Commit graph

783672 commits

Author SHA1 Message Date
Magnus Karlsson
661b8d1b0e net: add umem reference in netdev{_rx}_queue
These references to the umem will be used to store information
on what kind of AF_XDP umem that is bound to a queue id, if any.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-05 09:31:00 +02:00
Konrad Djimeli
7ccc4f1887 bpf: typo fix in Documentation/networking/af_xdp.rst
Fix a simple typo: Completetion -> Completion

Signed-off-by: Konrad Djimeli <kdjimeli@igalia.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-05 00:11:24 +02:00
Bo YU
20cdeb5408 bpf, tracex3_user: erase "ARRAY_SIZE" redefined
There is a warning when compiling bpf sample programs in sample/bpf:

  make -C /home/foo/bpf/samples/bpf/../../tools/lib/bpf/ RM='rm -rf' LDFLAGS= srctree=/home/foo/bpf/samples/bpf/../../ O=
    HOSTCC  /home/foo/bpf/samples/bpf/tracex3_user.o
  /home/foo/bpf/samples/bpf/tracex3_user.c:20:0: warning: "ARRAY_SIZE" redefined
   #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))

  In file included from /home/foo/bpf/samples/bpf/tracex3_user.c:18:0:
  ./tools/testing/selftests/bpf/bpf_util.h:48:0: note: this is the location of the previous definition
   # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

Signed-off-by: Bo YU <tsu.yubo@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:31:57 +02:00
Daniel Borkmann
fc1dc76651 Merge branch 'bpf-libbpf-consistent-iface'
Andrey Ignatov says:

====================
This patch set renames a few interfaces in libbpf, mostly netlink related,
so that all symbols provided by the library have only three possible
prefixes:

% nm -D tools/lib/bpf/libbpf.so  | \
    awk '$2 == "T" {sub(/[_\(].*/, "", $3); if ($3) print $3}' | \
    sort | \
    uniq -c
     91 bpf
      8 btf
     14 libbpf

libbpf is used more and more outside kernel tree. That means the library
should follow good practices in library design and implementation to
play well with third party code that uses it.

One of such practices is to have a common prefix (or a few) for every
interface, function or data structure, library provides. It helps to
avoid name conflicts with other libraries and keeps API/ABI consistent.

Inconsistent names in libbpf already cause problems in real life. E.g.
an application can't use both libbpf and libnl due to conflicting
symbols (specifically nla_parse, nla_parse_nested and a few others).

Some of problematic global symbols are not part of ABI and can be
restricted from export with either visibility attribute/pragma or export
map (what is useful by itself and can be done in addition). That won't
solve the problem for those that are part of ABI though. Also export
restrictions would help only in DSO case. If third party application links
libbpf statically it won't help, and people do it (e.g. Facebook links
most of libraries statically, including libbpf).

libbpf already uses the following prefixes for its interfaces:
* bpf_ for bpf system call wrappers, program/map/elf-object
  abstractions and a few other things;
* btf_ for BTF related API;
* libbpf_ for everything else.

The patch adds libbpf_ prefix to interfaces that use none of mentioned
above prefixes and don't fit well into the first two categories.

Long term benefits of having common prefix should outweigh possible
inconvenience of changing API for those functions now.

Patches 2-4 add libbpf_ prefix to libbpf interfaces: separate patch per
header. Other patches are simple improvements in API.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:18 +02:00
Andrey Ignatov
e5b0863c20 libbpf: Use __u32 instead of u32 in bpf_program__load
Make bpf_program__load consistent with other interfaces: use __u32
instead of u32. That in turn fixes build of samples:

In file included from ./samples/bpf/trace_output_user.c:21:0:
./tools/lib/bpf/libbpf.h:132:9: error: unknown type name ‘u32’
         u32 kern_version);
         ^

Fixes: commit 29cd77f416 ("libbpf: Support loading individual progs")
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:16 +02:00
Andrey Ignatov
eff8190880 libbpf: Make include guards consistent
Rename include guards to have consistent names "__LIBBPF_<header_name>".

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:16 +02:00
Andrey Ignatov
24d6a80842 libbpf: Consistent prefixes for interfaces in str_error.h.
libbpf is used more and more outside kernel tree. That means the library
should follow good practices in library design and implementation to
play well with third party code that uses it.

One of such practices is to have a common prefix (or a few) for every
interface, function or data structure, library provides. I helps to
avoid name conflicts with other libraries and keeps API consistent.

Inconsistent names in libbpf already cause problems in real life. E.g.
an application can't use both libbpf and libnl due to conflicting
symbols.

Having common prefix will help to fix current and avoid future problems.

libbpf already uses the following prefixes for its interfaces:
* bpf_ for bpf system call wrappers, program/map/elf-object
  abstractions and a few other things;
* btf_ for BTF related API;
* libbpf_ for everything else.

The patch renames function in str_error.h to have libbpf_ prefix since it
misses one and doesn't fit well into the first two categories.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:16 +02:00
Andrey Ignatov
f04bc8a436 libbpf: Consistent prefixes for interfaces in nlattr.h.
libbpf is used more and more outside kernel tree. That means the library
should follow good practices in library design and implementation to
play well with third party code that uses it.

One of such practices is to have a common prefix (or a few) for every
interface, function or data structure, library provides. I helps to
avoid name conflicts with other libraries and keeps API consistent.

Inconsistent names in libbpf already cause problems in real life. E.g.
an application can't use both libbpf and libnl due to conflicting
symbols.

Having common prefix will help to fix current and avoid future problems.

libbpf already uses the following prefixes for its interfaces:
* bpf_ for bpf system call wrappers, program/map/elf-object
  abstractions and a few other things;
* btf_ for BTF related API;
* libbpf_ for everything else.

The patch adds libbpf_ prefix to interfaces in nlattr.h that use none of
mentioned above prefixes and doesn't fit well into the first two
categories.

Since affected part of API is used in bpftool, the patch applies
corresponding change to bpftool as well. Having it in a separate patch
will cause a state of tree where bpftool is broken what may not be a
good idea.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:16 +02:00
Andrey Ignatov
aae5778010 libbpf: Consistent prefixes for interfaces in libbpf.h.
libbpf is used more and more outside kernel tree. That means the library
should follow good practices in library design and implementation to
play well with third party code that uses it.

One of such practices is to have a common prefix (or a few) for every
interface, function or data structure, library provides. I helps to
avoid name conflicts with other libraries and keeps API consistent.

Inconsistent names in libbpf already cause problems in real life. E.g.
an application can't use both libbpf and libnl due to conflicting
symbols.

Having common prefix will help to fix current and avoid future problems.

libbpf already uses the following prefixes for its interfaces:
* bpf_ for bpf system call wrappers, program/map/elf-object
  abstractions and a few other things;
* btf_ for BTF related API;
* libbpf_ for everything else.

The patch adds libbpf_ prefix to functions and typedef in libbpf.h that
use none of mentioned above prefixes and doesn't fit well into the first
two categories.

Since affected part of API is used in bpftool, the patch applies
corresponding change to bpftool as well. Having it in a separate patch
will cause a state of tree where bpftool is broken what may not be a
good idea.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:16 +02:00
Andrey Ignatov
434fe9d4b4 libbpf: Move __dump_nlmsg_t from API to implementation
This typedef is used only by implementation in netlink.c. Nothing uses
it in public API. Move it to netlink.c.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 16:04:15 +02:00
Joe Stringer
d71019b54b net: core: Fix build with CONFIG_IPV6=m
Stephen Rothwell reports the following link failure with IPv6 as module:

  x86_64-linux-gnu-ld: net/core/filter.o: in function `sk_lookup':
  (.text+0x19219): undefined reference to `__udp6_lib_lookup'

Fix the build by only enabling the IPv6 socket lookup if IPv6 support is
compiled into the kernel.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-04 10:32:56 +02:00
Daniel Borkmann
33d9a7fd67 Merge branch 'bpf-sk-lookup'
Joe Stringer says:

====================
This series proposes a new helper for the BPF API which allows BPF programs to
perform lookups for sockets in a network namespace. This would allow programs
to determine early on in processing whether the stack is expecting to receive
the packet, and perform some action (eg drop, forward somewhere) based on this
information.

The series is structured roughly into:
* Misc refactor
* Add the socket pointer type
* Add reference tracking to ensure that socket references are freed
* Extend the BPF API to add sk_lookup_xxx() / sk_release() functions
* Add tests/documentation

The helper proposed in this series includes a parameter for a tuple which must
be filled in by the caller to determine the socket to look up. The simplest
case would be filling with the contents of the packet, ie mapping the packet's
5-tuple into the parameter. In common cases, it may alternatively be useful to
reverse the direction of the tuple and perform a lookup, to find the socket
that initiates this connection; and if the BPF program ever performs a form of
IP address translation, it may further be useful to be able to look up
arbitrary tuples that are not based upon the packet, but instead based on state
held in BPF maps or hardcoded in the BPF program.

Currently, access into the socket's fields are limited to those which are
otherwise already accessible, and are restricted to read-only access.

Changes since v3:
* New patch: "bpf: Reuse canonical string formatter for ctx errs"
* Add PTR_TO_SOCKET to is_ctx_reg().
* Add a few new checks to prevent mixing of socket/non-socket pointers.
* Swap order of checks in sock_filter_is_valid_access().
* Prefix register spill macros with "bpf_".
* Add acks from previous round
* Rebase

Changes since v2:
* New patch: "selftests/bpf: Generalize dummy program types".
  This enables adding verifier tests for socket lookup with tail calls.
* Define the semantics of the new helpers more clearly in uAPI header.
* Fix release of caller_net when netns is not specified.
* Use skb->sk to find caller net when skb->dev is unavailable.
* Fix build with !CONFIG_NET.
* Replace ptr_id defensive coding when releasing reference state with an
  internal error (-EFAULT).
* Remove flags argument to sk_release().
* Add several new assembly tests suggested by Daniel.
* Add a few new C tests.
* Fix typo in verifier error message.

Changes since v1:
* Limit netns_id field to 32 bits
* Reuse reg_type_mismatch() in more places
* Reduce the number of passes at convert_ctx_access()
* Replace ptr_id defensive coding when releasing reference state with an
  internal error (-EFAULT)
* Rework 'struct bpf_sock_tuple' to allow passing a packet pointer
* Allow direct packet access from helper
* Fix compile error with CONFIG_IPV6 enabled
* Improve commit messages

Changes since RFC:
* Split up sk_lookup() into sk_lookup_tcp(), sk_lookup_udp().
* Only take references on the socket when necessary.
  * Make sk_release() only free the socket reference in this case.
* Fix some runtime reference leaks:
  * Disallow BPF_LD_[ABS|IND] instructions while holding a reference.
  * Disallow bpf_tail_call() while holding a reference.
* Prevent the same instruction being used for reference and other
  pointer type.
* Simplify locating copies of a reference during helper calls by caching
  the pointer id from the caller.
* Fix kbuild compilation warnings with particular configs.
* Improve code comments describing the new verifier pieces.
* Tested by Nitin
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:50 +02:00
Joe Stringer
a610b665ec Documentation: Describe bpf reference tracking
Document the new pointer types in the verifier and how the pointer ID
tracking works to ensure that references which are taken are later
released.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:48 +02:00
Joe Stringer
de375f4e91 selftests/bpf: Add C tests for reference tracking
Add some tests that demonstrate and test the balanced lookup/free
nature of socket lookup. Section names that start with "fail" represent
programs that are expected to fail verification; all others should
succeed.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:48 +02:00
Joe Stringer
29cd77f416 libbpf: Support loading individual progs
Allow the individual program load to be invoked. This will help with
testing, where a single ELF may contain several sections, some of which
denote subprograms that are expected to fail verification, along with
some which are expected to pass verification. By allowing programs to be
iterated and individually loaded, each program can be independently
checked against its expected verification result.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:48 +02:00
Joe Stringer
b584ab8840 selftests/bpf: Add tests for reference tracking
reference tracking: leak potential reference
reference tracking: leak potential reference on stack
reference tracking: leak potential reference on stack 2
reference tracking: zero potential reference
reference tracking: copy and zero potential references
reference tracking: release reference without check
reference tracking: release reference
reference tracking: release reference twice
reference tracking: release reference twice inside branch
reference tracking: alloc, check, free in one subbranch
reference tracking: alloc, check, free in both subbranches
reference tracking in call: free reference in subprog
reference tracking in call: free reference in subprog and outside
reference tracking in call: alloc & leak reference in subprog
reference tracking in call: alloc in subprog, release outside
reference tracking in call: sk_ptr leak into caller stack
reference tracking in call: sk_ptr spill into caller stack
reference tracking: allow LD_ABS
reference tracking: forbid LD_ABS while holding reference
reference tracking: allow LD_IND
reference tracking: forbid LD_IND while holding reference
reference tracking: check reference or tail call
reference tracking: release reference then tail call
reference tracking: leak possible reference over tail call
reference tracking: leak checked reference over tail call
reference tracking: mangle and release sock_or_null
reference tracking: mangle and release sock
reference tracking: access member
reference tracking: write to member
reference tracking: invalid 64-bit access of member
reference tracking: access after release
reference tracking: direct access for lookup
unpriv: spill/fill of different pointers stx - ctx and sock
unpriv: spill/fill of different pointers stx - leak sock
unpriv: spill/fill of different pointers stx - sock and ctx (read)
unpriv: spill/fill of different pointers stx - sock and ctx (write)

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:48 +02:00
Joe Stringer
0c586079f8 selftests/bpf: Generalize dummy program types
Don't hardcode the dummy program types to SOCKET_FILTER type, as this
prevents testing bpf_tail_call in conjunction with other program types.
Instead, use the program type specified in the test case.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:48 +02:00
Joe Stringer
6acc9b432e bpf: Add helper to retrieve socket in BPF
This patch adds new BPF helper functions, bpf_sk_lookup_tcp() and
bpf_sk_lookup_udp() which allows BPF programs to find out if there is a
socket listening on this host, and returns a socket pointer which the
BPF program can then access to determine, for instance, whether to
forward or drop traffic. bpf_sk_lookup_xxx() may take a reference on the
socket, so when a BPF program makes use of this function, it must
subsequently pass the returned pointer into the newly added sk_release()
to return the reference.

By way of example, the following pseudocode would filter inbound
connections at XDP if there is no corresponding service listening for
the traffic:

  struct bpf_sock_tuple tuple;
  struct bpf_sock_ops *sk;

  populate_tuple(ctx, &tuple); // Extract the 5tuple from the packet
  sk = bpf_sk_lookup_tcp(ctx, &tuple, sizeof tuple, netns, 0);
  if (!sk) {
    // Couldn't find a socket listening for this traffic. Drop.
    return TC_ACT_SHOT;
  }
  bpf_sk_release(sk, 0);
  return TC_ACT_OK;

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
fd978bf7fd bpf: Add reference tracking to verifier
Allow helper functions to acquire a reference and return it into a
register. Specific pointer types such as the PTR_TO_SOCKET will
implicitly represent such a reference. The verifier must ensure that
these references are released exactly once in each path through the
program.

To achieve this, this commit assigns an id to the pointer and tracks it
in the 'bpf_func_state', then when the function or program exits,
verifies that all of the acquired references have been freed. When the
pointer is passed to a function that frees the reference, it is removed
from the 'bpf_func_state` and all existing copies of the pointer in
registers are marked invalid.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
84dbf35073 bpf: Macrofy stack state copy
An upcoming commit will need very similar copy/realloc boilerplate, so
refactor the existing stack copy/realloc functions into macros to
simplify it.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
c64b798328 bpf: Add PTR_TO_SOCKET verifier type
Teach the verifier a little bit about a new type of pointer, a
PTR_TO_SOCKET. This pointer type is accessed from BPF through the
'struct bpf_sock' structure.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
840b9615d6 bpf: Generalize ptr_or_null regs check
This check will be reused by an upcoming commit for conditional jump
checks for sockets. Refactor it a bit to simplify the later commit.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
9d2be44a7f bpf: Reuse canonical string formatter for ctx errs
The array "reg_type_str" provides canonical formatting of register
types, however a couple of places would previously check whether a
register represented the context and write the name "context" directly.
An upcoming commit will add another pointer type to these statements, so
to provide more accurate error messages in the verifier, update these
error messages to use "reg_type_str" instead.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
aad2eeaf46 bpf: Simplify ptr_min_max_vals adjustment
An upcoming commit will add another two pointer types that need very
similar behaviour, so generalise this function now.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:47 +02:00
Joe Stringer
f3709f69b7 bpf: Add iterator for spilled registers
Add this iterator for spilled registers, it concentrates the details of
how to get the current frame's spilled registers into a single macro
while clarifying the intention of the code which is calling the macro.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-03 02:53:46 +02:00
Daniel Borkmann
940656fb3f Merge branch 'bpf-big-map-entries'
Jakub Kicinski says:

====================
This series makes the control message parsing for interacting
with BPF maps more flexible.  Up until now we had a hard limit
in the ABI for key and value size to be 64B at most.  Using
TLV capability allows us to support large map entries.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02 14:40:00 +02:00
Jakub Kicinski
0c9864c05f nfp: bpf: allow control message sizing for map ops
In current ABI the size of the messages carrying map elements was
statically defined to at most 16 words of key and 16 words of value
(NFP word is 4 bytes).  We should not make this assumption and use
the max key and value sizes from the BPF capability instead.

To make sure old kernels don't get surprised with larger (or smaller)
messages bump the FW ABI version to 3 when key/value size is different
than 16 words.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02 14:39:59 +02:00
Jakub Kicinski
9bbdd41b8a nfp: allow apps to request larger MTU on control vNIC
Some apps may want to have higher MTU on the control vNIC/queue.
Allow them to set the requested MTU at init time.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02 14:39:59 +02:00
Jakub Kicinski
28264eb227 nfp: bpf: parse global BPF ABI version capability
Up until now we only had per-vNIC BPF ABI version capabilities,
which are slightly awkward to use because bulk of the resources
and configuration does not relate to any particular vNIC.  Add
a new capability for global ABI version and check the per-vNIC
version are equal to it.  Assume the ABI version 2 if no explicit
version capability is present.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02 14:39:58 +02:00
Daniel Borkmann
cb86d0f878 Merge branch 'bpf-per-cpu-cgroup-storage'
Roman Gushchin says:

====================
This patchset implements per-cpu cgroup local storage and provides
an example how per-cpu and shared cgroup local storage can be used
for efficient accounting of network traffic.

v4->v3:
  1) incorporated Alexei's feedback

v3->v2:
  1) incorporated Song's feedback
  2) rebased on top of current bpf-next

v2->v1:
  1) added a selftest implementing network counters
  2) added a missing free() in cgroup local storage selftest
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:35 +02:00
Roman Gushchin
371e4fcc9d selftests/bpf: cgroup local storage-based network counters
This commit adds a bpf kselftest, which demonstrates how percpu
and shared cgroup local storage can be used for efficient lookup-free
network accounting.

Cgroup local storage provides generic memory area with a very efficient
lookup free access. To avoid expensive atomic operations for each
packet, per-cpu cgroup local storage is used. Each packet is initially
charged to a per-cpu counter, and only if the counter reaches certain
value (32 in this case), the charge is moved into the global atomic
counter. This allows to amortize atomic operations, keeping reasonable
accuracy.

The test also implements a naive network traffic throttling, mostly to
demonstrate the possibility of bpf cgroup--based network bandwidth
control.

Expected output:
  ./test_netcnt
  test_netcnt:PASS

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
5fcbd29b37 samples/bpf: extend test_cgrp2_attach2 test to use per-cpu cgroup storage
This commit extends the test_cgrp2_attach2 test to cover per-cpu
cgroup storage. Bpf program will use shared and per-cpu cgroup
storages simultaneously, so a better coverage of corresponding
core code will be achieved.

Expected output:
  $ ./test_cgrp2_attach2
  Attached DROP prog. This ping in cgroup /foo should fail...
  ping: sendmsg: Operation not permitted
  Attached DROP prog. This ping in cgroup /foo/bar should fail...
  ping: sendmsg: Operation not permitted
  Attached PASS prog. This ping in cgroup /foo/bar should pass...
  Detached PASS from /foo/bar while DROP is attached to /foo.
  This ping in cgroup /foo/bar should fail...
  ping: sendmsg: Operation not permitted
  Attached PASS from /foo/bar and detached DROP from /foo.
  This ping in cgroup /foo/bar should pass...
  ### override:PASS
  ### multi:PASS

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
919646d2a3 selftests/bpf: extend the storage test to test per-cpu cgroup storage
This test extends the cgroup storage test to use per-cpu flavor
of the cgroup storage as well.

The test initializes a per-cpu cgroup storage to some non-zero initial
value (1000), and then simple bumps a per-cpu counter each time
the shared counter is atomically incremented. Then it reads all
per-cpu areas from the userspace side, and checks that the sum
of values adds to the expected sum.

Expected output:
  $ ./test_cgroup_storage
  test_cgroup_storage:PASS

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
a3c6054f81 selftests/bpf: add verifier per-cpu cgroup storage tests
This commits adds verifier tests covering per-cpu cgroup storage
functionality. There are 6 new tests, which are exactly the same
as for shared cgroup storage, but do use per-cpu cgroup storage
map.

Expected output:
  $ ./test_verifier
  #0/u add+sub+mul OK
  #0/p add+sub+mul OK
  ...
  #286/p invalid cgroup storage access 6 OK
  #287/p valid per-cpu cgroup storage access OK
  #288/p invalid per-cpu cgroup storage access 1 OK
  #289/p invalid per-cpu cgroup storage access 2 OK
  #290/p invalid per-cpu cgroup storage access 3 OK
  #291/p invalid per-cpu cgroup storage access 4 OK
  #292/p invalid per-cpu cgroup storage access 5 OK
  #293/p invalid per-cpu cgroup storage access 6 OK
  #294/p multiple registers share map_lookup_elem result OK
  ...
  #662/p mov64 src == dst OK
  #663/p mov64 src != dst OK
  Summary: 914 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
e54870924f bpftool: add support for PERCPU_CGROUP_STORAGE maps
This commit adds support for BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
map type.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
25025e0aab bpf: sync include/uapi/linux/bpf.h to tools/include/uapi/linux/bpf.h
The sync is required due to the appearance of a new map type:
BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE, which implements per-cpu
cgroup local storage.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
c6fdcd6e0c bpf: don't allow create maps of per-cpu cgroup local storages
Explicitly forbid creating map of per-cpu cgroup local storages.
This behavior matches the behavior of shared cgroup storages.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:33 +02:00
Roman Gushchin
b741f16303 bpf: introduce per-cpu cgroup local storage
This commit introduced per-cpu cgroup local storage.

Per-cpu cgroup local storage is very similar to simple cgroup storage
(let's call it shared), except all the data is per-cpu.

The main goal of per-cpu variant is to implement super fast
counters (e.g. packet counters), which don't require neither
lookups, neither atomic operations.

>From userspace's point of view, accessing a per-cpu cgroup storage
is similar to other per-cpu map types (e.g. per-cpu hashmaps and
arrays).

Writing to a per-cpu cgroup storage is not atomic, but is performed
by copying longs, so some minimal atomicity is here, exactly
as with other per-cpu maps.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:32 +02:00
Roman Gushchin
f294b37ec7 bpf: rework cgroup storage pointer passing
To simplify the following introduction of per-cpu cgroup storage,
let's rework a bit a mechanism of passing a pointer to a cgroup
storage into the bpf_get_local_storage(). Let's save a pointer
to the corresponding bpf_cgroup_storage structure, instead of
a pointer to the actual buffer.

It will help us to handle per-cpu storage later, which has
a different way of accessing to the actual data.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:32 +02:00
Roman Gushchin
8bad74f984 bpf: extend cgroup bpf core to allow multiple cgroup storage types
In order to introduce per-cpu cgroup storage, let's generalize
bpf cgroup core to support multiple cgroup storage types.
Potentially, per-node cgroup storage can be added later.

This commit is mostly a formal change that replaces
cgroup_storage pointer with a array of cgroup_storage pointers.
It doesn't actually introduce a new storage type,
it will be done later.

Each bpf program is now able to have one cgroup storage of each type.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-01 16:18:32 +02:00
Yonghong Song
5bf7a60b8e bpf: permit CGROUP_DEVICE programs accessing helper bpf_get_current_cgroup_id()
Currently, helper bpf_get_current_cgroup_id() is not permitted
for CGROUP_DEVICE type of programs. If the helper is used
in such cases, the verifier will log the following error:

  0: (bf) r6 = r1
  1: (69) r7 = *(u16 *)(r6 +0)
  2: (85) call bpf_get_current_cgroup_id#80
  unknown func bpf_get_current_cgroup_id#80

The bpf_get_current_cgroup_id() is useful for CGROUP_DEVICE
type of programs in order to customize action based on cgroup id.
This patch added such a support.

Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-28 14:15:19 +02:00
Daniel Borkmann
78e6e5c11a Merge branch 'bpf-libbpf-attach-by-name'
Andrey Ignatov says:

====================
This patch set introduces libbpf_attach_type_by_name function in libbpf
to identify attach type by section name.

This is useful to avoid writing same logic over and over again in user
space applications that leverage libbpf.

Patch 1 has more details on the new function and problem being solved.
Patches 2 and 3 add support for new section names.
Patch 4 uses new function in a selftest.
Patch 5 adds selftest for libbpf_{prog,attach}_type_by_name.

As a side note there are a lot of inconsistencies now between names used
by libbpf and bpftool (e.g. cgroup/skb vs cgroup_skb, cgroup_device and
device vs cgroup/dev, sockops vs sock_ops, etc). This patch set does not
address it but it tries not to make it harder to address it in the future.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:19:34 +02:00
Andrey Ignatov
370920c47b selftests/bpf: Test libbpf_{prog,attach}_type_by_name
Add selftest for libbpf functions libbpf_prog_type_by_name and
libbpf_attach_type_by_name.

Example of output:
  % ./tools/testing/selftests/bpf/test_section_names
  Summary: 35 PASSED, 0 FAILED

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:14:59 +02:00
Andrey Ignatov
c9bf507d0a selftests/bpf: Use libbpf_attach_type_by_name in test_socket_cookie
Use newly introduced libbpf_attach_type_by_name in test_socket_cookie
selftest.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:14:59 +02:00
Andrey Ignatov
c6f6851b28 libbpf: Support sk_skb/stream_{parser, verdict} section names
Add section names for BPF_SK_SKB_STREAM_PARSER and
BPF_SK_SKB_STREAM_VERDICT attach types to be able to identify them in
libbpf_attach_type_by_name.

"stream_parser" and "stream_verdict" are used instead of simple "parser"
and "verdict" just to avoid possible confusion in a place where attach
type is used alone (e.g. in bpftool's show sub-commands) since there is
another attach point that can be named as "verdict": BPF_SK_MSG_VERDICT.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:14:59 +02:00
Andrey Ignatov
bafa7afe63 libbpf: Support cgroup_skb/{e,in}gress section names
Add section names for BPF_CGROUP_INET_INGRESS and BPF_CGROUP_INET_EGRESS
attach types to be able to identify them in libbpf_attach_type_by_name.

"cgroup_skb" is used instead of "cgroup/skb" mostly to easy possible
unifying of how libbpf and bpftool works with section names:
* bpftool uses "cgroup_skb" to in "prog list" sub-command;
* bpftool uses "ingress" and "egress" in "cgroup list" sub-command;
* having two parts instead of three in a string like "cgroup_skb/ingress"
  can be leveraged to split it to prog_type part and attach_type part,
  or vise versa: use two parts to make a section name.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:14:59 +02:00
Andrey Ignatov
956b620fcf libbpf: Introduce libbpf_attach_type_by_name
There is a common use-case when ELF object contains multiple BPF
programs and every program has its own section name. If it's cgroup-bpf
then programs have to be 1) loaded and 2) attached to a cgroup.

It's convenient to have information necessary to load BPF program
together with program itself. This is where section name works fine in
conjunction with libbpf_prog_type_by_name that identifies prog_type and
expected_attach_type and these can be used with BPF_PROG_LOAD.

But there is currently no way to identify attach_type by section name
and it leads to messy code in user space that reinvents guessing logic
every time it has to identify attach type to use with BPF_PROG_ATTACH.

The patch introduces libbpf_attach_type_by_name that guesses attach type
by section name if a program can be attached.

The difference between expected_attach_type provided by
libbpf_prog_type_by_name and attach_type provided by
libbpf_attach_type_by_name is the former is used at BPF_PROG_LOAD time
and can be zero if a program of prog_type X has only one corresponding
attach type Y whether the latter provides specific attach type to use
with BPF_PROG_ATTACH.

No new section names were added to section_names array. Only existing
ones were reorganized and attach_type was added where appropriate.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:14:59 +02:00
Song Liu
100811936f bpf: test_bpf: add init_net to dev for flow_dissector
Latest changes in __skb_flow_dissect() assume skb->dev has valid nd_net.
However, this is not true for test_bpf. As a result, test_bpf.ko crashes
the system with the following stack trace:

[ 1133.716622] BUG: unable to handle kernel paging request at 0000000000001030
[ 1133.716623] PGD 8000001fbf7ee067
[ 1133.716624] P4D 8000001fbf7ee067
[ 1133.716624] PUD 1f6c1cf067
[ 1133.716625] PMD 0
[ 1133.716628] Oops: 0000 [#1] SMP PTI
[ 1133.716630] CPU: 7 PID: 40473 Comm: modprobe Kdump: loaded Not tainted 4.19.0-rc5-00805-gca11cc92ccd2 #1167
[ 1133.716631] Hardware name: Wiwynn Leopard-Orv2/Leopard-DDR BW, BIOS LBM12.5 12/06/2017
[ 1133.716638] RIP: 0010:__skb_flow_dissect+0x83/0x1680
[ 1133.716639] Code: 04 00 00 41 0f b7 44 24 04 48 85 db 4d 8d 14 07 0f 84 01 02 00 00 48 8b 43 10 48 85 c0 0f 84 e5 01 00 00 48 8b 80 a8 04 00 00 <48> 8b 90 30 10 00 00 48 85 d2 0f 84 dd 01 00 00 31 c0 b9 05 00 00
[ 1133.716640] RSP: 0018:ffffc900303c7a80 EFLAGS: 00010282
[ 1133.716642] RAX: 0000000000000000 RBX: ffff881fea0b7400 RCX: 0000000000000000
[ 1133.716643] RDX: ffffc900303c7bb4 RSI: ffffffff8235c3e0 RDI: ffff881fea0b7400
[ 1133.716643] RBP: ffffc900303c7b80 R08: 0000000000000000 R09: 000000000000000e
[ 1133.716644] R10: ffffc900303c7bb4 R11: ffff881fb6840400 R12: ffffffff8235c3e0
[ 1133.716645] R13: 0000000000000008 R14: 000000000000001e R15: ffffc900303c7bb4
[ 1133.716646] FS:  00007f54e75d3740(0000) GS:ffff881fff5c0000(0000) knlGS:0000000000000000
[ 1133.716648] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1133.716649] CR2: 0000000000001030 CR3: 0000001f6c226005 CR4: 00000000003606e0
[ 1133.716649] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1133.716650] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1133.716651] Call Trace:
[ 1133.716660]  ? sched_clock_cpu+0xc/0xa0
[ 1133.716662]  ? sched_clock_cpu+0xc/0xa0
[ 1133.716665]  ? log_store+0x1b5/0x260
[ 1133.716667]  ? up+0x12/0x60
[ 1133.716669]  ? skb_get_poff+0x4b/0xa0
[ 1133.716674]  ? __kmalloc_reserve.isra.47+0x2e/0x80
[ 1133.716675]  skb_get_poff+0x4b/0xa0
[ 1133.716680]  bpf_skb_get_pay_offset+0xa/0x10
[ 1133.716686]  ? test_bpf_init+0x578/0x1000 [test_bpf]
[ 1133.716690]  ? netlink_broadcast_filtered+0x153/0x3d0
[ 1133.716695]  ? free_pcppages_bulk+0x324/0x600
[ 1133.716696]  ? 0xffffffffa0279000
[ 1133.716699]  ? do_one_initcall+0x46/0x1bd
[ 1133.716704]  ? kmem_cache_alloc_trace+0x144/0x1a0
[ 1133.716709]  ? do_init_module+0x5b/0x209
[ 1133.716712]  ? load_module+0x2136/0x25d0
[ 1133.716715]  ? __do_sys_finit_module+0xba/0xe0
[ 1133.716717]  ? __do_sys_finit_module+0xba/0xe0
[ 1133.716719]  ? do_syscall_64+0x48/0x100
[ 1133.716724]  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9

This patch fixes tes_bpf by using init_net in the dummy dev.

Fixes: d58e468b11 ("flow_dissector: implements flow dissector BPF hook")
Reported-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Petar Penkov <ppenkov@google.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:09:45 +02:00
Andrey Ignatov
53d6eb08e9 bpftool: Fix bpftool net output
Print `bpftool net` output to stdout instead of stderr. Only errors
should be printed to stderr. Regular output should go to stdout and this
is what all other subcommands of bpftool do, including --json and
--pretty formats of `bpftool net` itself.

Fixes: commit f6f3bac08f ("tools/bpf: bpftool: add net support")
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-27 21:07:44 +02:00
Maciej Żenczykowski
1042caa79e net-ipv4: remove 2 always zero parameters from ipv4_redirect()
(the parameters in question are mark and flow_flags)

Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:30:55 -07:00