From mboxrd@z Thu Jan 1 00:00:00 1970 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 F0476C433FE for ; Thu, 3 Nov 2022 04:55:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229951AbiKCEzY (ORCPT ); Thu, 3 Nov 2022 00:55:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230324AbiKCEzO (ORCPT ); Thu, 3 Nov 2022 00:55:14 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FE0817E1E for ; Wed, 2 Nov 2022 21:55:12 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-3697bd55974so8558307b3.15 for ; Wed, 02 Nov 2022 21:55:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=L+kjIEex1IOYklacrKrannRwY39rvITMzPAwz++9RgI=; b=MbZZjsEj3+nFozyRBV019hV+y7Be8O3uF+CKCcqtsrqy27tDZlQtVy5xGmpuE4sxQr RcWvOZrouGE58XuTg9LRy5Ry96JSoAtsD3bWe+ir4DpZ+CjmF8MQVmYxxNitL0J+8I32 rtYVCyV/H6PsZ8rN4U2y5Wjcxxi8rMElcx3y4uaqv5jZXnbv42X8Zwy8G5D7tMf5+Je5 gG71UwrCBg0wr+C1cvunD6WWaDQxdkGUuODvKNvuVffSEL2MHbpYxMQY1lj6Zp7439nt RP75mbPe86+o4fWsMvIjP4csuuRqXhxHEJz8xH/VSyaqVx/jali+oZEwThtoh9z4B8by n4BA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=L+kjIEex1IOYklacrKrannRwY39rvITMzPAwz++9RgI=; b=s38YmNufJf6ghWQOvyGRpiTGW0qnqH9593D3V3T9y8s22/ajxrJBLZOxSzfWcNJ+Hf lNKEnA9kaSDplMmEyPhqnY60QtZz2ARO/r2WPdV6iWqYszc2ACQRoDCIyw5flh094mwC vGvzgNa5Pt73Y86WIZapNdTtJ9xA41oKMQJCZKvoUHUm7s5UQ/gukYEKNVCOPkX4Mnjt WDA2nvUXbEqCND0hGNWu2VVGdnzJtDgoBansADzv6tdq6riJctIKXMXYvB+Lc6ygXEAB JrB9yB5yECNzF4PTjRfrJjYxJYgPJsw1vq8dtcQ+6FaXqduVs/uLqbGj1z/GET5rCEbs xxNA== X-Gm-Message-State: ACrzQf3qP1G5A3DQbdtnP77olgnsfYgk6SsO+bFb4JEhWdZl50/ZWacx DQwogeLrogdz0h4oOXhC0HlVJqoVTa8x X-Google-Smtp-Source: AMsMyM4iIn9a02aMdt6yZsX7DM1HL5tNqHhhuvpC8PkwISePPR39xcxiulhZgC0WZUUsv8vdSfkf2rcek0s5 X-Received: from irogers.svl.corp.google.com ([2620:15c:2d4:203:8a9d:7f38:6465:2d7b]) (user=irogers job=sendgmr) by 2002:a0d:d84c:0:b0:36b:40f4:7989 with SMTP id a73-20020a0dd84c000000b0036b40f47989mr26806136ywe.432.1667451311498; Wed, 02 Nov 2022 21:55:11 -0700 (PDT) Date: Wed, 2 Nov 2022 21:54:33 -0700 In-Reply-To: <20221103045437.163510-1-irogers@google.com> Message-Id: <20221103045437.163510-4-irogers@google.com> Mime-Version: 1.0 References: <20221103045437.163510-1-irogers@google.com> X-Mailer: git-send-email 2.38.1.273.g43a17bfeac-goog Subject: [PATCH v1 3/7] perf trace: Augmented syscalls fix libbpf 1.0+ compatibility From: Ian Rogers To: Leo Yan , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Stephane Eranian , Ian Rogers Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Don't use deprecated and now broken map style. Avoid use of tools/perf/include/bpf/bpf.h and use the more regular BPF headers. Add "< 0" checks to fix BPF verifier failures about potentially negative values being passed to bpf_perf_event_output replacing an existing mask. Add a raw_syscalls:sys_enter to avoid the evlist being empty and causing perf trace to exit during argument parsing. Signed-off-by: Ian Rogers --- tools/perf/examples/bpf/augmented_syscalls.c | 58 ++++++++++++++------ 1 file changed, 41 insertions(+), 17 deletions(-) diff --git a/tools/perf/examples/bpf/augmented_syscalls.c b/tools/perf/examples/bpf/augmented_syscalls.c index 524fdb8534b3..a809e1eab95d 100644 --- a/tools/perf/examples/bpf/augmented_syscalls.c +++ b/tools/perf/examples/bpf/augmented_syscalls.c @@ -16,11 +16,17 @@ * contents of pointer arguments. */ -#include -#include +#include +#include +#include /* bpf-output associated map */ -bpf_map(__augmented_syscalls__, PERF_EVENT_ARRAY, int, u32, __NR_CPUS__); +struct __augmented_syscalls__ { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __type(key, int); + __type(value, __u32); + __uint(max_entries, __NR_CPUS__); +} __augmented_syscalls__ SEC(".maps"); struct syscall_exit_args { unsigned long long common_tp_fields; @@ -34,6 +40,12 @@ struct augmented_filename { char value[256]; }; +#define syscall_enter(name) \ + SEC("!syscalls:sys_enter_" #name) syscall_enter_ ## name + +#define syscall_exit(name) \ + SEC("!syscalls:sys_exit_" #name) syscall_exit_ ## name + #define augmented_filename_syscall(syscall) \ struct augmented_enter_##syscall##_args { \ struct syscall_enter_##syscall##_args args; \ @@ -42,18 +54,23 @@ struct augmented_enter_##syscall##_args { \ int syscall_enter(syscall)(struct syscall_enter_##syscall##_args *args) \ { \ struct augmented_enter_##syscall##_args augmented_args = { .filename.reserved = 0, }; \ - unsigned int len = sizeof(augmented_args); \ - probe_read(&augmented_args.args, sizeof(augmented_args.args), args); \ - augmented_args.filename.size = probe_read_str(&augmented_args.filename.value, \ + long size; \ + \ + if (bpf_probe_read(&augmented_args.args, sizeof(augmented_args.args), args) < 0) \ + return -1; \ + \ + size = bpf_probe_read_str(&augmented_args.filename.value, \ sizeof(augmented_args.filename.value), \ args->filename_ptr); \ - if (augmented_args.filename.size < sizeof(augmented_args.filename.value)) { \ - len -= sizeof(augmented_args.filename.value) - augmented_args.filename.size; \ - len &= sizeof(augmented_args.filename.value) - 1; \ - } \ + if (size < 0) \ + return -1; \ + \ + augmented_args.filename.size = size; \ /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */ \ - return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, \ - &augmented_args, len); \ + return bpf_perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, \ + &augmented_args, \ + (sizeof(augmented_args) - sizeof(augmented_args.filename.value) + \ + size)); \ } \ int syscall_exit(syscall)(struct syscall_exit_args *args) \ { \ @@ -106,7 +123,7 @@ augmented_filename_syscall(newstat); #define _K_SS_MAXSIZE 128 #endif -#define augmented_sockaddr_syscall(syscall) \ +#define augmented_sockaddr_syscall(syscall) \ struct augmented_enter_##syscall##_args { \ struct syscall_enter_##syscall##_args args; \ struct sockaddr_storage addr; \ @@ -115,14 +132,14 @@ int syscall_enter(syscall)(struct syscall_enter_##syscall##_args *args) \ { \ struct augmented_enter_##syscall##_args augmented_args; \ unsigned long addrlen = sizeof(augmented_args.addr); \ - probe_read(&augmented_args.args, sizeof(augmented_args.args), args); \ + bpf_probe_read(&augmented_args.args, sizeof(augmented_args.args), args); \ /* FIXME_CLANG_OPTIMIZATION_THAT_ACCESSES_USER_CONTROLLED_ADDRLEN_DESPITE_THIS_CHECK */ \ /* if (addrlen > augmented_args.args.addrlen) */ \ /* addrlen = augmented_args.args.addrlen; */ \ /* */ \ - probe_read(&augmented_args.addr, addrlen, args->addr_ptr); \ + bpf_probe_read(&augmented_args.addr, addrlen, args->addr_ptr); \ /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */ \ - return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, \ + return bpf_perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, \ &augmented_args, \ sizeof(augmented_args) - sizeof(augmented_args.addr) + addrlen);\ } \ @@ -166,4 +183,11 @@ struct syscall_enter_sendto_args { augmented_sockaddr_syscall(sendto); -license(GPL); +struct syscall_enter_args; + +SEC("raw_syscalls:sys_enter") +int sys_enter(struct syscall_enter_args *args) +{ + return 0; +} +char _license[] SEC("license") = "GPL"; -- 2.38.1.273.g43a17bfeac-goog