linux.git/tools/bpf/bpftool/Documentation, branch v5.5

tools: bpftool: add "bpftool map freeze" subcommand

2019-08-21T19:17:27+00:00

Add a new subcommand to freeze maps from user space.

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Daniel Borkmann

tools: bpftool: implement "bpftool btf show|list"

2019-08-20T16:51:06+00:00

Add a "btf list" (alias: "btf show") subcommand to bpftool in order to
dump all BTF objects loaded on a system.

When running the command, hash tables are built in bpftool to retrieve
all the associations between BTF objects and BPF maps and programs. This
allows for printing all such associations when listing the BTF objects.

The command is added at the top of the subcommands for "bpftool btf", so
that typing only "bpftool btf" also comes down to listing the programs.
We could not have this with the previous command ("dump"), which
required a BTF object id, so it should not break any previous behaviour.
This also makes the "btf" command behaviour consistent with "prog" or
"map".

Bash completion is updated to use "bpftool btf" instead of "bpftool
prog" to list the BTF ids, as it looks more consistent.

Example output (plain):

    # bpftool btf show
    9: size 2989B  prog_ids 21  map_ids 15
    17: size 2847B  prog_ids 36  map_ids 30,29,28
    26: size 2847B

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Signed-off-by: Alexei Starovoitov

tools: bpftool: add documentation for net attach/detach

2019-08-16T00:00:33+00:00

Since, new sub-command 'net attach/detach' has been added for
attaching XDP program on interface,
this commit documents usage and sample output of `net attach/detach`.

Signed-off-by: Daniel T. Lee 
Signed-off-by: Alexei Starovoitov

tools: bpftool: add support for reporting the effective cgroup progs

2019-07-31T04:15:02+00:00

Takshak said in the original submission:

With different bpf attach_flags available to attach bpf programs specially
with BPF_F_ALLOW_OVERRIDE and BPF_F_ALLOW_MULTI, the list of effective
bpf-programs available to any sub-cgroups really needs to be available for
easy debugging.

Using BPF_F_QUERY_EFFECTIVE flag, one can get the list of not only attached
bpf-programs to a cgroup but also the inherited ones from parent cgroup.

So a new option is introduced to use BPF_F_QUERY_EFFECTIVE query flag here
to list all the effective bpf-programs available for execution at a specified
cgroup.

Reused modified test program test_cgroup_attach from tools/testing/selftests/bpf:
  # ./test_cgroup_attach

With old bpftool:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/
  ID       AttachType      AttachFlags     Name
  271      egress          multi           pkt_cntr_1
  272      egress          multi           pkt_cntr_2

Attached new program pkt_cntr_4 in cg2 gives following:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2
  ID       AttachType      AttachFlags     Name
  273      egress          override        pkt_cntr_4

And with new "effective" option it shows all effective programs for cg2:

 # bpftool cgroup show /sys/fs/cgroup/cgroup-test-work-dir/cg1/cg2 effective
  ID       AttachType      AttachFlags     Name
  273      egress          override        pkt_cntr_4
  271      egress          override        pkt_cntr_1
  272      egress          override        pkt_cntr_2

Compared to original submission use a local flag instead of global
option.

We need to clear query_flags on every command, in case batch mode
wants to use varying settings.

v2: (Takshak)
 - forbid duplicated flags;
 - fix cgroup path freeing.

Signed-off-by: Takshak Chahande 
Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Reviewed-by: Takshak Chahande 
Signed-off-by: Alexei Starovoitov

tools: Add definitions for devmap_hash map type

2019-07-29T20:50:48+00:00

This adds selftest and bpftool updates for the devmap_hash map type.

Signed-off-by: Toke Høiland-Jørgensen 
Acked-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

tools: bpftool: add "prog run" subcommand to test-run programs

2019-07-05T21:48:07+00:00

Add a new "bpftool prog run" subcommand to run a loaded program on input
data (and possibly with input context) passed by the user.

Print output data (and output context if relevant) into a file or into
the console. Print return value and duration for the test run into the
console.

A "repeat" argument can be passed to run the program several times in a
row.

The command does not perform any kind of verification based on program
type (Is this program type allowed to use an input context?) or on data
consistency (Can I work with empty input data?), this is left to the
kernel.

Example invocation:

    # perl -e 'print "\x0" x 14' | ./bpftool prog run \
            pinned /sys/fs/bpf/sample_ret0 \
            data_in - data_out - repeat 5
    0000000 0000 0000 0000 0000 0000 0000 0000      | ........ ......
    Return value: 0, duration (average): 260ns

When one of data_in or ctx_in is "-", bpftool reads from standard input,
in binary format. Other formats (JSON, hexdump) might be supported (via
an optional command line keyword like "data_fmt_in") in the future if
relevant, but this would require doing more parsing in bpftool.

v2:
- Fix argument names for function check_single_stdin(). (Yonghong)

Signed-off-by: Quentin Monnet 
Reviewed-by: Jakub Kicinski 
Acked-by: Yonghong Song 
Signed-off-by: Daniel Borkmann

bpftool: support cgroup sockopt

2019-06-27T22:25:17+00:00

Support sockopt prog type and cgroup hooks in the bpftool.

Cc: Andrii Nakryiko 
Cc: Martin Lau 
Acked-by: Jakub Kicinski 
Signed-off-by: Stanislav Fomichev 
Signed-off-by: Alexei Starovoitov

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2019-06-18T03:20:36+00:00

Honestly all the conflicts were simple overlapping changes,
nothing really interesting to report.

Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2019-06-07T21:46:47+00:00

Daniel Borkmann says:

====================
pull-request: bpf 2019-06-07

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

The main changes are:

1) Fix several bugs in riscv64 JIT code emission which forgot to clear high
   32-bits for alu32 ops, from Björn and Luke with selftests covering all
   relevant BPF alu ops from Björn and Jiong.

2) Two fixes for UDP BPF reuseport that avoid calling the program in case of
   __udp6_lib_err and UDP GRO which broke reuseport_select_sock() assumption
   that skb->data is pointing to transport header, from Martin.

3) Two fixes for BPF sockmap: a use-after-free from sleep in psock's backlog
   workqueue, and a missing restore of sk_write_space when psock gets dropped,
   from Jakub and John.

4) Fix unconnected UDP sendmsg hook API which is insufficient as-is since it
   breaks standard applications like DNS if reverse NAT is not performed upon
   receive, from Daniel.

5) Fix an out-of-bounds read in __bpf_skc_lookup which in case of AF_INET6
   fails to verify that the length of the tuple is long enough, from Lorenz.

6) Fix libbpf's libbpf__probe_raw_btf to return an fd instead of 0/1 (for
   {un,}successful probe) as that is expected to be propagated as an fd to
   load_sk_storage_btf() and thus closing the wrong descriptor otherwise,
   from Michal.

7) Fix bpftool's JSON output for the case when a lookup fails, from Krzesimir.

8) Minor misc fixes in docs, samples and selftests, from various others.
====================

Signed-off-by: David S. Miller

bpf, bpftool: enable recvmsg attach types

2019-06-06T23:53:12+00:00

Trivial patch to bpftool in order to complete enabling attaching programs
to BPF_CGROUP_UDP{4,6}_RECVMSG.

Signed-off-by: Daniel Borkmann 
Acked-by: Andrey Ignatov 
Acked-by: Martin KaFai Lau 
Signed-off-by: Alexei Starovoitov