linux-stable.git/tools/testing/selftests/bpf, branch v4.13.2

bpf: fix selftest/bpf/test_pkt_md_access on s390x

2017-08-07T17:06:27+00:00

Commit 18f3d6be6be1 ("selftests/bpf: Add test cases to test narrower ctx field loads")
introduced new eBPF test cases. One of them (test_pkt_md_access.c)
fails on s390x. The BPF verifier error message is:

[root@s8360046 bpf]# ./test_progs
test_pkt_access:PASS:ipv4 349 nsec
test_pkt_access:PASS:ipv6 212 nsec
[....]
libbpf: load bpf program failed: Permission denied
libbpf: -- BEGIN DUMP LOG ---
libbpf:
0: (71) r2 = *(u8 *)(r1 +0)
invalid bpf_context access off=0 size=1

libbpf: -- END LOG --
libbpf: failed to load program 'test1'
libbpf: failed to load object './test_pkt_md_access.o'
Summary: 29 PASSED, 1 FAILED
[root@s8360046 bpf]#

This is caused by a byte endianness issue. S390x is a big endian
architecture.  Pointer access to the lowest byte or halfword of a
four byte value need to add an offset.
On little endian architectures this offset is not needed.

Fix this and use the same approach as the originator used for other files
(for example test_verifier.c) in his original commit.

With this fix the test program test_progs succeeds on s390x:
[root@s8360046 bpf]# ./test_progs
test_pkt_access:PASS:ipv4 236 nsec
test_pkt_access:PASS:ipv6 217 nsec
test_xdp:PASS:ipv4 3624 nsec
test_xdp:PASS:ipv6 1722 nsec
test_l4lb:PASS:ipv4 926 nsec
test_l4lb:PASS:ipv6 1322 nsec
test_tcp_estats:PASS: 0 nsec
test_bpf_obj_id:PASS:get-fd-by-notexist-prog-id 0 nsec
test_bpf_obj_id:PASS:get-fd-by-notexist-map-id 0 nsec
test_bpf_obj_id:PASS:get-prog-info(fd) 0 nsec
test_bpf_obj_id:PASS:get-map-info(fd) 0 nsec
test_bpf_obj_id:PASS:get-prog-info(fd) 0 nsec
test_bpf_obj_id:PASS:get-map-info(fd) 0 nsec
test_bpf_obj_id:PASS:get-prog-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-prog-info(next_id->fd) 0 nsec
test_bpf_obj_id:PASS:get-prog-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-prog-info(next_id->fd) 0 nsec
test_bpf_obj_id:PASS:check total prog id found by get_next_id 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:check get-map-info(next_id->fd) 0 nsec
test_bpf_obj_id:PASS:get-map-fd(next_id) 0 nsec
test_bpf_obj_id:PASS:check get-map-info(next_id->fd) 0 nsec
test_bpf_obj_id:PASS:check total map id found by get_next_id 0 nsec
test_pkt_md_access:PASS: 277 nsec
Summary: 30 PASSED, 0 FAILED
[root@s8360046 bpf]#

Fixes: 18f3d6be6be1 ("selftests/bpf: Add test cases to test narrower ctx field loads")
Signed-off-by: Thomas Richter 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

bpf: fix byte order test in test_verifier

2017-08-04T23:09:06+00:00

We really must check with #if __BYTE_ORDER == XYZ instead of
just presence of #ifdef __LITTLE_ENDIAN. I noticed that when
actually running this on big endian machine, the latter test
resolves to true for user space, same for #ifdef __BIG_ENDIAN.

E.g., looking at endian.h from libc, both are also defined
there, so we really must test this against __BYTE_ORDER instead
for proper insns selection. For the kernel, such checks are
fine though e.g. see 13da9e200fe4 ("Revert "endian: #define
__BYTE_ORDER"") and 415586c9e6d3 ("UAPI: fix endianness conditionals
in M32R's asm/stat.h") for some more context, but not for
user space. Lets also make sure to properly include endian.h.
After that, suite passes for me:

./test_verifier: ELF 64-bit MSB executable, [...]

Linux foo 4.13.0-rc3+ #4 SMP Fri Aug 4 06:59:30 EDT 2017 s390x s390x s390x GNU/Linux

Before fix: Summary: 505 PASSED, 11 FAILED
After  fix: Summary: 516 PASSED,  0 FAILED

Fixes: 18f3d6be6be1 ("selftests/bpf: Add test cases to test narrower ctx field loads")
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong 
Signed-off-by: David S. Miller

bpf: don't zero out the info struct in bpf_obj_get_info_by_fd()

2017-07-27T00:02:52+00:00

The buffer passed to bpf_obj_get_info_by_fd() should be initialized
to zeros.  Kernel will enforce that to guarantee we can safely extend
info structures in the future.

Making the bpf_obj_get_info_by_fd() call in libbpf perform the zeroing
is problematic, however, since some members of the info structures
may need to be initialized by the callers (for instance pointers
to buffers to which kernel is to dump translated and jited images).

Remove the zeroing and fix up the in-tree callers before any kernel
has been released with this code.

As Daniel points out this seems to be the intended operation anyway,
since commit 95b9afd3987f ("bpf: Test for bpf ID") is itself setting
the buffer pointers before calling bpf_obj_get_info_by_fd().

Signed-off-by: Jakub Kicinski 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

selftests/bpf: subtraction bounds test

2017-07-24T21:02:55+00:00

There is a bug in the verifier's handling of BPF_SUB: [a,b] - [c,d] yields
 was [a-c, b-d] rather than the correct [a-d, b-c].  So here is a test
 which, with the bogus handling, will produce ranges of [0,0] and thus
 allowed accesses; whereas the correct handling will give a range of
 [-255, 255] (and hence the right-shift will give a range of [0, 255]) and
 the accesses will be rejected.

Signed-off-by: Edward Cree 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

bpf: more tests for mixed signed and unsigned bounds checks

2017-07-20T22:20:27+00:00

Add a couple of more test cases to BPF selftests that are related
to mixed signed and unsigned checks.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: add test for mixed signed and unsigned bounds checks

2017-07-20T22:20:27+00:00

These failed due to a bug in verifier bounds handling.

Signed-off-by: Edward Cree 
Acked-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: fix up test cases with mixed signed/unsigned bounds

2017-07-20T22:20:27+00:00

Fix the few existing test cases that used mixed signed/unsigned
bounds and switch them only to one flavor. Reason why we need this
is that proper boundaries cannot be derived from mixed tests.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: allow to specify log level and reduce it for test_verifier

2017-07-20T22:20:27+00:00

For the test_verifier case, it's quite hard to parse log level 2 to
figure out what's causing an issue when used to log level 1. We do
want to use bpf_verify_program() in order to simulate some of the
tests with strict alignment. So just add an argument to pass the level
and put it to 1 for test_verifier.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

samples/bpf: fix a build issue

2017-07-12T03:51:29+00:00

With latest net-next:

====
clang  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include -I./arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated  -I./include -I./arch/x86/include/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h  -Isamples/bpf \
    -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
    -Wno-compare-distinct-pointer-types \
    -Wno-gnu-variable-sized-type-not-at-end \
    -Wno-address-of-packed-member -Wno-tautological-compare \
    -Wno-unknown-warning-option \
    -O2 -emit-llvm -c samples/bpf/tcp_synrto_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/tcp_synrto_kern.o
samples/bpf/tcp_synrto_kern.c:20:10: fatal error: 'bpf_endian.h' file not found
          ^~~~~~~~~~~~~~
1 error generated.
====

net has the same issue.

Add support for ntohl and htonl in tools/testing/selftests/bpf/bpf_endian.h.
Also move bpf_helpers.h from samples/bpf to selftests/bpf and change
compiler include logic so that programs in samples/bpf can access the headers
in selftests/bpf, but not the other way around.

Signed-off-by: Yonghong Song 
Acked-by: Daniel Borkmann 
Acked-by: Lawrence Brakmo 
Signed-off-by: David S. Miller

bpf: add various test cases for verifier selftest

2017-07-03T09:22:52+00:00

Add couple of verifier test cases for x|imm += pkt_ptr, including the
imm += x extension.

Signed-off-by: Daniel Borkmann 
Acked-by: John Fastabend 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller