receive queue,
  and (after this patch) freeing the skbs that were consumed.

 - CPU in recvmsg() system call, essentially 100 % busy copying out
  data to user space.

Having at most one skb in a per-socket cache has very little risk
of memory exhaustion, and since it is protected by socket lock,
its management is essentially free.

Note that if rps/rfs is used, we do not enable this feature, because
there is high chance that the same cpu is handling both the recvmsg()
system call and the TCP rx path, but that another cpu did the skb
allocations in the device driver right before the RPS/RFS logic.

To properly handle this case, it seems we would need to record
on which cpu skb was allocated, and use a different channel
to give skbs back to this cpu.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSoheil Hassas Yeganeh <soheil@google.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 121d57af ("gso: validate gso_type in GSO handlers") added
gso_type validation to existing gso_segment callback functions, to
filter out illegal and potentially dangerous SKB_GSO_DODGY packets.

Convert tunnels that now call inet_gso_segment and ipv6_gso_segment
directly to have their own callbacks and extend validation to these.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This avoids an indirect call in the receive path for TCP and UDP
packets. TCP takes precedence on UDP, so that we have a single
additional conditional in the common case.

When IPV6 is build as module, all gro symbols except UDPv6 are
builtin, while the latter belong to the ipv6 module, so we
need some special care.

v1 -> v2:
 - adapted to INDIRECT_CALL_ changes
v2 -> v3:
 - fix build issue with CONFIG_IPV6=m
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set the backlog earlier in inet_dccp_listen() and inet_listen(),
then we can avoid the redundant setting.
Signed-off-by: NYafang Shao <laoar.shao@gmail.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a sysctl raw_l3mdev_accept to control raw socket lookup in a manner
similar to use of tcp_l3mdev_accept for stream and of udp_l3mdev_accept
for datagram sockets. Have this default to enabled for reasons of
backwards compatibility. This is so as to specify the output device
with cmsg and IP_PKTINFO, but using a socket not bound to the
corresponding VRF. This allows e.g. older ping implementations to be
run with specifying the device but without executing it in the VRF.
If the option is disabled, packets received in a VRF context are only
handled by a raw socket bound to the VRF, and correspondingly packets
in the default VRF are only handled by a socket not bound to any VRF.
Signed-off-by: NMike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: NDavid Ahern <dsahern@gmail.com>
Tested-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>