Commit Graph

5499 Commits

Author SHA1 Message Date
Jakub Kicinski 7ac1cc9aef devlink: don't take instance lock around eswitch mode set
Changing switch mode may want to register and unregister devlink
ports.  Therefore similarly to DEVLINK_CMD_PORT_SPLIT/UNSPLIT it
should not take the instance lock.  Drivers don't depend on existing
locking since it's a very recent addition.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-23 14:26:19 -04:00
David S. Miller 6f6e434aa2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
S390 bpf_jit.S is removed in net-next and had changes in 'net',
since that code isn't used any more take the removal.

TLS data structures split the TX and RX components in 'net-next',
put the new struct members from the bug fix in 'net' into the RX
part.

The 'net-next' tree had some reworking of how the ERSPAN code works in
the GRE tunneling code, overlapping with a one-line headroom
calculation fix in 'net'.

Overlapping changes in __sock_map_ctx_update_elem(), keep the bits
that read the prog members via READ_ONCE() into local variables
before using them.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-21 16:01:54 -04:00
Jiri Pirko 08474c1a9d devlink: introduce a helper to generate physical port names
Each driver implements physical port name generation by itself. However
as devlink has all needed info, it can easily do the job for all its
users. So implement this helper in devlink.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-19 16:30:39 -04:00
Jiri Pirko 5ec1380a21 devlink: extend attrs_set for setting port flavours
Devlink ports can have specific flavour according to the purpose of use.
This patch extend attrs_set so the driver can say which flavour port
has. Initial flavours are:
physical, cpu, dsa
User can query this to see right away what is the purpose of each port.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-19 16:30:39 -04:00
Jiri Pirko b9ffcbaf56 devlink: introduce devlink_port_attrs_set
Change existing setter for split port information into more generic
attrs setter. Alongside with that, allow to set port number and subport
number for split ports.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-19 16:30:39 -04:00
Eric Dumazet 9709020c86 sock_diag: fix use-after-free read in __sk_free
We must not call sock_diag_has_destroy_listeners(sk) on a socket
that has no reference on net structure.

BUG: KASAN: use-after-free in sock_diag_has_destroy_listeners include/linux/sock_diag.h:75 [inline]
BUG: KASAN: use-after-free in __sk_free+0x329/0x340 net/core/sock.c:1609
Read of size 8 at addr ffff88018a02e3a0 by task swapper/1/0

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.17.0-rc5+ #54
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 sock_diag_has_destroy_listeners include/linux/sock_diag.h:75 [inline]
 __sk_free+0x329/0x340 net/core/sock.c:1609
 sk_free+0x42/0x50 net/core/sock.c:1623
 sock_put include/net/sock.h:1664 [inline]
 reqsk_free include/net/request_sock.h:116 [inline]
 reqsk_put include/net/request_sock.h:124 [inline]
 inet_csk_reqsk_queue_drop_and_put net/ipv4/inet_connection_sock.c:672 [inline]
 reqsk_timer_handler+0xe27/0x10e0 net/ipv4/inet_connection_sock.c:739
 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x79e/0xc50 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x1d1/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:525 [inline]
 smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54
RSP: 0018:ffff8801d9ae7c38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 1ffff1003b35cf8a RCX: 0000000000000000
RDX: 1ffffffff11a30d0 RSI: 0000000000000001 RDI: ffffffff88d18680
RBP: ffff8801d9ae7c38 R08: ffffed003b5e46c3 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff8801d9ae7cf0 R14: ffffffff897bef20 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0xc2/0x440 arch/x86/kernel/process.c:354
 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:345
 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x395/0x560 kernel/sched/idle.c:262
 cpu_startup_entry+0x104/0x120 kernel/sched/idle.c:368
 start_secondary+0x426/0x5b0 arch/x86/kernel/smpboot.c:269
 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242

Allocated by task 4557:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554
 kmem_cache_zalloc include/linux/slab.h:691 [inline]
 net_alloc net/core/net_namespace.c:383 [inline]
 copy_net_ns+0x159/0x4c0 net/core/net_namespace.c:423
 create_new_namespaces+0x69d/0x8f0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x708/0xf90 kernel/fork.c:2408
 __do_sys_unshare kernel/fork.c:2476 [inline]
 __se_sys_unshare kernel/fork.c:2474 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:2474
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 69:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 net_free net/core/net_namespace.c:399 [inline]
 net_drop_ns.part.14+0x11a/0x130 net/core/net_namespace.c:406
 net_drop_ns net/core/net_namespace.c:405 [inline]
 cleanup_net+0x6a1/0xb20 net/core/net_namespace.c:541
 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

The buggy address belongs to the object at ffff88018a02c140
 which belongs to the cache net_namespace of size 8832
The buggy address is located 8800 bytes inside of
 8832-byte region [ffff88018a02c140, ffff88018a02e3c0)
The buggy address belongs to the page:
page:ffffea0006280b00 count:1 mapcount:0 mapping:ffff88018a02c140 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff88018a02c140 0000000000000000 0000000100000001
raw: ffffea00062a1320 ffffea0006268020 ffff8801d9bdde40 0000000000000000
page dumped because: kasan: bad access detected

Fixes: b922622ec6 ("sock_diag: don't broadcast kernel sockets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Craig Gallek <kraig@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-18 13:47:01 -04:00
Amritha Nambiar 6358d49ac2 net: Fix a bug in removing queues from XPS map
While removing queues from the XPS map, the individual CPU ID
alone was used to index the CPUs map, this should be changed to also
factor in the traffic class mapping for the CPU-to-queue lookup.

Fixes: 184c449f91 ("net: Add support for XPS with QoS via traffic classes")
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-18 12:06:22 -04:00
Daniel Borkmann 050fad7c45 bpf: fix truncated jump targets on heavy expansions
Recently during testing, I ran into the following panic:

  [  207.892422] Internal error: Accessing user space memory outside uaccess.h routines: 96000004 [#1] SMP
  [  207.901637] Modules linked in: binfmt_misc [...]
  [  207.966530] CPU: 45 PID: 2256 Comm: test_verifier Tainted: G        W         4.17.0-rc3+ #7
  [  207.974956] Hardware name: FOXCONN R2-1221R-A4/C2U4N_MB, BIOS G31FB18A 03/31/2017
  [  207.982428] pstate: 60400005 (nZCv daif +PAN -UAO)
  [  207.987214] pc : bpf_skb_load_helper_8_no_cache+0x34/0xc0
  [  207.992603] lr : 0xffff000000bdb754
  [  207.996080] sp : ffff000013703ca0
  [  207.999384] x29: ffff000013703ca0 x28: 0000000000000001
  [  208.004688] x27: 0000000000000001 x26: 0000000000000000
  [  208.009992] x25: ffff000013703ce0 x24: ffff800fb4afcb00
  [  208.015295] x23: ffff00007d2f5038 x22: ffff00007d2f5000
  [  208.020599] x21: fffffffffeff2a6f x20: 000000000000000a
  [  208.025903] x19: ffff000009578000 x18: 0000000000000a03
  [  208.031206] x17: 0000000000000000 x16: 0000000000000000
  [  208.036510] x15: 0000ffff9de83000 x14: 0000000000000000
  [  208.041813] x13: 0000000000000000 x12: 0000000000000000
  [  208.047116] x11: 0000000000000001 x10: ffff0000089e7f18
  [  208.052419] x9 : fffffffffeff2a6f x8 : 0000000000000000
  [  208.057723] x7 : 000000000000000a x6 : 00280c6160000000
  [  208.063026] x5 : 0000000000000018 x4 : 0000000000007db6
  [  208.068329] x3 : 000000000008647a x2 : 19868179b1484500
  [  208.073632] x1 : 0000000000000000 x0 : ffff000009578c08
  [  208.078938] Process test_verifier (pid: 2256, stack limit = 0x0000000049ca7974)
  [  208.086235] Call trace:
  [  208.088672]  bpf_skb_load_helper_8_no_cache+0x34/0xc0
  [  208.093713]  0xffff000000bdb754
  [  208.096845]  bpf_test_run+0x78/0xf8
  [  208.100324]  bpf_prog_test_run_skb+0x148/0x230
  [  208.104758]  sys_bpf+0x314/0x1198
  [  208.108064]  el0_svc_naked+0x30/0x34
  [  208.111632] Code: 91302260 f9400001 f9001fa1 d2800001 (29500680)
  [  208.117717] ---[ end trace 263cb8a59b5bf29f ]---

The program itself which caused this had a long jump over the whole
instruction sequence where all of the inner instructions required
heavy expansions into multiple BPF instructions. Additionally, I also
had BPF hardening enabled which requires once more rewrites of all
constant values in order to blind them. Each time we rewrite insns,
bpf_adj_branches() would need to potentially adjust branch targets
which cross the patchlet boundary to accommodate for the additional
delta. Eventually that lead to the case where the target offset could
not fit into insn->off's upper 0x7fff limit anymore where then offset
wraps around becoming negative (in s16 universe), or vice versa
depending on the jump direction.

Therefore it becomes necessary to detect and reject any such occasions
in a generic way for native eBPF and cBPF to eBPF migrations. For
the latter we can simply check bounds in the bpf_convert_filter()'s
BPF_EMIT_JMP helper macro and bail out once we surpass limits. The
bpf_patch_insn_single() for native eBPF (and cBPF to eBPF in case
of subsequent hardening) is a bit more complex in that we need to
detect such truncations before hitting the bpf_prog_realloc(). Thus
the latter is split into an extra pass to probe problematic offsets
on the original program in order to fail early. With that in place
and carefully tested I no longer hit the panic and the rewrites are
rejected properly. The above example panic I've seen on bpf-next,
though the issue itself is generic in that a guard against this issue
in bpf seems more appropriate in this case.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-17 16:05:35 -07:00
David S. Miller b9f672af14 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-05-17

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

The main changes are:

1) Provide a new BPF helper for doing a FIB and neighbor lookup
   in the kernel tables from an XDP or tc BPF program. The helper
   provides a fast-path for forwarding packets. The API supports
   IPv4, IPv6 and MPLS protocols, but currently IPv4 and IPv6 are
   implemented in this initial work, from David (Ahern).

2) Just a tiny diff but huge feature enabled for nfp driver by
   extending the BPF offload beyond a pure host processing offload.
   Offloaded XDP programs are allowed to set the RX queue index and
   thus opening the door for defining a fully programmable RSS/n-tuple
   filter replacement. Once BPF decided on a queue already, the device
   data-path will skip the conventional RSS processing completely,
   from Jakub.

3) The original sockmap implementation was array based similar to
   devmap. However unlike devmap where an ifindex has a 1:1 mapping
   into the map there are use cases with sockets that need to be
   referenced using longer keys. Hence, sockhash map is added reusing
   as much of the sockmap code as possible, from John.

4) Introduce BTF ID. The ID is allocatd through an IDR similar as
   with BPF maps and progs. It also makes BTF accessible to user
   space via BPF_BTF_GET_FD_BY_ID and adds exposure of the BTF data
   through BPF_OBJ_GET_INFO_BY_FD, from Martin.

5) Enable BPF stackmap with build_id also in NMI context. Due to the
   up_read() of current->mm->mmap_sem build_id cannot be parsed.
   This work defers the up_read() via a per-cpu irq_work so that
   at least limited support can be enabled, from Song.

6) Various BPF JIT follow-up cleanups and fixups after the LD_ABS/LD_IND
   JIT conversion as well as implementation of an optimized 32/64 bit
   immediate load in the arm64 JIT that allows to reduce the number of
   emitted instructions; in case of tested real-world programs they
   were shrinking by three percent, from Daniel.

7) Add ifindex parameter to the libbpf loader in order to enable
   BPF offload support. Right now only iproute2 can load offloaded
   BPF and this will also enable libbpf for direct integration into
   other applications, from David (Beckett).

8) Convert the plain text documentation under Documentation/bpf/ into
   RST format since this is the appropriate standard the kernel is
   moving to for all documentation. Also add an overview README.rst,
   from Jesper.

9) Add __printf verification attribute to the bpf_verifier_vlog()
   helper. Though it uses va_list we can still allow gcc to check
   the format string, from Mathieu.

10) Fix a bash reference in the BPF selftest's Makefile. The '|& ...'
    is a bash 4.0+ feature which is not guaranteed to be available
    when calling out to shell, therefore use a more portable variant,
    from Joe.

11) Fix a 64 bit division in xdp_umem_reg() by using div_u64()
    instead of relying on the gcc built-in, from Björn.

12) Fix a sock hashmap kmalloc warning reported by syzbot when an
    overly large key size is used in hashmap then causing overflows
    in htab->elem_size. Reject bogus attr->key_size early in the
    sock_hash_alloc(), from Yonghong.

13) Ensure in BPF selftests when urandom_read is being linked that
    --build-id is always enabled so that test_stacktrace_build_id[_nmi]
    won't be failing, from Alexei.

14) Add bitsperlong.h as well as errno.h uapi headers into the tools
    header infrastructure which point to one of the arch specific
    uapi headers. This was needed in order to fix a build error on
    some systems for the BPF selftests, from Sirio.

15) Allow for short options to be used in the xdp_monitor BPF sample
    code. And also a bpf.h tools uapi header sync in order to fix a
    selftest build failure. Both from Prashant.

16) More formally clarify the meaning of ID in the direct packet access
    section of the BPF documentation, from Wang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-16 22:47:11 -04:00
Paolo Abeni 32f7b44d0f sched: manipulate __QDISC_STATE_RUNNING in qdisc_run_* helpers
Currently NOLOCK qdiscs pay a measurable overhead to atomically
manipulate the __QDISC_STATE_RUNNING. Such bit is flipped twice per
packet in the uncontended scenario with packet rate below the
line rate: on packed dequeue and on the next, failing dequeue attempt.

This changeset moves the bit manipulation into the qdisc_run_{begin,end}
helpers, so that the bit is now flipped only once per packet, with
measurable performance improvement in the uncontended scenario.

This also allows simplifying the qdisc teardown code path - since
qdisc_is_running() is now effective for each qdisc type - and avoid a
possible race between qdisc_run() and dev_deactivate_many(), as now
the some_qdisc_is_busy() can properly detect NOLOCK qdiscs being busy
dequeuing packets.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-16 12:26:25 -04:00
John Fastabend 8111038444 bpf: sockmap, add hash map support
Sockmap is currently backed by an array and enforces keys to be
four bytes. This works well for many use cases and was originally
modeled after devmap which also uses four bytes keys. However,
this has become limiting in larger use cases where a hash would
be more appropriate. For example users may want to use the 5-tuple
of the socket as the lookup key.

To support this add hash support.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-15 20:41:03 +02:00
John Fastabend e5cd3abcb3 bpf: sockmap, refactor sockmap routines to work with hashmap
This patch only refactors the existing sockmap code. This will allow
much of the psock initialization code path and bpf helper codes to
work for both sockmap bpf map types that are backed by an array, the
currently supported type, and the new hash backed bpf map type
sockhash.

Most the fallout comes from three changes,

  - Pushing bpf programs into an independent structure so we
    can use it from the htab struct in the next patch.
  - Generalizing helpers to use void *key instead of the hardcoded
    u32.
  - Instead of passing map/key through the metadata we now do
    the lookup inline. This avoids storing the key in the metadata
    which will be useful when keys can be longer than 4 bytes. We
    rename the sk pointers to sk_redir at this point as well to
    avoid any confusion between the current sk pointer and the
    redirect pointer sk_redir.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-15 17:19:59 +02:00
David Ahern 87f5fc7e48 bpf: Provide helper to do forwarding lookups in kernel FIB table
Provide a helper for doing a FIB and neighbor lookup in the kernel
tables from an XDP program. The helper provides a fastpath for forwarding
packets. If the packet is a local delivery or for any reason is not a
simple lookup and forward, the packet continues up the stack.

If it is to be forwarded, the forwarding can be done directly if the
neighbor is already known. If the neighbor does not exist, the first
few packets go up the stack for neighbor resolution. Once resolved, the
xdp program provides the fast path.

On successful lookup the nexthop dmac, current device smac and egress
device index are returned.

The API supports IPv4, IPv6 and MPLS protocols, but only IPv4 and IPv6
are implemented in this patch. The API includes layer 4 parameters if
the XDP program chooses to do deep packet inspection to allow compare
against ACLs implemented as FIB rules.

Header rewrite is left to the XDP program.

The lookup takes 2 flags:
- BPF_FIB_LOOKUP_DIRECT to do a lookup that bypasses FIB rules and goes
  straight to the table associated with the device (expert setting for
  those looking to maximize throughput)

- BPF_FIB_LOOKUP_OUTPUT to do a lookup from the egress perspective.
  Default is an ingress lookup.

Initial performance numbers collected by Jesper, forwarded packets/sec:

       Full stack    XDP FIB lookup    XDP Direct lookup
IPv4   1,947,969       7,074,156          7,415,333
IPv6   1,728,000       6,165,504          7,262,720

These number are single CPU core forwarding on a Broadwell
E5-1650 v4 @ 3.60GHz.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-11 00:10:57 +02:00
Davidlohr Bueso 02786475c7 net: Update generic_xdp_needed static key to modern api
No changes in refcount semantics -- key init is false; replace

static_key_slow_inc|dec   with   static_branch_inc|dec
static_key_false          with   static_branch_unlikely

Added a '_key' suffix to generic_xdp_needed, for better self
documentation.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10 15:13:34 -04:00
Davidlohr Bueso 39e8392201 net: Update netstamp_needed static key to modern api
No changes in refcount semantics -- key init is false; replace

static_key_slow_inc|dec   with   static_branch_inc|dec
static_key_false          with   static_branch_unlikely

Added a '_key' suffix to netstamp_needed, for better self
documentation.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10 15:13:34 -04:00
Davidlohr Bueso aabf6772cc net: Update [e/in]gress_needed static key to modern api
No changes in semantics -- key init is false; replace

static_key_slow_inc|dec   with   static_branch_inc|dec
static_key_false          with   static_branch_unlikely

Added a '_key' suffix to both ingress_needed and egress_needed,
for better self documentation.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10 15:13:34 -04:00
Davidlohr Bueso a7950ae821 net/sock: Update memalloc_socks static key to modern api
No changes in refcount semantics -- key init is false; replace

static_key_slow_inc|dec   with   static_branch_inc|dec
static_key_false          with   static_branch_unlikely

Added a '_key' suffix to memalloc_socks, for better self
documentation.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-10 15:13:34 -04:00
Jakub Kicinski 0d83003256 bpf: xdp: allow offloads to store into rx_queue_index
It's fairly easy for offloaded XDP programs to select the RX queue
packets go to.  We need a way of expressing this in the software.
Allow write to the rx_queue_index field of struct xdp_md for
device-bound programs.

Skip convert_ctx_access callback entirely for offloads.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 18:04:36 +02:00
Paolo Abeni d869dea664 flow_dissector: do not rely on implicit casts
This change fixes a couple of type mismatch reported by the sparse
tool, explicitly using the requested type for the offending arguments.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-08 00:02:41 -04:00
Paolo Abeni 72a338bcc6 net: core: rework basic flow dissection helper
When the core networking needs to detect the transport offset in a given
packet and parse it explicitly, a full-blown flow_keys struct is used for
storage.
This patch introduces a smaller keys store, rework the basic flow dissect
helper to use it, and apply this new helper where possible - namely in
skb_probe_transport_header(). The used flow dissector data structures
are renamed to match more closely the new role.

The above gives ~50% performance improvement in micro benchmarking around
skb_probe_transport_header() and ~30% around eth_get_headlen(), mostly due
to the smaller memset. Small, but measurable improvement is measured also
in macro benchmarking.

v1 -> v2: use the new helper in eth_get_headlen() and skb_get_poff(),
  as per DaveM suggestion

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-08 00:02:36 -04:00
David S. Miller 01adc4851a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Minor conflict, a CHECK was placed into an if() statement
in net-next, whilst a newline was added to that CHECK
call in 'net'.  Thanks to Daniel for the merge resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-07 23:35:08 -04:00
David S. Miller a7b15ab887 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes in selftests Makefile.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-04 09:58:56 -04:00
Daniel Borkmann 4e1ec56cdc bpf: add skb_load_bytes_relative helper
This adds a small BPF helper similar to bpf_skb_load_bytes() that
is able to load relative to mac/net header offset from the skb's
linear data. Compared to bpf_skb_load_bytes(), it takes a fifth
argument namely start_header, which is either BPF_HDR_START_MAC
or BPF_HDR_START_NET. This allows for a more flexible alternative
compared to LD_ABS/LD_IND with negative offset. It's enabled for
tc BPF programs as well as sock filter program types where it's
mainly useful in reuseport programs to ease access to lower header
data.

Reference: https://lists.iovisor.org/pipermail/iovisor-dev/2017-March/000698.html
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann e0cea7ce98 bpf: implement ld_abs/ld_ind in native bpf
The main part of this work is to finally allow removal of LD_ABS
and LD_IND from the BPF core by reimplementing them through native
eBPF instead. Both LD_ABS/LD_IND were carried over from cBPF and
keeping them around in native eBPF caused way more trouble than
actually worth it. To just list some of the security issues in
the past:

  * fdfaf64e75 ("x86: bpf_jit: support negative offsets")
  * 35607b02db ("sparc: bpf_jit: fix loads from negative offsets")
  * e0ee9c1215 ("x86: bpf_jit: fix two bugs in eBPF JIT compiler")
  * 07aee94394 ("bpf, sparc: fix usage of wrong reg for load_skb_regs after call")
  * 6d59b7dbf7 ("bpf, s390x: do not reload skb pointers in non-skb context")
  * 87338c8e2c ("bpf, ppc64: do not reload skb pointers in non-skb context")

For programs in native eBPF, LD_ABS/LD_IND are pretty much legacy
these days due to their limitations and more efficient/flexible
alternatives that have been developed over time such as direct
packet access. LD_ABS/LD_IND only cover 1/2/4 byte loads into a
register, the load happens in host endianness and its exception
handling can yield unexpected behavior. The latter is explained
in depth in f6b1b3bf0d ("bpf: fix subprog verifier bypass by
div/mod by 0 exception") with similar cases of exceptions we had.
In native eBPF more recent program types will disable LD_ABS/LD_IND
altogether through may_access_skb() in verifier, and given the
limitations in terms of exception handling, it's also disabled
in programs that use BPF to BPF calls.

In terms of cBPF, the LD_ABS/LD_IND is used in networking programs
to access packet data. It is not used in seccomp-BPF but programs
that use it for socket filtering or reuseport for demuxing with
cBPF. This is mostly relevant for applications that have not yet
migrated to native eBPF.

The main complexity and source of bugs in LD_ABS/LD_IND is coming
from their implementation in the various JITs. Most of them keep
the model around from cBPF times by implementing a fastpath written
in asm. They use typically two from the BPF program hidden CPU
registers for caching the skb's headlen (skb->len - skb->data_len)
and skb->data. Throughout the JIT phase this requires to keep track
whether LD_ABS/LD_IND are used and if so, the two registers need
to be recached each time a BPF helper would change the underlying
packet data in native eBPF case. At least in eBPF case, available
CPU registers are rare and the additional exit path out of the
asm written JIT helper makes it also inflexible since not all
parts of the JITer are in control from plain C. A LD_ABS/LD_IND
implementation in eBPF therefore allows to significantly reduce
the complexity in JITs with comparable performance results for
them, e.g.:

test_bpf             tcpdump port 22             tcpdump complex
x64      - before    15 21 10                    14 19  18
         - after      7 10 10                     7 10  15
arm64    - before    40 91 92                    40 91 151
         - after     51 64 73                    51 62 113

For cBPF we now track any usage of LD_ABS/LD_IND in bpf_convert_filter()
and cache the skb's headlen and data in the cBPF prologue. The
BPF_REG_TMP gets remapped from R8 to R2 since it's mainly just
used as a local temporary variable. This allows to shrink the
image on x86_64 also for seccomp programs slightly since mapping
to %rsi is not an ereg. In callee-saved R8 and R9 we now track
skb data and headlen, respectively. For normal prologue emission
in the JITs this does not add any extra instructions since R8, R9
are pushed to stack in any case from eBPF side. cBPF uses the
convert_bpf_ld_abs() emitter which probes the fast path inline
already and falls back to bpf_skb_load_helper_{8,16,32}() helper
relying on the cached skb data and headlen as well. R8 and R9
never need to be reloaded due to bpf_helper_changes_pkt_data()
since all skb access in cBPF is read-only. Then, for the case
of native eBPF, we use the bpf_gen_ld_abs() emitter, which calls
the bpf_skb_load_helper_{8,16,32}_no_cache() helper unconditionally,
does neither cache skb data and headlen nor has an inlined fast
path. The reason for the latter is that native eBPF does not have
any extra registers available anyway, but even if there were, it
avoids any reload of skb data and headlen in the first place.
Additionally, for the negative offsets, we provide an alternative
bpf_skb_load_bytes_relative() helper in eBPF which operates
similarly as bpf_skb_load_bytes() and allows for more flexibility.
Tested myself on x64, arm64, s390x, from Sandipan on ppc64.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann 93731ef086 bpf: migrate ebpf ld_abs/ld_ind tests to test_verifier
Remove all eBPF tests involving LD_ABS/LD_IND from test_bpf.ko. Reason
is that the eBPF tests from test_bpf module do not go via BPF verifier
and therefore any instruction rewrites from verifier cannot take place.

Therefore, move them into test_verifier which runs out of user space,
so that verfier can rewrite LD_ABS/LD_IND internally in upcoming patches.
It will have the same effect since runtime tests are also performed from
there. This also allows to finally unexport bpf_skb_vlan_{push,pop}_proto
and keep it internal to core kernel.

Additionally, also add further cBPF LD_ABS/LD_IND test coverage into
test_bpf.ko suite.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann b390134c24 bpf: prefix cbpf internal helpers with bpf_
No change in functionality, just remove the '__' prefix and replace it
with a 'bpf_' prefix instead. We later on add a couple of more helpers
for cBPF and keeping the scheme with '__' is suboptimal there.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Magnus Karlsson 865b03f211 dev: packet: make packet_direct_xmit a common function
The new dev_direct_xmit will be used by AF_XDP in later commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel 02671e23e7 xsk: wire up XDP_SKB side of AF_XDP
This commit wires up the xskmap to XDP_SKB layer.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel 1b1a251c83 xsk: wire up XDP_DRV side of AF_XDP
This commit wires up the xskmap to XDP_DRV layer.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel c497176cb2 xsk: add Rx receive functions and poll support
Here the actual receive functions of AF_XDP are implemented, that in a
later commit, will be called from the XDP layers.

There's one set of functions for the XDP_DRV side and another for
XDP_SKB (generic).

A new XDP API, xdp_return_buff, is also introduced.

Adding xdp_return_buff, which is analogous to xdp_return_frame, but
acts upon an struct xdp_buff. The API will be used by AF_XDP in future
commits.

Support for the poll syscall is also implemented.

v2: xskq_validate_id did not update cons_tail.
    The entries variable was calculated twice in xskq_nb_avail.
    Squashed xdp_return_buff commit.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel 68e8b849b2 net: initial AF_XDP skeleton
Buildable skeleton of AF_XDP without any functionality. Just what it
takes to register a new address family.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Florian Fainelli e283de3a4f net: core: Inline netdev_features_size_check()
We do not require this inline function to be used in multiple different
locations, just inline it where it gets used in register_netdevice().

Suggested-by: David Miller <davem@davemloft.net>
Suggested-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 14:24:19 -04:00
Wenwen Wang d656fe49e3 ethtool: fix a potential missing-check bug
In ethtool_get_rxnfc(), the object "info" is firstly copied from
user-space. If the FLOW_RSS flag is set in the member field flow_type of
"info" (and cmd is ETHTOOL_GRXFH), info needs to be copied again from
user-space because FLOW_RSS is newer and has new definition, as mentioned
in the comment. However, given that the user data resides in user-space, a
malicious user can race to change the data after the first copy. By doing
so, the user can inject inconsistent data. For example, in the second
copy, the FLOW_RSS flag could be cleared in the field flow_type of "info".
In the following execution, "info" will be used in the function
ops->get_rxnfc(). Such inconsistent data can potentially lead to unexpected
information leakage since ops->get_rxnfc() will prepare various types of
data according to flow_type, and the prepared data will be eventually
copied to user-space. This inconsistent data may also cause undefined
behaviors based on how ops->get_rxnfc() is implemented.

This patch simply re-verifies the flow_type field of "info" after the
second copy. If the value is not as expected, an error code will be
returned.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 14:18:47 -04:00
Ilya Lesokhin 2342a8512a net: Add TLS TX offload features
This patch adds a netdev feature to configure TLS TX offloads.

Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 09:42:47 -04:00
Ilya Lesokhin ebf4e808fa net: Add Software fallback infrastructure for socket dependent offloads
With socket dependent offloads we rely on the netdev to transform
the transmitted packets before sending them to the wire.
When a packet from an offloaded socket is rerouted to a different
device we need to detect it and do the transformation in software.

Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 09:42:46 -04:00
Ilya Lesokhin 08303c1895 net: Rename and export copy_skb_header
copy_skb_header is renamed to skb_copy_header and
exported. Exposing this function give more flexibility
in copying SKBs.
skb_copy and skb_copy_expand do not give enough control
over which parts are copied.

Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 09:42:46 -04:00
Florian Fainelli 3ac305c386 net: core: Assert the size of netdev_featres_t
We have about 53 netdev_features_t bits defined and counting, add a
build time check to catch when an u64 type will not be enough and we
will have to convert that to a bitmap. This is done in
register_netdevice() for convenience.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-29 22:50:36 -04:00
Alexander Duyck 1b837d489e net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash
I am dropping the export of __skb_tx_hash as after my patches nobody is
using it outside of the net/core/dev.c file. In addition I am renaming and
repurposing it to just be a static declaration of skb_tx_hash since that
was the only user for it at this point. By doing this the compiler can
inline it into __netdev_pick_tx as that will improve performance.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-29 22:01:33 -04:00
Kirill Tkhai 3f5ecd8a90 net: Fix coccinelle warning
kbuild test robot says:

  >coccinelle warnings: (new ones prefixed by >>)
  >>> net/core/dev.c:1588:2-3: Unneeded semicolon

So, let's remove it.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:53:14 -04:00
Florian Fainelli 9994338227 net: Allow network devices to have PHY statistics
Add a new callback: get_ethtool_phy_stats() which allows network device
drivers not making use of the PHY library to return PHY statistics.
Update ethtool_get_phy_stats(), __ethtool_get_sset_count() and
__ethtool_get_strings() accordingly to interogate the network device
about ETH_SS_PHY_STATS.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:02 -04:00
Florian Fainelli c59530d0d5 net: Move PHY statistics code into PHY library helpers
In order to make it possible for network device drivers that do not
necessarily have a phy_device attached, but still report PHY statistics,
have a preliminary refactoring consisting in creating helper functions
that encapsulate the PHY device driver knowledge within PHYLIB.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:02 -04:00
David S. Miller 79741a38b4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-04-27

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

The main changes are:

1) Add extensive BPF helper description into include/uapi/linux/bpf.h
   and a new script bpf_helpers_doc.py which allows for generating a
   man page out of it. Thus, every helper in BPF now comes with proper
   function signature, detailed description and return code explanation,
   from Quentin.

2) Migrate the BPF collect metadata tunnel tests from BPF samples over
   to the BPF selftests and further extend them with v6 vxlan, geneve
   and ipip tests, simplify the ipip tests, improve documentation and
   convert to bpf_ntoh*() / bpf_hton*() api, from William.

3) Currently, helpers that expect ARG_PTR_TO_MAP_{KEY,VALUE} can only
   access stack and packet memory. Extend this to allow such helpers
   to also use map values, which enabled use cases where value from
   a first lookup can be directly used as a key for a second lookup,
   from Paul.

4) Add a new helper bpf_skb_get_xfrm_state() for tc BPF programs in
   order to retrieve XFRM state information containing SPI, peer
   address and reqid values, from Eyal.

5) Various optimizations in nfp driver's BPF JIT in order to turn ADD
   and SUB instructions with negative immediate into the opposite
   operation with a positive immediate such that nfp can better fit
   small immediates into instructions. Savings in instruction count
   up to 4% have been observed, from Jakub.

6) Add the BPF prog's gpl_compatible flag to struct bpf_prog_info
   and add support for dumping this through bpftool, from Jiri.

7) Move the BPF sockmap samples over into BPF selftests instead since
   sockmap was rather a series of tests than sample anyway and this way
   this can be run from automated bots, from John.

8) Follow-up fix for bpf_adjust_tail() helper in order to make it work
   with generic XDP, from Nikita.

9) Some follow-up cleanups to BTF, namely, removing unused defines from
   BTF uapi header and renaming 'name' struct btf_* members into name_off
   to make it more clear they are offsets into string section, from Martin.

10) Remove test_sock_addr from TEST_GEN_PROGS in BPF selftests since
    not run directly but invoked from test_sock_addr.sh, from Yonghong.

11) Remove redundant ret assignment in sample BPF loader, from Wang.

12) Add couple of missing files to BPF selftest's gitignore, from Anders.

There are two trivial merge conflicts while pulling:

  1) Remove samples/sockmap/Makefile since all sockmap tests have been
     moved to selftests.
  2) Add both hunks from tools/testing/selftests/bpf/.gitignore to the
     file since git should ignore all of them.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 21:19:50 -04:00
Nikita V. Shirokov f761312023 bpf: fix xdp_generic for bpf_adjust_tail usecase
When bpf_adjust_tail was introduced for generic xdp, it changed skb's tail
pointer, so it was pointing to the new "end of the packet". However skb's
len field wasn't properly modified, so on the wire ethernet frame had
original (or even bigger, if adjust_head was used) size. This diff is
fixing this.

Fixes: 198d83bb3 (" bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail")
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:56:40 +02:00
Willem de Bruijn 83aa025f53 udp: add gso support to virtual devices
Virtual devices such as tunnels and bonding can handle large packets.
Only segment packets when reaching a physical or loopback device.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 15:09:12 -04:00
Willem de Bruijn ee80d1ebe5 udp: add udp gso
Implement generic segmentation offload support for udp datagrams. A
follow-up patch adds support to the protocol stack to generate such
packets.

UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits
a large payload into a number of discrete UDP datagrams.

The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it
from UFO (SKB_UDP_GSO).

IPPROTO_UDPLITE is excluded, as that protocol has no gso handler
registered.

[ Export __udp_gso_segment for ipv6. -DaveM ]

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 15:07:42 -04:00
David S. Miller a9537c937c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merging net into net-next to help the bpf folks avoid
some really ugly merge conflicts.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25 23:04:22 -04:00
David Ahern c77bbc648f net: rules: Move l3mdev attribute validation to a helper
Move the check on FRA_L3MDEV attribute to helper to improve the
readability of fib_nl2rule. Update the extack messages to be
clear when the configuration option is disabled versus an invalid
value has been passed.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25 13:26:12 -04:00
Roopa Prabhu 9ce33e4653 neighbour: support for NTF_EXT_LEARNED flag
This patch extends NTF_EXT_LEARNED support to the neighbour system.
Example use-case: An Ethernet VPN implementation (eg in FRR routing suite)
can use this flag to add dynamic reachable external neigh entires
learned via control plane. The use of neigh NTF_EXT_LEARNED in this
patch is consistent with its use with bridge and vxlan fdb entries.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25 13:19:59 -04:00
William Tu 5540fbf438 bpf: clear the ip_tunnel_info.
The percpu metadata_dst might carry the stale ip_tunnel_info
and cause incorrect behavior.  When mixing tests using ipv4/ipv6
bpf vxlan and geneve tunnel, the ipv6 tunnel info incorrectly uses
ipv4's src ip addr as its ipv6 src address, because the previous
tunnel info does not clean up.  The patch zeros the fields in
ip_tunnel_info.

Signed-off-by: William Tu <u9012063@gmail.com>
Reported-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-25 09:51:54 +02:00
Eyal Birger 12bed760a7 bpf: add helper for getting xfrm states
This commit introduces a helper which allows fetching xfrm state
parameters by eBPF programs attached to TC.

Prototype:
bpf_skb_get_xfrm_state(skb, index, xfrm_state, size, flags)

skb: pointer to skb
index: the index in the skb xfrm_state secpath array
xfrm_state: pointer to 'struct bpf_xfrm_state'
size: size of 'struct bpf_xfrm_state'
flags: reserved for future extensions

The helper returns 0 on success. Non zero if no xfrm state at the index
is found - or non exists at all.

struct bpf_xfrm_state currently includes the SPI, peer IPv4/IPv6
address and the reqid; it can be further extended by adding elements to
its end - indicating the populated fields by the 'size' argument -
keeping backwards compatibility.

Typical usage:

struct bpf_xfrm_state x = {};
bpf_skb_get_xfrm_state(skb, 0, &x, sizeof(x), 0);
...

Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 22:26:58 +02:00