Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933508AbZJLW12 (ORCPT ); Mon, 12 Oct 2009 18:27:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933498AbZJLW11 (ORCPT ); Mon, 12 Oct 2009 18:27:27 -0400 Received: from mail-ew0-f228.google.com ([209.85.219.228]:60369 "EHLO mail-ew0-f228.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758551AbZJLW0D (ORCPT ); Mon, 12 Oct 2009 18:26:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=qLdm9ITVBmjfIQC1uGaA1pgPqcX2mkbefAgE/3tlkeB3BBy70YLQwSaXZHZU91JPci ByymVee628nYdPW+tkNx7ksMQuXUzB4HsGQTqy8wSYak/5TBd7jUMb0i+kZdCCuQ3soN hUUV8hYwLe24fVIN/iYyNWW19PhxshR2lNkQw= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Masami Hiramatsu , Li Zefan , Frederic Weisbecker , Ingo Molnar , Thomas Gleixner , Arnaldo Carvalho de Melo , Steven Rostedt , Mike Galbraith , Paul Mackerras , Peter Zijlstra , Christoph Hellwig , Ananth N Mavinakayanahalli , Jim Keniston , "Frank Ch. Eigler" Subject: [PATCH 4/7] tracing/kprobes: Avoid field name confliction Date: Tue, 13 Oct 2009 00:25:06 +0200 Message-Id: <1255386309-4992-6-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 In-Reply-To: <1255386309-4992-1-git-send-email-fweisbec@gmail.com> References: <1255386309-4992-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5568 Lines: 169 From: Masami Hiramatsu Check whether the argument name is in conflict with other field names while creating a kprobe through the debugfs interface. Changes in v3: - Check strcmp() == 0 instead of !strcmp(). Changes in v2: - Add common_lock_depth to reserved name list. Signed-off-by: Masami Hiramatsu Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Arnaldo Carvalho de Melo Cc: Steven Rostedt Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Christoph Hellwig Cc: Ananth N Mavinakayanahalli Cc: Jim Keniston Cc: Frank Ch. Eigler LKML-Reference: <20091007222807.1684.26880.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Frederic Weisbecker --- kernel/trace/trace_kprobe.c | 65 +++++++++++++++++++++++++++++++++++-------- 1 files changed, 53 insertions(+), 12 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 3313fa7..bb6cb2b 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -38,6 +38,25 @@ #define MAX_EVENT_NAME_LEN 64 #define KPROBE_EVENT_SYSTEM "kprobes" +/* Reserved field names */ +#define FIELD_STRING_IP "ip" +#define FIELD_STRING_NARGS "nargs" +#define FIELD_STRING_RETIP "ret_ip" +#define FIELD_STRING_FUNC "func" + +const char *reserved_field_names[] = { + "common_type", + "common_flags", + "common_preempt_count", + "common_pid", + "common_tgid", + "common_lock_depth", + FIELD_STRING_IP, + FIELD_STRING_NARGS, + FIELD_STRING_RETIP, + FIELD_STRING_FUNC, +}; + /* currently, trace_kprobe only supports X86. */ struct fetch_func { @@ -537,6 +556,20 @@ static int parse_probe_arg(char *arg, struct fetch_func *ff, int is_return) return ret; } +/* Return 1 if name is reserved or already used by another argument */ +static int conflict_field_name(const char *name, + struct probe_arg *args, int narg) +{ + int i; + for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) + if (strcmp(reserved_field_names[i], name) == 0) + return 1; + for (i = 0; i < narg; i++) + if (strcmp(args[i].name, name) == 0) + return 1; + return 0; +} + static int create_trace_probe(int argc, char **argv) { /* @@ -637,6 +670,12 @@ static int create_trace_probe(int argc, char **argv) *arg++ = '\0'; else arg = argv[i]; + + if (conflict_field_name(argv[i], tp->args, i)) { + ret = -EINVAL; + goto error; + } + tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); /* Parse fetch argument */ @@ -1039,8 +1078,8 @@ static int kprobe_event_define_fields(struct ftrace_event_call *event_call) if (!ret) return ret; - DEFINE_FIELD(unsigned long, ip, "ip", 0); - DEFINE_FIELD(int, nargs, "nargs", 1); + DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); + DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1); /* Set argument names as fields */ for (i = 0; i < tp->nr_args; i++) DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0); @@ -1057,9 +1096,9 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) if (!ret) return ret; - DEFINE_FIELD(unsigned long, func, "func", 0); - DEFINE_FIELD(unsigned long, ret_ip, "ret_ip", 0); - DEFINE_FIELD(int, nargs, "nargs", 1); + DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); + DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); + DEFINE_FIELD(int, nargs, FIELD_STRING_NARGS, 1); /* Set argument names as fields */ for (i = 0; i < tp->nr_args; i++) DEFINE_FIELD(unsigned long, args[i], tp->args[i].name, 0); @@ -1108,15 +1147,16 @@ static int kprobe_event_show_format(struct ftrace_event_call *call, int ret, i; struct trace_probe *tp = (struct trace_probe *)call->data; - SHOW_FIELD(unsigned long, ip, "ip"); - SHOW_FIELD(int, nargs, "nargs"); + SHOW_FIELD(unsigned long, ip, FIELD_STRING_IP); + SHOW_FIELD(int, nargs, FIELD_STRING_NARGS); /* Show fields */ for (i = 0; i < tp->nr_args; i++) SHOW_FIELD(unsigned long, args[i], tp->args[i].name); trace_seq_puts(s, "\n"); - return __probe_event_show_format(s, tp, "(%lx)", "REC->ip"); + return __probe_event_show_format(s, tp, "(%lx)", + "REC->" FIELD_STRING_IP); } static int kretprobe_event_show_format(struct ftrace_event_call *call, @@ -1126,9 +1166,9 @@ static int kretprobe_event_show_format(struct ftrace_event_call *call, int ret, i; struct trace_probe *tp = (struct trace_probe *)call->data; - SHOW_FIELD(unsigned long, func, "func"); - SHOW_FIELD(unsigned long, ret_ip, "ret_ip"); - SHOW_FIELD(int, nargs, "nargs"); + SHOW_FIELD(unsigned long, func, FIELD_STRING_FUNC); + SHOW_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP); + SHOW_FIELD(int, nargs, FIELD_STRING_NARGS); /* Show fields */ for (i = 0; i < tp->nr_args; i++) @@ -1136,7 +1176,8 @@ static int kretprobe_event_show_format(struct ftrace_event_call *call, trace_seq_puts(s, "\n"); return __probe_event_show_format(s, tp, "(%lx <- %lx)", - "REC->func, REC->ret_ip"); + "REC->" FIELD_STRING_FUNC + ", REC->" FIELD_STRING_RETIP); } #ifdef CONFIG_EVENT_PROFILE -- 1.6.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/