From patchwork Thu Jul 11 13:03:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Tzvetomir Stoyanov (VMware)" X-Patchwork-Id: 11039967 X-Patchwork-Delegate: rostedt@goodmis.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E07EF138D for ; Thu, 11 Jul 2019 13:03:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D08462882D for ; Thu, 11 Jul 2019 13:03:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C280628A5C; Thu, 11 Jul 2019 13:03:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 41D032882D for ; Thu, 11 Jul 2019 13:03:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728662AbfGKND3 (ORCPT ); Thu, 11 Jul 2019 09:03:29 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:33086 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728645AbfGKND2 (ORCPT ); Thu, 11 Jul 2019 09:03:28 -0400 Received: by mail-wr1-f67.google.com with SMTP id n9so6261793wru.0 for ; Thu, 11 Jul 2019 06:03:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pYGGMTBfPn7XURlfNC5AdC+Z92FhL7hQTWqdDPwy2fQ=; b=pCkf8UGl7ZhUBsUjprJODMcCyXPqwa3I8qtFzMz9Zl9vP5BzQsEsoRI7yh+1KoEfnH WpNMc7WOtMi8HQJtf9nPtmCkcaGw62bMNN4/MOubXkNQLrTHbK9ABywcEsmB68lWbXUo +6CUaUaRah5LAJZTJZ526wOnIZFP2ceykV+zTe1PWL048hk4exygUZ0YET6rE1GVqWb6 Cb4pSVaHJ6Qaiw8peqVboHSTLkJkVg3AhKXCkrqtiP2zbpHX8qXyfgA8iWlptwW1r/XE kFCVB8QL6OMKR385jzCiFW7tEa4E/Gyk/FeI/i12LmKwmzijsom4/3WxW99w2b++MaVG 0JQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pYGGMTBfPn7XURlfNC5AdC+Z92FhL7hQTWqdDPwy2fQ=; b=qWHOAEia5ExXYZWXBjCjS8Ah/PIVrhadLV/bgH39XKnZZ6aaisI6lvz8L4AkYgmw1v OV3HweVTfrDihfixgY9N50E+vY/2IFT/F27jFTiRPJzt6LYYHCiV1DxtSUPTx5zTrdWD 6yIqy1VQ6DHe6dbr+LfMSLaUmfdrno5W72DP9dEWbP93vJ21x2pKlD6if0gPMqvErZIy iqLX2kGU1psGXg7YHs2yd2ivnFsiVkpLMcmwarAvZtKKf1KBrB0rOqqYbazmXp/lL+wo WQWEVL6jJg/iVJnqJPjLYED9qFwuMZQSXIPmHQgpybiL38BoF43Bybza+dg3UWyIYE3n 0rAA== X-Gm-Message-State: APjAAAWONOAxNnuNGiRIWEHLbSN0rahm9eHhoXr7qFvAnuzf+E/gSXgy nHkI+1zFtypCJXmW0bV0Tb2i1pJp X-Google-Smtp-Source: APXvYqx35SyHmMhkYaePshZUJMSKecD1WEUek2dEpPh415jq8eTod5dyNxL6Tcl1mpxD9nuzo8Ze6A== X-Received: by 2002:adf:eb89:: with SMTP id t9mr5095875wrn.120.1562850205758; Thu, 11 Jul 2019 06:03:25 -0700 (PDT) Received: from oberon.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id y16sm5051490wrw.33.2019.07.11.06.03.24 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 11 Jul 2019 06:03:25 -0700 (PDT) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v4] trace-cmd: Add option to execute traced process as given user Date: Thu, 11 Jul 2019 16:03:24 +0300 Message-Id: <20190711130324.25139-1-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP A new trace-cmd record option is added: "--user". When it is set with combination of option -F, the traced process is executed in the context of the specified user. Suggested-by: Yordan Karadzhov (VMware) Signed-off-by: Tzvetomir Stoyanov (VMware) --- [ v4 changes: - Added check for strdup() failure. - Made input user string argument of change_user() and run_cmd() constant. v3 changes: "--user" does not depend on option -F, it works with any command, specified as trace-cmd argument. v2 changes: - Check for errors in change_user(). If an error occurs while changing the user, the message is printed and the traced process is not executed. ] Documentation/trace-cmd-record.1.txt | 4 +++ tracecmd/trace-record.c | 49 ++++++++++++++++++++++++++-- tracecmd/trace-usage.c | 1 + 3 files changed, 51 insertions(+), 3 deletions(-) diff --git a/Documentation/trace-cmd-record.1.txt b/Documentation/trace-cmd-record.1.txt index 4a59de9..6a0f975 100644 --- a/Documentation/trace-cmd-record.1.txt +++ b/Documentation/trace-cmd-record.1.txt @@ -122,6 +122,10 @@ OPTIONS *--mmap*:: Used with either *-F* or *-P*, save the traced process memory map into the trace.dat file. + +*--user*:: + Execute the specified *command* as given user. + *-C* 'clock':: Set the trace clock to "clock". diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c index 48081d4..af52a88 100644 --- a/tracecmd/trace-record.c +++ b/tracecmd/trace-record.c @@ -33,6 +33,8 @@ #include #include #include +#include +#include #include "version.h" #include "trace-local.h" @@ -208,6 +210,7 @@ struct common_record_context { struct buffer_instance *instance; const char *output; char *date2ts; + char *user; int data_flags; int record_all; @@ -1417,7 +1420,34 @@ static void trace_or_sleep(enum trace_type type) sleep(10); } -static void run_cmd(enum trace_type type, int argc, char **argv) +static int change_user(const char *user) +{ + struct passwd *pwd; + + if (!user) + return 0; + + pwd = getpwnam(user); + if (!pwd) + return -1; + if (initgroups(user, pwd->pw_gid) < 0) + return -1; + if (setgid(pwd->pw_gid) < 0) + return -1; + if (setuid(pwd->pw_uid) < 0) + return -1; + + if (setenv("HOME", pwd->pw_dir, 1) < 0) + return -1; + if (setenv("USER", pwd->pw_name, 1) < 0) + return -1; + if (setenv("LOGNAME", pwd->pw_name, 1) < 0) + return -1; + + return 0; +} + +static void run_cmd(enum trace_type type, const char *user, int argc, char **argv) { int status; int pid; @@ -1438,6 +1468,10 @@ static void run_cmd(enum trace_type type, int argc, char **argv) dup2(save_stdout, 1); close(save_stdout); } + + if (change_user(user) < 0) + die("Failed to change user to %s", user); + if (execvp(argv[0], argv)) { fprintf(stderr, "\n********************\n"); fprintf(stderr, " Unable to exec %s\n", argv[0]); @@ -4548,6 +4582,7 @@ void update_first_instance(struct buffer_instance *instance, int topt) } enum { + OPT_user = 243, OPT_mmap = 244, OPT_quiet = 245, OPT_debug = 246, @@ -4780,6 +4815,7 @@ static void parse_record_options(int argc, {"quiet", no_argument, NULL, OPT_quiet}, {"help", no_argument, NULL, '?'}, {"mmap", no_argument, NULL, OPT_mmap}, + {"user", required_argument, NULL, OPT_user}, {"module", required_argument, NULL, OPT_module}, {NULL, 0, NULL, 0} }; @@ -5011,6 +5047,11 @@ static void parse_record_options(int argc, case 'i': ignore_event_not_found = 1; break; + case OPT_user: + ctx->user = strdup(optarg); + if (!ctx->user) + die("Failed to allocate user name"); + break; case OPT_mmap: get_mmap = 1; break; @@ -5079,7 +5120,6 @@ static void parse_record_options(int argc, if (!ctx->filtered && ctx->instance->filter_mod) add_func(&ctx->instance->filter_funcs, ctx->instance->filter_mod, "*"); - if (filter_task && get_mmap) do_ptrace = 1; @@ -5097,6 +5137,9 @@ static void parse_record_options(int argc, "Did you mean 'record'?"); ctx->run_command = 1; } + if (ctx->user && !ctx->run_command) + warning("--user %s is ignored, no command is specified", + ctx->user); } static enum trace_type get_trace_cmd_type(enum trace_cmd cmd) @@ -5237,7 +5280,7 @@ static void record_trace(int argc, char **argv, } if (ctx->run_command) - run_cmd(type, (argc - optind) - 1, &argv[optind + 1]); + run_cmd(type, ctx->user, (argc - optind) - 1, &argv[optind + 1]); else { update_task_filter(); tracecmd_enable_tracing(); diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c index c658ede..e3e8186 100644 --- a/tracecmd/trace-usage.c +++ b/tracecmd/trace-usage.c @@ -58,6 +58,7 @@ static struct usage_help usage_help[] = { " --max-graph-depth limit function_graph depth\n" " --no-filter include trace-cmd threads in the trace\n" " --mmap used with -F or -P, save the traced process memory map into the trace.dat file\n" + " --user execute the specified [command ...] as given user\n" }, { "start",