linux-stable.git/tools/testing/selftests/bpf, branch linux-5.0.y

selftests/bpf: ksym_search won't check symbols exists

2019-05-31T13:45:10+00:00

[ Upstream commit 0979ff7992fb6f4eb837995b12f4071dcafebd2d ]

Currently, ksym_search located at trace_helpers won't check symbols are
existing or not.

In ksym_search, when symbol is not found, it will return &syms[0](_stext).
But when the kernel symbols are not loaded, it will return NULL, which is
not a desired action.

This commit will add verification logic whether symbols are loaded prior
to the symbol search.

Signed-off-by: Daniel T. Lee 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Sasha Levin

selftests/bpf: set RLIMIT_MEMLOCK properly for test_libbpf_open.c

2019-05-31T13:44:52+00:00

[ Upstream commit 6cea33701eb024bc6c920ab83940ee22afd29139 ]

Test test_libbpf.sh failed on my development server with failure
  -bash-4.4$ sudo ./test_libbpf.sh
  [0] libbpf: Error in bpf_object__probe_name():Operation not permitted(1).
      Couldn't load basic 'r0 = 0' BPF program.
  test_libbpf: failed at file test_l4lb.o
  selftests: test_libbpf [FAILED]
  -bash-4.4$

The reason is because my machine has 64KB locked memory by default which
is not enough for this program to get locked memory.
Similar to other bpf selftests, let us increase RLIMIT_MEMLOCK
to infinity, which fixed the issue.

Signed-off-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

selftests/bpf: suppress readelf stderr when probing for BTF support

2019-04-05T20:34:48+00:00

[ Upstream commit 2f0921262ba943fe9d9f59037a033927d8c4789b ]

Before:
$ make -s -C tools/testing/selftests/bpf
readelf: Error: Missing knowledge of 32-bit reloc types used in DWARF
sections of machine number 247
readelf: Warning: unable to apply unsupported reloc type 10 to section
.debug_info
readelf: Warning: unable to apply unsupported reloc type 1 to section
.debug_info
readelf: Warning: unable to apply unsupported reloc type 10 to section
.debug_info

After:
$ make -s -C tools/testing/selftests/bpf

v2:
* use llvm-readelf instead of redirecting binutils' readelf stderr to
  /dev/null

Signed-off-by: Stanislav Fomichev 
Acked-by: Song Liu 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Sasha Levin

selftests/bpf: skip verifier tests for unsupported program types

2019-04-05T20:34:45+00:00

[ Upstream commit 8184d44c9a577a2f1842ed6cc844bfd4a9981d8e ]

Use recently introduced bpf_probe_prog_type() to skip tests in the
test_verifier() if bpf_verify_program() fails. The skipped test is
indicated in the output.

Example:

...
679/p bpf_get_stack return R0 within range SKIP (unsupported program
type 5)
680/p ld_abs: invalid op 1 OK
...
Summary: 863 PASSED, 165 SKIPPED, 3 FAILED

Signed-off-by: Stanislav Fomichev 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Sasha Levin

bpf: test_maps: fix possible out of bound access warning

2019-04-05T20:34:42+00:00

[ Upstream commit dd9cef43c222df7c0d76d34451808e789952379d ]

When compiling test_maps selftest with GCC-8, it warns that an array
might be indexed with a negative value, which could cause a negative
out of bound access, depending on parameters of the function. This
is the GCC-8 warning:

	gcc -Wall -O2 -I../../../include/uapi -I../../../lib -I../../../lib/bpf -I../../../../include/generated -DHAVE_GENHDR -I../../../include    test_maps.c /home/breno/Devel/linux/tools/testing/selftests/bpf/libbpf.a -lcap -lelf -lrt -lpthread -o /home/breno/Devel/linux/tools/testing/selftests/bpf/test_maps
	In file included from test_maps.c:16:
	test_maps.c: In function ‘run_all_tests’:
	test_maps.c:1079:10: warning: array subscript -1 is below array bounds of ‘pid_t[ + 1]’ [-Warray-bounds]
	   assert(waitpid(pid[i], &status, 0) == pid[i]);
		  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
	test_maps.c:1059:6: warning: array subscript -1 is below array bounds of ‘pid_t[ + 1]’ [-Warray-bounds]
	   pid[i] = fork();
	   ~~~^~~

This patch simply guarantees that the task(s) variables are unsigned,
thus, they could never be a negative number (which they are not in
current code anyway), hence avoiding an out of bound access warning.

Signed-off-by: Breno Leitao 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Sasha Levin

tools/bpf: selftests: add map lookup to test_map_in_map bpf prog

2019-04-05T20:34:27+00:00

[ Upstream commit 9eca5083757b679b37f210092c871916c2c222d0 ]

The bpf_map_lookup_elem is added in the bpf program.
Without previous patch, the test change will trigger the
following error:
  $ ./test_maps
  ...
  ; value_p = bpf_map_lookup_elem(map, &key);
  20: (bf) r1 = r7
  21: (bf) r2 = r8
  22: (85) call bpf_map_lookup_elem#1
  ; if (!value_p || *value_p != 123)
  23: (15) if r0 == 0x0 goto pc+16
   R0=map_value(id=2,off=0,ks=4,vs=4,imm=0) R6=inv1 R7=map_ptr(id=0,off=0,ks=4,vs=4,imm=0)
   R8=fp-8,call_-1 R10=fp0,call_-1 fp-8=mmmmmmmm
  ; if (!value_p || *value_p != 123)
  24: (61) r1 = *(u32 *)(r0 +0)
   R0=map_value(id=2,off=0,ks=4,vs=4,imm=0) R6=inv1 R7=map_ptr(id=0,off=0,ks=4,vs=4,imm=0)
   R8=fp-8,call_-1 R10=fp0,call_-1 fp-8=mmmmmmmm
  bpf_spin_lock cannot be accessed directly by load/store

With the kernel fix in the previous commit, the error goes away.

Signed-off-by: Yonghong Song 
Acked-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

bpf, lpm: fix lookup bug in map_delete_elem

2019-02-22T15:17:53+00:00

trie_delete_elem() was deleting an entry even though it was not matching
if the prefixlen was correct. This patch adds a check on matchlen.

Reproducer:

$ sudo bpftool map create /sys/fs/bpf/mylpm type lpm_trie key 8 value 1 entries 128 name mylpm flags 1
$ sudo bpftool map update pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 aa bb cc dd value hex 01
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
key: 10 00 00 00 aa bb cc dd  value: 01
Found 1 element
$ sudo bpftool map delete pinned /sys/fs/bpf/mylpm key hex 10 00 00 00 ff ff ff ff
$ echo $?
0
$ sudo bpftool map dump pinned /sys/fs/bpf/mylpm
Found 0 elements

A similar reproducer is added in the selftests.

Without the patch:

$ sudo ./tools/testing/selftests/bpf/test_lpm_map
test_lpm_map: test_lpm_map.c:485: test_lpm_delete: Assertion `bpf_map_delete_elem(map_fd, key) == -1 && errno == ENOENT' failed.
Aborted

With the patch: test_lpm_map runs without errors.

Fixes: e454cf595853 ("bpf: Implement map_delete_elem for BPF_MAP_TYPE_LPM_TRIE")
Cc: Craig Gallek 
Signed-off-by: Alban Crequy 
Acked-by: Craig Gallek 
Signed-off-by: Daniel Borkmann

bpf, selftests: fix handling of sparse CPU allocations

2019-01-31T22:13:22+00:00

Previously, bpf_num_possible_cpus() had a bug when calculating a
number of possible CPUs in the case of sparse CPU allocations, as
it was considering only the first range or element of
/sys/devices/system/cpu/possible.

E.g. in the case of "0,2-3" (CPU 1 is not available), the function
returned 1 instead of 3.

This patch fixes the function by making it parse all CPU ranges and
elements.

Signed-off-by: Martynas Pumputis 
Acked-by: Yonghong Song 
Signed-off-by: Daniel Borkmann

tools/bpf: fix test_btf for typedef func_proto case

2019-01-30T03:15:32+00:00

Fixed one test_btf raw test such that typedef func_proto
is permitted now.

Fixes: 78a2540e8945 ("tools/bpf: Add tests for BTF_KIND_FUNC_PROTO and BTF_KIND_FUNC")
Acked-by: Martin KaFai Lau 
Signed-off-by: Yonghong Song 
Signed-off-by: Alexei Starovoitov

selftests/bpf: retry tests that expect build-id

2019-01-17T15:43:18+00:00

While running test_progs in a loop I found out that I'm sometimes hitting
"Didn't find expected build ID from the map" error.

Looking at stack_map_get_build_id_offset() it seems that it is racy (by
design) and can sometimes return BPF_STACK_BUILD_ID_IP (i.e. can't trylock
current->mm->mmap_sem).

Let's retry this test a single time.

Fixes: 13790d1cc72c ("bpf: add selftest for stackmap with build_id in NMI context")
Acked-by: Song Liu 
Signed-off-by: Stanislav Fomichev 
Signed-off-by: Daniel Borkmann