From patchwork Mon Jul 31 07:31:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13333940 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 21051C001DE for ; Mon, 31 Jul 2023 07:32:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231649AbjGaHcq (ORCPT ); Mon, 31 Jul 2023 03:32:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231485AbjGaHcC (ORCPT ); Mon, 31 Jul 2023 03:32:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8FC5170C; Mon, 31 Jul 2023 00:31:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D478760F29; Mon, 31 Jul 2023 07:31:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5B9E1C433C8; Mon, 31 Jul 2023 07:31:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690788677; bh=gcAsXcNpHr2neQoiFwF9exmEBvK8RQO7NJB0uoPDuFA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PJCNZ8PJXZUOqESsO0CQvvqa2vbqiqGdT78s1Kndn+r65NM4ua0ImO263GojFQAff a+V/S6unQvLrqL4T35+oxqQZ2bvUq6GNIiclwu55ZhebUHHCWW9pP1GwsG5AW95NYZ lYd/Pgw+7nNR0aJktmDw5qYQDjAYkYhQfedHZsIvUWgAR1f5GfiiwU41+kGIf9Bm5Y kJkb3nppK+uoXOrjLq5WY5TgOeeWVTN8eAM1XydYC81tjYt/avbOv9ZtAlXpQyBf/e HKEgGzBpWG1psJoyQGQgzwrUPKaHUyNvvsC5SzRh6lqitV7W1u3uGLK1EDDl2RDfiE ZvdrF4kY8i9sQ== From: "Masami Hiramatsu (Google)" To: linux-trace-kernel@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Steven Rostedt , mhiramat@kernel.org, Martin KaFai Lau , bpf@vger.kernel.org, Sven Schnelle , Alexei Starovoitov Subject: [PATCH v4 7/9] tracing/fprobe-event: Assume fprobe is a return event by $retval Date: Mon, 31 Jul 2023 16:31:12 +0900 Message-Id: <169078867246.173706.10461108619228856719.stgit@devnote2> X-Mailer: git-send-email 2.34.1 In-Reply-To: <169078860386.173706.3091034523220945605.stgit@devnote2> References: <169078860386.173706.3091034523220945605.stgit@devnote2> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: Masami Hiramatsu (Google) Assume the fprobe event is a return event if there is $retval is used in the probe's argument without %return. e.g. echo 'f:myevent vfs_read $retval' >> dynamic_events then 'myevent' is a return probe event. Suggested-by: Steven Rostedt Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/trace_fprobe.c | 58 +++++++++++++++----- .../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 2 - 2 files changed, 45 insertions(+), 15 deletions(-) diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 8f43f1f65b1b..8bfe23af9c73 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -898,6 +898,46 @@ static struct tracepoint *find_tracepoint(const char *tp_name) return data.tpoint; } +static int parse_symbol_and_return(int argc, const char *argv[], + char **symbol, bool *is_return, + bool is_tracepoint) +{ + char *tmp = strchr(argv[1], '%'); + int i; + + if (tmp) { + int len = tmp - argv[1]; + + if (!is_tracepoint && !strcmp(tmp, "%return")) { + *is_return = true; + } else { + trace_probe_log_err(len, BAD_ADDR_SUFFIX); + return -EINVAL; + } + *symbol = kmemdup_nul(argv[1], len, GFP_KERNEL); + } else + *symbol = kstrdup(argv[1], GFP_KERNEL); + if (!*symbol) + return -ENOMEM; + + if (*is_return) + return 0; + + /* If there is $retval, this should be a return fprobe. */ + for (i = 2; i < argc; i++) { + tmp = strstr(argv[i], "$retval"); + if (tmp && !isalnum(tmp[7]) && tmp[7] != '_') { + *is_return = true; + /* + * NOTE: Don't check is_tracepoint here, because it will + * be checked when the argument is parsed. + */ + break; + } + } + return 0; +} + static int __trace_fprobe_create(int argc, const char *argv[]) { /* @@ -927,7 +967,7 @@ static int __trace_fprobe_create(int argc, const char *argv[]) struct trace_fprobe *tf = NULL; int i, len, new_argc = 0, ret = 0; bool is_return = false; - char *symbol = NULL, *tmp = NULL; + char *symbol = NULL; const char *event = NULL, *group = FPROBE_EVENT_SYSTEM; const char **new_argv = NULL; int maxactive = 0; @@ -983,20 +1023,10 @@ static int __trace_fprobe_create(int argc, const char *argv[]) trace_probe_log_set_index(1); /* a symbol(or tracepoint) must be specified */ - symbol = kstrdup(argv[1], GFP_KERNEL); - if (!symbol) - return -ENOMEM; + ret = parse_symbol_and_return(argc, argv, &symbol, &is_return, is_tracepoint); + if (ret < 0) + goto parse_error; - tmp = strchr(symbol, '%'); - if (tmp) { - if (!is_tracepoint && !strcmp(tmp, "%return")) { - *tmp = '\0'; - is_return = true; - } else { - trace_probe_log_err(tmp - symbol, BAD_ADDR_SUFFIX); - goto parse_error; - } - } if (!is_return && maxactive) { trace_probe_log_set_index(0); trace_probe_log_err(1, BAD_MAXACT_TYPE); diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc index 812f5b3f6055..72563b2e0812 100644 --- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc +++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc @@ -30,11 +30,11 @@ check_error 'f:^ vfs_read' # NO_EVENT_NAME check_error 'f:foo/^12345678901234567890123456789012345678901234567890123456789012345 vfs_read' # EVENT_TOO_LONG check_error 'f:foo/^bar.1 vfs_read' # BAD_EVENT_NAME -check_error 'f vfs_read ^$retval' # RETVAL_ON_PROBE check_error 'f vfs_read ^$stack10000' # BAD_STACK_NUM check_error 'f vfs_read ^$arg10000' # BAD_ARG_NUM +check_error 'f vfs_read $retval ^$arg1' # BAD_VAR check_error 'f vfs_read ^$none_var' # BAD_VAR check_error 'f vfs_read ^'$REG # BAD_VAR