7852 Commits

Author SHA1 Message Date
Sebastian Andrzej Siewior
448e163f8b gen_stats: Add gnet_stats_add_queue().
This function will replace __gnet_stats_copy_queue(). It reads all
arguments and adds them into the passed gnet_stats_queue argument.
In contrast to __gnet_stats_copy_queue() it also copies the qlen member.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:41 +01:00
Sebastian Andrzej Siewior
fbf307c89e gen_stats: Add instead Set the value in __gnet_stats_copy_basic().
__gnet_stats_copy_basic() always assigns the value to the bstats
argument overwriting the previous value. The later added per-CPU version
always accumulated the values in the returning gnet_stats_basic_packed
argument.

Based on review there are five users of that function as of today:
- est_fetch_counters(), ___gnet_stats_copy_basic()
  memsets() bstats to zero, single invocation.

- mq_dump(), mqprio_dump(), mqprio_dump_class_stats()
  memsets() bstats to zero, multiple invocation but does not use the
  function due to !qdisc_is_percpu_stats().

Add the values in __gnet_stats_copy_basic() instead overwriting. Rename
the function to gnet_stats_add_basic() to make it more obvious.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18 12:54:40 +01:00
Kyungrok Chung
254ec036db net: make use of helper netif_is_bridge_master()
Make use of netdev helper functions to improve code readability.
Replace 'dev->priv_flags & IFF_EBRIDGE' with netif_is_bridge_master(dev).

Signed-off-by: Kyungrok Chung <acadx0@gmail.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16 15:02:56 +01:00
Jakub Kicinski
24bcbe1cc6 net: stream: don't purge sk_error_queue in sk_stream_kill_queues()
sk_stream_kill_queues() can be called on close when there are
still outstanding skbs to transmit. Those skbs may try to queue
notifications to the error queue (e.g. timestamps).
If sk_stream_kill_queues() purges the queue without taking
its lock the queue may get corrupted, and skbs leaked.

This shows up as a warning about an rmem leak:

WARNING: CPU: 24 PID: 0 at net/ipv4/af_inet.c:154 inet_sock_destruct+0x...

The leak is always a multiple of 0x300 bytes (the value is in
%rax on my builds, so RAX: 0000000000000300). 0x300 is truesize of
an empty sk_buff. Indeed if we dump the socket state at the time
of the warning the sk_error_queue is often (but not always)
corrupted. The ->next pointer points back at the list head,
but not the ->prev pointer. Indeed we can find the leaked skb
by scanning the kernel memory for something that looks like
an skb with ->sk = socket in question, and ->truesize = 0x300.
The contents of ->cb[] of the skb confirms the suspicion that
it is indeed a timestamp notification (as generated in
__skb_complete_tx_timestamp()).

Removing purging of sk_error_queue should be okay, since
inet_sock_destruct() does it again once all socket refs
are gone. Eric suggests this may cause sockets that go
thru disconnect() to maintain notifications from the
previous incarnations of the socket, but that should be
okay since the race was there anyway, and disconnect()
is not exactly dependable.

Thanks to Jonathan Lemon and Omar Sandoval for help at various
stages of tracing the issue.

Fixes: cb9eff097831 ("net: new user space API for time stamping of incoming and outgoing packets")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16 09:06:09 +01:00
Yunsheng Lin
d00e60ee54 page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA
As the 32-bit arch with 64-bit DMA seems to rare those days,
and page pool might carry a lot of code and complexity for
systems that possibly.

So disable dma mapping support for such systems, if drivers
really want to work on such systems, they have to implement
their own DMA-mapping fallback tracking outside page_pool.

Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 10:54:20 +01:00
Daniel Borkmann
30fc7efa38 net, neigh: Reject creating NUD_PERMANENT with NTF_MANAGED entries
The combination of NUD_PERMANENT + NTF_MANAGED is not supported and does
not make sense either given the former indicates a static/fixed neighbor
entry whereas the latter a dynamically resolved one. While it is possible
to transition from one over to the other, we should however reject such
creation attempts.

Fixes: 7482e3841d52 ("net, neigh: Add NTF_MANAGED flag for managed neighbor entries")
Suggested-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 19:16:21 -07:00
Daniel Borkmann
c8e80c1169 net, neigh: Use NLA_POLICY_MASK helper for NDA_FLAGS_EXT attribute
Instead of open-coding a check for invalid bits in NTF_EXT_MASK, we can just
use the NLA_POLICY_MASK() helper instead, and simplify NDA_FLAGS_EXT sanity
check this way.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 19:16:21 -07:00
Daniel Borkmann
507c2f1d29 net, neigh: Add build-time assertion to avoid neigh->flags overflow
Currently, NDA_FLAGS_EXT flags allow a maximum of 24 bits to be used for
extended neighbor flags. These are eventually fed into neigh->flags by
shifting with NTF_EXT_SHIFT as per commit 2c611ad97a82 ("net, neigh:
Extend neigh->flags to 32 bit to allow for extensions").

If really ever needed in future, the full 32 bits from NDA_FLAGS_EXT can
be used, it would only require to move neigh->flags from u32 to u64 inside
the kernel.

Add a build-time assertion such that when extending the NTF_EXT_MASK with
new bits, we'll trigger an error once we surpass the 24th bit. This assumes
that no bit holes in new NTF_EXT_* flags will slip in from UAPI, but I
think this is reasonable to assume.

Suggested-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 19:16:21 -07:00
Jakub Kicinski
e15f5972b8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/ioam6.sh
  7b1700e009cc ("selftests: net: modify IOAM tests for undef bits")
  bf77b1400a56 ("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
Lukas Wunner
42df6e1d22 netfilter: Introduce egress hook
Support classifying packets with netfilter on egress to satisfy user
requirements such as:
* outbound security policies for containers (Laura)
* filtering and mangling intra-node Direct Server Return (DSR) traffic
  on a load balancer (Laura)
* filtering locally generated traffic coming in through AF_PACKET,
  such as local ARP traffic generated for clustering purposes or DHCP
  (Laura; the AF_PACKET plumbing is contained in a follow-up commit)
* L2 filtering from ingress and egress for AVB (Audio Video Bridging)
  and gPTP with nftables (Pablo)
* in the future: in-kernel NAT64/NAT46 (Pablo)

The egress hook introduced herein complements the ingress hook added by
commit e687ad60af09 ("netfilter: add netfilter ingress hook after
handle_ing() under unique static key").  A patch for nftables to hook up
egress rules from user space has been submitted separately, so users may
immediately take advantage of the feature.

Alternatively or in addition to netfilter, packets can be classified
with traffic control (tc).  On ingress, packets are classified first by
tc, then by netfilter.  On egress, the order is reversed for symmetry.
Conceptually, tc and netfilter can be thought of as layers, with
netfilter layered above tc.

Traffic control is capable of redirecting packets to another interface
(man 8 tc-mirred).  E.g., an ingress packet may be redirected from the
host namespace to a container via a veth connection:
tc ingress (host) -> tc egress (veth host) -> tc ingress (veth container)

In this case, netfilter egress classifying is not performed when leaving
the host namespace!  That's because the packet is still on the tc layer.
If tc redirects the packet to a physical interface in the host namespace
such that it leaves the system, the packet is never subjected to
netfilter egress classifying.  That is only logical since it hasn't
passed through netfilter ingress classifying either.

Packets can alternatively be redirected at the netfilter layer using
nft fwd.  Such a packet *is* subjected to netfilter egress classifying
since it has reached the netfilter layer.

Internally, the skb->nf_skip_egress flag controls whether netfilter is
invoked on egress by __dev_queue_xmit().  Because __dev_queue_xmit() may
be called recursively by tunnel drivers such as vxlan, the flag is
reverted to false after sch_handle_egress().  This ensures that
netfilter is applied both on the overlay and underlying network.

Interaction between tc and netfilter is possible by setting and querying
skb->mark.

If netfilter egress classifying is not enabled on any interface, it is
patched out of the data path by way of a static_key and doesn't make a
performance difference that is discernible from noise:

Before:             1537 1538 1538 1537 1538 1537 Mb/sec
After:              1536 1534 1539 1539 1539 1540 Mb/sec
Before + tc accept: 1418 1418 1418 1419 1419 1418 Mb/sec
After  + tc accept: 1419 1424 1418 1419 1422 1420 Mb/sec
Before + tc drop:   1620 1619 1619 1619 1620 1620 Mb/sec
After  + tc drop:   1616 1624 1625 1624 1622 1619 Mb/sec

When netfilter egress classifying is enabled on at least one interface,
a minimal performance penalty is incurred for every egress packet, even
if the interface it's transmitted over doesn't have any netfilter egress
rules configured.  That is caused by checking dev->nf_hooks_egress
against NULL.

Measurements were performed on a Core i7-3615QM.  Commands to reproduce:
ip link add dev foo type dummy
ip link set dev foo up
modprobe pktgen
echo "add_device foo" > /proc/net/pktgen/kpktgend_3
samples/pktgen/pktgen_bench_xmit_mode_queue_xmit.sh -i foo -n 400000000 -m "11:11:11:11:11:11" -d 1.1.1.1

Accept all traffic with tc:
tc qdisc add dev foo clsact
tc filter add dev foo egress bpf da bytecode '1,6 0 0 0,'

Drop all traffic with tc:
tc qdisc add dev foo clsact
tc filter add dev foo egress bpf da bytecode '1,6 0 0 2,'

Apply this patch when measuring packet drops to avoid errors in dmesg:
https://lore.kernel.org/netdev/a73dda33-57f4-95d8-ea51-ed483abd6a7a@iogearbox.net/

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Laura García Liébana <nevola@gmail.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:06:28 +02:00
Lukas Wunner
17d2078422 netfilter: Generalize ingress hook include file
Prepare for addition of a netfilter egress hook by generalizing the
ingress hook include file.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:00:59 +02:00
Lukas Wunner
7463acfbe5 netfilter: Rename ingress hook include file
Prepare for addition of a netfilter egress hook by renaming
<linux/netfilter_ingress.h> to <linux/netfilter_netdev.h>.

The egress hook also necessitates a refactoring of the include file,
but that is done in a separate commit to ease reviewing.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:00:58 +02:00
Vladimir Oltean
1f922d9e37 Revert "net: procfs: add seq_puts() statement for dev_mcast"
This reverts commit ec18e8455484370d633a718c6456ddbf6eceef21.

It turns out that there are user space programs which got broken by that
change. One example is the "ifstat" program shipped by Debian:
https://packages.debian.org/source/bullseye/ifstat
which, confusingly enough, seems to not have anything in common with the
much more familiar (at least to me) ifstat program from iproute2:
https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/tree/misc/ifstat.c

root@debian:~# ifstat
ifstat: /proc/net/dev: unsupported format.

This change modified the header (first two lines of text) in
/proc/net/dev so that it looks like this:

root@debian:~# cat /proc/net/dev
Interface|                            Receive                                       |                                 Transmit
         |            bytes      packets errs   drop fifo frame compressed multicast|            bytes      packets errs   drop fifo colls carrier compressed
       lo:            97400         1204    0      0    0     0          0         0            97400         1204    0      0    0     0       0          0
    bond0:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
     sit0:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
     eno2:          5002206         6651    0      0    0     0          0         0        105518642      1465023    0      0    0     0       0          0
     swp0:           134531         2448    0      0    0     0          0         0         99599598      1464381    0      0    0     0       0          0
     swp1:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
     swp2:          4867675         4203    0      0    0     0          0         0            58134          631    0      0    0     0       0          0
    sw0p0:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
    sw0p1:           124739         2448    0   1422    0     0          0         0         93741184      1464369    0      0    0     0       0          0
    sw0p2:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
    sw2p0:          4850863         4203    0      0    0     0          0         0            54722          619    0      0    0     0       0          0
    sw2p1:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
    sw2p2:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
    sw2p3:                0            0    0      0    0     0          0         0                0            0    0      0    0     0       0          0
      br0:            10508          212    0    212    0     0          0       212         61369558       958857    0      0    0     0       0          0

whereas before it looked like this:

root@debian:~# cat /proc/net/dev
Inter-|   Receive                                                |  Transmit
 face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
    lo:   13160     164    0    0    0     0          0         0    13160     164    0    0    0     0       0          0
 bond0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
  sit0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
  eno2:   30824     268    0    0    0     0          0         0     3332      37    0    0    0     0       0          0
  swp0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
  swp1:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
  swp2:   30824     268    0    0    0     0          0         0     2428      27    0    0    0     0       0          0
 sw0p0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 sw0p1:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 sw0p2:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 sw2p0:   29752     268    0    0    0     0          0         0     1564      17    0    0    0     0       0          0
 sw2p1:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 sw2p2:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0
 sw2p3:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0

The reason why the ifstat shipped by Debian (v1.1, with a Debian patch
upgrading it to 1.1-8.1 at the time of writing) is broken is because its
"proc" driver/backend parses the header very literally:

main/drivers.c#L825
  if (!data->checked && strncmp(buf, "Inter-|", 7))
    goto badproc;

and there's no way in which the header can be changed such that programs
parsing like that would not get broken.

Even if we fix this ancient and very "lightly" maintained program to
parse the text output of /proc/net/dev in a more sensible way, this
story seems bound to repeat again with other programs, and modifying
them all could cause more trouble than it's worth. On the other hand,
the reverted patch had no other reason than an aesthetic one, so
reverting it is the simplest way out.

I don't know what other distributions would be affected; the fact that
Debian doesn't ship the iproute2 version of the program (a different
code base altogether, which uses netlink and not /proc/net/dev) is
surprising in itself.

Fixes: ec18e8455484 ("net: procfs: add seq_puts() statement for dev_mcast")
Link: https://lore.kernel.org/netdev/20211009163511.vayjvtn3rrteglsu@skbuf/
Cc: Yajun Deng <yajun.deng@linux.dev>
Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20211013001909.3164185-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-13 17:24:38 -07:00
Leon Romanovsky
82465bec3e devlink: Delete reload enable/disable interface
Commit a0c76345e3d3 ("devlink: disallow reload operation during device
cleanup") added devlink_reload_{enable,disable}() APIs to prevent reload
operation from racing with device probe/dismantle.

After recent changes to move devlink_register() to the end of device
probe and devlink_unregister() to the beginning of device dismantle,
these races can no longer happen. Reload operations will be denied if
the devlink instance is unregistered and devlink_unregister() will block
until all in-flight operations are done.

Therefore, remove these devlink_reload_{enable,disable}() APIs.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 16:29:17 -07:00
Leon Romanovsky
bd032e35c5 devlink: Allow control devlink ops behavior through feature mask
Introduce new devlink call to set feature mask to control devlink
behavior during device initialization phase after devlink_alloc()
is already called.

This allows us to set reload ops based on device property which
is not known at the beginning of driver initialization.

For the sake of simplicity, this API lacks any type of locking and
needs to be called before devlink_register() to make sure that no
parallel access to the ops is possible at this stage.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 16:29:17 -07:00
Leon Romanovsky
b88f7b1203 devlink: Annotate devlink API calls
Initial annotation patch to separate calls that needs to be executed
before or after devlink_register().

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 16:29:17 -07:00
Leon Romanovsky
2bc50987dc devlink: Move netdev_to_devlink helpers to devlink.c
Both netdev_to_devlink and netdev_to_devlink_port are used in devlink.c
only, so move them in order to reduce their scope.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 16:29:16 -07:00
Leon Romanovsky
21314638c9 devlink: Reduce struct devlink exposure
The declaration of struct devlink in general header provokes the
situation where internal fields can be accidentally used by the driver
authors. In order to reduce such possible situations, let's reduce the
namespace exposure of struct devlink.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 16:29:16 -07:00
Daniel Borkmann
7482e3841d net, neigh: Add NTF_MANAGED flag for managed neighbor entries
Allow a user space control plane to insert entries with a new NTF_EXT_MANAGED
flag. The flag then indicates to the kernel that the neighbor entry should be
periodically probed for keeping the entry in NUD_REACHABLE state iff possible.

The use case for this is targeting XDP or tc BPF load-balancers which use
the bpf_fib_lookup() BPF helper in order to piggyback on neighbor resolution
for their backends. Given they cannot be resolved in fast-path, a control
plane inserts the L3 (without L2) entries manually into the neighbor table
and lets the kernel do the neighbor resolution either on the gateway or on
the backend directly in case the latter resides in the same L2. This avoids
to deal with L2 in the control plane and to rebuild what the kernel already
does best anyway.

NTF_EXT_MANAGED can be combined with NTF_EXT_LEARNED in order to avoid GC
eviction. The kernel then adds NTF_MANAGED flagged entries to a per-neighbor
table which gets triggered by the system work queue to periodically call
neigh_event_send() for performing the resolution. The implementation allows
migration from/to NTF_MANAGED neighbor entries, so that already existing
entries can be converted by the control plane if needed. Potentially, we could
make the interval for periodically calling neigh_event_send() configurable;
right now it's set to DELAY_PROBE_TIME which is also in line with mlxsw which
has similar driver-internal infrastructure c723c735fa6b ("mlxsw: spectrum_router:
Periodically update the kernel's neigh table"). In future, the latter could
possibly reuse the NTF_MANAGED neighbors as well.

Example:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 managed extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a managed extern_learn REACHABLE
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Link: https://linuxplumbersconf.org/event/11/contributions/953/
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12 11:27:47 +01:00
Roopa Prabhu
2c611ad97a net, neigh: Extend neigh->flags to 32 bit to allow for extensions
Currently, all bits in struct ndmsg's ndm_flags are used up with the most
recent addition of 435f2e7cc0b7 ("net: bridge: add support for sticky fdb
entries"). This makes it impossible to extend the neighboring subsystem
with new NTF_* flags:

  struct ndmsg {
    __u8   ndm_family;
    __u8   ndm_pad1;
    __u16  ndm_pad2;
    __s32  ndm_ifindex;
    __u16  ndm_state;
    __u8   ndm_flags;
    __u8   ndm_type;
  };

There are ndm_pad{1,2} attributes which are not used. However, due to
uncareful design, the kernel does not enforce them to be zero upon new
neighbor entry addition, and given they've been around forever, it is
not possible to reuse them today due to risk of breakage. One option to
overcome this limitation is to add a new NDA_FLAGS_EXT attribute for
extended flags.

In struct neighbour, there is a 3 byte hole between protocol and ha_lock,
which allows neigh->flags to be extended from 8 to 32 bits while still
being on the same cacheline as before. This also allows for all future
NTF_* flags being in neigh->flags rather than yet another flags field.
Unknown flags in NDA_FLAGS_EXT will be rejected by the kernel.

Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12 11:27:47 +01:00
Daniel Borkmann
3dc20f4762 net, neigh: Enable state migration between NUD_PERMANENT and NTF_USE
Currently, it is not possible to migrate a neighbor entry between NUD_PERMANENT
state and NTF_USE flag with a dynamic NUD state from a user space control plane.
Similarly, it is not possible to add/remove NTF_EXT_LEARNED flag from an existing
neighbor entry in combination with NTF_USE flag.

This is due to the latter directly calling into neigh_event_send() without any
meta data updates as happening in __neigh_update(). Thus, to enable this use
case, extend the latter with a NEIGH_UPDATE_F_USE flag where we break the
NUD_PERMANENT state in particular so that a latter neigh_event_send() is able
to re-resolve a neighbor entry.

Before fix, NUD_PERMANENT -> NUD_* & NTF_USE:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT
  [...]

As can be seen, despite the admin-triggered replace, the entry remains in the
NUD_PERMANENT state.

After fix, NUD_PERMANENT -> NUD_* & NTF_USE:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE
  [...]
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn STALE
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a PERMANENT
  [...]

After the fix, the admin-triggered replace switches to a dynamic state from
the NTF_USE flag which triggered a new neighbor resolution. Likewise, we can
transition back from there, if needed, into NUD_PERMANENT.

Similar before/after behavior can be observed for below transitions:

Before fix, NTF_USE -> NTF_USE | NTF_EXT_LEARNED -> NTF_USE:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE
  [...]

After fix, NTF_USE -> NTF_USE | NTF_EXT_LEARNED -> NTF_USE:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE
  [...]
  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE
  [..]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12 11:27:47 +01:00
Daniel Borkmann
e4400bbf5b net, neigh: Fix NTF_EXT_LEARNED in combination with NTF_USE
The NTF_EXT_LEARNED neigh flag is usually propagated back to user space
upon dump of the neighbor table. However, when used in combination with
NTF_USE flag this is not the case despite exempting the entry from the
garbage collector. This results in inconsistent state since entries are
typically marked in neigh->flags with NTF_EXT_LEARNED, but here they are
not. Fix it by propagating the creation flag to ___neigh_create().

Before fix:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a REACHABLE
  [...]

After fix:

  # ./ip/ip n replace 192.168.178.30 dev enp5s0 use extern_learn
  # ./ip/ip n
  192.168.178.30 dev enp5s0 lladdr f4:8c:50:5e:71:9a extern_learn REACHABLE
  [...]

Fixes: 9ce33e46531d ("neighbour: support for NTF_EXT_LEARNED flag")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12 11:27:47 +01:00
Antoine Tenart
c0288ae8e6 net: make dev_get_port_parent_id slightly more readable
Cosmetic commit making dev_get_port_parent_id slightly more readable.
There is no need to split the condition to return after calling
devlink_compat_switch_id_get and after that 'recurse' is always true.

Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-10 11:29:14 +01:00
Antoine Tenart
75ea27d0d6 net: introduce a function to check if a netdev name is in use
__dev_get_by_name is currently used to either retrieve a net device
reference using its name or to check if a name is already used by a
registered net device (per ns). In the later case there is no need to
return a reference to a net device.

Introduce a new helper, netdev_name_in_use, to check if a name is
currently used by a registered net device without leaking a reference
the corresponding net device. This helper uses netdev_name_node_lookup
instead of __dev_get_by_name as we don't need the extra logic retrieving
a reference to the corresponding net device.

Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08 17:02:34 +01:00
Richard Palethorpe
4c1e34c0db vsock: Enable y2038 safe timeval for timeout
Reuse the timeval compat code from core/sock to handle 32-bit and
64-bit timeval structures. Also introduce a new socket option define
to allow using y2038 safe timeval under 32-bit.

The existing behavior of sock_set_timeout and vsock's timeout setter
differ when the time value is out of bounds. vsocks current behavior
is retained at the expense of not being able to share the full
implementation.

This allows the LTP test vsock01 to pass under 32-bit compat mode.

Fixes: fe0c72f3db11 ("socket: move compat timeout handling into sock.c")
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Cc: Richard Palethorpe <rpalethorpe@richiejp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08 16:21:53 +01:00
Antoine Tenart
146e5e7333 net-sysfs: try not to restart the syscall if it will fail eventually
Due to deadlocks in the networking subsystem spotted 12 years ago[1],
a workaround was put in place[2] to avoid taking the rtnl lock when it
was not available and restarting the syscall (back to VFS, letting
userspace spin). The following construction is found a lot in the net
sysfs and sysctl code:

  if (!rtnl_trylock())
          return restart_syscall();

This can be problematic when multiple userspace threads use such
interfaces in a short period, making them to spin a lot. This happens
for example when adding and moving virtual interfaces: userspace
programs listening on events, such as systemd-udevd and NetworkManager,
do trigger actions reading files in sysfs. It gets worse when a lot of
virtual interfaces are created concurrently, say when creating
containers at boot time.

Returning early without hitting the above pattern when the syscall will
fail eventually does make things better. While it is not a fix for the
issue, it does ease things.

[1] https://lore.kernel.org/netdev/49A4D5D5.5090602@trash.net/
    https://lore.kernel.org/netdev/m14oyhis31.fsf@fess.ebiederm.org/
    and https://lore.kernel.org/netdev/20090226084924.16cb3e08@nehalam/
[2] Rightfully, those deadlocks are *hard* to solve.

Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-08 15:24:02 +01:00
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
Jakub Kicinski
d466effe28 of: net: add a helper for loading netdev->dev_addr
Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
of VLANs...") introduced a rbtree for faster Ethernet address look
up. To maintain netdev->dev_addr in this tree we need to make all
the writes to it got through appropriate helpers.

There are roughly 40 places where netdev->dev_addr is passed
as the destination to a of_get_mac_address() call. Add a helper
which takes a dev pointer instead, so it can call an appropriate
helper.

Note that of_get_mac_address() already assumes the address is
6 bytes long (ETH_ALEN) so use eth_hw_addr_set().

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-07 13:39:51 +01:00
Jakub Kicinski
e330fb1459 of: net: move of_net under net/
Rob suggests to move of_net.c from under drivers/of/ somewhere
to the networking code.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-07 13:39:51 +01:00
Eric Dumazet
d343679919 rtnetlink: fix if_nlmsg_stats_size() under estimation
rtnl_fill_statsinfo() is filling skb with one mandatory if_stats_msg structure.

nlmsg_put(skb, pid, seq, type, sizeof(struct if_stats_msg), flags);

But if_nlmsg_stats_size() never considered the needed storage.

This bug did not show up because alloc_skb(X) allocates skb with
extra tailroom, because of added alignments. This could very well
be changed in the future to have deterministic behavior.

Fixes: 10c9ead9f3c6 ("rtnetlink: add new RTM_GETSTATS message to dump link stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-06 15:09:46 +01:00
Gyumin Hwang
1643771eeb net:dev: Change napi_gro_complete return type to void
napi_gro_complete always returned the same value, NET_RX_SUCCESS
And the value was not used anywhere

Signed-off-by: Gyumin Hwang <hkm73560@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-02 14:08:14 +01:00
Jacob Keller
a70e3f024d devlink: report maximum number of snapshots with regions
Each region has an independently configurable number of maximum
snapshots. This information is not reported to userspace, making it not
very discoverable. Fix this by adding a new
DEVLINK_ATTR_REGION_MAX_SNAPSHOST attribute which is used to report this
maximum.

Ex:

  $devlink region
  pci/0000:af:00.0/nvm-flash: size 10485760 snapshot [] max 1
  pci/0000:af:00.0/device-caps: size 4096 snapshot [] max 10
  pci/0000:af:00.1/nvm-flash: size 10485760 snapshot [] max 1
  pci/0000:af:00.1/device-caps: size 4096 snapshot [] max 10

This information enables users to understand why a new region command
may fail due to having too many existing snapshots.

Reported-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-01 14:28:55 +01:00
Jakub Kicinski
dd9a887b35 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/phy/bcm7xxx.c
  d88fd1b546ff ("net: phy: bcm7xxx: Fixed indirect MMD operations")
  f68d08c437f9 ("net: phy: bcm7xxx: Add EPHY entry for 72165")

net/sched/sch_api.c
  b193e15ac69d ("net: prevent user from passing illegal stab size")
  69508d43334e ("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
35306eb238 af_unix: fix races in sk_peer_pid and sk_peer_cred accesses
Jann Horn reported that SO_PEERCRED and SO_PEERGROUPS implementations
are racy, as af_unix can concurrently change sk_peer_pid and sk_peer_cred.

In order to fix this issue, this patch adds a new spinlock that needs
to be used whenever these fields are read or written.

Jann also pointed out that l2cap_sock_get_peer_pid_cb() is currently
reading sk->sk_peer_pid which makes no sense, as this field
is only possibly set by AF_UNIX sockets.
We will have to clean this in a separate patch.
This could be done by reverting b48596d1dc25 "Bluetooth: L2CAP: Add get_peer_pid callback"
or implementing what was truly expected.

Fixes: 109f6e39fa07 ("af_unix: Allow SO_PEERCRED to work across namespaces.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 14:18:40 +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
Jakub Kicinski
a5b8fd6578 net: dev_addr_list: handle first address in __hw_addr_add_ex
struct dev_addr_list is used for device addresses, unicast addresses
and multicast addresses. The first of those needs special handling
of the main address - netdev->dev_addr points directly the data
of the entry and drivers write to it freely, so we can't maintain
it in the rbtree (for now, at least, to be fixed in net-next).

Current work around sprinkles special handling of the first
address on the list throughout the code but it missed the case
where address is being added. First address will not be visible
during subsequent adds.

Syzbot found a warning where unicast addresses are modified
without holding the rtnl lock, tl;dr is that team generates
the same modification multiple times, not necessarily when
right locks are held.

In the repro we have:

  macvlan -> team -> veth

macvlan adds a unicast address to the team. Team then pushes
that address down to its memebers (veths). Next something unrelated
makes team sync member addrs again, and because of the bug
the addr entries get duplicated in the veths. macvlan gets
removed, removes its addr from team which removes only one
of the duplicated addresses from veths. This removal is done
under rtnl. Next syzbot uses iptables to add a multicast addr
to team (which does not hold rtnl lock). Team syncs veth addrs,
but because veths' unicast list still has the duplicate it will
also get sync, even though this update is intended for mc addresses.
Again, uc address updates need rtnl lock, boom.

Reported-by: syzbot+7a2ab2cdc14d134de553@syzkaller.appspotmail.com
Fixes: 406f42fa0d3c ("net-next: When a bond have a massive amount of VLANs with IPv6 addresses, performance of changing link state, attaching a VRF, changing an IPv6 address, etc. go down dramtically.")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:29:09 +01:00
Boris Sukholitko
2e861e5e97 dissector: do not set invalid PPP protocol
The following flower filter fails to match non-PPP_IP{V6} packets
wrapped in PPP_SES protocol:

tc filter add dev eth0 ingress protocol ppp_ses flower \
        action simple sdata hi64

The reason is that proto local variable is being set even when
FLOW_DISSECT_RET_OUT_BAD status is returned.

The fix is to avoid setting proto variable if the PPP protocol is unknown.

Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:09:28 +01:00
Paolo Abeni
4905455628 net: introduce and use lock_sock_fast_nested()
Syzkaller reported a false positive deadlock involving
the nl socket lock and the subflow socket lock:

MPTCP: kernel_bind error, err=-98
============================================
WARNING: possible recursive locking detected
5.15.0-rc1-syzkaller #0 Not tainted
--------------------------------------------
syz-executor998/6520 is trying to acquire lock:
ffff8880795718a0 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738

but task is already holding lock:
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

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

       CPU0
       ----
  lock(k-sk_lock-AF_INET);
  lock(k-sk_lock-AF_INET);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz-executor998/6520:
 #0: ffffffff8d176c50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

stack backtrace:
CPU: 1 PID: 6520 Comm: syz-executor998 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline]
 check_deadlock kernel/locking/lockdep.c:2987 [inline]
 validate_chain kernel/locking/lockdep.c:3776 [inline]
 __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 lock_sock_fast+0x36/0x100 net/core/sock.c:3229
 mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 __sock_release net/socket.c:649 [inline]
 sock_release+0x87/0x1b0 net/socket.c:677
 mptcp_pm_nl_create_listen_socket+0x238/0x2c0 net/mptcp/pm_netlink.c:900
 mptcp_nl_cmd_add_addr+0x359/0x930 net/mptcp/pm_netlink.c:1170
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_no_sendpage+0x101/0x150 net/core/sock.c:2980
 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504
 kernel_sendpage net/socket.c:3501 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:1003
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x110/0x180 fs/splice.c:936
 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891
 do_splice_direct+0x1b3/0x280 fs/splice.c:979
 do_sendfile+0xae9/0x1240 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f215cb69969
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc96bb3868 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f215cbad072 RCX: 00007f215cb69969
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007ffc96bb3a08 R09: 00007ffc96bb3a08
R10: 0000000100000002 R11: 0000000000000246 R12: 00007ffc96bb387c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000

the problem originates from uncorrect lock annotation in the mptcp
code and is only visible since commit 2dcb96bacce3 ("net: core: Correct
the sock::sk_lock.owned lockdep annotations"), but is present since
the port-based endpoint support initial implementation.

This patch addresses the issue introducing a nested variant of
lock_sock_fast() and using it in the relevant code path.

Fixes: 1729cf186d8a ("mptcp: create the listening socket for new port")
Fixes: 2dcb96bacce3 ("net: core: Correct the sock::sk_lock.owned lockdep annotations")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Reported-and-tested-by: syzbot+1dd53f7a89b299d59eaf@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:06:47 +01:00
Leon Romanovsky
ef91abfb20 devlink: Add missed notifications iterators
The commit mentioned in Fixes line missed a couple of notifications that
were registered before devlink_register() and should be delayed too.

As such, the too early placed WARN_ON() check spotted it.

WARNING: CPU: 1 PID: 6540 at net/core/devlink.c:5158 devlink_nl_region_notify+0x184/0x1e0 net/core/devlink.c:5158
Modules linked in:
CPU: 1 PID: 6540 Comm: syz-executor.0 Not tainted 5.15.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:devlink_nl_region_notify+0x184/0x1e0 net/core/devlink.c:5158
Code: 38 41 b8 c0 0c 00 00 31 d2 48 89 ee 4c 89 e7 e8 72 1a 26 00 48 83 c4 08 5b 5d 41 5c 41 5d 41 5e e9 01 bd 41 fa
e8 fc bc 41 fa <0f> 0b e9 f7 fe ff ff e8 f0 bc 41 fa 0f 0b eb da 4c 89 e7 e8 c4 18
RSP: 0018:ffffc90002d6f658 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801f08d580 RSI: ffffffff87344e94 RDI: 0000000000000003
RBP: ffff88801ee42100 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87344d8a R11: 0000000000000000 R12: ffff88801c1dc000
R13: 0000000000000000 R14: 000000000000002c R15: ffff88801c1dc070
FS:  0000555555e8e400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dd7c590310 CR3: 0000000069a09000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 devlink_region_create+0x39f/0x4c0 net/core/devlink.c:10327
 nsim_dev_dummy_region_init drivers/net/netdevsim/dev.c:481 [inline]
 nsim_dev_probe+0x5f6/0x1150 drivers/net/netdevsim/dev.c:1479
 call_driver_probe drivers/base/dd.c:517 [inline]
 really_probe+0x245/0xcc0 drivers/base/dd.c:596
 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
 __device_attach+0x228/0x4a0 drivers/base/dd.c:969
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
 device_add+0xc35/0x21b0 drivers/base/core.c:3359
 nsim_bus_dev_new drivers/net/netdevsim/bus.c:435 [inline]
 new_device_store+0x48b/0x770 drivers/net/netdevsim/bus.c:302
 bus_attr_store+0x72/0xa0 drivers/base/bus.c:122
 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139
 kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write+0x429/0x660 fs/read_write.c:507
 vfs_write+0x7cf/0xae0 fs/read_write.c:594
 ksys_write+0x12d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f328409d3ef
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 99 fd ff ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01
00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 cc fd ff ff 48
RSP: 002b:00007ffdc6851140 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f328409d3ef
RDX: 0000000000000003 RSI: 00007ffdc6851190 RDI: 0000000000000004
RBP: 0000000000000004 R08: 0000000000000000 R09: 00007ffdc68510e0
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f3284144971
R13: 00007ffdc6851190 R14: 0000000000000000 R15: 00007ffdc6851860

Fixes: cf530217408e ("devlink: Notify users when objects are accessible")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/2ed1159291f2a589b013914f2b60d8172fc525c1.1632925030.git.leonro@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-29 10:51:09 -07:00
Leon Romanovsky
cf53021740 devlink: Notify users when objects are accessible
The devlink core code notified users about add/remove objects without
relation if this object can be accessible or not. In this patch we unify
such user visible notifications in one place.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-27 16:31:58 +01:00
Jakub Kicinski
719c571970 net: make napi_disable() symmetric with enable
Commit 3765996e4f0b ("napi: fix race inside napi_enable") fixed
an ordering bug in napi_enable() and made the napi_enable() diverge
from napi_disable(). The state transitions done on disable are
not symmetric to enable.

There is no known bug in napi_disable() this is just refactoring.

Eric suggests we can also replace msleep(1) with a more opportunistic
usleep_range().

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-27 12:19:11 +01:00
Leon Romanovsky
8ba024dfaf devlink: Remove single line function obfuscations
There is no need in extra one line functions to call relevant
functions only once.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 14:12:57 +01:00
Leon Romanovsky
42ded61aa7 devlink: Delete not used port parameters APIs
There is no in-kernel users for the devlink port parameters API,
so let's remove it.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 14:12:56 +01:00
Jakub Kicinski
2fcd14d0f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
net/mptcp/protocol.c
  977d293e23b4 ("mptcp: ensure tx skbs always have the MPTCP ext")
  efe686ffce01 ("mptcp: ensure tx skbs always have the MPTCP ext")

same patch merged in both trees, keep net-next.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-23 11:19:49 -07:00
Li RongQing
a5df6333f1 skbuff: pass the result of data ksize to __build_skb_around
Avoid to call ksize again in __build_skb_around by passing
the result of data ksize to __build_skb_around

nginx stress test shows this change can reduce ksize cpu usage,
and give a little performance boost

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-22 14:20:01 +01:00
Leon Romanovsky
db4278c55f devlink: Make devlink_register to be void
devlink_register() can't fail and always returns success, but all drivers
are obligated to check returned status anyway. This adds a lot of boilerplate
code to handle impossible flow.

Make devlink_register() void and simplify the drivers that use that
API call.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Vladimir Oltean <olteanv@gmail.com> # dsa
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-22 14:15:12 +01:00
Xuan Zhuo
3765996e4f napi: fix race inside napi_enable
The process will cause napi.state to contain NAPI_STATE_SCHED and
not in the poll_list, which will cause napi_disable() to get stuck.

The prefix "NAPI_STATE_" is removed in the figure below, and
NAPI_STATE_HASHED is ignored in napi.state.

                      CPU0       |                   CPU1       | napi.state
===============================================================================
napi_disable()                   |                              | SCHED | NPSVC
napi_enable()                    |                              |
{                                |                              |
    smp_mb__before_atomic();     |                              |
    clear_bit(SCHED, &n->state); |                              | NPSVC
                                 | napi_schedule_prep()         | SCHED | NPSVC
                                 | napi_poll()                  |
                                 |   napi_complete_done()       |
                                 |   {                          |
                                 |      if (n->state & (NPSVC | | (1)
                                 |               _BUSY_POLL)))  |
                                 |           return false;      |
                                 |     ................         |
                                 |   }                          | SCHED | NPSVC
                                 |                              |
    clear_bit(NPSVC, &n->state); |                              | SCHED
}                                |                              |
                                 |                              |
napi_schedule_prep()             |                              | SCHED | MISSED (2)

(1) Here return direct. Because of NAPI_STATE_NPSVC exists.
(2) NAPI_STATE_SCHED exists. So not add napi.poll_list to sd->poll_list

Since NAPI_STATE_SCHED already exists and napi is not in the
sd->poll_list queue, NAPI_STATE_SCHED cannot be cleared and will always
exist.

1. This will cause this queue to no longer receive packets.
2. If you encounter napi_disable under the protection of rtnl_lock, it
   will cause the entire rtnl_lock to be locked, affecting the overall
   system.

This patch uses cmpxchg to implement napi_enable(), which ensures that
there will be no race due to the separation of clear two bits.

Fixes: 2d8bff12699abc ("netpoll: Close race condition between poll_one_napi and napi_disable")
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-20 09:41:29 +01:00
Yajun Deng
4fc2998983 net: rtnetlink: convert rcu_assign_pointer to RCU_INIT_POINTER
It no need barrier when assigning a NULL value to an RCU protected
pointer. So use RCU_INIT_POINTER() instead for more fast.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 12:56:02 +01:00
Thomas Gleixner
2dcb96bacc net: core: Correct the sock::sk_lock.owned lockdep annotations
lock_sock_fast() and lock_sock_nested() contain lockdep annotations for the
sock::sk_lock.owned 'mutex'. sock::sk_lock.owned is not a regular mutex. It
is just lockdep wise equivalent. In fact it's an open coded trivial mutex
implementation with some interesting features.

sock::sk_lock.slock is a regular spinlock protecting the 'mutex'
representation sock::sk_lock.owned which is a plain boolean. If 'owned' is
true, then some other task holds the 'mutex', otherwise it is uncontended.
As this locking construct is obviously endangered by lock ordering issues as
any other locking primitive it got lockdep annotated via a dedicated
dependency map sock::sk_lock.dep_map which has to be updated at the lock
and unlock sites.

lock_sock_nested() is a straight forward 'mutex' lock operation:

  might_sleep();
  spin_lock_bh(sock::sk_lock.slock)
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }

The lockdep annotation for sock::sk_lock.owned is for unknown reasons
_after_ the lock has been acquired, i.e. after the code block above and
after releasing sock::sk_lock.slock, but inside the bottom halves disabled
region:

  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();

The placement after the unlock is obvious because otherwise the
mutex_acquire() would nest into the spin lock held region.

But that's from the lockdep perspective still the wrong place:

 1) The mutex_acquire() is issued _after_ the successful acquisition which
    is pointless because in a dead lock scenario this point is never
    reached which means that if the deadlock is the first instance of
    exposing the wrong lock order lockdep does not have a chance to detect
    it.

 2) It only works because lockdep is rather lax on the context from which
    the mutex_acquire() is issued. Acquiring a mutex inside a bottom halves
    and therefore non-preemptible region is obviously invalid, except for a
    trylock which is clearly not the case here.

    This 'works' stops working on RT enabled kernels where the bottom halves
    serialization is done via a local lock, which exposes this misplacement
    because the 'mutex' and the local lock nest the wrong way around and
    lockdep complains rightfully about a lock inversion.

The placement is wrong since the initial commit a5b5bb9a053a ("[PATCH]
lockdep: annotate sk_locks") which introduced this.

Fix it by moving the mutex_acquire() in front of the actual lock
acquisition, which is what the regular mutex_lock() operation does as well.

lock_sock_fast() is not that straight forward. It looks at the first glance
like a convoluted trylock operation:

  spin_lock_bh(sock::sk_lock.slock)
  if (!sock::sk_lock.owned)
      return false;
  while (!try_lock(sock::sk_lock.owned)) {
      spin_unlock_bh(sock::sk_lock.slock);
      wait_for_release();
      spin_lock_bh(sock::sk_lock.slock);
  }
  spin_unlock(sock::sk_lock.slock);
  mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
  local_bh_enable();
  return true;

But that's not the case: lock_sock_fast() is an interesting optimization
for short critical sections which can run with bottom halves disabled and
sock::sk_lock.slock held. This allows to shortcut the 'mutex' operation in
the non contended case by preventing other lockers to acquire
sock::sk_lock.owned because they are blocked on sock::sk_lock.slock, which
in turn avoids the overhead of doing the heavy processing in release_sock()
including waking up wait queue waiters.

In the contended case, i.e. when sock::sk_lock.owned == true the behavior
is the same as lock_sock_nested().

Semantically this shortcut means, that the task acquired the 'mutex' even
if it does not touch the sock::sk_lock.owned field in the non-contended
case. Not telling lockdep about this shortcut acquisition is hiding
potential lock ordering violations in the fast path.

As a consequence the same reasoning as for the above lock_sock_nested()
case vs. the placement of the lockdep annotation applies.

The current placement of the lockdep annotation was just copied from
the original lock_sock(), now renamed to lock_sock_nested(),
implementation.

Fix this by moving the mutex_acquire() in front of the actual lock
acquisition and adding the corresponding mutex_release() into
unlock_sock_fast(). Also document the fast path return case with a comment.

Reported-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 12:48:06 +01:00
Yajun Deng
aed0826b0c net: net_namespace: Fix undefined member in key_remove_domain()
The key_domain member in struct net only exists if we define CONFIG_KEYS.
So we should add the define when we used key_domain.

Fixes: 9b242610514f ("keys: Network namespace domain tag")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 12:43:04 +01:00