Commit Graph
6 Commits
Author SHA1 Message Date
Jiri Olsa 14f5433b2e libbpf: Export bpf_program__attach_kprobe_opts function
Export bpf_program__attach_kprobe_opts as a public API.

Rename bpf_program_attach_kprobe_opts to bpf_kprobe_opts and turn it into OPTS
struct.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20210721215810.889975-4-jolsa@kernel.org
2021-08-04 18:27:12 -07:00
Jiri Olsa d7a2de020b libbpf: Allow decimal offset for kprobes
Allow to specify decimal offset in SEC macro, like:
  SEC("kprobe/bpf_fentry_test7+5")

Add selftest for that.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20210721215810.889975-3-jolsa@kernel.org
2021-08-04 18:27:12 -07:00
Jiri Olsa bb92e7ab4d libbpf: Fix func leak in attach_kprobe
Add missing free() for func pointer in attach_kprobe function.

Fixes: a2488b5f483f ("libbpf: Allow specification of "kprobe/function+offset"")
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20210721215810.889975-2-jolsa@kernel.org
2021-08-04 18:27:12 -07:00
Jiri Olsa 330a158982 libbpf: Add bpf_program__attach_kprobe_opts function
Adding bpf_program__attach_kprobe_opts that does the same
as bpf_program__attach_kprobe, but takes opts argument.

Currently opts struct holds just retprobe bool, but we will
add new field in following patch.

The function is not exported, so there's no need to add
size to the struct bpf_program_attach_kprobe_opts for now.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-7-jolsa@kernel.org
2021-07-16 17:05:44 -07:00
Jiri Olsa a524ae0bbf bpf: Add bpf_get_func_ip helper for kprobe programs
Adding bpf_get_func_ip helper for BPF_PROG_TYPE_KPROBE programs,
so it's now possible to call bpf_get_func_ip from both kprobe and
kretprobe programs.

Taking the caller's address from 'struct kprobe::addr', which is
defined for both kprobe and kretprobe.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-5-jolsa@kernel.org
2021-07-16 17:05:44 -07:00
Jiri Olsa 97e2a9c9a1 bpf: Add bpf_get_func_ip helper for tracing programs
Adding bpf_get_func_ip helper for BPF_PROG_TYPE_TRACING programs,
specifically for all trampoline attach types.

The trampoline's caller IP address is stored in (ctx - 8) address.
so there's no reason to actually call the helper, but rather fixup
the call instruction and return [ctx - 8] value directly.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210714094400.396467-4-jolsa@kernel.org
2021-07-16 17:05:44 -07:00