From patchwork Wed Feb 28 09:02:41 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 13575076 X-Patchwork-Delegate: bpf@iogearbox.net 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 88E4A31A94 for ; Wed, 28 Feb 2024 09:03:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709111003; cv=none; b=XPyIDft147gRMTHzKNSft3r++o6P2vHvenRTxQA5t9ukxCnYY+VczM/CoBzjJVjJZ4Lsq04uSvSSf7usoC44x8m2sWY7o/lhUYDRm+yU7GebmSxhDg2VHXT2yM9TxjPuaSOGjmzfv1zqwzGF0mSnrlT2lEwmL/VRP2MLzlPrT0M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709111003; c=relaxed/simple; bh=ETUdGq+ubKGgZlGTk6No23JdOZXS4gyPRBS//b/nowM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eq0wnUo3pQnRzvihE7xMSXCKfVZREwyR2D5zH1FHWV0Ex7w5Fq2TnPrkeo8r4z8MI81Q8oB4mwr/IU8B6l37OFQ9ZyC9xKtgKCTcPHJSbOv+kazJfqrolMs1NMYDkZ4yPbOZ4Lv9Petq591J6F3qS7+ZCKNJTwvMSht0T9nK7XI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rP/9QD9b; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rP/9QD9b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79B90C433C7; Wed, 28 Feb 2024 09:03:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709111003; bh=ETUdGq+ubKGgZlGTk6No23JdOZXS4gyPRBS//b/nowM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rP/9QD9bLw5uKP0YbH2iFnHYCQfxU5JiXH65FAJDvAAwM72OhQf37vvm9Cf1j3Q/Q V4dsav7sfYorj9KZYDFkNKIw67MXuQPJwGs3On/s+E6F/Fz07eCvvmuiCsRawhJTu3 76UBlzBymftN2rjxwui2YI14ccizpaCllgYvjHV5R/X29AIj3ShJA+lh49bnQxEMZa LQM/cKDWIztIRov0h8xLVDKOuQE7JZnaAz9LPN7P5F21q9XcWlJcatMJpiQXXmCToq bJkDyBJ9HPMiwNh4KMLVi51nac2FSCZqRhm5GpBby2XdD1Dk3zAEdVjaStrjuMZBHN gHupndNdHGwPA== 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 , "Masami Hiramatsu (Google)" , Viktor Malik Subject: [PATCH RFCv2 bpf-next 3/4] libbpf: Add support for kprobe multi wrapper attach Date: Wed, 28 Feb 2024 10:02:41 +0100 Message-ID: <20240228090242.4040210-4-jolsa@kernel.org> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20240228090242.4040210-1-jolsa@kernel.org> References: <20240228090242.4040210-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net X-Patchwork-State: RFC Adding support for specify wrapper mode in bpf_kprobe_multi_opts struct object and new bpf program loader section: SEC("kprobe.wrapper/bpf_fentry_test*") to load program as kprobe multi wrapper. Signed-off-by: Jiri Olsa --- tools/lib/bpf/libbpf.c | 38 +++++++++++++++++++++++++++++++++++--- tools/lib/bpf/libbpf.h | 4 +++- 2 files changed, 38 insertions(+), 4 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 01f407591a92..5416d784c857 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8944,6 +8944,7 @@ static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_lin static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); +static int attach_kprobe_wrapper(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link); @@ -8960,6 +8961,7 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("uretprobe.s+", KPROBE, 0, SEC_SLEEPABLE, attach_uprobe), SEC_DEF("kprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), SEC_DEF("kretprobe.multi+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi), + SEC_DEF("kprobe.wrapper+", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_wrapper), SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), @@ -11034,7 +11036,7 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, int err, link_fd, prog_fd; const __u64 *cookies; const char **syms; - bool retprobe; + __u32 flags = 0; size_t cnt; if (!OPTS_VALID(opts, bpf_kprobe_multi_opts)) @@ -11065,13 +11067,16 @@ bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog, cnt = res.cnt; } - retprobe = OPTS_GET(opts, retprobe, false); + if (OPTS_GET(opts, retprobe, false)) + flags |= BPF_F_KPROBE_MULTI_RETURN; + if (OPTS_GET(opts, wrapper, false)) + flags |= BPF_F_KPROBE_MULTI_WRAPPER; lopts.kprobe_multi.syms = syms; lopts.kprobe_multi.addrs = addrs; lopts.kprobe_multi.cookies = cookies; lopts.kprobe_multi.cnt = cnt; - lopts.kprobe_multi.flags = retprobe ? BPF_F_KPROBE_MULTI_RETURN : 0; + lopts.kprobe_multi.flags = flags; link = calloc(1, sizeof(*link)); if (!link) { @@ -11187,6 +11192,33 @@ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, stru return libbpf_get_error(*link); } +static int attach_kprobe_wrapper(const struct bpf_program *prog, long cookie, struct bpf_link **link) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts, + .wrapper = true, + ); + const char *spec; + char *pattern; + int n; + + *link = NULL; + + /* no auto-attach for SEC("kprobe.wrapper") */ + if (strcmp(prog->sec_name, "kprobe.wrapper") == 0) + return 0; + + spec = prog->sec_name + sizeof("kprobe.wrapper/") - 1; + n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern); + if (n < 1) { + pr_warn("kprobe wrapper pattern is invalid: %s\n", pattern); + return -EINVAL; + } + + *link = bpf_program__attach_kprobe_multi_opts(prog, pattern, &opts); + free(pattern); + return libbpf_get_error(*link); +} + static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link) { char *probe_type = NULL, *binary_path = NULL, *func_name = NULL; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 5723cbbfcc41..72f4e3ad295f 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -539,10 +539,12 @@ struct bpf_kprobe_multi_opts { size_t cnt; /* create return kprobes */ bool retprobe; + /* create wrapper kprobes */ + bool wrapper; size_t :0; }; -#define bpf_kprobe_multi_opts__last_field retprobe +#define bpf_kprobe_multi_opts__last_field wrapper LIBBPF_API struct bpf_link * bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,