linux-kernel - [PATCH v2 3/6] perf-probe: Accept FUNC@* to specify function name explicitly

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID:  <173099115149.2431889.13682110856853358354.stgit@mhiramat.roam.corp.google.com>
Date: Thu,  7 Nov 2024 23:52:31 +0900
From: "Masami Hiramatsu (Google)" <mhiramat@...nel.org>
To: Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>
Cc: Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	Ian Rogers <irogers@...gle.com>,
	Dima Kogan <dima@...retsauce.net>,
	Alexander Lobakin <aleksander.lobakin@...el.com>,
	Przemek Kitszel <przemyslaw.kitszel@...el.com>,
	linux-perf-users@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH v2 3/6] perf-probe: Accept FUNC@* to specify function name explicitly

From: Masami Hiramatsu (Google) <mhiramat@...nel.org>

In Golang, the function name will have the '.', and perf probe
misinterpret it is a file name. To mitigate this situation, introduce
`function@*` so that user can explicitly specify that is a function
name.

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@...nel.org>
---
 Changes in v2:
  - Added new patch.
---
 tools/perf/util/probe-event.c |   22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index edc205e4b0ee..777ef00f0d3f 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1357,6 +1357,8 @@ static bool is_c_func_name(const char *name)
  *
  *         SRC[:SLN[+NUM|-ELN]]
  *         FNC[@SRC][:SLN[+NUM|-ELN]]
+ *
+ * FNC@SRC accepts `FNC@*` which forcibly specify FNC as function name.
  */
 int parse_line_range_desc(const char *arg, struct line_range *lr)
 {
@@ -1412,13 +1414,21 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 
 	file = strpbrk_esc(name, "@");
 	if (file) {
-		*file = '\0';
-		lr->file = strdup(++file);
-		if (lr->file == NULL) {
-			err = -ENOMEM;
+		*file++ = '\0';
+		if (strcmp(file, "*")) {
+			lr->file = strdup_esc(file);
+			if (lr->file == NULL) {
+				err = -ENOMEM;
+				goto err;
+			}
+		}
+		if (*name != '\0')
+			lr->function = name;
+		if (!lr->function && !lr->file) {
+			semantic_error("Only '@*' is not allowed.\n");
+			err = -EINVAL;
 			goto err;
 		}
-		lr->function = name;
 	} else if (strpbrk_esc(name, "/."))
 		lr->file = name;
 	else if (is_c_func_name(name))/* We reuse it for checking funcname */
@@ -1619,6 +1629,8 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
 				semantic_error("SRC@SRC is not allowed.\n");
 				return -EINVAL;
 			}
+			if (!strcmp(arg, "*"))
+				break;
 			pp->file = strdup_esc(arg);
 			if (pp->file == NULL)
 				return -ENOMEM;