From patchwork Sat Apr 16 04:29:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 12815678 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 159F7C433EF for ; Sat, 16 Apr 2022 04:30:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230070AbiDPEdJ (ORCPT ); Sat, 16 Apr 2022 00:33:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230024AbiDPEdI (ORCPT ); Sat, 16 Apr 2022 00:33:08 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 776A7F8952 for ; Fri, 15 Apr 2022 21:30:38 -0700 (PDT) Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 23FL4mIB032279 for ; Fri, 15 Apr 2022 21:30:37 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=kVClICmPhRu4+zdqxpx7VE2gMIM07yuZ+bMvzcBRTsI=; b=TwxWo5uiU+utTL3OHVdLUwzKk/2JtCrf16LtH8nPXWp8+3ydanZkvwXNaJ2efFpm9uVp ed+XMgcKIQvA2nI0kk+GAFWRzOL3y+ryI1XiBPmI+GHasYbdEu9MOMsFUn9oJ3bgaPd1 FFIPCR55vK3CpPyqwsjRkjXTnMh3a0M7YEE= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3fewgpq0m8-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Fri, 15 Apr 2022 21:30:37 -0700 Received: from twshared19572.14.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 15 Apr 2022 21:30:36 -0700 Received: by devbig931.frc1.facebook.com (Postfix, from userid 460691) id 19CDD252D7D8; Fri, 15 Apr 2022 21:30:26 -0700 (PDT) From: Kui-Feng Lee To: , , , , CC: Kui-Feng Lee Subject: [PATCH dwarves v6 3/6] bpf, x86: Attach a cookie to fentry/fexit/fmod_ret. Date: Fri, 15 Apr 2022 21:29:37 -0700 Message-ID: <20220416042940.656344-4-kuifeng@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220416042940.656344-1-kuifeng@fb.com> References: <20220416042940.656344-1-kuifeng@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-ORIG-GUID: JRGkNpB5RZdxBmk2x8GqFByCgwWfRydo X-Proofpoint-GUID: JRGkNpB5RZdxBmk2x8GqFByCgwWfRydo X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-04-16_01,2022-04-15_01,2022-02-23_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a bpf_cookie field to struct bpf_tracing_link to attach a cookie. The cookie of a bpf_tracing_link is available by calling bpf_get_attach_cookie when running the BPF program of the attached link. The value of a cookie will be set at bpf_tramp_run_ctx by the trampoline of the link. Signed-off-by: Kui-Feng Lee --- arch/x86/net/bpf_jit_comp.c | 12 ++++++++++-- include/linux/bpf.h | 1 + kernel/bpf/syscall.c | 10 +++++++--- kernel/trace/bpf_trace.c | 17 +++++++++++++++++ 4 files changed, 35 insertions(+), 5 deletions(-) diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index bf4576a6938c..52a5eba2d5e8 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1764,13 +1764,21 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog, struct bpf_tramp_link *l, int stack_size, bool save_ret) { + u64 cookie = 0; u8 *prog = *pprog; u8 *jmp_insn; int ctx_cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie); struct bpf_prog *p = l->link.prog; - /* mov rdi, 0 */ - emit_mov_imm64(&prog, BPF_REG_1, 0, 0); + if (l->link.type == BPF_LINK_TYPE_TRACING) { + struct bpf_tracing_link *tr_link = + container_of(l, struct bpf_tracing_link, link); + + cookie = tr_link->cookie; + } + + /* mov rdi, cookie */ + emit_mov_imm64(&prog, BPF_REG_1, (long) cookie >> 32, (u32) (long) cookie); /* Prepare struct bpf_tramp_run_ctx. * diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 1eae81df154e..45963972785b 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1060,6 +1060,7 @@ struct bpf_tracing_link { enum bpf_attach_type attach_type; struct bpf_trampoline *trampoline; struct bpf_prog *tgt_prog; + u64 cookie; }; struct bpf_link_primer { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 56e69a582b21..966f2d40ae55 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2697,7 +2697,8 @@ static const struct bpf_link_ops bpf_tracing_link_lops = { static int bpf_tracing_prog_attach(struct bpf_prog *prog, int tgt_prog_fd, - u32 btf_id) + u32 btf_id, + u64 bpf_cookie) { struct bpf_link_primer link_primer; struct bpf_prog *tgt_prog = NULL; @@ -2762,6 +2763,7 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog, bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING, &bpf_tracing_link_lops, prog); link->attach_type = prog->expected_attach_type; + link->cookie = bpf_cookie; mutex_lock(&prog->aux->dst_mutex); @@ -3058,7 +3060,7 @@ static int bpf_raw_tracepoint_open(const union bpf_attr *attr) tp_name = prog->aux->attach_func_name; break; } - err = bpf_tracing_prog_attach(prog, 0, 0); + err = bpf_tracing_prog_attach(prog, 0, 0, 0); if (err >= 0) return err; goto out_put_prog; @@ -4250,7 +4252,9 @@ static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr, else if (prog->type == BPF_PROG_TYPE_EXT) return bpf_tracing_prog_attach(prog, attr->link_create.target_fd, - attr->link_create.target_btf_id); + attr->link_create.target_btf_id, + 0); + return -EINVAL; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index b26f3da943de..c5713d5fba45 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1088,6 +1088,21 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = { .arg1_type = ARG_PTR_TO_CTX, }; +BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx) +{ + struct bpf_trace_run_ctx *run_ctx; + + run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); + return run_ctx->bpf_cookie; +} + +static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = { + .func = bpf_get_attach_cookie_tracing, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags) { #ifndef CONFIG_X86 @@ -1716,6 +1731,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL; case BPF_FUNC_get_func_arg_cnt: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL; + case BPF_FUNC_get_attach_cookie: + return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL; default: fn = raw_tp_prog_func_proto(func_id, prog); if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)