From 36662794bb520be828df8e2f3404264f5e7a7973 Mon Sep 17 00:00:00 2001 From: Taeung Song Date: Fri, 4 Nov 2016 15:44:19 +0900 Subject: [PATCH] perf config: Validate config variable arguments before trying use them You can show the values for several config items as below: # perf config report.queue-size call-graph.record-mode but it is necessary to more precisely check arguments, before passing them to show_spec_config(). This validation function would be also used when parsing config key-value pairs arguments in the near future. Committer notes: Testing it: $ perf config bla. The config variable does not contain a variable name: bla. $ perf config .bla The config variable does not contain a section name: .bla $ perf config bla.bla $ Signed-off-by: Taeung Song Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Nambong Ha Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Cc: Wookje Kwon Link: http://lkml.kernel.org/r/1478241862-31230-4-git-send-email-treeze.taeung@gmail.com [ Fix some spelling errors ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-config.c | 45 +++++++++++++++++++++++++++++++++---- 1 file changed, 41 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-config.c b/tools/perf/builtin-config.c index df3fa1c18e55..88a43fe4963c 100644 --- a/tools/perf/builtin-config.c +++ b/tools/perf/builtin-config.c @@ -82,6 +82,27 @@ static int show_config(struct perf_config_set *set) return 0; } +static int parse_config_arg(char *arg, char **var) +{ + const char *last_dot = strchr(arg, '.'); + + /* + * Since "var" actually contains the section name and the real + * config variable name separated by a dot, we have to know where the dot is. + */ + if (last_dot == NULL || last_dot == arg) { + pr_err("The config variable does not contain a section name: %s\n", arg); + return -1; + } + if (!last_dot[1]) { + pr_err("The config variable does not contain a variable name: %s\n", arg); + return -1; + } + + *var = arg; + return 0; +} + int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused) { int i, ret = 0; @@ -130,10 +151,26 @@ int cmd_config(int argc, const char **argv, const char *prefix __maybe_unused) } break; default: - if (argc) - for (i = 0; argv[i]; i++) - ret = show_spec_config(set, argv[i]); - else + if (argc) { + for (i = 0; argv[i]; i++) { + char *var, *arg = strdup(argv[i]); + + if (!arg) { + pr_err("%s: strdup failed\n", __func__); + ret = -1; + break; + } + + if (parse_config_arg(arg, &var) < 0) { + free(arg); + ret = -1; + break; + } + + ret = show_spec_config(set, var); + free(arg); + } + } else usage_with_options(config_usage, config_options); }