Commit Graph

28804 Commits

Author SHA1 Message Date
Yonghong Song
f97b8b9bd6 bpftool: Fix a bug in subskeleton code generation
Compiled with clang by adding LLVM=1 both kernel and selftests/bpf
build, I hit the following compilation error:

In file included from /.../tools/testing/selftests/bpf/prog_tests/subskeleton.c:6:
  ./test_subskeleton_lib.subskel.h:168:6: error: variable 'err' is used uninitialized whenever
      'if' condition is true [-Werror,-Wsometimes-uninitialized]
          if (!s->progs)
              ^~~~~~~~~
  ./test_subskeleton_lib.subskel.h:181:11: note: uninitialized use occurs here
          errno = -err;
                   ^~~
  ./test_subskeleton_lib.subskel.h:168:2: note: remove the 'if' if its condition is always false
          if (!s->progs)
          ^~~~~~~~~~~~~~

The compilation error is triggered by the following code
        ...
        int err;

        obj = (struct test_subskeleton_lib *)calloc(1, sizeof(*obj));
        if (!obj) {
                errno = ENOMEM;
                goto err;
        }
        ...

  err:
        test_subskeleton_lib__destroy(obj);
        errno = -err;
        ...
in test_subskeleton_lib__open(). The 'err' is not initialized, yet it
is used in 'errno = -err' later.

The fix is to remove 'errno = -err' since errno has been set properly
in all incoming branches.

Fixes: 00389c58ff ("bpftool: Add support for subskeletons")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220320032009.3106133-1-yhs@fb.com
2022-03-21 14:46:10 -07:00
Hengqi Chen
d0f325c34c libbpf: Close fd in bpf_object__reuse_map
pin_fd is dup-ed and assigned in bpf_map__reuse_fd. Close it
in bpf_object__reuse_map after reuse.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220319030533.3132250-1-hengqi.chen@gmail.com
2022-03-21 15:36:52 +01:00
Yafang Shao
1824d8ea75 bpftool: Fix print error when show bpf map
If there is no btf_id or frozen, it will not show the pids, but the pids don't
depend on any one of them.

Below is the result after this change:

  $ ./bpftool map show
  2: lpm_trie  flags 0x1
	key 8B  value 8B  max_entries 1  memlock 4096B
	pids systemd(1)
  3: lpm_trie  flags 0x1
	key 20B  value 8B  max_entries 1  memlock 4096B
	pids systemd(1)

While before this change, the 'pids systemd(1)' can't be displayed.

Fixes: 9330986c03 ("bpf: Add bloom filter map implementation")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220320060815.7716-1-laoar.shao@gmail.com
2022-03-21 14:58:06 +01:00
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: 6bdd533cee ("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: 2ed0dc5937 ("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 9a69e2b385 ("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: 9a69e2b385 ("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
Andrii Nakryiko
a8fee96202 libbpf: Avoid NULL deref when initializing map BTF info
If BPF object doesn't have an BTF info, don't attempt to search for BTF
types describing BPF map key or value layout.

Fixes: 262cfb74ff ("libbpf: Init btf_{key,value}_type_id on internal map open")
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/20220320001911.3640917-1-andrii@kernel.org
2022-03-20 18:53:04 -07:00
Andrii Nakryiko
08063b4bc1 bpftool: Add BPF_TRACE_KPROBE_MULTI to attach type names table
BPF_TRACE_KPROBE_MULTI is a new attach type name, add it to bpftool's
table. This fixes a currently failing CI bpftool check.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220318150106.2933343-1-andrii@kernel.org
2022-03-18 17:56:00 +01:00
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
Jakub Sitnicki
e06b5bbcf3 selftests/bpf: Use constants for socket states in sock_fields test
Replace magic numbers in BPF code with constants from bpf.h, so that they
don't require an explanation in the comments.

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/20220317113920.1068535-4-jakub@cloudflare.com
2022-03-18 15:46:59 +01:00
Jakub Sitnicki
2d2202ba85 selftests/bpf: Check dst_port only on the client socket
cgroup_skb/egress programs which sock_fields test installs process packets
flying in both directions, from the client to the server, and in reverse
direction.

Recently added dst_port check relies on the fact that destination
port (remote peer port) of the socket which sends the packet is known ahead
of time. This holds true only for the client socket, which connects to the
known server port.

Filter out any traffic that is not egressing from the client socket in the
BPF program that tests reading the dst_port.

Fixes: 8f50f16ff3 ("selftests/bpf: Extend verifier and bpf_sock tests for dst_port loads")
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/20220317113920.1068535-3-jakub@cloudflare.com
2022-03-18 15:46:59 +01:00
Jakub Sitnicki
a4c9fe0ed4 selftests/bpf: Fix error reporting from sock_fields programs
The helper macro that records an error in BPF programs that exercise sock
fields access has been inadvertently broken by adaptation work that
happened in commit b18c1f0aa4 ("bpf: selftest: Adapt sock_fields test to
use skel and global variables").

BPF_NOEXIST flag cannot be used to update BPF_MAP_TYPE_ARRAY. The operation
always fails with -EEXIST, which in turn means the error never gets
recorded, and the checks for errors always pass.

Revert the change in update flags.

Fixes: b18c1f0aa4 ("bpf: selftest: Adapt sock_fields test to use skel and global variables")
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/20220317113920.1068535-2-jakub@cloudflare.com
2022-03-18 15:46:58 +01:00
Delyan Kratunov
3cccbaa033 selftests/bpf: Test subskeleton functionality
This patch changes the selftests/bpf Makefile to also generate
a subskel.h for every skel.h it would have normally generated.

Separately, it also introduces a new subskeleton test which tests
library objects, externs, weak symbols, kconfigs, and user maps.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1bd24956940bbbfe169bb34f7f87b11df52ef011.1647473511.git.delyank@fb.com
2022-03-17 23:12:48 -07:00
Delyan Kratunov
00389c58ff bpftool: Add support for subskeletons
Subskeletons are headers which require an already loaded program to
operate.

For example, when a BPF library is linked into a larger BPF object file,
the library userspace needs a way to access its own global variables
without requiring knowledge about the larger program at build time.

As a result, subskeletons require a loaded bpf_object to open().
Further, they find their own symbols in the larger program by
walking BTF type data at run time.

At this time, programs, maps, and globals are supported through
non-owning pointers.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/ca8a48b4841c72d285ecce82371bef4a899756cb.1647473511.git.delyank@fb.com
2022-03-17 23:12:39 -07:00
Delyan Kratunov
430025e5dc libbpf: Add subskeleton scaffolding
In symmetry with bpf_object__open_skeleton(),
bpf_object__open_subskeleton() performs the actual walking and linking
of maps, progs, and globals described by bpf_*_skeleton objects.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/6942a46fbe20e7ebf970affcca307ba616985b15.1647473511.git.delyank@fb.com
2022-03-17 23:11:16 -07:00
Delyan Kratunov
262cfb74ff libbpf: Init btf_{key,value}_type_id on internal map open
For internal and user maps, look up the key and value btf
types on open() and not load(), so that `bpf_map_btf_value_type_id`
is usable in `bpftool gen`.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/78dbe4e457b4a05e098fc6c8f50014b680c86e4e.1647473511.git.delyank@fb.com
2022-03-17 23:11:15 -07:00
Delyan Kratunov
bc380eb9d0 libbpf: .text routines are subprograms in strict mode
Currently, libbpf considers a single routine in .text to be a program. This
is particularly confusing when it comes to library objects - a single routine
meant to be used as an extern will instead be considered a bpf_program.

This patch hides this compatibility behavior behind the pre-existing
SEC_NAME strict mode flag.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/018de8d0d67c04bf436055270d35d394ba393505.1647473511.git.delyank@fb.com
2022-03-17 23:11:15 -07:00
Jiri Olsa
318c812ceb selftests/bpf: Add cookie test for bpf_program__attach_kprobe_multi_opts
Adding bpf_cookie test for programs attached by
bpf_program__attach_kprobe_multi_opts API.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-14-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
9271a0c7ae selftests/bpf: Add attach test for bpf_program__attach_kprobe_multi_opts
Adding tests for bpf_program__attach_kprobe_multi_opts function,
that test attach with pattern, symbols and addrs.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-13-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
2c6401c966 selftests/bpf: Add kprobe_multi bpf_cookie test
Adding bpf_cookie test for programs attached by kprobe_multi links.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-12-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
f7a11eeccb selftests/bpf: Add kprobe_multi attach test
Adding kprobe_multi attach test that uses new fprobe interface to
attach kprobe program to multiple functions.

The test is attaching programs to bpf_fentry_test* functions and
uses single trampoline program bpf_prog_test_run to trigger
bpf_fentry_test* functions.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-11-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
ddc6b04989 libbpf: Add bpf_program__attach_kprobe_multi_opts function
Adding bpf_program__attach_kprobe_multi_opts function for attaching
kprobe program to multiple functions.

  struct bpf_link *
  bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
                                        const char *pattern,
                                        const struct bpf_kprobe_multi_opts *opts);

User can specify functions to attach with 'pattern' argument that
allows wildcards (*?' supported) or provide symbols or addresses
directly through opts argument. These 3 options are mutually
exclusive.

When using symbols or addresses, user can also provide cookie value
for each symbol/address that can be retrieved later in bpf program
with bpf_get_attach_cookie helper.

  struct bpf_kprobe_multi_opts {
          size_t sz;
          const char **syms;
          const unsigned long *addrs;
          const __u64 *cookies;
          size_t cnt;
          bool retprobe;
          size_t :0;
  };

Symbols, addresses and cookies are provided through opts object
(syms/addrs/cookies) as array pointers with specified count (cnt).

Each cookie value is paired with provided function address or symbol
with the same array index.

The program can be also attached as return probe if 'retprobe' is set.

For quick usage with NULL opts argument, like:

  bpf_program__attach_kprobe_multi_opts(prog, "ksys_*", NULL)

the 'prog' will be attached as kprobe to 'ksys_*' functions.

Also adding new program sections for automatic attachment:

  kprobe.multi/<symbol_pattern>
  kretprobe.multi/<symbol_pattern>

The symbol_pattern is used as 'pattern' argument in
bpf_program__attach_kprobe_multi_opts function.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-10-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
5117c26e87 libbpf: Add bpf_link_create support for multi kprobes
Adding new kprobe_multi struct to bpf_link_create_opts object
to pass multiple kprobe data to link_create attr uapi.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-9-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
85153ac062 libbpf: Add libbpf_kallsyms_parse function
Move the kallsyms parsing in internal libbpf_kallsyms_parse
function, so it can be used from other places.

It will be used in following changes.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-8-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
ca74823c6e bpf: Add cookie support to programs attached with kprobe multi link
Adding support to call bpf_get_attach_cookie helper from
kprobe programs attached with kprobe multi link.

The cookie is provided by array of u64 values, where each
value is paired with provided function address or symbol
with the same array index.

When cookie array is provided it's sorted together with
addresses (check bpf_kprobe_multi_cookie_swap). This way
we can find cookie based on the address in
bpf_get_attach_cookie helper.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-7-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
0dcac27254 bpf: Add multi kprobe link
Adding new link type BPF_LINK_TYPE_KPROBE_MULTI that attaches kprobe
program through fprobe API.

The fprobe API allows to attach probe on multiple functions at once
very fast, because it works on top of ftrace. On the other hand this
limits the probe point to the function entry or return.

The kprobe program gets the same pt_regs input ctx as when it's attached
through the perf API.

Adding new attach type BPF_TRACE_KPROBE_MULTI that allows attachment
kprobe to multiple function with new link.

User provides array of addresses or symbols with count to attach the
kprobe program to. The new link_create uapi interface looks like:

  struct {
          __u32           flags;
          __u32           cnt;
          __aligned_u64   syms;
          __aligned_u64   addrs;
  } kprobe_multi;

The flags field allows single BPF_TRACE_KPROBE_MULTI bit to create
return multi kprobe.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-4-jolsa@kernel.org
2022-03-17 20:17:18 -07:00
Kaixi Fan
e0999c8e59 selftests/bpf: Fix tunnel remote IP comments
In namespace at_ns0, the IP address of tnl dev is 10.1.1.100 which is the
overlay IP, and the ip address of veth0 is 172.16.1.100 which is the vtep
IP. When doing 'ping 10.1.1.100' from root namespace, the remote_ip should
be 172.16.1.100.

Fixes: 933a741e3b ("selftests/bpf: bpf tunnel test.")
Signed-off-by: Kaixi Fan <fankaixi.li@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220313164116.5889-1-fankaixi.li@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-03-17 16:08:02 -07:00
Hou Tao
ad13baf456 selftests/bpf: Test subprog jit when toggle bpf_jit_harden repeatedly
When bpf_jit_harden is toggled between 0 and 2, subprog jit may fail
due to inconsistent twice read values of bpf_jit_harden during jit. So
add a test to ensure the problem is fixed.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220309123321.2400262-5-houtao1@huawei.com
2022-03-16 15:13:36 -07:00
Martin KaFai Lau
82cb2b3077 bpf: selftests: Remove libcap usage from test_progs
This patch removes the libcap usage from test_progs.
bind_perm.c is the only user.  cap_*_effective() helpers added in the
earlier patch are directly used instead.

No other selftest binary is using libcap, so '-lcap' is also removed
from the Makefile.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220316173835.2039334-1-kafai@fb.com
2022-03-16 15:07:49 -07:00
Martin KaFai Lau
b1c2768a82 bpf: selftests: Remove libcap usage from test_verifier
This patch removes the libcap usage from test_verifier.
The cap_*_effective() helpers added in the earlier patch are
used instead.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220316173829.2038682-1-kafai@fb.com
2022-03-16 15:07:49 -07:00
Martin KaFai Lau
663af70aab bpf: selftests: Add helpers to directly use the capget and capset syscall
After upgrading to the newer libcap (>= 2.60),
the libcap commit aca076443591 ("Make cap_t operations thread safe.")
added a "__u8 mutex;" to the "struct _cap_struct".  It caused a few byte
shift that breaks the assumption made in the "struct libcap" definition
in test_verifier.c.

The bpf selftest usage only needs to enable and disable the effective
caps of the running task.  It is easier to directly syscall the
capget and capset instead.  It can also remove the libcap
library dependency.

The cap_helpers.{c,h} is added.  One __u64 is used for all CAP_*
bits instead of two __u32.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220316173823.2036955-1-kafai@fb.com
2022-03-16 15:07:49 -07:00
Daniel Xu
6585abea98 bpftool: man: Add missing top level docs
The top-level (bpftool.8) man page was missing docs for a few
subcommands and their respective sub-sub-commands.

This commit brings the top level man page up to date. Note that I've
kept the ordering of the subcommands the same as in `bpftool help`.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/3049ef5dc509c0d1832f0a8b2dba2ccaad0af688.1647213551.git.dxu@dxuuu.xyz
2022-03-15 15:51:41 -07:00
Dmitrii Dolgov
cbdaf71f7e bpftool: Add bpf_cookie to link output
Commit 82e6b1eee6 ("bpf: Allow to specify user-provided bpf_cookie for
BPF perf links") introduced the concept of user specified bpf_cookie,
which could be accessed by BPF programs using bpf_get_attach_cookie().
For troubleshooting purposes it is convenient to expose bpf_cookie via
bpftool as well, so there is no need to meddle with the target BPF
program itself.

Implemented using the pid iterator BPF program to actually fetch
bpf_cookies, which allows constraining code changes only to bpftool.

$ bpftool link
1: type 7  prog 5
        bpf_cookie 123
        pids bootstrap(81)

Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220309163112.24141-1-9erthalion6@gmail.com
2022-03-15 15:07:27 -07:00
Guo Zhengkui
f98d6dd1e7 selftests/bpf: Clean up array_size.cocci warnings
Clean up the array_size.cocci warnings under tools/testing/selftests/bpf/:

Use `ARRAY_SIZE(arr)` instead of forms like `sizeof(arr)/sizeof(arr[0])`.

tools/testing/selftests/bpf/test_cgroup_storage.c uses ARRAY_SIZE() defined
in tools/include/linux/kernel.h (sys/sysinfo.h -> linux/kernel.h), while
others use ARRAY_SIZE() in bpf_util.h.

Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220315130143.2403-1-guozhengkui@vivo.com
2022-03-15 17:03:10 +01:00
Yonghong Song
d3b351f65b selftests/bpf: Fix a clang compilation error for send_signal.c
Building selftests/bpf with latest clang compiler (clang15 built
from source), I hit the following compilation error:

  /.../prog_tests/send_signal.c:43:16: error: variable 'j' set but not used [-Werror,-Wunused-but-set-variable]
                  volatile int j = 0;
                               ^
  1 error generated.

The problem also exists with clang13 and clang14. clang12 is okay.

In send_signal.c, we have the following code ...

  volatile int j = 0;
  [...]
  for (int i = 0; i < 100000000 && !sigusr1_received; i++)
    j /= i + 1;

... to burn CPU cycles so bpf_send_signal() helper can be tested
in NMI mode.

Slightly changing 'j /= i + 1' to 'j /= i + j + 1' or 'j++' can
fix the problem. Further investigation indicated this should be
a clang bug ([1]). The upstream fix will be proposed later. But it
is a good idea to workaround the issue to unblock people who build
kernel/selftests with clang.

  [1] https://discourse.llvm.org/t/strange-clang-unused-but-set-variable-error-with-volatile-variables/60841

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220311003721.2177170-1-yhs@fb.com
2022-03-11 22:18:13 +01:00
Toke Høiland-Jørgensen
c09df4bd3a selftests/bpf: Add a test for maximum packet size in xdp_do_redirect
This adds an extra test to the xdp_do_redirect selftest for XDP live packet
mode, which verifies that the maximum permissible packet size is accepted
without any errors, and that a too big packet is correctly rejected.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220310225621.53374-2-toke@redhat.com
2022-03-11 22:01:26 +01:00
Roberto Sassu
7bae42b68d selftests/bpf: Check that bpf_kernel_read_file() denies reading IMA policy
Check that bpf_kernel_read_file() denies the reading of an IMA policy, by
ensuring that ima_setup.sh exits with an error.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-10-roberto.sassu@huawei.com
2022-03-10 18:57:55 -08:00
Roberto Sassu
e6dcf7bbf3 selftests/bpf: Add test for bpf_lsm_kernel_read_file()
Test the ability of bpf_lsm_kernel_read_file() to call the sleepable
functions bpf_ima_inode_hash() or bpf_ima_file_hash() to obtain a
measurement of a loaded IMA policy.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-9-roberto.sassu@huawei.com
2022-03-10 18:57:55 -08:00
Roberto Sassu
91e8fa254d selftests/bpf: Check if the digest is refreshed after a file write
Verify that bpf_ima_inode_hash() returns a non-fresh digest after a file
write, and that bpf_ima_file_hash() returns a fresh digest. Verification is
done by requesting the digest from the bprm_creds_for_exec hook, called
before ima_bprm_check().

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-7-roberto.sassu@huawei.com
2022-03-10 18:57:54 -08:00
Roberto Sassu
27a77d0d46 selftests/bpf: Add test for bpf_ima_file_hash()
Add new test to ensure that bpf_ima_file_hash() returns the digest of the
executed files.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-6-roberto.sassu@huawei.com
2022-03-10 18:57:54 -08:00
Roberto Sassu
2746de3c53 selftests/bpf: Move sample generation code to ima_test_common()
Move sample generator code to ima_test_common() so that the new function
can be called by multiple LSM hooks.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-5-roberto.sassu@huawei.com
2022-03-10 18:57:54 -08:00
Roberto Sassu
174b16946e bpf-lsm: Introduce new helper bpf_ima_file_hash()
ima_file_hash() has been modified to calculate the measurement of a file on
demand, if it has not been already performed by IMA or the measurement is
not fresh. For compatibility reasons, ima_inode_hash() remains unchanged.

Keep the same approach in eBPF and introduce the new helper
bpf_ima_file_hash() to take advantage of the modified behavior of
ima_file_hash().

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220302111404.193900-4-roberto.sassu@huawei.com
2022-03-10 18:57:54 -08:00
Chris J Arges
357b3cc3c0 bpftool: Ensure bytes_memlock json output is correct
If a BPF map is created over 2^32 the memlock value as displayed in JSON
format will be incorrect. Use atoll instead of atoi so that the correct
number is displayed.

  ```
  $ bpftool map create /sys/fs/bpf/test_bpfmap type hash key 4 \
    value 1024 entries 4194304 name test_bpfmap
  $ bpftool map list
  1: hash  name test_bpfmap  flags 0x0
          key 4B  value 1024B  max_entries 4194304  memlock 4328521728B
  $ sudo bpftool map list -j | jq .[].bytes_memlock
  33554432
  ```

Signed-off-by: Chris J Arges <carges@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/b6601087-0b11-33cc-904a-1133d1500a10@cloudflare.com
2022-03-11 00:06:11 +01:00
Hengqi Chen
5861701440 bpf: Fix comment for helper bpf_current_task_under_cgroup()
Fix the descriptions of the return values of helper bpf_current_task_under_cgroup().

Fixes: c6b5fb8690 ("bpf: add documentation for eBPF helpers (42-50)")
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220310155335.1278783-1-hengqi.chen@gmail.com
2022-03-10 23:00:43 +01:00
Martin KaFai Lau
3daf0896f3 bpf: selftests: Update tests after s/delivery_time/tstamp/ change in bpf.h
The previous patch made the follow changes:
- s/delivery_time_type/tstamp_type/
- s/bpf_skb_set_delivery_time/bpf_skb_set_tstamp/
- BPF_SKB_DELIVERY_TIME_* to BPF_SKB_TSTAMP_*

This patch is to change the test_tc_dtime.c to reflect the above.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220309090515.3712742-1-kafai@fb.com
2022-03-10 22:57:05 +01:00
Martin KaFai Lau
9bb984f28d bpf: Remove BPF_SKB_DELIVERY_TIME_NONE and rename s/delivery_time_/tstamp_/
This patch is to simplify the uapi bpf.h regarding to the tstamp type
and use a similar way as the kernel to describe the value stored
in __sk_buff->tstamp.

My earlier thought was to avoid describing the semantic and
clock base for the rcv timestamp until there is more clarity
on the use case, so the __sk_buff->delivery_time_type naming instead
of __sk_buff->tstamp_type.

With some thoughts, it can reuse the UNSPEC naming.  This patch first
removes BPF_SKB_DELIVERY_TIME_NONE and also

rename BPF_SKB_DELIVERY_TIME_UNSPEC to BPF_SKB_TSTAMP_UNSPEC
and    BPF_SKB_DELIVERY_TIME_MONO   to BPF_SKB_TSTAMP_DELIVERY_MONO.

The semantic of BPF_SKB_TSTAMP_DELIVERY_MONO is the same:
__sk_buff->tstamp has delivery time in mono clock base.

BPF_SKB_TSTAMP_UNSPEC means __sk_buff->tstamp has the (rcv)
tstamp at ingress and the delivery time at egress.  At egress,
the clock base could be found from skb->sk->sk_clockid.
__sk_buff->tstamp == 0 naturally means NONE, so NONE is not needed.

With BPF_SKB_TSTAMP_UNSPEC for the rcv tstamp at ingress,
the __sk_buff->delivery_time_type is also renamed to __sk_buff->tstamp_type
which was also suggested in the earlier discussion:
https://lore.kernel.org/bpf/b181acbe-caf8-502d-4b7b-7d96b9fc5d55@iogearbox.net/

The above will then make __sk_buff->tstamp and __sk_buff->tstamp_type
the same as its kernel skb->tstamp and skb->mono_delivery_time
counter part.

The internal kernel function bpf_skb_convert_dtime_type_read() is then
renamed to bpf_skb_convert_tstamp_type_read() and it can be simplified
with the BPF_SKB_DELIVERY_TIME_NONE gone.  A BPF_ALU32_IMM(BPF_AND)
insn is also saved by using BPF_JMP32_IMM(BPF_JSET).

The bpf helper bpf_skb_set_delivery_time() is also renamed to
bpf_skb_set_tstamp().  The arg name is changed from dtime
to tstamp also.  It only allows setting tstamp 0 for
BPF_SKB_TSTAMP_UNSPEC and it could be relaxed later
if there is use case to change mono delivery time to
non mono.

prog->delivery_time_access is also renamed to prog->tstamp_type_access.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220309090509.3712315-1-kafai@fb.com
2022-03-10 22:57:05 +01:00
Niklas Söderlund
f655c088e7 bpftool: Restore support for BPF offload-enabled feature probing
Commit 1a56c18e6c ("bpftool: Stop supporting BPF offload-enabled
feature probing") removed the support to probe for BPF offload features.
This is still something that is useful for NFP NIC that can support
offloading of BPF programs.

The reason for the dropped support was that libbpf starting with v1.0
would drop support for passing the ifindex to the BPF prog/map/helper
feature probing APIs. In order to keep this useful feature for NFP
restore the functionality by moving it directly into bpftool.

The code restored is a simplified version of the code that existed in
libbpf which supposed passing the ifindex. The simplification is that it
only targets the cases where ifindex is given and call into libbpf for
the cases where it's not.

Before restoring support for probing offload features:

  # bpftool feature probe dev ens4np0
  Scanning system call availability...
  bpf() syscall is available

  Scanning eBPF program types...

  Scanning eBPF map types...

  Scanning eBPF helper functions...
  eBPF helpers supported for program type sched_cls:
  eBPF helpers supported for program type xdp:

  Scanning miscellaneous eBPF features...
  Large program size limit is NOT available
  Bounded loop support is NOT available
  ISA extension v2 is NOT available
  ISA extension v3 is NOT available

With support for probing offload features restored:

  # bpftool feature probe dev ens4np0
  Scanning system call availability...
  bpf() syscall is available

  Scanning eBPF program types...
  eBPF program_type sched_cls is available
  eBPF program_type xdp is available

  Scanning eBPF map types...
  eBPF map_type hash is available
  eBPF map_type array is available

  Scanning eBPF helper functions...
  eBPF helpers supported for program type sched_cls:
  	- bpf_map_lookup_elem
  	- bpf_get_prandom_u32
  	- bpf_perf_event_output
  eBPF helpers supported for program type xdp:
  	- bpf_map_lookup_elem
  	- bpf_get_prandom_u32
  	- bpf_perf_event_output
  	- bpf_xdp_adjust_head
  	- bpf_xdp_adjust_tail

  Scanning miscellaneous eBPF features...
  Large program size limit is NOT available
  Bounded loop support is NOT available
  ISA extension v2 is NOT available
  ISA extension v3 is NOT available

Signed-off-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220310121846.921256-1-niklas.soderlund@corigine.com
2022-03-10 16:09:47 +01:00
Toke Høiland-Jørgensen
55fcacca36 selftests/bpf: Add selftest for XDP_REDIRECT in BPF_PROG_RUN
This adds a selftest for the XDP_REDIRECT facility in BPF_PROG_RUN, that
redirects packets into a veth and counts them using an XDP program on the
other side of the veth pair and a TC program on the local side of the veth.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-6-toke@redhat.com
2022-03-09 14:19:23 -08:00