2266 Commits

Author SHA1 Message Date
Kumar Kartikeya Dwivedi
792c0a345f selftests/bpf: Add test for strict BTF type check
Ensure that the edge case where first member type was matched
successfully even if it didn't match BTF type of register is caught and
rejected by the verifier.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220424214901.2743946-14-memxor@gmail.com
2022-04-25 20:26:45 -07:00
Kumar Kartikeya Dwivedi
05a945deef selftests/bpf: Add verifier tests for kptr
Reuse bpf_prog_test functions to test the support for PTR_TO_BTF_ID in
BPF map case, including some tests that verify implementation sanity and
corner cases.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220424214901.2743946-13-memxor@gmail.com
2022-04-25 20:26:44 -07:00
Kumar Kartikeya Dwivedi
2cbc469a6f selftests/bpf: Add C tests for kptr
This uses the __kptr and __kptr_ref macros as well, and tries to test
the stuff that is supposed to work, since we have negative tests in
test_verifier suite. Also include some code to test map-in-map support,
such that the inner_map_meta matches the kptr_off_tab of map added as
element.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220424214901.2743946-12-memxor@gmail.com
2022-04-25 20:26:44 -07:00
Kumar Kartikeya Dwivedi
8f14852e89 bpf: Tag argument to be released in bpf_func_proto
Add a new type flag for bpf_arg_type that when set tells verifier that
for a release function, that argument's register will be the one for
which meta.ref_obj_id will be set, and which will then be released
using release_reference. To capture the regno, introduce a new field
release_regno in bpf_call_arg_meta.

This would be required in the next patch, where we may either pass NULL
or a refcounted pointer as an argument to the release function
bpf_kptr_xchg. Just releasing only when meta.ref_obj_id is set is not
enough, as there is a case where the type of argument needed matches,
but the ref_obj_id is set to 0. Hence, we must enforce that whenever
meta.ref_obj_id is zero, the register that is to be released can only
be NULL for a release function.

Since we now indicate whether an argument is to be released in
bpf_func_proto itself, is_release_function helper has lost its utitlity,
hence refactor code to work without it, and just rely on
meta.release_regno to know when to release state for a ref_obj_id.
Still, the restriction of one release argument and only one ref_obj_id
passed to BPF helper or kfunc remains. This may be lifted in the future.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220424214901.2743946-3-memxor@gmail.com
2022-04-25 17:31:35 -07:00
Andrii Nakryiko
fd0493a1e4 selftests/bpf: Switch fexit_stress to bpf_link_create() API
Use bpf_link_create() API in fexit_stress test to attach FEXIT programs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Kui-Feng Lee <kuifeng@fb.com>
Link: https://lore.kernel.org/bpf/20220421033945.3602803-4-andrii@kernel.org
2022-04-23 00:37:02 +02:00
Artem Savkov
c14766a8a8 selftests/bpf: Fix map tests errno checks
Switching to libbpf 1.0 API broke test_lpm_map and test_lru_map as error
reporting changed. Instead of setting errno and returning -1 bpf calls
now return -Exxx directly.
Drop errno checks and look at return code directly.

Fixes: b858ba8c52b6 ("selftests/bpf: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20220421094320.1563570-1-asavkov@redhat.com
2022-04-21 09:51:57 -07:00
Artem Savkov
6a12b8e20d selftests/bpf: Fix prog_tests uprobe_autoattach compilation error
I am getting the following compilation error for prog_tests/uprobe_autoattach.c:

  tools/testing/selftests/bpf/prog_tests/uprobe_autoattach.c: In function ‘test_uprobe_autoattach’:
  ./test_progs.h:209:26: error: pointer ‘mem’ may be used after ‘free’ [-Werror=use-after-free]

The value of mem is now used in one of the asserts, which is why it may be
confusing compilers. However, it is not dereferenced. Silence this by moving
free(mem) after the assert block.

Fixes: 1717e248014c ("selftests/bpf: Uprobe tests should verify param/return values")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220421132317.1583867-1-asavkov@redhat.com
2022-04-21 18:48:04 +02:00
Artem Savkov
920fd5e177 selftests/bpf: Fix attach tests retcode checks
Switching to libbpf 1.0 API broke test_sock and test_sysctl as they
check for return of bpf_prog_attach to be exactly -1. Switch the check
to '< 0' instead.

Fixes: b858ba8c52b6 ("selftests/bpf: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/bpf/20220421130104.1582053-1-asavkov@redhat.com
2022-04-21 16:34:55 +02:00
Liu Jian
127e7dca42 selftests/bpf: Add test for skb_load_bytes
Use bpf_prog_test_run_opts to test the skb_load_bytes function. Tests
the behavior when offset is greater than INT_MAX or a normal value.

Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220416105801.88708-4-liujian56@huawei.com
2022-04-20 23:48:34 +02:00
Kumar Kartikeya Dwivedi
24fe983abe selftests/bpf: Add tests for type tag order validation
Add a few test cases that ensure we catch cases of badly ordered type
tags in modifier chains.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220419164608.1990559-3-memxor@gmail.com
2022-04-19 14:02:49 -07:00
Andrii Nakryiko
0d7fefebea selftests/bpf: Use non-autoloaded programs in few tests
Take advantage of new libbpf feature for declarative non-autoloaded BPF
program SEC() definitions in few test that test single program at a time
out of many available programs within the single BPF object.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220419002452.632125-2-andrii@kernel.org
2022-04-19 13:48:20 -07:00
Yonghong Song
44df171a10 selftests/bpf: Workaround a verifier issue for test exhandler
The llvm patch [1] enabled opaque pointer which caused selftest
'exhandler' failure.
  ...
  ; work = task->task_works;
  7: (79) r1 = *(u64 *)(r6 +2120)       ; R1_w=ptr_callback_head(off=0,imm=0) R6_w=ptr_task_struct(off=0,imm=0)
  ; func = work->func;
  8: (79) r2 = *(u64 *)(r1 +8)          ; R1_w=ptr_callback_head(off=0,imm=0) R2_w=scalar()
  ; if (!work && !func)
  9: (4f) r1 |= r2
  math between ptr_ pointer and register with unbounded min value is not allowed

  below is insn 10 and 11
  10: (55) if r1 != 0 goto +5
  11: (18) r1 = 0 ll
  ...

In llvm, the code generation of 'r1 |= r2' happened in codegen
selectiondag phase due to difference of opaque pointer vs. non-opaque pointer.
Without [1], the related code looks like:
  r2 = *(u64 *)(r6 + 2120)
  r1 = *(u64 *)(r2 + 8)
  if r2 != 0 goto +6 <LBB0_4>
  if r1 != 0 goto +5 <LBB0_4>
  r1 = 0 ll
  ...

I haven't found a good way in llvm to fix this issue. So let us workaround the
problem first so bpf CI won't be blocked.

  [1] https://reviews.llvm.org/D123300

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220419050900.3136024-1-yhs@fb.com
2022-04-19 10:22:19 -07:00
Yonghong Song
8c89b5db7a selftests/bpf: Limit unroll_count for pyperf600 test
LLVM commit [1] changed loop pragma behavior such that
full loop unroll is always honored with user pragma.
Previously, unroll count also depends on the unrolled
code size. For pyperf600, without [1], the loop unroll
count is 150. With [1], the loop unroll count is 600.

The unroll count of 600 caused the program size close to
298k and this caused the following code is generated:
         0:       7b 1a 00 ff 00 00 00 00 *(u64 *)(r10 - 256) = r1
  ;       uint64_t pid_tgid = bpf_get_current_pid_tgid();
         1:       85 00 00 00 0e 00 00 00 call 14
         2:       bf 06 00 00 00 00 00 00 r6 = r0
  ;       pid_t pid = (pid_t)(pid_tgid >> 32);
         3:       bf 61 00 00 00 00 00 00 r1 = r6
         4:       77 01 00 00 20 00 00 00 r1 >>= 32
         5:       63 1a fc ff 00 00 00 00 *(u32 *)(r10 - 4) = r1
         6:       bf a2 00 00 00 00 00 00 r2 = r10
         7:       07 02 00 00 fc ff ff ff r2 += -4
  ;       PidData* pidData = bpf_map_lookup_elem(&pidmap, &pid);
         8:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
        10:       85 00 00 00 01 00 00 00 call 1
        11:       bf 08 00 00 00 00 00 00 r8 = r0
  ;       if (!pidData)
        12:       15 08 15 e8 00 00 00 00 if r8 == 0 goto -6123 <LBB0_27588+0xffffffffffdae100>

Note that insn 12 has a branch offset -6123 which is clearly illegal
and will be rejected by the verifier. The negative offset is due to
the branch range is greater than INT16_MAX.

This patch changed the unroll count to be 150 to avoid above
branch target insn out-of-range issue. Also the llvm is enhanced ([2])
to assert if the branch target insn is out of INT16 range.

  [1] https://reviews.llvm.org/D119148
  [2] https://reviews.llvm.org/D123877

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220419043230.2928530-1-yhs@fb.com
2022-04-19 10:18:56 -07:00
Mykola Lysenko
2324257dbd selftests/bpf: Refactor prog_tests logging and test execution
This is a pre-req to add separate logging for each subtest in
test_progs.

Move all the mutable test data to the test_result struct.
Move per-test init/de-init into the run_one_test function.
Consolidate data aggregation and final log output in
calculate_and_print_summary function.
As a side effect, this patch fixes double counting of errors
for subtests and possible duplicate output of subtest log
on failures.

Also, add prog_tests_framework.c test to verify some of the
counting logic.

As part of verification, confirmed that number of reported
tests is the same before and after the change for both parallel
and sequential test execution.

Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220418222507.1726259-1-mykolal@fb.com
2022-04-18 21:22:13 -07:00
Geliang Tang
f4fd706f73 selftests/bpf: Drop duplicate max/min definitions
Drop duplicate macros min() and MAX() definitions in prog_tests and use
MIN() or MAX() in sys/param.h instead.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/1ae276da9925c2de59b5bdc93b693b4c243e692e.1649462033.git.geliang.tang@suse.com
2022-04-11 17:18:09 +02:00
Yafang Shao
b858ba8c52 selftests/bpf: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK
We have switched to memcg-based memory accouting and thus the rlimit is
not needed any more. LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK was introduced in
libbpf for backward compatibility, so we can use it instead now. After
this change, the header tools/testing/selftests/bpf/bpf_rlimit.h can be
removed.

This patch also removes the useless header sys/resource.h from many files
in tools/testing/selftests/bpf/.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409125958.92629-3-laoar.shao@gmail.com
2022-04-10 20:17:16 -07:00
Mykola Lysenko
61ddff373f selftests/bpf: Improve by-name subtest selection logic in prog_tests
Improve subtest selection logic when using -t/-a/-d parameters.
In particular, more than one subtest can be specified or a
combination of tests / subtests.

-a send_signal -d send_signal/send_signal_nmi* - runs send_signal
test without nmi tests

-a send_signal/send_signal_nmi*,find_vma - runs two send_signal
subtests and find_vma test

-a 'send_signal*' -a find_vma -d send_signal/send_signal_nmi* -
runs 2 send_signal test and find_vma test. Disables two send_signal
nmi subtests

-t send_signal -t find_vma - runs two *send_signal* tests and one
*find_vma* test

This will allow us to have granular control over which subtests
to disable in the CI system instead of disabling whole tests.

Also, add new selftest to avoid possible regression when
changing prog_test test name selection logic.

Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409001750.529930-1-mykolal@fb.com
2022-04-10 20:08:20 -07:00
Jakub Kicinski
34ba23b44c Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-04-09

We've added 63 non-merge commits during the last 9 day(s) which contain
a total of 68 files changed, 4852 insertions(+), 619 deletions(-).

The main changes are:

1) Add libbpf support for USDT (User Statically-Defined Tracing) probes.
   USDTs are an abstraction built on top of uprobes, critical for tracing
   and BPF, and widely used in production applications, from Andrii Nakryiko.

2) While Andrii was adding support for x86{-64}-specific logic of parsing
   USDT argument specification, Ilya followed-up with USDT support for s390
   architecture, from Ilya Leoshkevich.

3) Support name-based attaching for uprobe BPF programs in libbpf. The format
   supported is `u[ret]probe/binary_path:[raw_offset|function[+offset]]`, e.g.
   attaching to libc malloc can be done in BPF via SEC("uprobe/libc.so.6:malloc")
   now, from Alan Maguire.

4) Various load/store optimizations for the arm64 JIT to shrink the image
   size by using arm64 str/ldr immediate instructions. Also enable pointer
   authentication to verify return address for JITed code, from Xu Kuohai.

5) BPF verifier fixes for write access checks to helper functions, e.g.
   rd-only memory from bpf_*_cpu_ptr() must not be passed to helpers that
   write into passed buffers, from Kumar Kartikeya Dwivedi.

6) Fix overly excessive stack map allocation for its base map structure and
   buckets which slipped-in from cleanups during the rlimit accounting removal
   back then, from Yuntao Wang.

7) Extend the unstable CT lookup helpers for XDP and tc/BPF to report netfilter
   connection tracking tuple direction, from Lorenzo Bianconi.

8) Improve bpftool dump to show BPF program/link type names, Milan Landaverde.

9) Minor cleanups all over the place from various others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
  bpf: Fix excessive memory allocation in stack_map_alloc()
  selftests/bpf: Fix return value checks in perf_event_stackmap test
  selftests/bpf: Add CO-RE relos into linked_funcs selftests
  libbpf: Use weak hidden modifier for USDT BPF-side API functions
  libbpf: Don't error out on CO-RE relos for overriden weak subprogs
  samples, bpf: Move routes monitor in xdp_router_ipv4 in a dedicated thread
  libbpf: Allow WEAK and GLOBAL bindings during BTF fixup
  libbpf: Use strlcpy() in path resolution fallback logic
  libbpf: Add s390-specific USDT arg spec parsing logic
  libbpf: Make BPF-side of USDT support work on big-endian machines
  libbpf: Minor style improvements in USDT code
  libbpf: Fix use #ifdef instead of #if to avoid compiler warning
  libbpf: Potential NULL dereference in usdt_manager_attach_usdt()
  selftests/bpf: Uprobe tests should verify param/return values
  libbpf: Improve string parsing for uprobe auto-attach
  libbpf: Improve library identification for uprobe binary path resolution
  selftests/bpf: Test for writes to map key from BPF helpers
  selftests/bpf: Test passing rdonly mem to global func
  bpf: Reject writes for PTR_TO_MAP_KEY in check_helper_mem_access
  bpf: Check PTR_TO_MEM | MEM_RDONLY in check_helper_mem_access
  ...
====================

Link: https://lore.kernel.org/r/20220408231741.19116-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-08 17:07:29 -07:00
Yuntao Wang
658d87687c selftests/bpf: Fix return value checks in perf_event_stackmap test
The bpf_get_stackid() function may also return 0 on success as per UAPI BPF
helper documentation. Therefore, correct checks from 'val > 0' to 'val >= 0'
to ensure that they cover all possible success return values.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220408041452.933944-1-ytcoode@gmail.com
2022-04-08 22:38:17 +02:00
Andrii Nakryiko
8555defe48 selftests/bpf: Add CO-RE relos into linked_funcs selftests
Add CO-RE relocations into __weak subprogs for multi-file linked_funcs
selftest to make sure libbpf handles such combination well.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220408181425.2287230-4-andrii@kernel.org
2022-04-08 22:24:15 +02:00
Alan Maguire
1717e24801 selftests/bpf: Uprobe tests should verify param/return values
uprobe/uretprobe tests don't do any validation of arguments/return values,
and without this we can't be sure we are attached to the right function,
or that we are indeed attached to a uprobe or uretprobe.  To fix this
record argument and return value for auto-attached functions and ensure
these match expectations.  Also need to filter by pid to ensure we do
not pick up stray malloc()s since auto-attach traces libc system-wide.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1649245431-29956-4-git-send-email-alan.maguire@oracle.com
2022-04-07 11:42:51 -07:00
Kumar Kartikeya Dwivedi
9fc4476a08 selftests/bpf: Test for writes to map key from BPF helpers
When invoking bpf_for_each_map_elem callback, we are passed a
PTR_TO_MAP_KEY, previously writes to this through helper may be allowed,
but the fix in previous patches is meant to prevent that case. The test
case tries to pass it as writable memory to helper, and fails test if it
succeeds to pass the verifier.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220319080827.73251-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-04-06 10:32:12 -07:00
Kumar Kartikeya Dwivedi
7cb29b1c99 selftests/bpf: Test passing rdonly mem to global func
Add two test cases, one pass read only map value pointer to global
func, which should be rejected. The same code checks it for kfunc, so
that is covered as well. Second one tries to use the missing check for
PTR_TO_MEM's MEM_RDONLY flag and tries to write to a read only memory
pointer. Without prior patches, both of these tests fail.

Reviewed-by: Hao Luo <haoluo@google.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220319080827.73251-5-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-04-06 10:32:12 -07:00
Artem Savkov
ebaf24c589 selftests/bpf: Use bpf_num_possible_cpus() in per-cpu map allocations
bpf_map_value_size() uses num_possible_cpus() to determine map size, but
some of the tests only allocate enough memory for online cpus. This
results in out-of-bound writes in userspace during bpf(BPF_MAP_LOOKUP_ELEM)
syscalls in cases when number of online cpus is lower than the number of
possible cpus. Fix by switching from get_nprocs_conf() to
bpf_num_possible_cpus() when determining the number of processors in
these tests (test_progs/netcnt and test_cgroup_storage).

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220406085408.339336-1-asavkov@redhat.com
2022-04-06 10:15:53 -07:00
Yuntao Wang
958ddfd75d selftests/bpf: Fix issues in parse_num_list()
The function does not check that parsing_end is false after parsing
argument. Thus, if the final part of the argument is something like '4-',
which is invalid, parse_num_list() will discard it instead of returning
-EINVAL.

Before:

 $ ./test_progs -n 2,4-
 #2 atomic_bounds:OK
 Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED

After:

 $ ./test_progs -n 2,4-
 Failed to parse test numbers.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220406003622.73539-1-ytcoode@gmail.com
2022-04-06 10:10:03 -07:00
Maxim Mikityanskiy
53968dafc4 bpf: Adjust bpf_tcp_check_syncookie selftest to test dual-stack sockets
The previous commit fixed support for dual-stack sockets in
bpf_tcp_check_syncookie. This commit adjusts the selftest to verify the
fixed functionality.

Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Arthur Fabre <afabre@cloudflare.com>
Link: https://lore.kernel.org/bpf/20220406124113.2795730-2-maximmi@nvidia.com
2022-04-06 09:44:45 -07:00
Yuntao Wang
2d0df01974 selftests/bpf: Fix file descriptor leak in load_kallsyms()
Currently, if sym_cnt > 0, it just returns and does not close file, fix it.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220405145711.49543-1-ytcoode@gmail.com
2022-04-05 16:49:32 -07:00
Andrii Nakryiko
00a0fa2d7d selftests/bpf: Add urandom_read shared lib and USDTs
Extend urandom_read helper binary to include USDTs of 4 combinations:
semaphore/semaphoreless (refcounted and non-refcounted) and based in
executable or shared library. We also extend urandom_read with ability
to report it's own PID to parent process and wait for parent process to
ready itself up for tracing urandom_read. We utilize popen() and
underlying pipe properties for proper signaling.

Once urandom_read is ready, we add few tests to validate that libbpf's
USDT attachment handles all the above combinations of semaphore (or lack
of it) and static or shared library USDTs. Also, we validate that libbpf
handles shared libraries both with PID filter and without one (i.e., -1
for PID argument).

Having the shared library case tested with and without PID is important
because internal logic differs on kernels that don't support BPF
cookies. On such older kernels, attaching to USDTs in shared libraries
without specifying concrete PID doesn't work in principle, because it's
impossible to determine shared library's load address to derive absolute
IPs for uprobe attachments. Without absolute IPs, it's impossible to
perform correct look up of USDT spec based on uprobe's absolute IP (the
only kind available from BPF at runtime). This is not the problem on
newer kernels with BPF cookie as we don't need IP-to-ID lookup because
BPF cookie value *is* spec ID.

So having those two situations as separate subtests is good because
libbpf CI is able to test latest selftests against old kernels (e.g.,
4.9 and 5.5), so we'll be able to disable PID-less shared lib attachment
for old kernels, but will still leave PID-specific one enabled to validate
this legacy logic is working correctly.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-8-andrii@kernel.org
2022-04-05 13:16:08 -07:00
Andrii Nakryiko
630301b0d5 selftests/bpf: Add basic USDT selftests
Add semaphore-based USDT to test_progs itself and write basic tests to
valicate both auto-attachment and manual attachment logic, as well as
BPF-side functionality.

Also add subtests to validate that libbpf properly deduplicates USDT
specs and handles spec overflow situations correctly, as well as proper
"rollback" of partially-attached multi-spec USDT.

BPF-side of selftest intentionally consists of two files to validate
that usdt.bpf.h header can be included from multiple source code files
that are subsequently linked into final BPF object file without causing
any symbol duplication or other issues. We are validating that __weak
maps and bpf_usdt_xxx() API functions defined in usdt.bpf.h do work as
intended.

USDT selftests utilize sys/sdt.h header that on Ubuntu systems comes
from systemtap-sdt-devel package. But to simplify everyone's life,
including CI but especially casual contributors to bpf/bpf-next that
are trying to build selftests, I've checked in sys/sdt.h header from [0]
directly. This way it will work on all architectures and distros without
having to figure it out for every relevant combination and adding any
extra implicit package dependencies.

  [0] https://sourceware.org/git?p=systemtap.git;a=blob_plain;f=includes/sys/sdt.h;h=ca0162b4dc57520b96638c8ae79ad547eb1dd3a1;hb=HEAD

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-7-andrii@kernel.org
2022-04-05 13:16:08 -07:00
Ilya Leoshkevich
d298761746 selftests/bpf: Define SYS_NANOSLEEP_KPROBE_NAME for aarch64
attach_probe selftest fails on aarch64 with `failed to create kprobe
'sys_nanosleep+0x0' perf event: No such file or directory`. This is
because, like on several other architectures, nanosleep has a prefix.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20220404142101.27900-1-iii@linux.ibm.com
2022-04-04 14:57:29 -07:00
Quentin Monnet
4eeebce6ac selftests/bpf: Fix parsing of prog types in UAPI hdr for bpftool sync
The script for checking that various lists of types in bpftool remain in
sync with the UAPI BPF header uses a regex to parse enum bpf_prog_type.
If this enum contains a set of values different from the list of program
types in bpftool, it complains.

This script should have reported the addition, some time ago, of the new
BPF_PROG_TYPE_SYSCALL, which was not reported to bpftool's program types
list. It failed to do so, because it failed to parse that new type from
the enum. This is because the new value, in the BPF header, has an
explicative comment on the same line, and the regex does not support
that.

Let's update the script to support parsing enum values when they have
comments on the same line.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220404140944.64744-1-quentin@isovalent.com
2022-04-04 14:46:15 -07:00
Alan Maguire
579c3196b2 selftests/bpf: Add tests for uprobe auto-attach via skeleton
tests that verify auto-attach works for function entry/return for
local functions in program and library functions in a library.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-6-git-send-email-alan.maguire@oracle.com
2022-04-03 19:56:01 -07:00
Alan Maguire
ba7499bc9d selftests/bpf: Add tests for u[ret]probe attach by name
add tests that verify attaching by name for

1. local functions in a program
2. library functions in a shared object

...succeed for uprobe and uretprobes using new "func_name"
option for bpf_program__attach_uprobe_opts().  Also verify
auto-attach works where uprobe, path to binary and function
name are specified, but fails with -EOPNOTSUPP with a SEC
name that does not specify binary path/function.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-5-git-send-email-alan.maguire@oracle.com
2022-04-03 19:56:00 -07:00
Alan Maguire
39f8dc43b7 libbpf: Add auto-attach for uprobes based on section name
Now that u[ret]probes can use name-based specification, it makes
sense to add support for auto-attach based on SEC() definition.
The format proposed is

        SEC("u[ret]probe/binary:[raw_offset|[function_name[+offset]]")

For example, to trace malloc() in libc:

        SEC("uprobe/libc.so.6:malloc")

...or to trace function foo2 in /usr/bin/foo:

        SEC("uprobe//usr/bin/foo:foo2")

Auto-attach is done for all tasks (pid -1).  prog can be an absolute
path or simply a program/library name; in the latter case, we use
PATH/LD_LIBRARY_PATH to resolve the full path, falling back to
standard locations (/usr/bin:/usr/sbin or /usr/lib64:/usr/lib) if
the file is not found via environment-variable specified locations.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-4-git-send-email-alan.maguire@oracle.com
2022-04-03 19:55:57 -07:00
Yuntao Wang
9bbad6dab8 selftests/bpf: Fix cd_flavor_subdir() of test_progs
Currently, when we run test_progs with just executable file name, for
example 'PATH=. test_progs-no_alu32', cd_flavor_subdir() will not check
if test_progs is running as a flavored test runner and switch into
corresponding sub-directory.

This will cause test_progs-no_alu32 executed by the
'PATH=. test_progs-no_alu32' command to run in the wrong directory and
load the wrong BPF objects.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220403135245.1713283-1-ytcoode@gmail.com
2022-04-03 17:01:48 -07:00
Haowen Bai
f6d60facd9 selftests/bpf: Return true/false (not 1/0) from bool functions
Return boolean values ("true" or "false") instead of 1 or 0 from bool
functions.  This fixes the following warnings from coccicheck:

./tools/testing/selftests/bpf/progs/test_xdp_noinline.c:567:9-10: WARNING:
return of 0/1 in function 'get_packet_dst' with return type bool
./tools/testing/selftests/bpf/progs/test_l4lb_noinline.c:221:9-10: WARNING:
return of 0/1 in function 'get_packet_dst' with return type bool

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1648779354-14700-1-git-send-email-baihaowen@meizu.com
2022-04-03 16:42:43 -07:00
Nikolay Borisov
e299bcd4d1 selftests/bpf: Fix vfs_link kprobe definition
Since commit 6521f8917082 ("namei: prepare for idmapped mounts")
vfs_link's prototype was changed, the kprobe definition in
profiler selftest in turn wasn't updated. The result is that all
argument after the first are now stored in different registers. This
means that self-test has been broken ever since. Fix it by updating the
kprobe definition accordingly.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220331140949.1410056-1-nborisov@suse.com
2022-04-03 16:41:24 -07:00
Yauheni Kaliuta
891663ace7 bpf, test_offload.py: Skip base maps without names
The test fails:

  # ./test_offload.py
  [...]
  Test bpftool bound info reporting (own ns)...
  FAIL: 3 BPF maps loaded, expected 2
    File "/root/bpf-next/tools/testing/selftests/bpf/./test_offload.py", line 1177, in <module>
      check_dev_info(False, "")
    File "/root/bpf-next/tools/testing/selftests/bpf/./test_offload.py", line 645, in check_dev_info
      maps = bpftool_map_list(expected=2, ns=ns)
    File "/root/bpf-next/tools/testing/selftests/bpf/./test_offload.py", line 190, in bpftool_map_list
      fail(True, "%d BPF maps loaded, expected %d" %
    File "/root/bpf-next/tools/testing/selftests/bpf/./test_offload.py", line 86, in fail
      tb = "".join(traceback.extract_stack().format())

Some base maps do not have names and they cannot be added due to compatibility
with older kernels, see [0]. So, just skip the unnamed maps.

  [0] https://lore.kernel.org/bpf/CAEf4BzY66WPKQbDe74AKZ6nFtZjq5e+G3Ji2egcVytB9R6_sGQ@mail.gmail.com/

Signed-off-by: Yauheni Kaliuta <ykaliuta@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220329081100.9705-1-ykaliuta@redhat.com
2022-04-01 23:06:19 +02:00
Eyal Birger
fe4625d8b0 selftests/bpf: Remove unused variable from bpf_sk_assign test
Was never used in bpf_sk_assign_test(), and was removed from handle_{tcp,udp}()
in commit 0b9ad56b1ea6 ("selftests/bpf: Use SOCKMAP for server sockets in
bpf_sk_assign test").

Fixes: 0b9ad56b1ea6 ("selftests/bpf: Use SOCKMAP for server sockets in bpf_sk_assign test")
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220329154914.3718658-1-eyal.birger@gmail.com
2022-04-01 22:35:29 +02:00
Martin KaFai Lau
0a210af6d0 bpf: selftests: Test fentry tracing a struct_ops program
This patch tests attaching an fentry prog to a struct_ops prog.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220330011502.2985292-1-kafai@fb.com
2022-03-30 19:31:30 -07:00
Haowen Bai
2609f635a2 selftests/bpf: Fix warning comparing pointer to 0
Avoid pointer type value compared with 0 to make code clear. Reported by
coccicheck:

  tools/testing/selftests/bpf/progs/map_ptr_kern.c:370:21-22:
  WARNING comparing pointer to 0
  tools/testing/selftests/bpf/progs/map_ptr_kern.c:397:21-22:
  WARNING comparing pointer to 0

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1648605588-19269-1-git-send-email-baihaowen@meizu.com
2022-03-30 14:17:25 +02:00
Yonghong Song
ccaff3d56a selftests/bpf: Fix clang compilation errors
llvm upstream patch ([1]) added to issue warning for code like
  void test() {
    int j = 0;
    for (int i = 0; i < 1000; i++)
            j++;
    return;
  }

This triggered several errors in selftests/bpf build since
compilation flag -Werror is used.
  ...
  test_lpm_map.c:212:15: error: variable 'n_matches' set but not used [-Werror,-Wunused-but-set-variable]
        size_t i, j, n_matches, n_matches_after_delete, n_nodes, n_lookups;
                     ^
  test_lpm_map.c:212:26: error: variable 'n_matches_after_delete' set but not used [-Werror,-Wunused-but-set-variable]
        size_t i, j, n_matches, n_matches_after_delete, n_nodes, n_lookups;
                                ^
  ...
  prog_tests/get_stack_raw_tp.c:32:15: error: variable 'cnt' set but not used [-Werror,-Wunused-but-set-variable]
        static __u64 cnt;
                     ^
  ...

  For test_lpm_map.c, 'n_matches'/'n_matches_after_delete' are changed to be volatile
  in order to silent the warning. I didn't remove these two declarations since
  they are referenced in a commented code which might be used by people in certain
  cases. For get_stack_raw_tp.c, the variable 'cnt' is removed.

  [1] https://reviews.llvm.org/D122271

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220325200304.2915588-1-yhs@fb.com
2022-03-28 20:00:11 -07:00
Andrii Nakryiko
99dea2c664 selftests/bpf: fix selftest after random: Urandom_read tracepoint removal
14c174633f34 ("random: remove unused tracepoints") removed all the
tracepoints from drivers/char/random.c, one of which,
random:urandom_read, was used by stacktrace_build_id selftest to trigger
stack trace capture.

Fix breakage by switching to kprobing urandom_read() function.

Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220325225643.2606-1-andrii@kernel.org
2022-03-28 19:09:23 -07:00
Alexei Starovoitov
7f0059b58f selftests/bpf: Fix kprobe_multi test.
When compiler emits endbr insn the function address could
be different than what bpf_get_func_ip() reports.
This is a short term workaround.
bpf_get_func_ip() will be fixed later.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-03-22 11:09:13 -07:00
Hangbin Liu
ec80906b0f selftests/bpf/test_lirc_mode2.sh: Exit with proper code
When test_lirc_mode2_user exec failed, the test report failed but still
exit with 0. Fix it by exiting with an error code.

Another issue is for the LIRCDEV checking. With bash -n, we need to quote
the variable, or it will always be true. So if test_lirc_mode2_user was
not run, just exit with skip code.

Fixes: 6bdd533cee9a ("bpf: add selftest for lirc_mode2 type program")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220321024149.157861-1-liuhangbin@gmail.com
2022-03-21 14:48:06 +01:00
Namhyung Kim
e1cc1f3998 selftests/bpf: Test skipping stacktrace
Add a test case for stacktrace with skip > 0 using a small sized
buffer.  It didn't support skipping entries greater than or equal to
the size of buffer and filled the skipped part with 0.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220314182042.71025-2-namhyung@kernel.org
2022-03-20 19:16:50 -07:00
Jakub Sitnicki
ce52368001 selftests/bpf: Fix test for 4-byte load from remote_port on big-endian
The context access converter rewrites the 4-byte load from
bpf_sk_lookup->remote_port to a 2-byte load from bpf_sk_lookup_kern
structure.

It means that we cannot treat the destination register contents as a 32-bit
value, or the code will not be portable across big- and little-endian
architectures.

This is exactly the same case as with 4-byte loads from bpf_sock->dst_port
so follow the approach outlined in [1] and treat the register contents as a
16-bit value in the test.

[1]: https://lore.kernel.org/bpf/20220317113920.1068535-5-jakub@cloudflare.com/

Fixes: 2ed0dc5937d3 ("selftests/bpf: Cover 4-byte load from remote_port in bpf_sk_lookup")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220319183356.233666-4-jakub@cloudflare.com
2022-03-20 18:59:00 -07:00
Jakub Sitnicki
3c69611b89 selftests/bpf: Fix u8 narrow load checks for bpf_sk_lookup remote_port
In commit 9a69e2b385f4 ("bpf: Make remote_port field in struct
bpf_sk_lookup 16-bit wide") ->remote_port field changed from __u32 to
__be16.

However, narrow load tests which exercise 1-byte sized loads from
offsetof(struct bpf_sk_lookup, remote_port) were not adopted to reflect the
change.

As a result, on little-endian we continue testing loads from addresses:

 - (__u8 *)&ctx->remote_port + 3
 - (__u8 *)&ctx->remote_port + 4

which map to the zero padding following the remote_port field, and don't
break the tests because there is no observable change.

While on big-endian, we observe breakage because tests expect to see zeros
for values loaded from:

 - (__u8 *)&ctx->remote_port - 1
 - (__u8 *)&ctx->remote_port - 2

Above addresses map to ->remote_ip6 field, which precedes ->remote_port,
and are populated during the bpf_sk_lookup IPv6 tests.

Unsurprisingly, on s390x we observe:

  #136/38 sk_lookup/narrow access to ctx v4:OK
  #136/39 sk_lookup/narrow access to ctx v6:FAIL

Fix it by removing the checks for 1-byte loads from offsets outside of the
->remote_port field.

Fixes: 9a69e2b385f4 ("bpf: Make remote_port field in struct bpf_sk_lookup 16-bit wide")
Suggested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220319183356.233666-3-jakub@cloudflare.com
2022-03-20 18:58:59 -07:00
Joanne Koong
0e790cbb1a selftests/bpf: Test for associating multiple elements with the local storage
This patch adds a few calls to the existing local storage selftest to
test that we can associate multiple elements with the local storage.

The sleepable program's call to bpf_sk_storage_get with sk_storage_map2
will lead to an allocation of a new selem under the GFP_KERNEL flag.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220318045553.3091807-3-joannekoong@fb.com
2022-03-20 18:55:05 -07:00
Jakub Sitnicki
deb5940046 selftests/bpf: Fix test for 4-byte load from dst_port on big-endian
The check for 4-byte load from dst_port offset into bpf_sock is failing on
big-endian architecture - s390. The bpf access converter rewrites the
4-byte load to a 2-byte load from sock_common at skc_dport offset, as shown
below.

  * s390 / llvm-objdump -S --no-show-raw-insn

  00000000000002a0 <sk_dst_port__load_word>:
        84:       r1 = *(u32 *)(r1 + 48)
        85:       w0 = 1
        86:       if w1 == 51966 goto +1 <LBB5_2>
        87:       w0 = 0
  00000000000002c0 <LBB5_2>:
        88:       exit

  * s390 / bpftool prog dump xlated

  _Bool sk_dst_port__load_word(struct bpf_sock * sk):
    35: (69) r1 = *(u16 *)(r1 +12)
    36: (bc) w1 = w1
    37: (b4) w0 = 1
    38: (16) if w1 == 0xcafe goto pc+1
    39: (b4) w0 = 0
    40: (95) exit

  * x86_64 / llvm-objdump -S --no-show-raw-insn

  00000000000002a0 <sk_dst_port__load_word>:
        84:       r1 = *(u32 *)(r1 + 48)
        85:       w0 = 1
        86:       if w1 == 65226 goto +1 <LBB5_2>
        87:       w0 = 0
  00000000000002c0 <LBB5_2>:
        88:       exit

  * x86_64 / bpftool prog dump xlated

  _Bool sk_dst_port__load_word(struct bpf_sock * sk):
    33: (69) r1 = *(u16 *)(r1 +12)
    34: (b4) w0 = 1
    35: (16) if w1 == 0xfeca goto pc+1
    36: (b4) w0 = 0
    37: (95) exit

This leads to surprises if we treat the destination register contents as a
32-bit value, ignoring the fact that in reality it contains a 16-bit value.

On little-endian the register contents reflect the bpf_sock struct
definition, where the lower 16-bits contain the port number:

	struct bpf_sock {
		...
		__be16 dst_port;	/* offset 48 */
		__u16 :16;
		...
	};

However, on big-endian the register contents suggest that field the layout
of bpf_sock struct is as so:

	struct bpf_sock {
		...
		__u16 :16;		/* offset 48 */
		__be16 dst_port;
		...
	};

Account for this quirky access conversion in the test case exercising the
4-byte load by treating the result as 16-bit wide.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220317113920.1068535-5-jakub@cloudflare.com
2022-03-18 15:46:59 +01:00