Commit Graph

1832 Commits

Author SHA1 Message Date
thiagoftsm
dac1c4b6a8 Merge branch 'libbpf:master' into master v1.0.1_netdatta v1.0.1_netdata 2022-09-29 21:37:39 +00:00
Andrii Nakryiko
1714037104 vmtest: regenerate latest vmlinux.h
Update checked in vmlinux.h for 5.5 kernel tests.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
d598cb20c7 libbpf: bump version to 1.1.0
Bump LIBBPF_MINOR_VERSION to 1 for v1.1.0.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
ce321d6fd4 sync: latest libbpf changes from kernel
Syncing latest libbpf commits from kernel repository.
Baseline bpf-next commit:   e34cfee65ec891a319ce79797dda18083af33a76
Checkpoint bpf-next commit: 87dbdc230d162bf9ee1ac77c8ade178b6b1e199e
Baseline bpf commit:        14b20b784f59bdd95f6f1cfb112c9818bcec4d84
Checkpoint bpf commit:      60240bc26114543fcbfcd8a28466e67e77b20388

Andrii Nakryiko (3):
  libbpf: Fix crash if SEC("freplace") programs don't have
    attach_prog_fd set
  libbpf: restore memory layout of bpf_object_open_opts
  libbpf: Don't require full struct enum64 in UAPI headers

Benjamin Tissoires (1):
  libbpf: add map_get_fd_by_id and map_delete_elem in light skeleton

Daniel Borkmann (1):
  libbpf: Remove gcc support for bpf_tail_call_static for now

David Vernet (3):
  bpf: Define new BPF_MAP_TYPE_USER_RINGBUF map type
  bpf: Add bpf_user_ringbuf_drain() helper
  bpf: Add libbpf logic for user-space ring buffer

Hao Luo (2):
  bpf: Introduce cgroup iter
  bpf: Add CGROUP prefix to cgroup_iter_order

James Hilliard (1):
  libbpf: Add GCC support for bpf_tail_call_static

Jiri Olsa (1):
  bpf: Return value in kprobe get_func_ip only for entry address

Jon Doron (1):
  libbpf: Fix the case of running as non-root with capabilities

Pu Lehui (1):
  bpf, cgroup: Reject prog_attach_flags array when effective query

Quentin Monnet (1):
  bpf: Fix a few typos in BPF helpers documentation

Shmulik Ladkani (2):
  bpf, flow_dissector: Introduce BPF_FLOW_DISSECTOR_CONTINUE retcode for
    bpf progs
  bpf: Support getting tunnel flags

Stanislav Fomichev (1):
  bpf: update bpf_{g,s}et_retval documentation

Tao Chen (1):
  libbpf: Support raw BTF placed in the default search path

Wang Yufen (1):
  libbpf: Add pathname_concat() helper

Xin Liu (2):
  libbpf: Clean up legacy bpf maps declaration in bpf_helpers
  libbpf: Fix NULL pointer exception in API btf_dump__dump_type_data

Yonghong Song (3):
  bpf: Update descriptions for helpers bpf_get_func_arg[_cnt]()
  libbpf: Add new BPF_PROG2 macro
  libbpf: Improve BPF_PROG2 macro code quality and description

 include/uapi/linux/bpf.h | 139 +++++++++++++++++---
 src/bpf_helpers.h        |  12 --
 src/bpf_tracing.h        | 107 ++++++++++++++++
 src/btf.c                |  32 ++---
 src/btf.h                |  25 +++-
 src/btf_dump.c           |   2 +-
 src/libbpf.c             | 106 ++++++++-------
 src/libbpf.h             | 111 +++++++++++++++-
 src/libbpf.map           |  10 ++
 src/libbpf_probes.c      |   1 +
 src/libbpf_version.h     |   2 +-
 src/ringbuf.c            | 271 +++++++++++++++++++++++++++++++++++++++
 src/skel_internal.h      |  23 ++++
 src/usdt.c               |   2 +-
 14 files changed, 731 insertions(+), 112 deletions(-)

--
2.30.2
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
0f5b3a10ae sync: auto-generate latest BPF helpers
Latest changes to BPF helper definitions.
2022-09-27 15:23:45 -07:00
Pu Lehui
5859c59e50 bpf, cgroup: Reject prog_attach_flags array when effective query
Attach flags is only valid for attached progs of this layer cgroup,
but not for effective progs. For querying with EFFECTIVE flags,
exporting attach flags does not make sense. So when effective query,
we reject prog_attach_flags array and don't need to populate it.
Also we limit attach_flags to output 0 during effective query.

Fixes: b79c9fc9551b ("bpf: implement BPF_PROG_QUERY for BPF_LSM_CGROUP")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://lore.kernel.org/r/20220921104604.2340580-2-pulehui@huaweicloud.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
85f8b7c4dc libbpf: Don't require full struct enum64 in UAPI headers
Drop the requirement for system-wide kernel UAPI headers to provide full
struct btf_enum64 definition. This is an unexpected requirement that
slipped in libbpf 1.0 and put unnecessary pressure ([0]) on users to have
a bleeding-edge kernel UAPI header from unreleased Linux 6.0.

To achieve this, we forward declare struct btf_enum64. But that's not
enough as there is btf_enum64_value() helper that expects to know the
layout of struct btf_enum64. So we get a bit creative with
reinterpreting memory layout as array of __u32 and accesing lo32/hi32
fields as array elements. Alternative way would be to have a local
pointer variable for anonymous struct with exactly the same layout as
struct btf_enum64, but that gets us into C++ compiler errors complaining
about invalid type casts. So play it safe, if ugly.

  [0] Closes: https://github.com/libbpf/libbpf/issues/562

Fixes: d90ec262b35b ("libbpf: Add enum64 support for btf_dump")
Reported-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/bpf/20220927042940.147185-1-andrii@kernel.org
2022-09-27 15:23:45 -07:00
Jon Doron
9da0dcb621 libbpf: Fix the case of running as non-root with capabilities
When running rootless with special capabilities like:
FOWNER / DAC_OVERRIDE / DAC_READ_SEARCH

The "access" API will not make the proper check if there is really
access to a file or not.

>From the access man page:
"
The check is done using the calling process's real UID and GID, rather
than the effective IDs as is done when actually attempting an operation
(e.g., open(2)) on the file.  Similarly, for the root user, the check
uses the set of permitted capabilities  rather than the set of effective
capabilities; ***and for non-root users, the check uses an empty set of
capabilities.***
"

What that means is that for non-root user the access API will not do the
proper validation if the process really has permission to a file or not.

To resolve this this patch replaces all the access API calls with
faccessat with AT_EACCESS flag.

Signed-off-by: Jon Doron <jond@wiz.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220925070431.1313680-1-arilou@gmail.com
2022-09-27 15:23:45 -07:00
Jiri Olsa
82c4054376 bpf: Return value in kprobe get_func_ip only for entry address
Changing return value of kprobe's version of bpf_get_func_ip
to return zero if the attach address is not on the function's
entry point.

For kprobes attached in the middle of the function we can't easily
get to the function address especially now with the CONFIG_X86_KERNEL_IBT
support.

If user cares about current IP for kprobes attached within the
function body, they can get it with PT_REGS_IP(ctx).

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20220926153340.1621984-6-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
b3a117773d libbpf: restore memory layout of bpf_object_open_opts
When attach_prog_fd field was removed in libbpf 1.0 and replaced with
`long: 0` placeholder, it actually shifted all the subsequent fields by
8 byte. This is due to `long: 0` promising to adjust next field's offset
to long-aligned offset. But in this case we were already long-aligned
as pin_root_path is a pointer. So `long: 0` had no effect, and thus
didn't feel the gap created by removed attach_prog_fd.

Non-zero bitfield should have been used instead. I validated using
pahole. Originally kconfig field was at offset 40. With `long: 0` it's
at offset 32, which is wrong. With this change it's back at offset 40.

While technically libbpf 1.0 is allowed to break backwards
compatibility and applications should have been recompiled against
libbpf 1.0 headers, but given how trivial it is to preserve memory
layout, let's fix this.

Reported-by: Grant Seltzer Richman <grantseltzer@gmail.com>
Fixes: 146bf811f5ac ("libbpf: remove most other deprecated high-level APIs")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220923230559.666608-1-andrii@kernel.org
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-09-27 15:23:45 -07:00
Wang Yufen
fc2577c54c libbpf: Add pathname_concat() helper
Move snprintf and len check to common helper pathname_concat() to make the
code simpler.

Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1663828124-10437-1-git-send-email-wangyufen@huawei.com
2022-09-27 15:23:45 -07:00
Tao Chen
0420f75dbc libbpf: Support raw BTF placed in the default search path
Currently, the default vmlinux files at '/boot/vmlinux-*',
'/lib/modules/*/vmlinux-*' etc. are parsed with 'btf__parse_elf()' to
extract BTF. It is possible that these files are actually raw BTF files
similar to /sys/kernel/btf/vmlinux. So parse these files with
'btf__parse' which tries both raw format and ELF format.

This might be useful in some scenarios where users put their custom BTF
into known locations and don't want to specify btf_custom_path option.

Signed-off-by: Tao Chen <chentao.kernel@linux.alibaba.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/3f59fb5a345d2e4f10e16fe9e35fbc4c03ecaa3e.1662999860.git.chentao.kernel@linux.alibaba.com
2022-09-27 15:23:45 -07:00
Yonghong Song
aa25f218b4 libbpf: Improve BPF_PROG2 macro code quality and description
Commit 34586d29f8df ("libbpf: Add new BPF_PROG2 macro") added BPF_PROG2
macro for trampoline based programs with struct arguments. Andrii
made a few suggestions to improve code quality and description.
This patch implemented these suggestions including better internal
macro name, consistent usage pattern for __builtin_choose_expr(),
simpler macro definition for always-inline func arguments and
better macro description.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20220910025214.1536510-1-yhs@fb.com
2022-09-27 15:23:45 -07:00
David Vernet
9e9bf46c92 bpf: Add libbpf logic for user-space ring buffer
Now that all of the logic is in place in the kernel to support user-space
produced ring buffers, we can add the user-space logic to libbpf. This
patch therefore adds the following public symbols to libbpf:

struct user_ring_buffer *
user_ring_buffer__new(int map_fd,
		      const struct user_ring_buffer_opts *opts);
void *user_ring_buffer__reserve(struct user_ring_buffer *rb, __u32 size);
void *user_ring_buffer__reserve_blocking(struct user_ring_buffer *rb,
                                         __u32 size, int timeout_ms);
void user_ring_buffer__submit(struct user_ring_buffer *rb, void *sample);
void user_ring_buffer__discard(struct user_ring_buffer *rb,
void user_ring_buffer__free(struct user_ring_buffer *rb);

A user-space producer must first create a struct user_ring_buffer * object
with user_ring_buffer__new(), and can then reserve samples in the
ring buffer using one of the following two symbols:

void *user_ring_buffer__reserve(struct user_ring_buffer *rb, __u32 size);
void *user_ring_buffer__reserve_blocking(struct user_ring_buffer *rb,
                                         __u32 size, int timeout_ms);

With user_ring_buffer__reserve(), a pointer to a 'size' region of the ring
buffer will be returned if sufficient space is available in the buffer.
user_ring_buffer__reserve_blocking() provides similar semantics, but will
block for up to 'timeout_ms' in epoll_wait if there is insufficient space
in the buffer. This function has the guarantee from the kernel that it will
receive at least one event-notification per invocation to
bpf_ringbuf_drain(), provided that at least one sample is drained, and the
BPF program did not pass the BPF_RB_NO_WAKEUP flag to bpf_ringbuf_drain().

Once a sample is reserved, it must either be committed to the ring buffer
with user_ring_buffer__submit(), or discarded with
user_ring_buffer__discard().

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220920000100.477320-4-void@manifault.com
2022-09-27 15:23:45 -07:00
David Vernet
28903eb40e bpf: Add bpf_user_ringbuf_drain() helper
In a prior change, we added a new BPF_MAP_TYPE_USER_RINGBUF map type which
will allow user-space applications to publish messages to a ring buffer
that is consumed by a BPF program in kernel-space. In order for this
map-type to be useful, it will require a BPF helper function that BPF
programs can invoke to drain samples from the ring buffer, and invoke
callbacks on those samples. This change adds that capability via a new BPF
helper function:

bpf_user_ringbuf_drain(struct bpf_map *map, void *callback_fn, void *ctx,
                       u64 flags)

BPF programs may invoke this function to run callback_fn() on a series of
samples in the ring buffer. callback_fn() has the following signature:

long callback_fn(struct bpf_dynptr *dynptr, void *context);

Samples are provided to the callback in the form of struct bpf_dynptr *'s,
which the program can read using BPF helper functions for querying
struct bpf_dynptr's.

In order to support bpf_ringbuf_drain(), a new PTR_TO_DYNPTR register
type is added to the verifier to reflect a dynptr that was allocated by
a helper function and passed to a BPF program. Unlike PTR_TO_STACK
dynptrs which are allocated on the stack by a BPF program, PTR_TO_DYNPTR
dynptrs need not use reference tracking, as the BPF helper is trusted to
properly free the dynptr before returning. The verifier currently only
supports PTR_TO_DYNPTR registers that are also DYNPTR_TYPE_LOCAL.

Note that while the corresponding user-space libbpf logic will be added
in a subsequent patch, this patch does contain an implementation of the
.map_poll() callback for BPF_MAP_TYPE_USER_RINGBUF maps. This
.map_poll() callback guarantees that an epoll-waiting user-space
producer will receive at least one event notification whenever at least
one sample is drained in an invocation of bpf_user_ringbuf_drain(),
provided that the function is not invoked with the BPF_RB_NO_WAKEUP
flag. If the BPF_RB_FORCE_WAKEUP flag is provided, a wakeup
notification is sent even if no sample was drained.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220920000100.477320-3-void@manifault.com
2022-09-27 15:23:45 -07:00
David Vernet
8138aa78bd bpf: Define new BPF_MAP_TYPE_USER_RINGBUF map type
We want to support a ringbuf map type where samples are published from
user-space, to be consumed by BPF programs. BPF currently supports a
kernel -> user-space circular ring buffer via the BPF_MAP_TYPE_RINGBUF
map type.  We'll need to define a new map type for user-space -> kernel,
as none of the helpers exported for BPF_MAP_TYPE_RINGBUF will apply
to a user-space producer ring buffer, and we'll want to add one or
more helper functions that would not apply for a kernel-producer
ring buffer.

This patch therefore adds a new BPF_MAP_TYPE_USER_RINGBUF map type
definition. The map type is useless in its current form, as there is no
way to access or use it for anything until we one or more BPF helpers. A
follow-on patch will therefore add a new helper function that allows BPF
programs to run callbacks on samples that are published to the ring
buffer.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220920000100.477320-2-void@manifault.com
2022-09-27 15:23:45 -07:00
Xin Liu
8ac9773f52 libbpf: Fix NULL pointer exception in API btf_dump__dump_type_data
We found that function btf_dump__dump_type_data can be called by the
user as an API, but in this function, the `opts` parameter may be used
as a null pointer.This causes `opts->indent_str` to trigger a NULL
pointer exception.

Fixes: 2ce8450ef5a3 ("libbpf: add bpf_object__open_{file, mem} w/ extensible opts")
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Weibin Kong <kongweibin2@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220917084809.30770-1-liuxin350@huawei.com
2022-09-27 15:23:45 -07:00
Xin Liu
b63791cbde libbpf: Clean up legacy bpf maps declaration in bpf_helpers
Legacy BPF map declarations are no longer supported in libbpf v1.0 [0].
Only BTF-defined maps are supported starting from v1.0, so it is time to
remove the definition of bpf_map_def in bpf_helpers.h.

  [0] https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0

Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20220913073643.19960-1-liuxin350@huawei.com
2022-09-27 15:23:45 -07:00
Andrii Nakryiko
0ff6d28aec libbpf: Fix crash if SEC("freplace") programs don't have attach_prog_fd set
Fix SIGSEGV caused by libbpf trying to find attach type in vmlinux BTF
for freplace programs. It's wrong to search in vmlinux BTF and libbpf
doesn't even mark vmlinux BTF as required for freplace programs. So
trying to search anything in obj->vmlinux_btf might cause NULL
dereference if nothing else in BPF object requires vmlinux BTF.

Instead, error out if freplace (EXT) program doesn't specify
attach_prog_fd during at the load time.

Fixes: 91abb4a6d79d ("libbpf: Support attachment of BPF tracing programs to kernel modules")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220909193053.577111-3-andrii@kernel.org
2022-09-27 15:23:45 -07:00
Daniel Borkmann
861364fa45 libbpf: Remove gcc support for bpf_tail_call_static for now
This reverts commit 14e5ce79943a ("libbpf: Add GCC support for
bpf_tail_call_static"). Reason is that gcc invented their own BPF asm
which is not conform with LLVM one, and going forward this would be
more painful to maintain here and in other areas of the library. Thus
remove it; ask to gcc folks is to align with LLVM one to use exact
same syntax.

Fixes: 14e5ce79943a ("libbpf: Add GCC support for bpf_tail_call_static")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: James Hilliard <james.hilliard1@gmail.com>
Cc: Jose E. Marchesi <jose.marchesi@oracle.com>
2022-09-27 15:23:45 -07:00
Yonghong Song
21ec5ca723 libbpf: Add new BPF_PROG2 macro
To support struct arguments in trampoline based programs,
existing BPF_PROG doesn't work any more since
the type size is needed to find whether a parameter
takes one or two registers. So this patch added a new
BPF_PROG2 macro to support such trampoline programs.

The idea is suggested by Andrii. For example, if the
to-be-traced function has signature like
  typedef struct {
       void *x;
       int t;
  } sockptr;
  int blah(sockptr x, char y);

In the new BPF_PROG2 macro, the argument can be
represented as
  __bpf_prog_call(
     ({ union {
          struct { __u64 x, y; } ___z;
          sockptr x;
        } ___tmp = { .___z = { ctx[0], ctx[1] }};
        ___tmp.x;
     }),
     ({ union {
          struct { __u8 x; } ___z;
          char y;
        } ___tmp = { .___z = { ctx[2] }};
        ___tmp.y;
     }));
In the above, the values stored on the stack are properly
assigned to the actual argument type value by using 'union'
magic. Note that the macro also works even if no arguments
are with struct types.

Note that new BPF_PROG2 works for both llvm16 and pre-llvm16
compilers where llvm16 supports bpf target passing value
with struct up to 16 byte size and pre-llvm16 will pass
by reference by storing values on the stack. With static functions
with struct argument as always inline, the compiler is able
to optimize and remove additional stack saving of struct values.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220831152707.2079473-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Yonghong Song
255690da57 bpf: Update descriptions for helpers bpf_get_func_arg[_cnt]()
Now instead of the number of arguments, the number of registers
holding argument values are stored in trampoline. Update
the description of bpf_get_func_arg[_cnt]() helpers. Previous
programs without struct arguments should continue to work
as usual.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220831152657.2078805-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Shmulik Ladkani
b1753eaf3b bpf: Support getting tunnel flags
Existing 'bpf_skb_get_tunnel_key' extracts various tunnel parameters
(id, ttl, tos, local and remote) but does not expose ip_tunnel_info's
tun_flags to the BPF program.

It makes sense to expose tun_flags to the BPF program.

Assume for example multiple GRE tunnels maintained on a single GRE
interface in collect_md mode. The program expects origins to initiate
over GRE, however different origins use different GRE characteristics
(e.g. some prefer to use GRE checksum, some do not; some pass a GRE key,
some do not, etc..).

A BPF program getting tun_flags can therefore remember the relevant
flags (e.g. TUNNEL_CSUM, TUNNEL_SEQ...) for each initiating remote. In
the reply path, the program can use 'bpf_skb_set_tunnel_key' in order
to correctly reply to the remote, using similar characteristics, based
on the stored tunnel flags.

Introduce BPF_F_TUNINFO_FLAGS flag for bpf_skb_get_tunnel_key. If
specified, 'bpf_tunnel_key->tunnel_flags' is set with the tun_flags.

Decided to use the existing unused 'tunnel_ext' as the storage for the
'tunnel_flags' in order to avoid changing bpf_tunnel_key's layout.

Also, the following has been considered during the design:

  1. Convert the "interesting" internal TUNNEL_xxx flags back to BPF_F_yyy
     and place into the new 'tunnel_flags' field. This has 2 drawbacks:

     - The BPF_F_yyy flags are from *set_tunnel_key* enumeration space,
       e.g. BPF_F_ZERO_CSUM_TX. It is awkward that it is "returned" into
       tunnel_flags from a *get_tunnel_key* call.
     - Not all "interesting" TUNNEL_xxx flags can be mapped to existing
       BPF_F_yyy flags, and it doesn't make sense to create new BPF_F_yyy
       flags just for purposes of the returned tunnel_flags.

  2. Place key.tun_flags into 'tunnel_flags' but mask them, keeping only
     "interesting" flags. That's ok, but the drawback is that what's
     "interesting" for my usecase might be limiting for other usecases.

Therefore I decided to expose what's in key.tun_flags *as is*, which seems
most flexible. The BPF user can just choose to ignore bits he's not
interested in. The TUNNEL_xxx are also UAPI, so no harm exposing them
back in the get_tunnel_key call.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220831144010.174110-1-shmulik.ladkani@gmail.com
2022-09-27 15:23:45 -07:00
James Hilliard
eeb2bc4061 libbpf: Add GCC support for bpf_tail_call_static
The bpf_tail_call_static function is currently not defined unless
using clang >= 8.

To support bpf_tail_call_static on GCC we can check if __clang__ is
not defined to enable bpf_tail_call_static.

We need to use GCC assembly syntax when the compiler does not define
__clang__ as LLVM inline assembly is not fully compatible with GCC.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220829210546.755377-1-james.hilliard1@gmail.com
2022-09-27 15:23:45 -07:00
Quentin Monnet
a11587cc01 bpf: Fix a few typos in BPF helpers documentation
Address a few typos in the documentation for the BPF helper functions.
They were reported by Jakub [0], who ran spell checkers on the generated
man page [1].

[0] https://lore.kernel.org/linux-man/d22dcd47-023c-8f52-d369-7b5308e6c842@gmail.com/T/#mb02e7d4b7fb61d98fa914c77b581184e9a9537af
[1] https://lore.kernel.org/linux-man/eb6a1e41-c48e-ac45-5154-ac57a2c76108@gmail.com/T/#m4a8d1b003616928013ffcd1450437309ab652f9f

v3: Do not copy unrelated (and breaking) elements to tools/ header
v2: Turn a ',' into a ';'

Reported-by: Jakub Wilk <jwilk@jwilk.net>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220825220806.107143-1-quentin@isovalent.com
2022-09-27 15:23:45 -07:00
Benjamin Tissoires
7fb6138fae libbpf: add map_get_fd_by_id and map_delete_elem in light skeleton
This allows to have a better control over maps from the kernel when
preloading eBPF programs.

Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20220824134055.1328882-8-benjamin.tissoires@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Hao Luo
c918b3e724 bpf: Add CGROUP prefix to cgroup_iter_order
bpf_cgroup_iter_order is globally visible but the entries do not have
CGROUP prefix. As requested by Andrii, put a CGROUP in the names
in bpf_cgroup_iter_order.

This patch fixes two previous commits: one introduced the API and
the other uses the API in bpf selftest (that is, the selftest
cgroup_hierarchical_stats).

I tested this patch via the following command:

  test_progs -t cgroup,iter,btf_dump

Fixes: d4ccaf58a847 ("bpf: Introduce cgroup iter")
Fixes: 88886309d2e8 ("selftests/bpf: add a selftest for cgroup hierarchical stats collection")
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/r/20220825223936.1865810-1-haoluo@google.com
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
2022-09-27 15:23:45 -07:00
Hao Luo
981001bf46 bpf: Introduce cgroup iter
Cgroup_iter is a type of bpf_iter. It walks over cgroups in four modes:

 - walking a cgroup's descendants in pre-order.
 - walking a cgroup's descendants in post-order.
 - walking a cgroup's ancestors.
 - process only the given cgroup.

When attaching cgroup_iter, one can set a cgroup to the iter_link
created from attaching. This cgroup is passed as a file descriptor
or cgroup id and serves as the starting point of the walk. If no
cgroup is specified, the starting point will be the root cgroup v2.

For walking descendants, one can specify the order: either pre-order or
post-order. For walking ancestors, the walk starts at the specified
cgroup and ends at the root.

One can also terminate the walk early by returning 1 from the iter
program.

Note that because walking cgroup hierarchy holds cgroup_mutex, the iter
program is called with cgroup_mutex held.

Currently only one session is supported, which means, depending on the
volume of data bpf program intends to send to user space, the number
of cgroups that can be walked is limited. For example, given the current
buffer size is 8 * PAGE_SIZE, if the program sends 64B data for each
cgroup, assuming PAGE_SIZE is 4kb, the total number of cgroups that can
be walked is 512. This is a limitation of cgroup_iter. If the output
data is larger than the kernel buffer size, after all data in the
kernel buffer is consumed by user space, the subsequent read() syscall
will signal EOPNOTSUPP. In order to work around, the user may have to
update their program to reduce the volume of data sent to output. For
example, skip some uninteresting cgroups. In future, we may extend
bpf_iter flags to allow customizing buffer size.

Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/r/20220824233117.1312810-2-haoluo@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Stanislav Fomichev
ee7d295f83 bpf: update bpf_{g,s}et_retval documentation
* replace 'syscall' with 'upper layers', still mention that it's being
  exported via syscall errno
* describe what happens in set_retval(-EPERM) + return 1
* describe what happens with bind's 'return 3'

Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220823222555.523590-5-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-27 15:23:45 -07:00
Shmulik Ladkani
94d69cc07f bpf, flow_dissector: Introduce BPF_FLOW_DISSECTOR_CONTINUE retcode for bpf progs
Currently, attaching BPF_PROG_TYPE_FLOW_DISSECTOR programs completely
replaces the flow-dissector logic with custom dissection logic. This
forces implementors to write programs that handle dissection for any
flows expected in the namespace.

It makes sense for flow-dissector BPF programs to just augment the
dissector with custom logic (e.g. dissecting certain flows or custom
protocols), while enjoying the broad capabilities of the standard
dissector for any other traffic.

Introduce BPF_FLOW_DISSECTOR_CONTINUE retcode. Flow-dissector BPF
programs may return this to indicate no dissection was made, and
fallback to the standard dissector is requested.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220821113519.116765-3-shmulik.ladkani@gmail.com
2022-09-27 15:23:45 -07:00
Mikhail Tuzikov
12a41a80c5 Adding network diag utils into actions-runner-libbpf container 2022-09-27 11:06:30 -07:00
Daniel Müller
10a32130e7 Clean up local allow/deny lists
Now that we are including the upstream allow/deny lists we can remove
any duplicates from our local lists. While at it, we also add some usdt
tests to the denylist, which are currently failing. This is the same
step we took in the vmtest repository [0].

[0] https://github.com/kernel-patches/vmtest/pull/133

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-09-06 15:01:05 -07:00
Daniel Müller
fad270918d Use deny/allow lists from upstream
So far we have relied on allow/deny lists maintained in this repository
to decide which tests to explicitly include/exclude from running in CI.
With recent changes [0] this information is now available in upstream
Linux.
As such, this change switches us over to using the upstream allow/deny
lists in addition to the local ones. We unconditionally honor the
upstream lists for all kernel versions.

[0] https://lore.kernel.org/bpf/165893461358.29339.11641967418379627671.git-patchwork-notify@kernel.org/T/#m2a97b0ea9ef0ddee7a53bbf7919e3f324b233937

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-09-06 15:01:05 -07:00
Daniel Müller
c091b07808 Fix comment: WHITELIST -> ALLOWLIST
Commit 693de729d0 ("Rename blacklists and whitelists") renamed the
black and white lists but missed the adjustment of a comment,
referencing a file name. Update it accordingly.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-09-06 14:07:51 -07:00
Daniel Müller
efd33720cd Set KERNEL and REPO_ROOT environment variable for run-qemu action
With an upcoming change we would like to invoke bpftool checks from the
run-qemu action (https://github.com/libbpf/ci/pull/37). This action
requires two environment variables, KERNEL and REPO_ROOT, set in order
to function.
Make sure to set them now. Long term we should probably make them
explicit input arguments instead of implicit global state, but there are
many more such instances that we need to clean up.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-09-01 11:00:13 -07:00
Daniel Müller
9aedff8d03 Provide kernel-root argument to run-qemu action
With https://github.com/libbpf/ci/pull/36 merged the run-qemu action now
accepts an additional argument, `kernel-root`.
Provide it to the action with the value appropriate for this repository.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-09-01 10:36:35 -07:00
Daniel Müller
51e63f7229 Explicitly provide kernel-root argument to prepare-rootfs action
Let's make the "kernel-root" explicit when using the prepare-rootfs
action, instead of relying on the default, .kernel.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-08-29 11:14:39 -07:00
chantra
c53af98d1a [s390x][runner] update action runner to 2.296.0 (latest) 2022-08-27 17:14:28 -07:00
chantra
2c44349e09 [s390x][runners] Use consistent runner name across restarts
Currently, the runner name is taken from the docker container's
hostname.
This changes across restarts, causing the runner name to change across
restarts too.

This uses the host name to keep a consistent name.
2022-08-27 17:14:28 -07:00
Daniel Müller
58361243ec Fix sourcing of helpers.sh in coverity workflow
The path to the helpers.sh script to source was put one level too deep
by cfbd763ef8 ("Use foldable helpers where applicable") and the
GITHUB_ACTION_PATH variable is not actually defined in a workflow.

Fix up both issues.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-08-26 11:30:12 -07:00
Andrii Nakryiko
c32e1cf948 README: add dark background logo image
Add auto-selectable libbpf logo for light and dark themes.

Suggested-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-08-24 22:09:09 -07:00
Andrii Nakryiko
c4f44c7c11 assets: add libbpf logo images
Add three layouts of libbpf logos (sparse, compact, sideways) with three
color variants (light bg, dark bg, monochrome).

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-08-24 21:51:42 -07:00
Daniel Müller
a7a525d47a Rename test_progs_noalu function to test_progs_no_alu32
As a follow up to 66b788c1a4 ("Factor out test_progs_noalu function")
and taking into account feedback [0], this change renames the
test_progs_noalu function to test_progs_no_alu32, to stay closer to the
name of the binary being invoked.

[0] https://github.com/kernel-patches/vmtest/pull/124#discussion_r953175641

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-08-24 08:08:21 -07:00
Daniel Müller
cfbd763ef8 Use foldable helpers where applicable
As discussed at some earlier point in time, some of the actions/workflow
logic does not use our foldable helpers despite being able to. Switch
them over.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-08-23 12:04:38 -07:00
thiagoftsm
862b60f205 Merge branch 'libbpf:master' into master v1.0.0_netdata 2022-08-22 19:29:03 +00:00
Andrii Nakryiko
a0325403af readme: add logo and clarify initial section
Add libbpf logo to the header and restructure and rewrite a bit
intro part about libbpf, it's bpf-next origins, etc.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-08-22 12:10:03 -07:00
Andrii Nakryiko
7436656dbf README: add link to readthedocs doc site
Add link to https://libbpf.readthedocs.io/en/latest/api.html for API documentation.
2022-08-19 10:37:43 -07:00
Daniel Müller
7984737fbf Support running of individual tests
This change adjusts the run_selftests.sh script to accept an optional
list of arguments specifying the tests to run. We will make use of it
once we run selftests in parallel.

Signed-off-by: Daniel Müller <deso@posteo.net>
2022-08-18 15:31:52 -07:00
Andrii Nakryiko
a0d1e22c77 ci: blacklist lru_bug selftest on s390x
Make sure we don't fail on lru_bug selftests as it relies of BPF
trampoline, not supported by s390x.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-08-18 15:29:04 -07:00
Andrii Nakryiko
e58c615210 ci: update vmlinux.h to latest config
Some selftests require conn->mark, regenerate vmlinux.h.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2022-08-18 15:29:04 -07:00