Commit Graph

274 Commits

Author SHA1 Message Date
Martin KaFai Lau
e34d98d3b4 bpf: btf: Some test_btf clean up
This patch adds a CHECK() macro for condition checking
and error report purpose.  Something similar to test_progs.c

It also counts the number of tests passed/skipped/failed and
print them at the end of the test run.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 17:25:14 +02:00
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
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
Song Liu
a4e21ff8d9 bpf: minor fix to selftest test_stacktrace_build_id()
1. remove useless parameter list to ./urandom_read
2. add missing "\n" to the end of an error message

Fixes: 81f77fd0de ("bpf: add selftest for stackmap with BPF_F_STACK_BUILD_ID")
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-02 00:18:06 +02:00
Yonghong Song
79b4535013 tools/bpf: add a test for bpf_get_stack with tracepoint prog
The test_stacktrace_map and test_stacktrace_build_id are
enhanced to call bpf_get_stack in the helper to get the
stack trace as well.  The stack traces from bpf_get_stack
and bpf_get_stackid are compared to ensure that for the
same stack as represented as the same hash, their ip addresses
or build id's must be the same.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:54 -07:00
Yonghong Song
173965fbfb tools/bpf: add a test for bpf_get_stack with raw tracepoint prog
The test attached a raw_tracepoint program to raw_syscalls/sys_enter.
It tested to get stack for user space, kernel space and user
space with build_id request. It also tested to get user
and kernel stack into the same buffer with back-to-back
bpf_get_stack helper calls.

If jit is not enabled, the user space application will check
to ensure that the kernel function for raw_tracepoint
___bpf_prog_run is part of the stack.

If jit is enabled, we did not have a reliable way to
verify the kernel stack, so just assume the kernel stack
is good when the kernel stack size is greater than 0.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:54 -07:00
Yonghong Song
2abe611c5f tools/bpf: add a verifier test case for bpf_get_stack helper and ARSH
The test_verifier already has a few ARSH test cases.
This patch adds a new test case which takes advantage of newly
improved verifier behavior for bpf_get_stack and ARSH.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:54 -07:00
Yonghong Song
28dbf861de samples/bpf: move common-purpose trace functions to selftests
There is no functionality change in this patch. The common-purpose
trace functions, including perf_event polling and ksym lookup,
are moved from trace_output_user.c and bpf_load.c to
selftests/bpf/trace_helpers.c so that these function can
be reused later in selftests.

Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:54 -07:00
Yonghong Song
de2ff05f48 tools/bpf: add bpf_get_stack helper to tools headers
The tools header file bpf.h is synced with kernel uapi bpf.h.
The new helper is also added to bpf_helpers.h.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
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
William Tu
933a741e3b selftests/bpf: bpf tunnel test.
The patch migrates the original tests at samples/bpf/tcbpf2_kern.c
and samples/bpf/test_tunnel_bpf.sh to selftests.  There are a couple
changes from the original:
    1) add ipv6 vxlan, ipv6 geneve, ipv6 ipip tests
    2) simplify the original ipip tests (remove iperf tests)
    3) improve documentation
    4) use bpf_ntoh* and bpf_hton* api

In summary, 'test_tunnel_kern.o' contains the following bpf program:
  GRE: gre_set_tunnel, gre_get_tunnel
  IP6GRE: ip6gretap_set_tunnel, ip6gretap_get_tunnel
  ERSPAN: erspan_set_tunnel, erspan_get_tunnel
  IP6ERSPAN: ip4ip6erspan_set_tunnel, ip4ip6erspan_get_tunnel
  VXLAN: vxlan_set_tunnel, vxlan_get_tunnel
  IP6VXLAN: ip6vxlan_set_tunnel, ip6vxlan_get_tunnel
  GENEVE: geneve_set_tunnel, geneve_get_tunnel
  IP6GENEVE: ip6geneve_set_tunnel, ip6geneve_get_tunnel
  IPIP: ipip_set_tunnel, ipip_get_tunnel
  IP6IP: ipip6_set_tunnel, ipip6_get_tunnel,
         ip6ip6_set_tunnel, ip6ip6_get_tunnel
  XFRM: xfrm_get_state

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:11:14 +02:00
David S. Miller
c749fa181b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-24 23:59:11 -04:00
John Fastabend
a18fda1a62 bpf: reduce runtime of test_sockmap tests
When test_sockmap was running outside of selftests and was not being
run by build bots it was reasonable to spend significant amount of
time running various tests. The number of tests is high because many
different I/O iterators are run.

However, now that test_sockmap is part of selftests rather than
iterate through all I/O sides only test a minimal set of min/max
values along with a few "normal" I/O ops. Also remove the long
running tests. They can be run from other test frameworks on a regular
cadence.

This significanly reduces runtime of test_sockmap.

Before:

$ time sudo ./test_sockmap  > /dev/null

real    4m47.521s
user    0m0.370s
sys     0m3.131s

After:

$ time sudo ./test_sockmap  > /dev/null

real    0m0.514s
user    0m0.104s
sys     0m0.430s

The CLI is still available for users that want to test the long
running tests that do the larger send/recv tests.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-25 02:13:01 +02:00
John Fastabend
16962b2404 bpf: sockmap, add selftests
This adds a new test program test_sockmap which is the old sample
sockmap program. By moving the sample program here we can now run it
as part of the self tests suite. To support this a populate_progs()
routine is added to load programs and maps which was previously done
with load_bpf_file(). This is needed because self test libs do not
provide a similar routine. Also we now use the cgroup_helpers
routines to manage cgroup use instead of manually creating one and
supplying it to the CLI.

Notice we keep the CLI around though because it is useful for dbg
and specialized testing.

To run use ./test_sockmap and the result should be,

Summary 660 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-25 00:06:20 +02:00
Yonghong Song
6595c7426a tools/bpf: remove test_sock_addr from TEST_GEN_PROGS
Since test_sock_addr is not supposed to run by itself,
remove it from TEST_GEN_PROGS and add it to
TEST_GEN_PROGS_EXTENDED. This way, run_tests will
not run test_sock_addr. The corresponding test to run
is test_sock_addr.sh.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-25 00:00:06 +02:00
Anders Roxell
b6fd9cf796 selftests: bpf: update .gitignore with missing file
Fixes: c0fa1b6c3e ("bpf: btf: Add BTF tests")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 23:51:45 +02:00
Paul Chaignon
5f90dd6aae tools/bpf: add verifier tests for accesses to map values
This patch adds new test cases for accesses to map values from map
helpers.

Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 22:39:13 +02:00
Eyal Birger
29a36f9eef samples/bpf: extend test_tunnel_bpf.sh with xfrm state test
Add a test for fetching xfrm state parameters from a tc program running
on ingress.

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
Martin KaFai Lau
c0fa1b6c3e bpf: btf: Add BTF tests
This patch tests the BTF loading, map_create with BTF
and the changes in libbpf.

-r: Raw tests that test raw crafted BTF data
-f: Test LLVM compiled bpf prog with BTF data
-g: Test BPF_OBJ_GET_INFO_BY_FD for btf_fd
-p: Test pretty print

The tools/testing/selftests/bpf/Makefile will probe
for BTF support in llc and pahole before generating
debug info (-g) and convert them to BTF.  You can supply
the BTF supported binary through the following make variables:
LLC, BTF_PAHOLE and LLVM_OBJCOPY.

LLC: The lastest llc with -mattr=dwarfris support for the bpf target.
     It is only in the master of the llvm repo for now.
BTF_PAHOLE: The modified pahole with BTF support:
	    https://github.com/iamkafai/pahole/tree/btf
	    To add a BTF section: "pahole -J bpf_prog.o"
LLVM_OBJCOPY: Any llvm-objcopy should do

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:47:42 +02:00
Yonghong Song
0a0a7e00a2 tools/bpf: fix test_sock and test_sock_addr.sh failure
The bpf selftests test_sock and test_sock_addr.sh failed
in my test machine. The failure looks like:
    $ ./test_sock
    Test case: bind4 load with invalid access: src_ip6 .. [PASS]
    Test case: bind4 load with invalid access: mark .. [PASS]
    Test case: bind6 load with invalid access: src_ip4 .. [PASS]
    Test case: sock_create load with invalid access: src_port .. [PASS]
    Test case: sock_create load w/o expected_attach_type (compat mode) .. [FAIL]
    Test case: sock_create load w/ expected_attach_type .. [FAIL]
    Test case: attach type mismatch bind4 vs bind6 .. [FAIL]
    ...
    Summary: 4 PASSED, 12 FAILED
    $ ./test_sock_addr.sh
    Wait for testing IPv4/IPv6 to become available .....
    ERROR: Timeout waiting for test IP to become available.

In test_sock, bpf program loads failed due to hitting memlock limits.
In test_sock_addr.sh, my test machine is a ipv6 only test box and using
"ping" without specifying address family for an ipv6 address does not work.

This patch fixed the issue by including header bpf_rlimit.h in test_sock.c
and test_sock_addr.c, and specifying address family for ping command.

Cc: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 00:16:37 +02:00
Nikita V. Shirokov
c6ffd1ff78 bpf: add bpf_xdp_adjust_tail sample prog
adding bpf's sample program which is using bpf_xdp_adjust_tail helper
by generating ICMPv4 "packet to big" message if ingress packet's size is
bigger then 600 bytes

Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-18 23:34:17 +02:00
Nikita V. Shirokov
0367d0a294 bpf: adding tests for bpf_xdp_adjust_tail
adding selftests for bpf_xdp_adjust_tail helper. in this synthetic test
we are testing that 1) if data_end < data helper will return EINVAL
2) for normal use case packet's length would be reduced.

Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-18 23:34:17 +02:00
Anders Roxell
0abf854d7c selftests: bpf: update .gitignore with missing generated files
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-11 00:59:30 +02:00
Andrey Ignatov
1d436885b2 selftests/bpf: Selftest for sys_bind post-hooks.
Add selftest for attach types `BPF_CGROUP_INET4_POST_BIND` and
`BPF_CGROUP_INET6_POST_BIND`.

The main things tested are:
* prog load behaves as expected (valid/invalid accesses in prog);
* prog attach behaves as expected (load- vs attach-time attach types);
* `BPF_CGROUP_INET_SOCK_CREATE` can be attached in a backward compatible
  way;
* post-hooks return expected result and errno.

Example:
  # ./test_sock
  Test case: bind4 load with invalid access: src_ip6 .. [PASS]
  Test case: bind4 load with invalid access: mark .. [PASS]
  Test case: bind6 load with invalid access: src_ip4 .. [PASS]
  Test case: sock_create load with invalid access: src_port .. [PASS]
  Test case: sock_create load w/o expected_attach_type (compat mode) ..
  [PASS]
  Test case: sock_create load w/ expected_attach_type .. [PASS]
  Test case: attach type mismatch bind4 vs bind6 .. [PASS]
  Test case: attach type mismatch bind6 vs bind4 .. [PASS]
  Test case: attach type mismatch default vs bind4 .. [PASS]
  Test case: attach type mismatch bind6 vs sock_create .. [PASS]
  Test case: bind4 reject all .. [PASS]
  Test case: bind6 reject all .. [PASS]
  Test case: bind6 deny specific IP & port .. [PASS]
  Test case: bind4 allow specific IP & port .. [PASS]
  Test case: bind4 allow all .. [PASS]
  Test case: bind6 allow all .. [PASS]
  Summary: 16 PASSED, 0 FAILED

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-31 02:16:40 +02:00
Andrey Ignatov
622adafb2a selftests/bpf: Selftest for sys_connect hooks
Add selftest for BPF_CGROUP_INET4_CONNECT and BPF_CGROUP_INET6_CONNECT
attach types.

Try to connect(2) to specified IP:port and test that:
* remote IP:port pair is overridden;
* local end of connection is bound to specified IP.

All combinations of IPv4/IPv6 and TCP/UDP are tested.

Example:
  # tcpdump -pn -i lo -w connect.pcap 2>/dev/null &
  [1] 478
  # strace -qqf -e connect -o connect.trace ./test_sock_addr.sh
  Wait for testing IPv4/IPv6 to become available ... OK
  Load bind4 with invalid type (can pollute stderr) ... REJECTED
  Load bind4 with valid type ... OK
  Attach bind4 with invalid type ... REJECTED
  Attach bind4 with valid type ... OK
  Load connect4 with invalid type (can pollute stderr) libbpf: load bpf \
    program failed: Permission denied
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:
  0: (b7) r2 = 23569
  1: (63) *(u32 *)(r1 +24) = r2
  2: (b7) r2 = 16777343
  3: (63) *(u32 *)(r1 +4) = r2
  invalid bpf_context access off=4 size=4
  [ 1518.404609] random: crng init done

  libbpf: -- END LOG --
  libbpf: failed to load program 'cgroup/connect4'
  libbpf: failed to load object './connect4_prog.o'
  ... REJECTED
  Load connect4 with valid type ... OK
  Attach connect4 with invalid type ... REJECTED
  Attach connect4 with valid type ... OK
  Test case #1 (IPv4/TCP):
          Requested: bind(192.168.1.254, 4040) ..
             Actual: bind(127.0.0.1, 4444)
          Requested: connect(192.168.1.254, 4040) from (*, *) ..
             Actual: connect(127.0.0.1, 4444) from (127.0.0.4, 56068)
  Test case #2 (IPv4/UDP):
          Requested: bind(192.168.1.254, 4040) ..
             Actual: bind(127.0.0.1, 4444)
          Requested: connect(192.168.1.254, 4040) from (*, *) ..
             Actual: connect(127.0.0.1, 4444) from (127.0.0.4, 56447)
  Load bind6 with invalid type (can pollute stderr) ... REJECTED
  Load bind6 with valid type ... OK
  Attach bind6 with invalid type ... REJECTED
  Attach bind6 with valid type ... OK
  Load connect6 with invalid type (can pollute stderr) libbpf: load bpf \
    program failed: Permission denied
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:
  0: (b7) r6 = 0
  1: (63) *(u32 *)(r1 +12) = r6
  invalid bpf_context access off=12 size=4

  libbpf: -- END LOG --
  libbpf: failed to load program 'cgroup/connect6'
  libbpf: failed to load object './connect6_prog.o'
  ... REJECTED
  Load connect6 with valid type ... OK
  Attach connect6 with invalid type ... REJECTED
  Attach connect6 with valid type ... OK
  Test case #3 (IPv6/TCP):
          Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
             Actual: bind(::1, 6666)
          Requested: connect(face:b00c:1234:5678::abcd, 6060) from (*, *)
             Actual: connect(::1, 6666) from (::6, 37458)
  Test case #4 (IPv6/UDP):
          Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
             Actual: bind(::1, 6666)
          Requested: connect(face:b00c:1234:5678::abcd, 6060) from (*, *)
             Actual: connect(::1, 6666) from (::6, 39315)
  ### SUCCESS
  # egrep 'connect\(.*AF_INET' connect.trace | \
  > egrep -vw 'htons\(1025\)' | fold -b -s -w 72
  502   connect(7, {sa_family=AF_INET, sin_port=htons(4040),
  sin_addr=inet_addr("192.168.1.254")}, 128) = 0
  502   connect(8, {sa_family=AF_INET, sin_port=htons(4040),
  sin_addr=inet_addr("192.168.1.254")}, 128) = 0
  502   connect(9, {sa_family=AF_INET6, sin6_port=htons(6060),
  inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr),
  sin6_flowinfo=0, sin6_scope_id=0}, 128) = 0
  502   connect(10, {sa_family=AF_INET6, sin6_port=htons(6060),
  inet_pton(AF_INET6, "face:b00c:1234:5678::abcd", &sin6_addr),
  sin6_flowinfo=0, sin6_scope_id=0}, 128) = 0
  # fg
  tcpdump -pn -i lo -w connect.pcap 2> /dev/null
  # tcpdump -r connect.pcap -n tcp | cut -c 1-72
  reading from file connect.pcap, link-type EN10MB (Ethernet)
  17:57:40.383533 IP 127.0.0.4.56068 > 127.0.0.1.4444: Flags [S], seq 1333
  17:57:40.383566 IP 127.0.0.1.4444 > 127.0.0.4.56068: Flags [S.], seq 112
  17:57:40.383589 IP 127.0.0.4.56068 > 127.0.0.1.4444: Flags [.], ack 1, w
  17:57:40.384578 IP 127.0.0.1.4444 > 127.0.0.4.56068: Flags [R.], seq 1,
  17:57:40.403327 IP6 ::6.37458 > ::1.6666: Flags [S], seq 406513443, win
  17:57:40.403357 IP6 ::1.6666 > ::6.37458: Flags [S.], seq 2448389240, ac
  17:57:40.403376 IP6 ::6.37458 > ::1.6666: Flags [.], ack 1, win 342, opt
  17:57:40.404263 IP6 ::1.6666 > ::6.37458: Flags [R.], seq 1, ack 1, win

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-31 02:16:14 +02:00
Andrey Ignatov
e50b0a6f08 selftests/bpf: Selftest for sys_bind hooks
Add selftest to work with bpf_sock_addr context from
`BPF_PROG_TYPE_CGROUP_SOCK_ADDR` programs.

Try to bind(2) on IP:port and apply:
* loads to make sure context can be read correctly, including narrow
  loads (byte, half) for IP and full-size loads (word) for all fields;
* stores to those fields allowed by verifier.

All combination from IPv4/IPv6 and TCP/UDP are tested.

Both scenarios are tested:
* valid programs can be loaded and attached;
* invalid programs can be neither loaded nor attached.

Test passes when expected data can be read from context in the
BPF-program, and after the call to bind(2) socket is bound to IP:port
pair that was written by BPF-program to the context.

Example:
  # ./test_sock_addr
  Attached bind4 program.
  Test case #1 (IPv4/TCP):
          Requested: bind(192.168.1.254, 4040) ..
             Actual: bind(127.0.0.1, 4444)
  Test case #2 (IPv4/UDP):
          Requested: bind(192.168.1.254, 4040) ..
             Actual: bind(127.0.0.1, 4444)
  Attached bind6 program.
  Test case #3 (IPv6/TCP):
          Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
             Actual: bind(::1, 6666)
  Test case #4 (IPv6/UDP):
          Requested: bind(face:b00c:1234:5678::abcd, 6060) ..
             Actual: bind(::1, 6666)
  ### SUCCESS

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-31 02:15:30 +02:00
Alexei Starovoitov
3bbe086988 selftests/bpf: test for bpf_get_stackid() from raw tracepoints
similar to traditional traceopint test add bpf_get_stackid() test
from raw tracepoints
and reduce verbosity of existing stackmap test

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28 22:55:19 +02:00
John Fastabend
0dcbbf6785 bpf: sockmap sample test for bpf_msg_pull_data
This adds an option to test the msg_pull_data helper. This
uses two options txmsg_start and txmsg_end to let the user
specify start and end bytes to pull.

The options can be used with txmsg_apply, txmsg_cork options
as well as with any of the basic tests, txmsg, txmsg_redir and
txmsg_drop (plus noisy variants) to run pull_data inline with
those tests. By giving user direct control over the variables
we can easily do negative testing as well as positive tests.

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>
2018-03-19 21:14:41 +01:00
John Fastabend
468b3fdea8 bpf: sockmap sample support for bpf_msg_cork_bytes()
Add sample application support for the bpf_msg_cork_bytes helper. This
lets the user specify how many bytes each verdict should apply to.

Similar to apply_bytes() tests these can be run as a stand-alone test
when used without other options or inline with other tests by using
the txmsg_cork option along with any of the basic tests txmsg,
txmsg_redir, txmsg_drop.

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>
2018-03-19 21:14:40 +01:00
John Fastabend
1c16c3126a bpf: sockmap, add sample option to test apply_bytes helper
This adds an option to test the apply_bytes helper. This option lets
the user specify an int on the command line specifying how much data
each verdict should apply to.

When this is set a map entry is set with the bytes input by the user
and then the specified program --txmsg or --txmsg_redir will use the
value and set the applied data. If no other option is set then a
default --txmsg_apply program is run. This program will drop pkts
if an error is detected on the bytes map lookup. Useful to verify
the map lookup and apply helper are working and causing a hard
error if it is not.

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>
2018-03-19 21:14:40 +01:00
John Fastabend
4c4c3c276c bpf: sockmap sample, add option to attach SK_MSG program
Add sockmap option to use SK_MSG program types.

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>
2018-03-19 21:14:40 +01:00
John Fastabend
1acc60b6a4 bpf: add verifier tests for BPF_PROG_TYPE_SK_MSG
Test read and writes for BPF_PROG_TYPE_SK_MSG.

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>
2018-03-19 21:14:39 +01:00
John Fastabend
82a8616889 bpf: add map tests for BPF_PROG_TYPE_SK_MSG
Add map tests to attach BPF_PROG_TYPE_SK_MSG types to a sockmap.

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>
2018-03-19 21:14:39 +01:00
Song Liu
81f77fd0de bpf: add selftest for stackmap with BPF_F_STACK_BUILD_ID
test_stacktrace_build_id() is added. It accesses tracepoint urandom_read
with "dd" and "urandom_read" and gathers stack traces. Then it reads the
stack traces from the stackmap.

urandom_read is a statically link binary that reads from /dev/urandom.
test_stacktrace_build_id() calls readelf to read build ID of urandom_read
and compares it with build ID from the stackmap.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-15 01:10:02 +01:00
David S. Miller
0f3e9c97eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All of the conflicts were cases of overlapping changes.

In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-06 01:20:46 -05:00
Daniel Borkmann
b33eb73583 bpf: add tail call tests to test_verifier
One of the downsides of the test_bpf module was that since being
in kernel space, it couldn't test-run tail calls. Now that the
test_verifier has the ability to perform run-time tests, populate
the prog array so we actually jump into other BPF programs and
can check all corner cases. Most useful in combination with JITs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-26 20:11:23 -08:00
Daniel Borkmann
fe8d662aef bpf: unify rlimit handling in selftests
Unify memlock handling into bpf_rlimit.h and replace all occurences
in BPF kselftests with it.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-26 20:11:23 -08:00
David S. Miller
ba6056a41c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-02-26

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

The main changes are:

1) Various improvements for BPF kselftests: i) skip unprivileged tests
   when kernel.unprivileged_bpf_disabled sysctl knob is set, ii) count
   the number of skipped tests from unprivileged, iii) when a test case
   had an unexpected error then print the actual but also the unexpected
   one for better comparison, from Joe.

2) Add a sample program for collecting CPU state statistics with regards
   to how long the CPU resides in cstate and pstate levels. Based on
   cpu_idle and cpu_frequency trace points, from Leo.

3) Various x64 BPF JIT optimizations to further shrink the generated
   image size in order to make it more icache friendly. When tested on
   the Cilium generated programs, image size reduced by approx 4-5% in
   best case mainly due to how LLVM emits unsigned 32 bit constants,
   from Daniel.

4) Improvements and fixes on the BPF sockmap sample programs: i) fix
   the sockmap's Makefile to include nlattr.o for libbpf, ii) detach
   the sock ops programs from the cgroup before exit, from Prashant.

5) Avoid including xdp.h in filter.h by just forward declaring the
   struct xdp_rxq_info in filter.h, from Jesper.

6) Fix the BPF kselftests Makefile for cgroup_helpers.c by only declaring
   it a dependency for test_dev_cgroup.c but not every other test case
   where it is not needed, from Jesper.

7) Adjust rlimit RLIMIT_MEMLOCK for test_tcpbpf_user selftest since the
   default is insufficient for creating the 'global_map' used in the
   corresponding BPF program, from Yonghong.

8) Likewise, for the xdp_redirect sample, Tushar ran into the same when
   invoking xdp_redirect and xdp_monitor at the same time, therefore
   in order to have the sample generically work bump the limit here,
   too. Fix from Tushar.

9) Avoid an unnecessary NULL check in BPF_CGROUP_RUN_PROG_INET_SOCK()
   since sk is always guaranteed to be non-NULL, from Yafang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-26 10:37:24 -05:00
Daniel Borkmann
23d191a82c bpf: add various jit test cases
Add few test cases that check the rnu-time results under JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-23 22:50:00 -08:00
Daniel Borkmann
ca36960211 bpf: allow xadd only on aligned memory
The requirements around atomic_add() / atomic64_add() resp. their
JIT implementations differ across architectures. E.g. while x86_64
seems just fine with BPF's xadd on unaligned memory, on arm64 it
triggers via interpreter but also JIT the following crash:

  [  830.864985] Unable to handle kernel paging request at virtual address ffff8097d7ed6703
  [...]
  [  830.916161] Internal error: Oops: 96000021 [#1] SMP
  [  830.984755] CPU: 37 PID: 2788 Comm: test_verifier Not tainted 4.16.0-rc2+ #8
  [  830.991790] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.29 07/17/2017
  [  830.998998] pstate: 80400005 (Nzcv daif +PAN -UAO)
  [  831.003793] pc : __ll_sc_atomic_add+0x4/0x18
  [  831.008055] lr : ___bpf_prog_run+0x1198/0x1588
  [  831.012485] sp : ffff00001ccabc20
  [  831.015786] x29: ffff00001ccabc20 x28: ffff8017d56a0f00
  [  831.021087] x27: 0000000000000001 x26: 0000000000000000
  [  831.026387] x25: 000000c168d9db98 x24: 0000000000000000
  [  831.031686] x23: ffff000008203878 x22: ffff000009488000
  [  831.036986] x21: ffff000008b14e28 x20: ffff00001ccabcb0
  [  831.042286] x19: ffff0000097b5080 x18: 0000000000000a03
  [  831.047585] x17: 0000000000000000 x16: 0000000000000000
  [  831.052885] x15: 0000ffffaeca8000 x14: 0000000000000000
  [  831.058184] x13: 0000000000000000 x12: 0000000000000000
  [  831.063484] x11: 0000000000000001 x10: 0000000000000000
  [  831.068783] x9 : 0000000000000000 x8 : 0000000000000000
  [  831.074083] x7 : 0000000000000000 x6 : 000580d428000000
  [  831.079383] x5 : 0000000000000018 x4 : 0000000000000000
  [  831.084682] x3 : ffff00001ccabcb0 x2 : 0000000000000001
  [  831.089982] x1 : ffff8097d7ed6703 x0 : 0000000000000001
  [  831.095282] Process test_verifier (pid: 2788, stack limit = 0x0000000018370044)
  [  831.102577] Call trace:
  [  831.105012]  __ll_sc_atomic_add+0x4/0x18
  [  831.108923]  __bpf_prog_run32+0x4c/0x70
  [  831.112748]  bpf_test_run+0x78/0xf8
  [  831.116224]  bpf_prog_test_run_xdp+0xb4/0x120
  [  831.120567]  SyS_bpf+0x77c/0x1110
  [  831.123873]  el0_svc_naked+0x30/0x34
  [  831.127437] Code: 97fffe97 17ffffec 00000000 f9800031 (885f7c31)

Reason for this is because memory is required to be aligned. In
case of BPF, we always enforce alignment in terms of stack access,
but not when accessing map values or packet data when the underlying
arch (e.g. arm64) has CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS set.

xadd on packet data that is local to us anyway is just wrong, so
forbid this case entirely. The only place where xadd makes sense in
fact are map values; xadd on stack is wrong as well, but it's been
around for much longer. Specifically enforce strict alignment in case
of xadd, so that we handle this case generically and avoid such crashes
in the first place.

Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-23 14:33:39 -08:00
Daniel Borkmann
16338a9b3a bpf, arm64: fix out of bounds access in tail call
I recently noticed a crash on arm64 when feeding a bogus index
into BPF tail call helper. The crash would not occur when the
interpreter is used, but only in case of JIT. Output looks as
follows:

  [  347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510
  [...]
  [  347.043065] [fffb850e96492510] address between user and kernel address ranges
  [  347.050205] Internal error: Oops: 96000004 [#1] SMP
  [...]
  [  347.190829] x13: 0000000000000000 x12: 0000000000000000
  [  347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10
  [  347.201427] x9 : 0000000000000000 x8 : 0000000000000000
  [  347.206726] x7 : 0000000000000000 x6 : 001c991738000000
  [  347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a
  [  347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500
  [  347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500
  [  347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61)
  [  347.235221] Call trace:
  [  347.237656]  0xffff000002f3a4fc
  [  347.240784]  bpf_test_run+0x78/0xf8
  [  347.244260]  bpf_prog_test_run_skb+0x148/0x230
  [  347.248694]  SyS_bpf+0x77c/0x1110
  [  347.251999]  el0_svc_naked+0x30/0x34
  [  347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b)
  [...]

In this case the index used in BPF r3 is the same as in r1
at the time of the call, meaning we fed a pointer as index;
here, it had the value 0xffff808fd7cf0500 which sits in x2.

While I found tail calls to be working in general (also for
hitting the error cases), I noticed the following in the code
emission:

  # bpftool p d j i 988
  [...]
  38:   ldr     w10, [x1,x10]
  3c:   cmp     w2, w10
  40:   b.ge    0x000000000000007c              <-- signed cmp
  44:   mov     x10, #0x20                      // #32
  48:   cmp     x26, x10
  4c:   b.gt    0x000000000000007c
  50:   add     x26, x26, #0x1
  54:   mov     x10, #0x110                     // #272
  58:   add     x10, x1, x10
  5c:   lsl     x11, x2, #3
  60:   ldr     x11, [x10,x11]                  <-- faulting insn (f86b694b)
  64:   cbz     x11, 0x000000000000007c
  [...]

Meaning, the tests passed because commit ddb55992b0 ("arm64:
bpf: implement bpf_tail_call() helper") was using signed compares
instead of unsigned which as a result had the test wrongly passing.

Change this but also the tail call count test both into unsigned
and cap the index as u32. Latter we did as well in 90caccdd8c
("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here,
too. Tested on HiSilicon Hi1616.

Result after patch:

  # bpftool p d j i 268
  [...]
  38:	ldr	w10, [x1,x10]
  3c:	add	w2, w2, #0x0
  40:	cmp	w2, w10
  44:	b.cs	0x0000000000000080
  48:	mov	x10, #0x20                  	// #32
  4c:	cmp	x26, x10
  50:	b.hi	0x0000000000000080
  54:	add	x26, x26, #0x1
  58:	mov	x10, #0x110                 	// #272
  5c:	add	x10, x1, x10
  60:	lsl	x11, x2, #3
  64:	ldr	x11, [x10,x11]
  68:	cbz	x11, 0x0000000000000080
  [...]

Fixes: ddb55992b0 ("arm64: bpf: implement bpf_tail_call() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-22 16:06:28 -08:00
Li Zhijian
80475c48c6 selftests/bpf/test_maps: exit child process without error in ENOMEM case
test_maps contains a series of stress tests, and previously it will break the
rest tests when it failed to alloc memory.
-----------------------
Failed to create hashmap key=8 value=262144 'Cannot allocate memory'
Failed to create hashmap key=16 value=262144 'Cannot allocate memory'
Failed to create hashmap key=8 value=262144 'Cannot allocate memory'
Failed to create hashmap key=8 value=262144 'Cannot allocate memory'
test_maps: test_maps.c:955: run_parallel: Assertion `status == 0' failed.
Aborted
not ok 1..3 selftests:  test_maps [FAIL]
-----------------------
after this patch, the rest tests will be continue when it occurs an ENOMEM failure

CC: Alexei Starovoitov <alexei.starovoitov@gmail.com>
CC: Philip Li <philip.li@intel.com>
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Li Zhijian <zhijianx.li@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22 15:21:26 +01:00
Anders Roxell
31a8260d3e selftests/bpf: update gitignore with test_libbpf_open
bpf builds a test program for loading BPF ELF files. Add the executable
to the .gitignore list.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Tested-by: Daniel Díaz <daniel.diaz@linaro.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22 01:41:18 +01:00
Anders Roxell
b52db43a3d selftests/bpf: tcpbpf_kern: use in6_* macros from glibc
Both glibc and the kernel have in6_* macros definitions. Build fails
because it picks up wrong in6_* macro from the kernel header and not the
header from glibc.

Fixes build error below:
clang -I. -I./include/uapi -I../../../include/uapi
     -Wno-compare-distinct-pointer-types \
         -O2 -target bpf -emit-llvm -c test_tcpbpf_kern.c -o - |      \
llc -march=bpf -mcpu=generic -filetype=obj
     -o .../tools/testing/selftests/bpf/test_tcpbpf_kern.o
In file included from test_tcpbpf_kern.c:12:
.../netinet/in.h:101:5: error: expected identifier
    IPPROTO_HOPOPTS = 0,   /* IPv6 Hop-by-Hop options.  */
    ^
.../linux/in6.h:131:26: note: expanded from macro 'IPPROTO_HOPOPTS'
                                ^
In file included from test_tcpbpf_kern.c:12:
/usr/include/netinet/in.h:103:5: error: expected identifier
    IPPROTO_ROUTING = 43,  /* IPv6 routing header.  */
    ^
.../linux/in6.h:132:26: note: expanded from macro 'IPPROTO_ROUTING'
                                ^
In file included from test_tcpbpf_kern.c:12:
.../netinet/in.h:105:5: error: expected identifier
    IPPROTO_FRAGMENT = 44, /* IPv6 fragmentation header.  */
    ^

Since both glibc and the kernel have in6_* macros definitions, use the
one from glibc.  Kernel headers will check for previous libc definitions
by including include/linux/libc-compat.h.

Reported-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Tested-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-22 01:19:37 +01:00
Joe Stringer
0a67487403 selftests/bpf: Only run tests if !bpf_disabled
The "kernel.unprivileged_bpf_disabled" sysctl, if enabled, causes all
unprivileged tests to fail because it permanently disables unprivileged
BPF access for the currently running kernel. Skip the relevant tests if
the user attempts to run the testsuite with this sysctl enabled.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-15 10:22:55 +01:00
Joe Stringer
d0a0e4956f selftests/bpf: Count tests skipped by unpriv
When priviliged tests are skipped due to user rights, count the number of
skipped tests so it's more obvious that the test did not check everything.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-15 10:22:55 +01:00
Joe Stringer
95f87a9706 selftests/bpf: Print unexpected output on fail
This makes it easier to debug off-hand when the error message isn't
exactly as expected.

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-02-15 10:22:55 +01:00
Yonghong Song
615a947498 tools/bpf: adjust rlimit RLIMIT_MEMLOCK for test_tcpbpf_user
The default rlimit RLIMIT_MEMLOCK is 64KB. In certain cases,
e.g. in a test machine mimicking our production system, this test may
fail due to unable to charge the required memory for map creation:
   # ./test_tcpbpf_user
   libbpf: failed to create map (name: 'global_map'): Operation not permitted
   libbpf: failed to load object 'test_tcpbpf_kern.o'
   FAILED: load_bpf_file failed for: test_tcpbpf_kern.o

Changing the default rlimit RLIMIT_MEMLOCK to unlimited makes
the test always pass.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-13 18:02:02 -08:00
Jesper Dangaard Brouer
41757dcb0c selftests/bpf: fix Makefile for cgroup_helpers.c
The current selftests Makefile construct result in cgroup_helpers.c
gets compiled together with all the TEST_GEN_PROGS. And it also result
in invoking the libbpf Makefile two times (tools/lib/bpf).

These issues were introduced in commit 9d1f159419 ("bpf: move
cgroup_helpers from samples/bpf/ to tools/testing/selftesting/bpf/").

The only test program that requires the cgroup helpers is 'test_dev_cgroup'.

Thus, create a make target $(OUTPUT)/test_dev_cgroup that extend[1]
the 'prerequisite' for the 'stem' %-style pattern in ../lib.mk,
for this particular test program.

Reviewers notice the make-rules in tools/testing/selftests/lib.mk
differ from the normal kernel kbuild rules, and it is practical
to use 'make -p' to follow how these 'Implicit/static pattern stem'
gets expanded.

[1] https://www.gnu.org/software/make/manual/html_node/Static-Usage.html

Fixes: 9d1f159419 ("bpf: move cgroup_helpers from samples/bpf/ to tools/testing/selftesting/bpf/")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-13 17:59:06 -08:00