Commit Graph

22871 Commits

Author SHA1 Message Date
Yonghong Song
7fb5eefd76 selftests/bpf: Fix test_sysctl_loop{1, 2} failure due to clang change
Andrii reported that with latest clang, when building selftests, we have
error likes:
  error: progs/test_sysctl_loop1.c:23:16: in function sysctl_tcp_mem i32 (%struct.bpf_sysctl*):
  Looks like the BPF stack limit of 512 bytes is exceeded.
  Please move large on stack variables into BPF per-cpu array map.

The error is triggered by the following LLVM patch:
  https://reviews.llvm.org/D87134

For example, the following code is from test_sysctl_loop1.c:
  static __always_inline int is_tcp_mem(struct bpf_sysctl *ctx)
  {
    volatile char tcp_mem_name[] = "net/ipv4/tcp_mem/very_very_very_very_long_pointless_string";
    ...
  }
Without the above LLVM patch, the compiler did optimization to load the string
(59 bytes long) with 7 64bit loads, 1 8bit load and 1 16bit load,
occupying 64 byte stack size.

With the above LLVM patch, the compiler only uses 8bit loads, but subregister is 32bit.
So stack requirements become 4 * 59 = 236 bytes. Together with other stuff on
the stack, total stack size exceeds 512 bytes, hence compiler complains and quits.

To fix the issue, removing "volatile" key word or changing "volatile" to
"const"/"static const" does not work, the string is put in .rodata.str1.1 section,
which libbpf did not process it and errors out with
  libbpf: elf: skipping unrecognized data section(6) .rodata.str1.1
  libbpf: prog 'sysctl_tcp_mem': bad map relo against '.L__const.is_tcp_mem.tcp_mem_name'
          in section '.rodata.str1.1'

Defining the string const as global variable can fix the issue as it puts the string constant
in '.rodata' section which is recognized by libbpf. In the future, when libbpf can process
'.rodata.str*.*' properly, the global definition can be changed back to local definition.

Defining tcp_mem_name as a global, however, triggered a verifier failure.
   ./test_progs -n 7/21
  libbpf: load bpf program failed: Permission denied
  libbpf: -- BEGIN DUMP LOG ---
  libbpf:
  invalid stack off=0 size=1
  verification time 6975 usec
  stack depth 160+64
  processed 889 insns (limit 1000000) max_states_per_insn 4 total_states
  14 peak_states 14 mark_read 10

  libbpf: -- END LOG --
  libbpf: failed to load program 'sysctl_tcp_mem'
  libbpf: failed to load object 'test_sysctl_loop2.o'
  test_bpf_verif_scale:FAIL:114
  #7/21 test_sysctl_loop2.o:FAIL
This actually exposed a bpf program bug. In test_sysctl_loop{1,2}, we have code
like
  const char tcp_mem_name[] = "<...long string...>";
  ...
  char name[64];
  ...
  for (i = 0; i < sizeof(tcp_mem_name); ++i)
      if (name[i] != tcp_mem_name[i])
          return 0;
In the above code, if sizeof(tcp_mem_name) > 64, name[i] access may be
out of bound. The sizeof(tcp_mem_name) is 59 for test_sysctl_loop1.c and
79 for test_sysctl_loop2.c.

Without promotion-to-global change, old compiler generates code where
the overflowed stack access is actually filled with valid value, so hiding
the bpf program bug. With promotion-to-global change, the code is different,
more specifically, the previous loading constants to stack is gone, and
"name" occupies stack[-64:0] and overflow access triggers a verifier error.
To fix the issue, adjust "name" buffer size properly.

Reported-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909171542.3673449-1-yhs@fb.com
2020-09-09 11:21:34 -07:00
Yonghong Song
e6054fc1f8 selftests/bpf: Add test for map_ptr arithmetic
Change selftest map_ptr_kern.c with disabling inlining for
one of subtests, which will fail the test without previous
verifier change. Also added to verifier test for both
"map_ptr += scalar" and "scalar += map_ptr" arithmetic.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200908175703.2463721-1-yhs@fb.com
2020-09-08 18:04:07 -07:00
Quentin Monnet
bc0b5a0307 tools, bpf: Synchronise BPF UAPI header with tools
Synchronise the bpf.h header under tools, to report the fixes recently
brought to the documentation for the BPF helpers.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904161454.31135-4-quentin@isovalent.com
2020-09-07 16:31:18 +02:00
Quentin Monnet
1a7581b174 tools: bpftool: Fix formatting in bpftool-link documentation
Fix a formatting error in the documentation for bpftool-link, so that
the man page can build correctly.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904161454.31135-2-quentin@isovalent.com
2020-09-07 16:31:18 +02:00
Andrii Nakryiko
8eb629585d libbpf: Fix potential multiplication overflow
Detected by LGTM static analyze in Github repo, fix potential multiplication
overflow before result is casted to size_t.

Fixes: 8505e8709b ("libbpf: Implement generalized .BTF.ext func/line info adjustment")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904041611.1695163-2-andriin@fb.com
2020-09-04 14:35:12 +02:00
Andrii Nakryiko
17e54b096e libbpf: Fix another __u64 cast in printf
Another issue of __u64 needing either %lu or %llu, depending on the
architecture. Fix with cast to `unsigned long long`.

Fixes: 7e06aad529 ("libbpf: Add multi-prog section support for struct_ops")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904041611.1695163-1-andriin@fb.com
2020-09-04 14:35:12 +02:00
Hao Luo
95cec14b03 selftests/bpf: Fix check in global_data_init.
The returned value of bpf_object__open_file() should be checked with
libbpf_get_error() rather than NULL. This fix prevents test_progs from
crash when test_global_data.o is not present.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200903200528.747884-1-haoluo@google.com
2020-09-03 17:33:31 -07:00
Andrii Nakryiko
ee333df50b selftests/bpf: Add __noinline variant of cls_redirect selftest
As one of the most complicated and close-to-real-world programs, cls_redirect
is a good candidate to exercise libbpf's logic of handling bpf2bpf calls. So
add variant with using explicit __noinline for majority of functions except
few most basic ones. If those few functions are inlined, verifier starts to
complain about program instruction limit of 1mln instructions being exceeded,
most probably due to instruction overhead of doing a sub-program call.
Convert user-space part of selftest to have to sub-tests: with and without
inlining.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200903203542.15944-15-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
baaf680e08 selftests/bpf: Modernize xdp_noinline test w/ skeleton and __noinline
Update xdp_noinline to use BPF skeleton and force __noinline on helper
sub-programs. Also, split existing logic into v4- and v6-only to complicate
sub-program calling patterns (partially overlapped sets of functions for
entry-level BPF programs).

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-14-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
fab45be1d2 selftests/bpf: Add subprogs to pyperf, strobemeta, and l4lb_noinline tests
Add use of non-inlined subprogs to few bigger selftests to excercise libbpf's
bpf2bpf handling logic. Also split l4lb_all selftest into two sub-tests.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-13-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
d86687ae6b selftests/bpf: Turn fexit_bpf2bpf into test with subtests
There are clearly 4 subtests, so make it official.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-12-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
5210958420 libbpf: Deprecate notion of BPF program "title" in favor of "section name"
BPF program title is ambigious and misleading term. It is ELF section name, so
let's just call it that and deprecate bpf_program__title() API in favor of
bpf_program__section_name().

Additionally, using bpf_object__find_program_by_title() is now inherently
dangerous and ambiguous, as multiple BPF program can have the same section
name. So deprecate this API as well and recommend to switch to non-ambiguous
bpf_object__find_program_by_name().

Internally, clean up usage and mis-usage of BPF program section name for
denoting BPF program name. Shorten the field name to prog->sec_name to be
consistent with all other prog->sec_* variables.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-11-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
a7659cc30b selftests/bpf: Don't use deprecated libbpf APIs
Remove all uses of bpf_program__title() and
bpf_program__find_program_by_title().

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-10-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
fd17e272be tools/bpftool: Replace bpf_program__title() with bpf_program__section_name()
bpf_program__title() is deprecated, switch to bpf_program__section_name() and
avoid compilation warnings.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-9-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
a08c02f8d4 selftests/bpf: Add selftest for multi-prog sections and bpf-to-bpf calls
Add a selftest excercising bpf-to-bpf subprogram calls, as well as multiple
entry-point BPF programs per section. Also make sure that BPF CO-RE works for
such set ups both for sub-programs and for multi-entry sections.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-8-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
7e06aad529 libbpf: Add multi-prog section support for struct_ops
Adjust struct_ops handling code to work with multi-program ELF sections
properly.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-7-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
8505e8709b libbpf: Implement generalized .BTF.ext func/line info adjustment
Complete multi-prog sections and multi sub-prog support in libbpf by properly
adjusting .BTF.ext's line and function information. Mark exposed
btf_ext__reloc_func_info() and btf_ext__reloc_func_info() APIs as deprecated.
These APIs have simplistic assumption that all sub-programs are going to be
appended to all main BPF programs, which doesn't hold in real life. It's
unlikely there are any users of this API, as it's very libbpf
internals-specific.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-6-andriin@fb.com
2020-09-03 17:14:40 -07:00
Andrii Nakryiko
c3c556966d libbpf: Make RELO_CALL work for multi-prog sections and sub-program calls
This patch implements general and correct logic for bpf-to-bpf sub-program
calls. Only sub-programs used (called into) from entry-point (main) BPF
program are going to be appended at the end of main BPF program. This ensures
that BPF verifier won't encounter any dead code due to copying unreferenced
sub-program. This change means that each entry-point (main) BPF program might
have a different set of sub-programs appended to it and potentially in
different order. This has implications on how sub-program call relocations
need to be handled, described below.

All relocations are now split into two categores: data references (maps and
global variables) and code references (sub-program calls). This distinction is
important because data references need to be relocated just once per each BPF
program and sub-program. These relocation are agnostic to instruction
locations, because they are not code-relative and they are relocating against
static targets (maps, variables with fixes offsets, etc).

Sub-program RELO_CALL relocations, on the other hand, are highly-dependent on
code position, because they are recorded as instruction-relative offset. So
BPF sub-programs (those that do calls into other sub-programs) can't be
relocated once, they need to be relocated each time such a sub-program is
appended at the end of the main entry-point BPF program. As mentioned above,
each main BPF program might have different subset and differen order of
sub-programs, so call relocations can't be done just once. Splitting data
reference and calls relocations as described above allows to do this
efficiently and cleanly.

bpf_object__find_program_by_name() will now ignore non-entry BPF programs.
Previously one could have looked up '.text' fake BPF program, but the
existence of such BPF program was always an implementation detail and you
can't do much useful with it. Now, though, all non-entry sub-programs get
their own BPF program with name corresponding to a function name, so there is
no more '.text' name for BPF program. This means there is no regression,
effectively, w.r.t.  API behavior. But this is important aspect to highlight,
because it's going to be critical once libbpf implements static linking of BPF
programs. Non-entry static BPF programs will be allowed to have conflicting
names, but global and main-entry BPF program names should be unique. Just like
with normal user-space linking process. So it's important to restrict this
aspect right now, keep static and non-entry functions as internal
implementation details, and not have to deal with regressions in behavior
later.

This patch leaves .BTF.ext adjustment as is until next patch.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200903203542.15944-5-andriin@fb.com
2020-09-03 17:14:39 -07:00
Andrii Nakryiko
db2b8b0642 libbpf: Support CO-RE relocations for multi-prog sections
Fix up CO-RE relocation code to handle relocations against ELF sections
containing multiple BPF programs. This requires lookup of a BPF program by its
section name and instruction index it contains. While it could have been done
as a simple loop, it could run into performance issues pretty quickly, as
number of CO-RE relocations can be quite large in real-world applications, and
each CO-RE relocation incurs BPF program look up now. So instead of simple
loop, implement a binary search by section name + insn offset.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200903203542.15944-4-andriin@fb.com
2020-09-03 17:14:39 -07:00
Andrii Nakryiko
c112239272 libbpf: Parse multi-function sections into multiple BPF programs
Teach libbpf how to parse code sections into potentially multiple bpf_program
instances, based on ELF FUNC symbols. Each BPF program will keep track of its
position within containing ELF section for translating section instruction
offsets into program instruction offsets: regardless of BPF program's location
in ELF section, it's first instruction is always at local instruction offset
0, so when libbpf is working with relocations (which use section-based
instruction offsets) this is critical to make proper translations.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200903203542.15944-3-andriin@fb.com
2020-09-03 17:14:39 -07:00
Andrii Nakryiko
0201c57583 libbpf: Ensure ELF symbols table is found before further ELF processing
libbpf ELF parsing logic might need symbols available before ELF parsing is
completed, so we need to make sure that symbols table section is found in
a separate pass before all the subsequent sections are processed.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200903203542.15944-2-andriin@fb.com
2020-09-03 17:14:39 -07:00
Yonghong Song
858e8b2eb4 selftests/bpf: Test task_file iterator without visiting pthreads
Modified existing bpf_iter_test_file.c program to check whether
all accessed files from the main thread or not.

Modified existing bpf_iter_test_file program to check
whether all accessed files from the main thread or not.
  $ ./test_progs -n 4
  ...
  #4/7 task_file:OK
  ...
  #4 bpf_iter:OK
  Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200902023113.1672863-1-yhs@fb.com
2020-09-02 16:40:33 +02:00
David S. Miller
150f29f5e6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-09-01

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

There are two small conflicts when pulling, resolve as follows:

1) Merge conflict in tools/lib/bpf/libbpf.c between 88a8212028 ("libbpf: Factor
   out common ELF operations and improve logging") in bpf-next and 1e891e513e
   ("libbpf: Fix map index used in error message") in net-next. Resolve by taking
   the hunk in bpf-next:

        [...]
        scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx);
        data = elf_sec_data(obj, scn);
        if (!scn || !data) {
                pr_warn("elf: failed to get %s map definitions for %s\n",
                        MAPS_ELF_SEC, obj->path);
                return -EINVAL;
        }
        [...]

2) Merge conflict in drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c between
   9647c57b11 ("xsk: i40e: ice: ixgbe: mlx5: Test for dma_need_sync earlier for
   better performance") in bpf-next and e20f0dbf20 ("net/mlx5e: RX, Add a prefetch
   command for small L1_CACHE_BYTES") in net-next. Resolve the two locations by retaining
   net_prefetch() and taking xsk_buff_dma_sync_for_cpu() from bpf-next. Should look like:

        [...]
        xdp_set_data_meta_invalid(xdp);
        xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool);
        net_prefetch(xdp->data);
        [...]

We've added 133 non-merge commits during the last 14 day(s) which contain
a total of 246 files changed, 13832 insertions(+), 3105 deletions(-).

The main changes are:

1) Initial support for sleepable BPF programs along with bpf_copy_from_user() helper
   for tracing to reliably access user memory, from Alexei Starovoitov.

2) Add BPF infra for writing and parsing TCP header options, from Martin KaFai Lau.

3) bpf_d_path() helper for returning full path for given 'struct path', from Jiri Olsa.

4) AF_XDP support for shared umems between devices and queues, from Magnus Karlsson.

5) Initial prep work for full BPF-to-BPF call support in libbpf, from Andrii Nakryiko.

6) Generalize bpf_sk_storage map & add local storage for inodes, from KP Singh.

7) Implement sockmap/hash updates from BPF context, from Lorenz Bauer.

8) BPF xor verification for scalar types & add BPF link iterator, from Yonghong Song.

9) Use target's prog type for BPF_PROG_TYPE_EXT prog verification, from Udip Pant.

10) Rework BPF tracing samples to use libbpf loader, from Daniel T. Lee.

11) Fix xdpsock sample to really cycle through all buffers, from Weqaar Janjua.

12) Improve type safety for tun/veth XDP frame handling, from Maciej Żenczykowski.

13) Various smaller cleanups and improvements all over the place.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-01 13:22:59 -07:00
Alexei Starovoitov
f56407fa6e bpf: Remove bpf_lsm_file_mprotect from sleepable list.
Technically the bpf programs can sleep while attached to bpf_lsm_file_mprotect,
but such programs need to access user memory. So they're in might_fault()
category. Which means they cannot be called from file_mprotect lsm hook that
takes write lock on mm->mmap_lock.
Adjust the test accordingly.

Also add might_fault() to __bpf_prog_enter_sleepable() to catch such deadlocks early.

Fixes: 1e6c62a882 ("bpf: Introduce sleepable BPF programs")
Fixes: e68a144547 ("selftests/bpf: Add sleepable tests")
Reported-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200831201651.82447-1-alexei.starovoitov@gmail.com
2020-08-31 23:03:57 +02:00
Magnus Karlsson
2f6324a393 libbpf: Support shared umems between queues and devices
Add support for shared umems between hardware queues and devices to
the AF_XDP part of libbpf. This so that zero-copy can be achieved in
applications that want to send and receive packets between HW queues
on one device or between different devices/netdevs.

In order to create sockets that share a umem between hardware queues
and devices, a new function has been added called
xsk_socket__create_shared(). It takes the same arguments as
xsk_socket_create() plus references to a fill ring and a completion
ring. So for every socket that share a umem, you need to have one more
set of fill and completion rings. This in order to maintain the
single-producer single-consumer semantics of the rings.

You can create all the sockets via the new xsk_socket__create_shared()
call, or create the first one with xsk_socket__create() and the rest
with xsk_socket__create_shared(). Both methods work.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-14-git-send-email-magnus.karlsson@intel.com
2020-08-31 21:15:05 +02:00
Alexei Starovoitov
e68a144547 selftests/bpf: Add sleepable tests
Modify few tests to sanity test sleepable bpf functionality.

Running 'bench trig-fentry-sleep' vs 'bench trig-fentry' and 'perf report':
sleepable with SRCU:
   3.86%  bench     [k] __srcu_read_unlock
   3.22%  bench     [k] __srcu_read_lock
   0.92%  bench     [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
   0.50%  bench     [k] bpf_trampoline_10297
   0.26%  bench     [k] __bpf_prog_exit_sleepable
   0.21%  bench     [k] __bpf_prog_enter_sleepable

sleepable with RCU_TRACE:
   0.79%  bench     [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep
   0.72%  bench     [k] bpf_trampoline_10381
   0.31%  bench     [k] __bpf_prog_exit_sleepable
   0.29%  bench     [k] __bpf_prog_enter_sleepable

non-sleepable with RCU:
   0.88%  bench     [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry
   0.84%  bench     [k] bpf_trampoline_10297
   0.13%  bench     [k] __bpf_prog_enter
   0.12%  bench     [k] __bpf_prog_exit

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-6-alexei.starovoitov@gmail.com
2020-08-28 21:20:33 +02:00
Alexei Starovoitov
2b288740a1 libbpf: Support sleepable progs
Pass request to load program as sleepable via ".s" suffix in the section name.
If it happens in the future that all map types and helpers are allowed with
BPF_F_SLEEPABLE flag "fmod_ret/" and "lsm/" can be aliased to "fmod_ret.s/" and
"lsm.s/" to make all lsm and fmod_ret programs sleepable by default. The fentry
and fexit programs would always need to have sleepable vs non-sleepable
distinction, since not all fentry/fexit progs will be attached to sleepable
kernel functions.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: KP Singh <kpsingh@google.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-5-alexei.starovoitov@gmail.com
2020-08-28 21:20:33 +02:00
Alexei Starovoitov
07be4c4a3e bpf: Add bpf_copy_from_user() helper.
Sleepable BPF programs can now use copy_from_user() to access user memory.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-4-alexei.starovoitov@gmail.com
2020-08-28 21:20:33 +02:00
Alexei Starovoitov
1e6c62a882 bpf: Introduce sleepable BPF programs
Introduce sleepable BPF programs that can request such property for themselves
via BPF_F_SLEEPABLE flag at program load time. In such case they will be able
to use helpers like bpf_copy_from_user() that might sleep. At present only
fentry/fexit/fmod_ret and lsm programs can request to be sleepable and only
when they are attached to kernel functions that are known to allow sleeping.

The non-sleepable programs are relying on implicit rcu_read_lock() and
migrate_disable() to protect life time of programs, maps that they use and
per-cpu kernel structures used to pass info between bpf programs and the
kernel. The sleepable programs cannot be enclosed into rcu_read_lock().
migrate_disable() maps to preempt_disable() in non-RT kernels, so the progs
should not be enclosed in migrate_disable() as well. Therefore
rcu_read_lock_trace is used to protect the life time of sleepable progs.

There are many networking and tracing program types. In many cases the
'struct bpf_prog *' pointer itself is rcu protected within some other kernel
data structure and the kernel code is using rcu_dereference() to load that
program pointer and call BPF_PROG_RUN() on it. All these cases are not touched.
Instead sleepable bpf programs are allowed with bpf trampoline only. The
program pointers are hard-coded into generated assembly of bpf trampoline and
synchronize_rcu_tasks_trace() is used to protect the life time of the program.
The same trampoline can hold both sleepable and non-sleepable progs.

When rcu_read_lock_trace is held it means that some sleepable bpf program is
running from bpf trampoline. Those programs can use bpf arrays and preallocated
hash/lru maps. These map types are waiting on programs to complete via
synchronize_rcu_tasks_trace();

Updates to trampoline now has to do synchronize_rcu_tasks_trace() and
synchronize_rcu_tasks() to wait for sleepable progs to finish and for
trampoline assembly to finish.

This is the first step of introducing sleepable progs. Eventually dynamically
allocated hash maps can be allowed and networking program types can become
sleepable too.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200827220114.69225-3-alexei.starovoitov@gmail.com
2020-08-28 21:20:33 +02:00
Martin KaFai Lau
d557ea39a5 bpf: selftests: Add test for different inner map size
This patch tests the inner map size can be different
for reuseport_sockarray but has to be the same for
arraymap.  A new subtest "diff_size" is added for this.

The existing test is moved to a subtest "lookup_update".

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200828011819.1970825-1-kafai@fb.com
2020-08-28 15:41:30 +02:00
Yonghong Song
b0c9eb3781 bpf: Make bpf_link_info.iter similar to bpf_iter_link_info
bpf_link_info.iter is used by link_query to return bpf_iter_link_info
to user space. Fields may be different, e.g., map_fd vs. map_id, so
we cannot reuse the exact structure. But make them similar, e.g.,

  struct bpf_link_info {
     /* common fields */
     union {
	struct { ... } raw_tracepoint;
	struct { ... } tracing;
	...
	struct {
	    /* common fields for iter */
	    union {
		struct {
		    __u32 map_id;
		} map;
		/* other structs for other targets */
	    };
	};
    };
 };

so the structure is extensible the same way as bpf_iter_link_info.

Fixes: 6b0a249a30 ("bpf: Implement link_query for bpf iterators")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200828051922.758950-1-yhs@fb.com
2020-08-28 14:33:24 +02:00
Jesper Dangaard Brouer
661b37cd43 tools, bpf/build: Cleanup feature files on make clean
The system for "Auto-detecting system features" located under
tools/build/ are (currently) used by perf, libbpf and bpftool. It can
contain stalled feature detection files, which are not cleaned up by
libbpf and bpftool on make clean (side-note: perf tool is correct).

Fix this by making the users invoke the make clean target.

Some details about the changes. The libbpf Makefile already had a
clean-config target (which seems to be copy-pasted from perf), but this
target was not "connected" (a make dependency) to clean target. Choose
not to rename target as someone might be using it. Did change the output
from "CLEAN config" to "CLEAN feature-detect", to make it more clear
what happens.

This is related to the complaint and troubleshooting in the following
link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/
Link: https://lore.kernel.org/bpf/159851841661.1072907.13770213104521805592.stgit@firesoul
2020-08-28 14:04:27 +02:00
Andrii Nakryiko
2e80be60c4 libbpf: Fix compilation warnings for 64-bit printf args
Fix compilation warnings due to __u64 defined differently as `unsigned long`
or `unsigned long long` on different architectures (e.g., ppc64le differs from
x86-64). Also cast one argument to size_t to fix printf warning of similar
nature.

Fixes: eacaaed784 ("libbpf: Implement enum value-based CO-RE relocations")
Fixes: 50e09460d9 ("libbpf: Skip well-known ELF sections when iterating ELF")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200827041109.3613090-1-andriin@fb.com
2020-08-26 22:13:38 -07:00
Yonghong Song
f5493c514c selftests/bpf: Add verifier tests for xor operation
Added some test_verifier bounds check test cases for
xor operations.
  $ ./test_verifier
  ...
  #78/u bounds check for reg = 0, reg xor 1 OK
  #78/p bounds check for reg = 0, reg xor 1 OK
  #79/u bounds check for reg32 = 0, reg32 xor 1 OK
  #79/p bounds check for reg32 = 0, reg32 xor 1 OK
  #80/u bounds check for reg = 2, reg xor 3 OK
  #80/p bounds check for reg = 2, reg xor 3 OK
  #81/u bounds check for reg = any, reg xor 3 OK
  #81/p bounds check for reg = any, reg xor 3 OK
  #82/u bounds check for reg32 = any, reg32 xor 3 OK
  #82/p bounds check for reg32 = any, reg32 xor 3 OK
  #83/u bounds check for reg > 0, reg xor 3 OK
  #83/p bounds check for reg > 0, reg xor 3 OK
  #84/u bounds check for reg32 > 0, reg32 xor 3 OK
  #84/p bounds check for reg32 > 0, reg32 xor 3 OK
  ...

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200825064609.2018077-1-yhs@fb.com
2020-08-26 21:47:32 -07:00
Ido Schimmel
041bc0dce5 selftests: fib_nexthops: Test IPv6 route with group after replacing IPv4 nexthops
Test that an IPv6 route can not use a nexthop group with mixed IPv4 and
IPv6 nexthops, but can use it after replacing the IPv4 nexthops with
IPv6 nexthops.

Output without previous patch:

# ./fib_nexthops.sh -t ipv6_fcnal_runtime

IPv6 functional runtime
-----------------------
TEST: Route add                                                     [ OK ]
TEST: Route delete                                                  [ OK ]
TEST: Ping with nexthop                                             [ OK ]
TEST: Ping - multipath                                              [ OK ]
TEST: Ping - blackhole                                              [ OK ]
TEST: Ping - blackhole replaced with gateway                        [ OK ]
TEST: Ping - gateway replaced by blackhole                          [ OK ]
TEST: Ping - group with blackhole                                   [ OK ]
TEST: Ping - group blackhole replaced with gateways                 [ OK ]
TEST: IPv6 route with device only nexthop                           [ OK ]
TEST: IPv6 multipath route with nexthop mix - dev only + gw         [ OK ]
TEST: IPv6 route can not have a v4 gateway                          [ OK ]
TEST: Nexthop replace - v6 route, v4 nexthop                        [ OK ]
TEST: Nexthop replace of group entry - v6 route, v4 nexthop         [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after removing v4 gateways           [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after replacing v4 gateways          [FAIL]
TEST: Nexthop with default route and rpfilter                       [ OK ]
TEST: Nexthop with multipath default route and rpfilter             [ OK ]

Tests passed:  21
Tests failed:   1

Output with previous patch:

# ./fib_nexthops.sh -t ipv6_fcnal_runtime

IPv6 functional runtime
-----------------------
TEST: Route add                                                     [ OK ]
TEST: Route delete                                                  [ OK ]
TEST: Ping with nexthop                                             [ OK ]
TEST: Ping - multipath                                              [ OK ]
TEST: Ping - blackhole                                              [ OK ]
TEST: Ping - blackhole replaced with gateway                        [ OK ]
TEST: Ping - gateway replaced by blackhole                          [ OK ]
TEST: Ping - group with blackhole                                   [ OK ]
TEST: Ping - group blackhole replaced with gateways                 [ OK ]
TEST: IPv6 route with device only nexthop                           [ OK ]
TEST: IPv6 multipath route with nexthop mix - dev only + gw         [ OK ]
TEST: IPv6 route can not have a v4 gateway                          [ OK ]
TEST: Nexthop replace - v6 route, v4 nexthop                        [ OK ]
TEST: Nexthop replace of group entry - v6 route, v4 nexthop         [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after removing v4 gateways           [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after replacing v4 gateways          [ OK ]
TEST: Nexthop with default route and rpfilter                       [ OK ]
TEST: Nexthop with multipath default route and rpfilter             [ OK ]

Tests passed:  22
Tests failed:   0

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26 16:00:51 -07:00
Ido Schimmel
05290a2773 selftests: fib_nexthops: Test IPv6 route with group after removing IPv4 nexthops
Test that an IPv6 route can not use a nexthop group with mixed IPv4 and
IPv6 nexthops, but can use it after deleting the IPv4 nexthops.

Output without previous patch:

# ./fib_nexthops.sh -t ipv6_fcnal_runtime

IPv6 functional runtime
-----------------------
TEST: Route add                                                     [ OK ]
TEST: Route delete                                                  [ OK ]
TEST: Ping with nexthop                                             [ OK ]
TEST: Ping - multipath                                              [ OK ]
TEST: Ping - blackhole                                              [ OK ]
TEST: Ping - blackhole replaced with gateway                        [ OK ]
TEST: Ping - gateway replaced by blackhole                          [ OK ]
TEST: Ping - group with blackhole                                   [ OK ]
TEST: Ping - group blackhole replaced with gateways                 [ OK ]
TEST: IPv6 route with device only nexthop                           [ OK ]
TEST: IPv6 multipath route with nexthop mix - dev only + gw         [ OK ]
TEST: IPv6 route can not have a v4 gateway                          [ OK ]
TEST: Nexthop replace - v6 route, v4 nexthop                        [ OK ]
TEST: Nexthop replace of group entry - v6 route, v4 nexthop         [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after deleting v4 gateways           [FAIL]
TEST: Nexthop with default route and rpfilter                       [ OK ]
TEST: Nexthop with multipath default route and rpfilter             [ OK ]

Tests passed:  18
Tests failed:   1

Output with previous patch:

bash-5.0# ./fib_nexthops.sh -t ipv6_fcnal_runtime

IPv6 functional runtime
-----------------------
TEST: Route add                                                     [ OK ]
TEST: Route delete                                                  [ OK ]
TEST: Ping with nexthop                                             [ OK ]
TEST: Ping - multipath                                              [ OK ]
TEST: Ping - blackhole                                              [ OK ]
TEST: Ping - blackhole replaced with gateway                        [ OK ]
TEST: Ping - gateway replaced by blackhole                          [ OK ]
TEST: Ping - group with blackhole                                   [ OK ]
TEST: Ping - group blackhole replaced with gateways                 [ OK ]
TEST: IPv6 route with device only nexthop                           [ OK ]
TEST: IPv6 multipath route with nexthop mix - dev only + gw         [ OK ]
TEST: IPv6 route can not have a v4 gateway                          [ OK ]
TEST: Nexthop replace - v6 route, v4 nexthop                        [ OK ]
TEST: Nexthop replace of group entry - v6 route, v4 nexthop         [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route can not have a group with v4 and v6 gateways       [ OK ]
TEST: IPv6 route using a group after deleting v4 gateways           [ OK ]
TEST: Nexthop with default route and rpfilter                       [ OK ]
TEST: Nexthop with multipath default route and rpfilter             [ OK ]

Tests passed:  19
Tests failed:   0

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26 16:00:51 -07:00
Alex Gartrell
ef05afa66c libbpf: Fix unintentional success return code in bpf_object__load
There are code paths where EINVAL is returned directly without setting
errno. In that case, errno could be 0, which would mask the
failure. For example, if a careless programmer set log_level to 10000
out of laziness, they would have to spend a long time trying to figure
out why.

Fixes: 4f33ddb4e3 ("libbpf: Propagate EPERM to caller on program load")
Signed-off-by: Alex Gartrell <alexgartrell@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200826075549.1858580-1-alexgartrell@gmail.com
2020-08-26 15:05:35 -07:00
Udip Pant
1410620cf2 selftests/bpf: Test for map update access from within EXT programs
This adds further tests to ensure access permissions and restrictions
are applied properly for some map types such as sock-map.
It also adds another negative tests to assert static functions cannot be
replaced. In the 'unreliable' mode it still fails with error 'tracing progs
cannot use bpf_spin_lock yet' with the change in the verifier

Signed-off-by: Udip Pant <udippant@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200825232003.2877030-5-udippant@fb.com
2020-08-26 12:47:56 -07:00
Udip Pant
50d19736af selftests/bpf: Test for checking return code for the extended prog
This adds test to enforce same check for the return code for the extended prog
as it is enforced for the target program. It asserts failure for a
return code, which is permitted without the patch in this series, while
it is restricted after the application of this patch.

Signed-off-by: Udip Pant <udippant@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200825232003.2877030-4-udippant@fb.com
2020-08-26 12:47:56 -07:00
Udip Pant
6dc03dc713 selftests/bpf: Add test for freplace program with write access
This adds a selftest that tests the behavior when a freplace target program
attempts to make a write access on a packet. The expectation is that the read or write
access is granted based on the program type of the linked program and
not itself (which is of type, for e.g., BPF_PROG_TYPE_EXT).

This test fails without the associated patch on the verifier.

Signed-off-by: Udip Pant <udippant@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200825232003.2877030-3-udippant@fb.com
2020-08-26 12:47:56 -07:00
Colin Ian King
7100ff7c62 selftests/bpf: Fix spelling mistake "scoket" -> "socket"
There is a spelling mistake in a check error message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200826085907.43095-1-colin.king@canonical.com
2020-08-26 09:19:34 -07:00
Jiri Olsa
d83971761f selftests/bpf: Fix open call in trigger_fstat_events
Alexei reported compile breakage on newer systems with
following error:

  In file included from /usr/include/fcntl.h:290:0,
  4814                 from ./test_progs.h:29,
  4815                 from
  .../bpf-next/tools/testing/selftests/bpf/prog_tests/d_path.c:3:
  4816In function ‘open’,
  4817    inlined from ‘trigger_fstat_events’ at
  .../bpf-next/tools/testing/selftests/bpf/prog_tests/d_path.c:50:10,
  4818    inlined from ‘test_d_path’ at
  .../bpf-next/tools/testing/selftests/bpf/prog_tests/d_path.c:119:6:
  4819/usr/include/x86_64-linux-gnu/bits/fcntl2.h:50:4: error: call to
  ‘__open_missing_mode’ declared with attribute error: open with O_CREAT
  or O_TMPFILE in second argument needs 3 arguments
  4820    __open_missing_mode ();
  4821    ^~~~~~~~~~~~~~~~~~~~~~

We're missing permission bits as 3rd argument
for open call with O_CREAT flag specified.

Fixes: e4d1af4b16 ("selftests/bpf: Add test for d_path helper")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200826101845.747617-1-jolsa@kernel.org
2020-08-26 07:20:48 -07:00
Jiri Olsa
cd04b04de1 selftests/bpf: Add set test to resolve_btfids
Adding test to for sets resolve_btfids. We're checking that
testing set gets properly resolved and sorted.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-15-jolsa@kernel.org
2020-08-25 15:41:15 -07:00
Jiri Olsa
e4d1af4b16 selftests/bpf: Add test for d_path helper
Adding test for d_path helper which is pretty much
copied from Wenbo Zhang's test for bpf_get_fd_path,
which never made it in.

The test is doing fstat/close on several fd types,
and verifies we got the d_path helper working on
kernel probes for vfs_getattr/filp_close functions.

Original-patch-by: Wenbo Zhang <ethercflow@gmail.com>

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-14-jolsa@kernel.org
2020-08-25 15:41:15 -07:00
Jiri Olsa
762f851568 selftests/bpf: Add verifier test for d_path helper
Adding verifier test for attaching tracing program and
calling d_path helper from within and testing that it's
allowed for dentry_open function and denied for 'd_path'
function with appropriate error.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-13-jolsa@kernel.org
2020-08-25 15:41:15 -07:00
Jiri Olsa
6e22ab9da7 bpf: Add d_path helper
Adding d_path helper function that returns full path for
given 'struct path' object, which needs to be the kernel
BTF 'path' object. The path is returned in buffer provided
'buf' of size 'sz' and is zero terminated.

  bpf_d_path(&file->f_path, buf, size);

The helper calls directly d_path function, so there's only
limited set of function it can be called from. Adding just
very modest set for the start.

Updating also bpf.h tools uapi header and adding 'path' to
bpf_helpers_doc.py script.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-11-jolsa@kernel.org
2020-08-25 15:41:15 -07:00
Jiri Olsa
eae2e83e62 bpf: Add BTF_SET_START/END macros
Adding support to define sorted set of BTF ID values.

Following defines sorted set of BTF ID values:

  BTF_SET_START(btf_allowlist_d_path)
  BTF_ID(func, vfs_truncate)
  BTF_ID(func, vfs_fallocate)
  BTF_ID(func, dentry_open)
  BTF_ID(func, vfs_getattr)
  BTF_ID(func, filp_close)
  BTF_SET_END(btf_allowlist_d_path)

It defines following 'struct btf_id_set' variable to access
values and count:

  struct btf_id_set btf_allowlist_d_path;

Adding 'allowed' callback to struct bpf_func_proto, to allow
verifier the check on allowed callers.

Adding btf_id_set_contains function, which will be used by
allowed callbacks to verify the caller's BTF ID value is
within allowed set.

Also removing extra '\' in __BTF_ID_LIST macro.

Added BTF_SET_START_GLOBAL macro for global sets.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-10-jolsa@kernel.org
2020-08-25 15:37:41 -07:00
Jiri Olsa
a5f53b1d59 tools resolve_btfids: Add support for set symbols
The set symbol does not have the unique number suffix,
so we need to give it a special parsing function.

This was omitted in the first batch, because there was
no set support yet, so it slipped in the testing.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-3-jolsa@kernel.org
2020-08-25 15:37:41 -07:00
Jiri Olsa
193a983c5b tools resolve_btfids: Add size check to get_id function
To make sure we don't crash on malformed symbols.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-2-jolsa@kernel.org
2020-08-25 15:37:41 -07:00
KP Singh
cd324d7abb bpf: Add selftests for local_storage
inode_local_storage:

* Hook to the file_open and inode_unlink LSM hooks.
* Create and unlink a temporary file.
* Store some information in the inode's bpf_local_storage during
  file_open.
* Verify that this information exists when the file is unlinked.

sk_local_storage:

* Hook to the socket_post_create and socket_bind LSM hooks.
* Open and bind a socket and set the sk_storage in the
  socket_post_create hook using the start_server helper.
* Verify if the information is set in the socket_bind hook.

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825182919.1118197-8-kpsingh@chromium.org
2020-08-25 15:00:04 -07:00