Commit Graph

6747 Commits

Author SHA1 Message Date
David S. Miller
44ef976ab3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-03-13

The following pull-request contains BPF updates for your *net-next* tree.

We've added 86 non-merge commits during the last 12 day(s) which contain
a total of 107 files changed, 5771 insertions(+), 1700 deletions(-).

The main changes are:

1) Add modify_return attach type which allows to attach to a function via
   BPF trampoline and is run after the fentry and before the fexit programs
   and can pass a return code to the original caller, from KP Singh.

2) Generalize BPF's kallsyms handling and add BPF trampoline and dispatcher
   objects to be visible in /proc/kallsyms so they can be annotated in
   stack traces, from Jiri Olsa.

3) Extend BPF sockmap to allow for UDP next to existing TCP support in order
   in order to enable this for BPF based socket dispatch, from Lorenz Bauer.

4) Introduce a new bpftool 'prog profile' command which attaches to existing
   BPF programs via fentry and fexit hooks and reads out hardware counters
   during that period, from Song Liu. Example usage:

   bpftool prog profile id 337 duration 3 cycles instructions llc_misses

        4228 run_cnt
     3403698 cycles                                              (84.08%)
     3525294 instructions   #  1.04 insn per cycle               (84.05%)
          13 llc_misses     #  3.69 LLC misses per million isns  (83.50%)

5) Batch of improvements to libbpf, bpftool and BPF selftests. Also addition
   of a new bpf_link abstraction to keep in particular BPF tracing programs
   attached even when the applicaion owning them exits, from Andrii Nakryiko.

6) New bpf_get_current_pid_tgid() helper for tracing to perform PID filtering
   and which returns the PID as seen by the init namespace, from Carlos Neira.

7) Refactor of RISC-V JIT code to move out common pieces and addition of a
   new RV32G BPF JIT compiler, from Luke Nelson.

8) Add gso_size context member to __sk_buff in order to be able to know whether
   a given skb is GSO or not, from Willem de Bruijn.

9) Add a new bpf_xdp_output() helper which reuses XDP's existing perf RB output
   implementation but can be called from tracepoint programs, from Eelco Chaudron.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-13 20:52:03 -07:00
Björn Töpel
6a64037d4b bpf: Add bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER
Adding bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER,
so all the dispatchers have the common name prefix.

And also a small '_' cleanup for bpf_dispatcher_nopfunc function
name.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-03-13 12:49:51 -07:00
David S. Miller
1d34357931 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor overlapping changes, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 22:34:48 -07:00
Eelco Chaudron
d831ee84bf bpf: Add bpf_xdp_output() helper
Introduce new helper that reuses existing xdp perf_event output
implementation, but can be called from raw_tracepoint programs
that receive 'struct xdp_buff *' as a tracepoint argument.

Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/158348514556.2239.11050972434793741444.stgit@xdp-tutorial
2020-03-12 17:47:38 -07:00
Paul Blakey
ee1c45e875 flow_offload: Add flow_match_ct to get rule ct match
Add relevant getter for ct info dissector.

Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 15:00:39 -07:00
David S. Miller
bf3347c4d1 Merge branch 'ct-offload' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux 2020-03-12 12:34:23 -07:00
Julian Wiedmann
7c4046b1c5 Revert "net: sched: make newly activated qdiscs visible"
This reverts commit 4cda75275f
from net-next.

Brown bag time.

Michal noticed that this change doesn't work at all when
netif_set_real_num_tx_queues() gets called prior to an initial
dev_activate(), as for instance igb does.

Doing so dies with:

[   40.579142] BUG: kernel NULL pointer dereference, address: 0000000000000400
[   40.586922] #PF: supervisor read access in kernel mode
[   40.592668] #PF: error_code(0x0000) - not-present page
[   40.598405] PGD 0 P4D 0
[   40.601234] Oops: 0000 [#1] PREEMPT SMP PTI
[   40.605909] CPU: 18 PID: 1681 Comm: wickedd Tainted: G            E     5.6.0-rc3-ethnl.50-default #1
[   40.616205] Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.R3.27.D685.1305151734 05/15/2013
[   40.627377] RIP: 0010:qdisc_hash_add.part.22+0x2e/0x90
[   40.633115] Code: 00 55 53 89 f5 48 89 fb e8 2f 9b fb ff 85 c0 74 44 48 8b 43 40 48 8b 08 69 43 38 47 86 c8 61 c1 e8 1c 48 83 e8 80 48 8d 14 c1 <48> 8b 04 c1 48 8d 4b 28 48 89 53 30 48 89 43 28 48 85 c0 48 89 0a
[   40.654080] RSP: 0018:ffffb879864934d8 EFLAGS: 00010203
[   40.659914] RAX: 0000000000000080 RBX: ffffffffb8328d80 RCX: 0000000000000000
[   40.667882] RDX: 0000000000000400 RSI: 0000000000000000 RDI: ffffffffb831faa0
[   40.675849] RBP: 0000000000000000 R08: ffffa0752c8b9088 R09: ffffa0752c8b9208
[   40.683816] R10: 0000000000000006 R11: 0000000000000000 R12: ffffa0752d734000
[   40.691783] R13: 0000000000000008 R14: 0000000000000000 R15: ffffa07113c18000
[   40.699750] FS:  00007f94548e5880(0000) GS:ffffa0752e980000(0000) knlGS:0000000000000000
[   40.708782] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.715189] CR2: 0000000000000400 CR3: 000000082b6ae006 CR4: 00000000001606e0
[   40.723156] Call Trace:
[   40.725888]  dev_qdisc_set_real_num_tx_queues+0x61/0x90
[   40.731725]  netif_set_real_num_tx_queues+0x94/0x1d0
[   40.737286]  __igb_open+0x19a/0x5d0 [igb]
[   40.741767]  __dev_open+0xbb/0x150
[   40.745567]  __dev_change_flags+0x157/0x1a0
[   40.750240]  dev_change_flags+0x23/0x60

[...]

Fixes: 4cda75275f ("net: sched: make newly activated qdiscs visible")
Reported-by: Michal Kubecek <mkubecek@suse.cz>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Eric Dumazet <edumazet@google.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
CC: Cong Wang <xiyou.wangcong@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 11:19:24 -07:00
Julian Wiedmann
4cda75275f net: sched: make newly activated qdiscs visible
In their .attach callback, mq[prio] only add the qdiscs of the currently
active TX queues to the device's qdisc hash list.
If a user later increases the number of active TX queues, their qdiscs
are not visible via eg. 'tc qdisc show'.

Add a hook to netif_set_real_num_tx_queues() that walks all active
TX queues and adds those which are missing to the hash list.

CC: Eric Dumazet <edumazet@google.com>
CC: Jamal Hadi Salim <jhs@mojatatu.com>
CC: Cong Wang <xiyou.wangcong@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-11 23:17:28 -07:00
Lukas Wunner
1e09e5818b pktgen: Allow on loopback device
When pktgen is used to measure the performance of dev_queue_xmit()
packet handling in the core, it is preferable to not hand down
packets to a low-level Ethernet driver as it would distort the
measurements.

Allow using pktgen on the loopback device, thus constraining
measurements to core code.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-10 15:44:59 -07:00
Shakeel Butt
d752a49865 net: memcg: late association of sock to memcg
If a TCP socket is allocated in IRQ context or cloned from unassociated
(i.e. not associated to a memcg) in IRQ context then it will remain
unassociated for its whole life. Almost half of the TCPs created on the
system are created in IRQ context, so, memory used by such sockets will
not be accounted by the memcg.

This issue is more widespread in cgroup v1 where network memory
accounting is opt-in but it can happen in cgroup v2 if the source socket
for the cloning was created in root memcg.

To fix the issue, just do the association of the sockets at the accept()
time in the process context and then force charge the memory buffer
already used and reserved by the socket.

Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-10 15:33:05 -07:00
Dmitry Yakunin
018d26fcd1 cgroup, netclassid: periodically release file_lock on classid updating
In our production environment we have faced with problem that updating
classid in cgroup with heavy tasks cause long freeze of the file tables
in this tasks. By heavy tasks we understand tasks with many threads and
opened sockets (e.g. balancers). This freeze leads to an increase number
of client timeouts.

This patch implements following logic to fix this issue:
аfter iterating 1000 file descriptors file table lock will be released
thus providing a time gap for socket creation/deletion.

Now update is non atomic and socket may be skipped using calls:

dup2(oldfd, newfd);
close(oldfd);

But this case is not typical. Moreover before this patch skip is possible
too by hiding socket fd in unix socket buffer.

New sockets will be allocated with updated classid because cgroup state
is updated before start of the file descriptors iteration.

So in common cases this patch has no side effects.

Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-09 18:13:39 -07:00
Lorenz Bauer
7b98cd42b0 bpf: sockmap: Add UDP support
Allow adding hashed UDP sockets to sockmaps.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309111243.6982-9-lmb@cloudflare.com
2020-03-09 22:34:58 +01:00
Lorenz Bauer
cb21802b39 bpf: sockmap: Simplify sock_map_init_proto
We can take advantage of the fact that both callers of
sock_map_init_proto are holding a RCU read lock, and
have verified that psock is valid.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309111243.6982-7-lmb@cloudflare.com
2020-03-09 22:34:58 +01:00
Lorenz Bauer
f747632b60 bpf: sockmap: Move generic sockmap hooks from BPF TCP
The init, close and unhash handlers from TCP sockmap are generic,
and can be reused by UDP sockmap. Move the helpers into the sockmap code
base and expose them. This requires tcp_bpf_get_proto and tcp_bpf_clone to
be conditional on BPF_STREAM_PARSER.

The moved functions are unmodified, except that sk_psock_unlink is
renamed to sock_map_unlink to better match its behaviour.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309111243.6982-6-lmb@cloudflare.com
2020-03-09 22:34:58 +01:00
Lorenz Bauer
d19da360ee bpf: tcp: Move assertions into tcp_bpf_get_proto
We need to ensure that sk->sk_prot uses certain callbacks, so that
code that directly calls e.g. tcp_sendmsg in certain corner cases
works. To avoid spurious asserts, we must to do this only if
sk_psock_update_proto has not yet been called. The same invariants
apply for tcp_bpf_check_v6_needs_rebuild, so move the call as well.

Doing so allows us to merge tcp_bpf_init and tcp_bpf_reinit.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309111243.6982-4-lmb@cloudflare.com
2020-03-09 22:34:58 +01:00
Lorenz Bauer
7b70973d7e bpf: sockmap: Only check ULP for TCP sockets
The sock map code checks that a socket does not have an active upper
layer protocol before inserting it into the map. This requires casting
via inet_csk, which isn't valid for UDP sockets.

Guard checks for ULP by checking inet_sk(sk)->is_icsk first.

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309111243.6982-2-lmb@cloudflare.com
2020-03-09 22:34:58 +01:00
Willem de Bruijn
cf62089b0e bpf: Add gso_size to __sk_buff
BPF programs may want to know whether an skb is gso. The canonical
answer is skb_is_gso(skb), which tests that gso_size != 0.

Expose this field in the same manner as gso_segs. That field itself
is not a sufficient signal, as the comment in skb_shared_info makes
clear: gso_segs may be zero, e.g., from dodgy sources.

Also prepare net/bpf/test_run for upcoming BPF_PROG_TEST_RUN tests
of the feature.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200303200503.226217-2-willemdebruijn.kernel@gmail.com
2020-03-03 16:23:59 -08:00
Parav Pandit
acf1ee44ca devlink: Introduce devlink port flavour virtual
Currently mlx5 PCI PF and VF devlink devices register their ports as
physical port in non-representors mode.

Introduce a new port flavour as virtual so that virtual devices can
register 'virtual' flavour to make it more clear to users.

An example of one PCI PF and 2 PCI virtual functions, each having
one devlink port.

$ devlink port show
pci/0000:06:00.0/1: type eth netdev ens2f0 flavour physical port 0
pci/0000:06:00.2/1: type eth netdev ens2f2 flavour virtual port 0
pci/0000:06:00.3/1: type eth netdev ens2f3 flavour virtual port 0

Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03 15:40:40 -08:00
Jakub Kicinski
ff3b63b8c2 devlink: validate length of region addr/len
DEVLINK_ATTR_REGION_CHUNK_ADDR and DEVLINK_ATTR_REGION_CHUNK_LEN
lack entries in the netlink policy. Corresponding nla_get_u64()s
may read beyond the end of the message.

Fixes: 4e54795a27 ("devlink: Add support for region snapshot read command")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03 13:28:48 -08:00
Jakub Kicinski
8750939b6a devlink: validate length of param values
DEVLINK_ATTR_PARAM_VALUE_DATA may have different types
so it's not checked by the normal netlink policy. Make
sure the attribute length is what we expect.

Fixes: e3b7ca18ad ("devlink: Add param set command")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03 13:28:48 -08:00
David S. Miller
9f0ca0c1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-02-28

The following pull-request contains BPF updates for your *net-next* tree.

We've added 41 non-merge commits during the last 7 day(s) which contain
a total of 49 files changed, 1383 insertions(+), 499 deletions(-).

The main changes are:

1) BPF and Real-Time nicely co-exist.

2) bpftool feature improvements.

3) retrieve bpf_sk_storage via INET_DIAG.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-29 15:53:35 -08:00
Paolo Abeni
e427cad6ee net: datagram: drop 'destructor' argument from several helpers
The only users for such argument are the UDP protocol and the UNIX
socket family. We can safely reclaim the accounted memory directly
from the UDP code and, after the previous patch, we can do scm
stats accounting outside the datagram helpers.

Overall this cleans up a bit some datagram-related helpers, and
avoids an indirect call per packet in the UDP receive path.

v1 -> v2:
 - call scm_stat_del() only when not peeking - Kirill
 - fix build issue with CONFIG_INET_ESPINTCP

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28 12:12:53 -08:00
Gustavo A. R. Silva
d2afb41ae6 net: core: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28 12:08:37 -08:00
Martin KaFai Lau
1ed4d92458 bpf: INET_DIAG support in bpf_sk_storage
This patch adds INET_DIAG support to bpf_sk_storage.

1. Although this series adds bpf_sk_storage diag capability to inet sk,
   bpf_sk_storage is in general applicable to all fullsock.  Hence, the
   bpf_sk_storage logic will operate on SK_DIAG_* nlattr.  The caller
   will pass in its specific nesting nlattr (e.g. INET_DIAG_*) as
   the argument.

2. The request will be like:
	INET_DIAG_REQ_SK_BPF_STORAGES (nla_nest) (defined in latter patch)
		SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32)
		SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32)
		......

   Considering there could have multiple bpf_sk_storages in a sk,
   instead of reusing INET_DIAG_INFO ("ss -i"),  the user can select
   some specific bpf_sk_storage to dump by specifying an array of
   SK_DIAG_BPF_STORAGE_REQ_MAP_FD.

   If no SK_DIAG_BPF_STORAGE_REQ_MAP_FD is specified (i.e. an empty
   INET_DIAG_REQ_SK_BPF_STORAGES), it will dump all bpf_sk_storages
   of a sk.

3. The reply will be like:
	INET_DIAG_BPF_SK_STORAGES (nla_nest) (defined in latter patch)
		SK_DIAG_BPF_STORAGE (nla_nest)
			SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
			SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
		SK_DIAG_BPF_STORAGE (nla_nest)
			SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
			SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
		......

4. Unlike other INET_DIAG info of a sk which is pretty static, the size
   required to dump the bpf_sk_storage(s) of a sk is dynamic as the
   system adding more bpf_sk_storage_map.  It is hard to set a static
   min_dump_alloc size.

   Hence, this series learns it at the runtime and adjust the
   cb->min_dump_alloc as it iterates all sk(s) of a system.  The
   "unsigned int *res_diag_size" in bpf_sk_storage_diag_put()
   is for this purpose.

   The next patch will update the cb->min_dump_alloc as it
   iterates the sk(s).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200225230421.1975729-1-kafai@fb.com
2020-02-27 18:50:19 -08:00
David S. Miller
9f6e055907 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The mptcp conflict was overlapping additions.

The SMC conflict was an additional and removal happening at the same
time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-27 18:31:39 -08:00
Christian Brauner
ef6a4c88e9 net: fix sysfs permssions when device changes network namespace
Now that we moved all the helpers in place and make use netdev_change_owner()
to fixup the permissions when moving network devices between network
namespaces.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 20:07:26 -08:00
Christian Brauner
d755407d44 net-sysfs: add queue_change_owner()
Add a function to change the owner of the queue entries for a network device
when it is moved between network namespaces.

Currently, when moving network devices between network namespaces the
ownership of the corresponding queue sysfs entries are not changed. This leads
to problems when tools try to operate on the corresponding sysfs files. Fix
this.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 20:07:26 -08:00
Christian Brauner
e6dee9f389 net-sysfs: add netdev_change_owner()
Add a function to change the owner of a network device when it is moved
between network namespaces.

Currently, when moving network devices between network namespaces the
ownership of the corresponding sysfs entries is not changed. This leads
to problems when tools try to operate on the corresponding sysfs files.
This leads to a bug whereby a network device that is created in a
network namespaces owned by a user namespace will have its corresponding
sysfs entry owned by the root user of the corresponding user namespace.
If such a network device has to be moved back to the host network
namespace the permissions will still be set to the user namespaces. This
means unprivileged users can e.g. trigger uevents for such incorrectly
owned devices. They can also modify the settings of the device itself.
Both of these things are unwanted.

For example, workloads will create network devices in the host network
namespace. Other tools will then proceed to move such devices between
network namespaces owner by other user namespaces. While the ownership
of the device itself is updated in
net/core/net-sysfs.c:dev_change_net_namespace() the corresponding sysfs
entry for the device is not:

drwxr-xr-x 5 nobody nobody    0 Jan 25 18:08 .
drwxr-xr-x 9 nobody nobody    0 Jan 25 18:08 ..
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 addr_assign_type
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 addr_len
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 address
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 broadcast
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_changes
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_down_count
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 carrier_up_count
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dev_id
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dev_port
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 dormant
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 duplex
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 flags
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 gro_flush_timeout
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 ifalias
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 ifindex
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 iflink
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 link_mode
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 mtu
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 name_assign_type
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 netdev_group
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 operstate
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_port_id
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_port_name
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 phys_switch_id
drwxr-xr-x 2 nobody nobody    0 Jan 25 18:09 power
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 proto_down
drwxr-xr-x 4 nobody nobody    0 Jan 25 18:09 queues
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 speed
drwxr-xr-x 2 nobody nobody    0 Jan 25 18:09 statistics
lrwxrwxrwx 1 nobody nobody    0 Jan 25 18:08 subsystem -> ../../../../class/net
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:09 tx_queue_len
-r--r--r-- 1 nobody nobody 4096 Jan 25 18:09 type
-rw-r--r-- 1 nobody nobody 4096 Jan 25 18:08 uevent

However, if a device is created directly in the network namespace then
the device's sysfs permissions will be correctly updated:

drwxr-xr-x 5 root   root      0 Jan 25 18:12 .
drwxr-xr-x 9 nobody nobody    0 Jan 25 18:08 ..
-r--r--r-- 1 root   root   4096 Jan 25 18:12 addr_assign_type
-r--r--r-- 1 root   root   4096 Jan 25 18:12 addr_len
-r--r--r-- 1 root   root   4096 Jan 25 18:12 address
-r--r--r-- 1 root   root   4096 Jan 25 18:12 broadcast
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 carrier
-r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_changes
-r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_down_count
-r--r--r-- 1 root   root   4096 Jan 25 18:12 carrier_up_count
-r--r--r-- 1 root   root   4096 Jan 25 18:12 dev_id
-r--r--r-- 1 root   root   4096 Jan 25 18:12 dev_port
-r--r--r-- 1 root   root   4096 Jan 25 18:12 dormant
-r--r--r-- 1 root   root   4096 Jan 25 18:12 duplex
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 flags
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 gro_flush_timeout
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 ifalias
-r--r--r-- 1 root   root   4096 Jan 25 18:12 ifindex
-r--r--r-- 1 root   root   4096 Jan 25 18:12 iflink
-r--r--r-- 1 root   root   4096 Jan 25 18:12 link_mode
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 mtu
-r--r--r-- 1 root   root   4096 Jan 25 18:12 name_assign_type
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 netdev_group
-r--r--r-- 1 root   root   4096 Jan 25 18:12 operstate
-r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_port_id
-r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_port_name
-r--r--r-- 1 root   root   4096 Jan 25 18:12 phys_switch_id
drwxr-xr-x 2 root   root      0 Jan 25 18:12 power
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 proto_down
drwxr-xr-x 4 root   root      0 Jan 25 18:12 queues
-r--r--r-- 1 root   root   4096 Jan 25 18:12 speed
drwxr-xr-x 2 root   root      0 Jan 25 18:12 statistics
lrwxrwxrwx 1 nobody nobody    0 Jan 25 18:12 subsystem -> ../../../../class/net
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 tx_queue_len
-r--r--r-- 1 root   root   4096 Jan 25 18:12 type
-rw-r--r-- 1 root   root   4096 Jan 25 18:12 uevent

Now, when creating a network device in a network namespace owned by a
user namespace and moving it to the host the permissions will be set to
the id that the user namespace root user has been mapped to on the host
leading to all sorts of permission issues:

458752
drwxr-xr-x 5 458752 458752      0 Jan 25 18:12 .
drwxr-xr-x 9 root   root        0 Jan 25 18:08 ..
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 addr_assign_type
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 addr_len
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 address
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 broadcast
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_changes
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_down_count
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 carrier_up_count
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dev_id
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dev_port
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 dormant
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 duplex
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 flags
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 gro_flush_timeout
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 ifalias
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 ifindex
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 iflink
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 link_mode
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 mtu
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 name_assign_type
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 netdev_group
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 operstate
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_port_id
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_port_name
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 phys_switch_id
drwxr-xr-x 2 458752 458752      0 Jan 25 18:12 power
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 proto_down
drwxr-xr-x 4 458752 458752      0 Jan 25 18:12 queues
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 speed
drwxr-xr-x 2 458752 458752      0 Jan 25 18:12 statistics
lrwxrwxrwx 1 root   root        0 Jan 25 18:12 subsystem -> ../../../../class/net
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 tx_queue_len
-r--r--r-- 1 458752 458752   4096 Jan 25 18:12 type
-rw-r--r-- 1 458752 458752   4096 Jan 25 18:12 uevent

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 20:07:25 -08:00
Madhuparna Bhowmik
2eb51c75dc net: core: devlink.c: Use built-in RCU list checking
list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled.

The devlink->lock is held when devlink_dpipe_table_find()
is called in non RCU read side section. Therefore, pass struct devlink
to devlink_dpipe_table_find() for lockdep checking.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 16:59:18 -08:00
Amritha Nambiar
6e11d1578f net: Fix Tx hash bound checking
Fixes the lower and upper bounds when there are multiple TCs and
traffic is on the the same TC on the same device.

The lower bound is represented by 'qoffset' and the upper limit for
hash value is 'qcount + qoffset'. This gives a clean Rx to Tx queue
mapping when there are multiple TCs, as the queue indices for upper TCs
will be offset by 'qoffset'.

v2: Fixed commit description based on comments.

Fixes: 1b837d489e ("net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash")
Fixes: eadec877ce ("net: Add support for subordinate traffic classes to netdev_pick_tx")
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-26 11:14:10 -08:00
Jiri Pirko
5a2e106c74 devlink: extend devlink_trap_report() to accept cookie and pass
Add cookie argument to devlink_trap_report() allowing driver to pass in
the user cookie. Pass on the cookie down to drop monitor code.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-25 11:05:54 -08:00
Jiri Pirko
742b8cceaa drop_monitor: extend by passing cookie from driver
If driver passed along the cookie, push it through Netlink.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-25 11:05:54 -08:00
Jiri Pirko
85b0589ede devlink: add trap metadata type for cookie
Allow driver to indicate cookie metadata for registered traps.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-25 11:05:54 -08:00
Jiri Pirko
2008495d81 flow_offload: pass action cookie through offload structures
Extend struct flow_action_entry in order to hold TC action cookie
specified by user inserting the action.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-25 11:05:54 -08:00
David Miller
3d9f773cf2 bpf: Use bpf_prog_run_pin_on_cpu() at simple call sites.
All of these cases are strictly of the form:

	preempt_disable();
	BPF_PROG_RUN(...);
	preempt_enable();

Replace this with bpf_prog_run_pin_on_cpu() which wraps BPF_PROG_RUN()
with:

	migrate_disable();
	BPF_PROG_RUN(...);
	migrate_enable();

On non RT enabled kernels this maps to preempt_disable/enable() and on RT
enabled kernels this solely prevents migration, which is sufficient as
there is no requirement to prevent reentrancy to any BPF program from a
preempting task. The only requirement is that the program stays on the same
CPU.

Therefore, this is a trivially correct transformation.

The seccomp loop does not need protection over the loop. It only needs
protection per BPF filter program

[ tglx: Converted to bpf_prog_run_pin_on_cpu() ]

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.691493094@linutronix.de
2020-02-24 16:20:09 -08:00
Jiri Pirko
ecd942a0ef devlink: add ACL generic packet traps
Add packet traps that can report packets that were dropped during ACL
processing.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-24 11:55:06 -08:00
David Ahern
366ed1aca6 net: Remove unneeded export of a couple of xdp generic functions
generic_xdp_tx and xdp_do_generic_redirect are only used by builtin
code, so remove the EXPORT_SYMBOL_GPL for them.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-24 11:03:38 -08:00
Madhuparna Bhowmik
6132c1d903 net: core: devlink.c: Hold devlink->lock from the beginning of devlink_dpipe_table_register()
devlink_dpipe_table_find() should be called under either
rcu_read_lock() or devlink->lock. devlink_dpipe_table_register()
calls devlink_dpipe_table_find() without holding the lock
and acquires it later. Therefore hold the devlink->lock
from the beginning of devlink_dpipe_table_register().

Suggested-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-23 21:17:37 -08:00
David S. Miller
b105e8e281 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-02-21

The following pull-request contains BPF updates for your *net-next* tree.

We've added 25 non-merge commits during the last 4 day(s) which contain
a total of 33 files changed, 2433 insertions(+), 161 deletions(-).

The main changes are:

1) Allow for adding TCP listen sockets into sock_map/hash so they can be used
   with reuseport BPF programs, from Jakub Sitnicki.

2) Add a new bpf_program__set_attach_target() helper for adding libbpf support
   to specify the tracepoint/function dynamically, from Eelco Chaudron.

3) Add bpf_read_branch_records() BPF helper which helps use cases like profile
   guided optimizations, from Daniel Xu.

4) Enable bpf_perf_event_read_value() in all tracing programs, from Song Liu.

5) Relax BTF mandatory check if only used for libbpf itself e.g. to process
   BTF defined maps, from Andrii Nakryiko.

6) Move BPF selftests -mcpu compilation attribute from 'probe' to 'v3' as it has
   been observed that former fails in envs with low memlock, from Yonghong Song.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-21 15:22:45 -08:00
David S. Miller
e65ee2fb54 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflict resolution of ice_virtchnl_pf.c based upon work by
Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-21 13:39:34 -08:00
Jakub Sitnicki
035ff358f2 net: Generate reuseport group ID on group creation
Commit 736b46027e ("net: Add ID (if needed) to sock_reuseport and expose
reuseport_lock") has introduced lazy generation of reuseport group IDs that
survive group resize.

By comparing the identifier we check if BPF reuseport program is not trying
to select a socket from a BPF map that belongs to a different reuseport
group than the one the packet is for.

Because SOCKARRAY used to be the only BPF map type that can be used with
reuseport BPF, it was possible to delay the generation of reuseport group
ID until a socket from the group was inserted into BPF map for the first
time.

Now that SOCK{MAP,HASH} can be used with reuseport BPF we have two options,
either generate the reuseport ID on map update, like SOCKARRAY does, or
allocate an ID from the start when reuseport group gets created.

This patch takes the latter approach to keep sockmap free of calls into
reuseport code. This streamlines the reuseport_id access as its lifetime
now matches the longevity of reuseport object.

The cost of this simplification, however, is that we allocate reuseport IDs
for all SO_REUSEPORT users. Even those that don't use SOCKARRAY in their
setups. With the way identifiers are currently generated, we can have at
most S32_MAX reuseport groups, which hopefully is sufficient. If we ever
get close to the limit, we can switch an u64 counter like sk_cookie.

Another change is that we now always call into SOCKARRAY logic to unlink
the socket from the map when unhashing or closing the socket. Previously we
did it only when at least one socket from the group was in a BPF map.

It is worth noting that this doesn't conflict with sockmap tear-down in
case a socket is in a SOCK{MAP,HASH} and belongs to a reuseport
group. sockmap tear-down happens first:

  prot->unhash
  `- tcp_bpf_unhash
     |- tcp_bpf_remove
     |  `- while (sk_psock_link_pop(psock))
     |     `- sk_psock_unlink
     |        `- sock_map_delete_from_link
     |           `- __sock_map_delete
     |              `- sock_map_unref
     |                 `- sk_psock_put
     |                    `- sk_psock_drop
     |                       `- rcu_assign_sk_user_data(sk, NULL)
     `- inet_unhash
        `- reuseport_detach_sock
           `- bpf_sk_reuseport_detach
              `- WRITE_ONCE(sk->sk_user_data, NULL)

Suggested-by: Martin Lau <kafai@fb.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200218171023.844439-10-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
9fed9000c5 bpf: Allow selecting reuseport socket from a SOCKMAP/SOCKHASH
SOCKMAP & SOCKHASH now support storing references to listening
sockets. Nothing keeps us from using these map types a collection of
sockets to select from in BPF reuseport programs. Whitelist the map types
with the bpf_sk_select_reuseport helper.

The restriction that the socket has to be a member of a reuseport group
still applies. Sockets in SOCKMAP/SOCKHASH that don't have sk_reuseport_cb
set are not a valid target and we signal it with -EINVAL.

The main benefit from this change is that, in contrast to
REUSEPORT_SOCKARRAY, SOCK{MAP,HASH} don't impose a restriction that a
listening socket can be just one BPF map at the same time.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200218171023.844439-9-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
1d59f3bcee bpf, sockmap: Let all kernel-land lookup values in SOCKMAP/SOCKHASH
Don't require the kernel code, like BPF helpers, that needs access to
SOCK{MAP,HASH} map contents to live in net/core/sock_map.c. Expose the
lookup operation to all kernel-land.

Lookup from BPF context is not whitelisted yet. While syscalls have a
dedicated lookup handler.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-8-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
c1cdf65da0 bpf, sockmap: Return socket cookie on lookup from syscall
Tooling that populates the SOCK{MAP,HASH} with sockets from user-space
needs a way to inspect its contents. Returning the struct sock * that the
map holds to user-space is neither safe nor useful. An approach established
by REUSEPORT_SOCKARRAY is to return a socket cookie (a unique identifier)
instead.

Since socket cookies are u64 values, SOCK{MAP,HASH} need to support such a
value size for lookup to be possible. This requires special handling on
update, though. Attempts to do a lookup on a map holding u32 values will be
met with ENOSPC error.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-7-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
6e830c2f6c bpf, sockmap: Don't set up upcalls and progs for listening sockets
Now that sockmap/sockhash can hold listening sockets, when setting up the
psock we will (i) grab references to verdict/parser progs, and (2) override
socket upcalls sk_data_ready and sk_write_space.

However, since we cannot redirect to listening sockets so we don't need to
link the socket to the BPF progs. And more importantly we don't want the
listening socket to have overridden upcalls because they would get
inherited by child sockets cloned from it.

Introduce a separate initialization path for listening sockets that does
not change the upcalls and ignores the BPF progs.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-6-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
8ca30379a4 bpf, sockmap: Allow inserting listening TCP sockets into sockmap
In order for sockmap/sockhash types to become generic collections for
storing TCP sockets we need to loosen the checks during map update, while
tightening the checks in redirect helpers.

Currently sock{map,hash} require the TCP socket to be in established state,
which prevents inserting listening sockets.

Change the update pre-checks so the socket can also be in listening state.

Since it doesn't make sense to redirect with sock{map,hash} to listening
sockets, add appropriate socket state checks to BPF redirect helpers too.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-5-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
f1ff5ce2cd net, sk_msg: Clear sk_user_data pointer on clone if tagged
sk_user_data can hold a pointer to an object that is not intended to be
shared between the parent socket and the child that gets a pointer copy on
clone. This is the case when sk_user_data points at reference-counted
object, like struct sk_psock.

One way to resolve it is to tag the pointer with a no-copy flag by
repurposing its lowest bit. Based on the bit-flag value we clear the child
sk_user_data pointer after cloning the parent socket.

The no-copy flag is stored in the pointer itself as opposed to externally,
say in socket flags, to guarantee that the pointer and the flag are copied
from parent to child socket in an atomic fashion. Parent socket state is
subject to change while copying, we don't hold any locks at that time.

This approach relies on an assumption that sk_user_data holds a pointer to
an object aligned at least 2 bytes. A manual audit of existing users of
rcu_dereference_sk_user_data helper confirms our assumption.

Also, an RCU-protected sk_user_data is not likely to hold a pointer to a
char value or a pathological case of "struct { char c; }". To be safe, warn
when the flag-bit is set when setting sk_user_data to catch any future
misuses.

It is worth considering why clearing sk_user_data unconditionally is not an
option. There exist users, DRBD, NVMe, and Xen drivers being among them,
that rely on the pointer being copied when cloning the listening socket.

Potentially we could distinguish these users by checking if the listening
socket has been created in kernel-space via sock_create_kern, and hence has
sk_kern_sock flag set. However, this is not the case for NVMe and Xen
drivers, which create sockets without marking them as belonging to the
kernel.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200218171023.844439-3-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Jakub Sitnicki
b8e202d1d1 net, sk_msg: Annotate lockless access to sk_prot on clone
sk_msg and ULP frameworks override protocol callbacks pointer in
sk->sk_prot, while tcp accesses it locklessly when cloning the listening
socket, that is with neither sk_lock nor sk_callback_lock held.

Once we enable use of listening sockets with sockmap (and hence sk_msg),
there will be shared access to sk->sk_prot if socket is getting cloned
while being inserted/deleted to/from the sockmap from another CPU:

Read side:

tcp_v4_rcv
  sk = __inet_lookup_skb(...)
  tcp_check_req(sk)
    inet_csk(sk)->icsk_af_ops->syn_recv_sock
      tcp_v4_syn_recv_sock
        tcp_create_openreq_child
          inet_csk_clone_lock
            sk_clone_lock
              READ_ONCE(sk->sk_prot)

Write side:

sock_map_ops->map_update_elem
  sock_map_update_elem
    sock_map_update_common
      sock_map_link_no_progs
        tcp_bpf_init
          tcp_bpf_update_sk_prot
            sk_psock_update_proto
              WRITE_ONCE(sk->sk_prot, ops)

sock_map_ops->map_delete_elem
  sock_map_delete_elem
    __sock_map_delete
     sock_map_unref
       sk_psock_put
         sk_psock_drop
           sk_psock_restore_proto
             tcp_update_ulp
               WRITE_ONCE(sk->sk_prot, proto)

Mark the shared access with READ_ONCE/WRITE_ONCE annotations.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200218171023.844439-2-jakub@cloudflare.com
2020-02-21 22:29:45 +01:00
Julian Wiedmann
2e92a2d0e4 net: use netif_is_bridge_port() to check for IFF_BRIDGE_PORT
Trivial cleanup, so that all bridge port-specific code can be found in
one go.

CC: Johannes Berg <johannes@sipsolutions.net>
CC: Roopa Prabhu <roopa@cumulusnetworks.com>
CC: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-20 10:10:32 -08:00
Ilias Apalodimas
458de8a97f net: page_pool: API cleanup and comments
Functions starting with __ usually indicate those which are exported,
but should not be called directly. Update some of those declared in the
API and make it more readable.

page_pool_unmap_page() and page_pool_release_page() were doing
exactly the same thing calling __page_pool_clean_page().  Let's
rename __page_pool_clean_page() to page_pool_release_page() and
export it in order to show up on perf logs and get rid of
page_pool_unmap_page().

Finally rename __page_pool_put_page() to page_pool_put_page() since we
can now directly call it from drivers and rename the existing
page_pool_put_page() to page_pool_put_full_page() since they do the same
thing but the latter is trying to sync the full DMA area.

This patch also updates netsec, mvneta and stmmac drivers which use
those functions.

Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-20 10:09:25 -08:00