From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DC11174E9 for ; Thu, 20 Jul 2023 11:38:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19D4DC433C8; Thu, 20 Jul 2023 11:38:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689853099; bh=82zW2HPRZutof+gZ/7V9zTD/TQLQ+oA3Yw9258jySFo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SDJyG8CxxKfzeC2rgGbzK+QZv8rDBQhXF2IivmMHG5oSPBRtwkHc/l5CG8WxroHK7 cCrxXfXvvU81d1uDbQA/GxF9iZR45mzCIQcRtzTO32Bxydk7zb1kDewQGyB9Wlilbe fHKU8BIPaMyTjSl1l80U/k0KjV/lLhm4hO6v8Nuk/soL1m3RtD4po/d4MpSLilcTxX EtatndKLFkcNpcLfEglv3S1S4p/pgigXSIi1wQglLq3xW35K0qqyBXUH85d9ecwkY7 fV9exHBrKuaQVgri+zxCMVfSA2nzV5wX4/kdxQolbj/G2SZCt2VfFl3jnBpZVIu+++ yNnr2Yecazx1g== From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: bpf@vger.kernel.org, Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo Subject: [PATCHv4 bpf-next 14/28] libbpf: Add bpf_program__attach_uprobe_multi function Date: Thu, 20 Jul 2023 13:35:36 +0200 Message-ID: <20230720113550.369257-15-jolsa@kernel.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230720113550.369257-1-jolsa@kernel.org> References: <20230720113550.369257-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Adding bpf_program__attach_uprobe_multi function that allows to attach multiple uprobes with uprobe_multi link. The user can specify uprobes with direct arguments: binary_path/func_pattern/pid or with struct bpf_uprobe_multi_opts opts argument fields: const char **syms; const unsigned long *offsets; const unsigned long *ref_ctr_offsets; const __u64 *cookies; User can specify 2 mutually exclusive set of inputs: 1) use only path/func_pattern/pid arguments 2) use path/pid with allowed combinations of: syms/offsets/ref_ctr_offsets/cookies/cnt - syms and offsets are mutually exclusive - ref_ctr_offsets and cookies are optional Any other usage results in error. Signed-off-by: Jiri Olsa --- tools/lib/bpf/libbpf.c | 114 +++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 51 ++++++++++++++++++ tools/lib/bpf/libbpf.map | 1 + 3 files changed, 166 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index b690a729d2c1..7a10a8b57dbc 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -11121,6 +11121,120 @@ static int resolve_full_path(const char *file, char *result, size_t result_sz) return -ENOENT; } +struct bpf_link * +bpf_program__attach_uprobe_multi(const struct bpf_program *prog, + pid_t pid, + const char *path, + const char *func_pattern, + const struct bpf_uprobe_multi_opts *opts) +{ + const unsigned long *ref_ctr_offsets = NULL, *offsets = NULL; + LIBBPF_OPTS(bpf_link_create_opts, lopts); + unsigned long *resolved_offsets = NULL; + int err = 0, link_fd, prog_fd; + struct bpf_link *link = NULL; + char errmsg[STRERR_BUFSIZE]; + char full_path[PATH_MAX]; + const __u64 *cookies; + const char **syms; + size_t cnt; + + if (!OPTS_VALID(opts, bpf_uprobe_multi_opts)) + return libbpf_err_ptr(-EINVAL); + + syms = OPTS_GET(opts, syms, NULL); + offsets = OPTS_GET(opts, offsets, NULL); + ref_ctr_offsets = OPTS_GET(opts, ref_ctr_offsets, NULL); + cookies = OPTS_GET(opts, cookies, NULL); + cnt = OPTS_GET(opts, cnt, 0); + + /* + * User can specify 2 mutually exclusive set of inputs: + * + * 1) use only path/func_pattern/pid arguments + * + * 2) use path/pid with allowed combinations of: + * syms/offsets/ref_ctr_offsets/cookies/cnt + * + * - syms and offsets are mutually exclusive + * - ref_ctr_offsets and cookies are optional + * + * Any other usage results in error. + */ + + if (!path) + return libbpf_err_ptr(-EINVAL); + if (!func_pattern && cnt == 0) + return libbpf_err_ptr(-EINVAL); + + if (func_pattern) { + if (syms || offsets || ref_ctr_offsets || cookies || cnt) + return libbpf_err_ptr(-EINVAL); + } else { + if (!!syms == !!offsets) + return libbpf_err_ptr(-EINVAL); + } + + if (func_pattern) { + if (!strchr(path, '/')) { + err = resolve_full_path(path, full_path, sizeof(full_path)); + if (err) { + pr_warn("prog '%s': failed to resolve full path for '%s': %d\n", + prog->name, path, err); + return libbpf_err_ptr(err); + } + path = full_path; + } + + err = elf_resolve_pattern_offsets(path, func_pattern, + &resolved_offsets, &cnt); + if (err < 0) + return libbpf_err_ptr(err); + offsets = resolved_offsets; + } else if (syms) { + err = elf_resolve_syms_offsets(path, cnt, syms, &resolved_offsets); + if (err < 0) + return libbpf_err_ptr(err); + offsets = resolved_offsets; + } + + lopts.uprobe_multi.path = path; + lopts.uprobe_multi.offsets = offsets; + lopts.uprobe_multi.ref_ctr_offsets = ref_ctr_offsets; + lopts.uprobe_multi.cookies = cookies; + lopts.uprobe_multi.cnt = cnt; + lopts.uprobe_multi.flags = OPTS_GET(opts, retprobe, false) ? BPF_F_UPROBE_MULTI_RETURN : 0; + + if (pid == 0) + pid = getpid(); + if (pid > 0) + lopts.uprobe_multi.pid = pid; + + link = calloc(1, sizeof(*link)); + if (!link) { + err = -ENOMEM; + goto error; + } + link->detach = &bpf_link__detach_fd; + + prog_fd = bpf_program__fd(prog); + link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &lopts); + if (link_fd < 0) { + err = -errno; + pr_warn("prog '%s': failed to attach multi-uprobe: %s\n", + prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + goto error; + } + link->fd = link_fd; + free(resolved_offsets); + return link; + +error: + free(resolved_offsets); + free(link); + return libbpf_err_ptr(err); +} + LIBBPF_API struct bpf_link * bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid, const char *binary_path, size_t func_offset, diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 10642ad69d76..2d8af7383cdb 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -529,6 +529,57 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, const char *pattern, const struct bpf_kprobe_multi_opts *opts); +struct bpf_uprobe_multi_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + /* array of function symbols to attach to */ + const char **syms; + /* array of function addresses to attach to */ + const unsigned long *offsets; + /* optional, array of associated ref counter offsets */ + const unsigned long *ref_ctr_offsets; + /* optional, array of associated BPF cookies */ + const __u64 *cookies; + /* number of elements in syms/addrs/cookies arrays */ + size_t cnt; + /* create return uprobes */ + bool retprobe; + size_t :0; +}; + +#define bpf_uprobe_multi_opts__last_field retprobe + +/** + * @brief **bpf_program__attach_uprobe_multi()** attaches a BPF program + * to multiple uprobes with uprobe_multi link. + * + * User can specify 2 mutually exclusive set of inputs: + * + * 1) use only path/func_pattern/pid arguments + * + * 2) use path/pid with allowed combinations of + * syms/offsets/ref_ctr_offsets/cookies/cnt + * + * - syms and offsets are mutually exclusive + * - ref_ctr_offsets and cookies are optional + * + * + * @param prog BPF program to attach + * @param pid Process ID to attach the uprobe to, 0 for self (own process), + * -1 for all processes + * @param binary_path Path to binary + * @param func_pattern Regular expression to specify functions to attach + * BPF program to + * @param opts Additional options (see **struct bpf_uprobe_multi_opts**) + * @return 0, on success; negative error code, otherwise + */ +LIBBPF_API struct bpf_link * +bpf_program__attach_uprobe_multi(const struct bpf_program *prog, + pid_t pid, + const char *binary_path, + const char *func_pattern, + const struct bpf_uprobe_multi_opts *opts); + struct bpf_ksyscall_opts { /* size of this struct, for forward/backward compatibility */ size_t sz; diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index d9ec4407befa..cb859846d189 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -396,4 +396,5 @@ LIBBPF_1.3.0 { global: bpf_obj_pin_opts; bpf_program__attach_netfilter; + bpf_program__attach_uprobe_multi; } LIBBPF_1.2.0; -- 2.41.0