Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751792AbZIZIxN (ORCPT ); Sat, 26 Sep 2009 04:53:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751467AbZIZIxM (ORCPT ); Sat, 26 Sep 2009 04:53:12 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:60312 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751083AbZIZIxM (ORCPT ); Sat, 26 Sep 2009 04:53:12 -0400 Subject: Re: [RFC PATCH tracing/kprobes 4/5] perf: Support perf kprobe command for kprobe-event setup helper From: Steven Rostedt To: Masami Hiramatsu Cc: Frederic Weisbecker , Ingo Molnar , lkml , systemtap , DLE , Thomas Gleixner , Arnaldo Carvalho de Melo , Mike Galbraith , Paul Mackerras , Peter Zijlstra , Christoph Hellwig , Ananth N Mavinakayanahalli , Jim Keniston , "Frank Ch. Eigler" In-Reply-To: <20090925191546.12939.75278.stgit@omoto> References: <20090925191424.12939.91503.stgit@omoto> <20090925191546.12939.75278.stgit@omoto> Content-Type: text/plain Date: Sat, 26 Sep 2009 04:52:00 -0400 Message-Id: <1253955120.12145.2.camel@frodo> Mime-Version: 1.0 X-Mailer: Evolution 2.26.3 (2.26.3-1.fc11) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1775 Lines: 64 On Fri, 2009-09-25 at 12:15 -0700, Masami Hiramatsu wrote: > + > +#define MAX_CMDLEN 256 > + > +static int synthesize_probepoint(struct probe_point *pp) > +{ > + char *buf; > + int i, len, ret; > + pp->probes[0] = buf = (char *)calloc(MAX_CMDLEN, sizeof(char)); > + len = snprintf(buf, MAX_CMDLEN, "%s+%d", pp->function, pp->offset); What happens if func and offset is too big for MAX_CMDLEN? > + for (i = 0; i < pp->nr_args; i++) { Can you have a case where pp->nr_args == 0? > + ret = snprintf(&buf[len], MAX_CMDLEN - len, " %s", > + pp->args[i]); > + if (ret <= 0 || ret >= MAX_CMDLEN - len) { > + free(pp->probes[0]); > + return -E2BIG; > + } > + len += ret; > + } > + return pp->found = 1; > +} > + > +int cmd_kprobe(int argc, const char **argv, const char *prefix __used) > +{ > + int i, j, fd, ret, need_dwarf = 0; > + struct probe_point *pp; > + char buf[MAX_CMDLEN]; > + > + argc = parse_options(argc, argv, options, kprobe_usage, > + PARSE_OPT_STOP_AT_NON_OPTION); > + if (argc || session.nr_probe == 0) > + usage_with_options(kprobe_usage, options); > + > + /* Synthesize return probes */ > + for (j = 0; j < session.nr_probe; j++) { > + if (session.events[j][0] != 'r') { > + need_dwarf = 1; > + continue; > + } > + ret = synthesize_probepoint(&session.probes[j]); > + if (ret < 0) > + semantic_error("probe point is too long."); If we have no args but the func and offset is too big, then this does not catch it. But this depends on if we can have no args. -- Steve > + } > + > -- 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/