From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
Found that calling tracefs_event_enable/disable() will match all content
of the passed in strings and not just what is passed in.
That is, if you have two events, "open" and "open2", and call
tracefs_event_enable(NULL, NULL, "open");
it will match both the "open" event as well as the "open2" event. This is
because the regex is open ended.
To fix this, add a '^' to the beginning of the match and a '$' to the end
(if they do not already exist).
Fixes: fc94d1a8 ("libtracefs: Add tracefs_event_enable/disable() API")
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
src/tracefs-events.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/src/tracefs-events.c b/src/tracefs-events.c
index 0fef64f..b6d3136 100644
--- a/src/tracefs-events.c
+++ b/src/tracefs-events.c
@@ -828,6 +828,26 @@ static int enable_disable_all(struct tracefs_instance *instance,
return ret < 0 ? ret : 0;
}
+static int make_regex(regex_t *re, const char *match)
+{
+ int len = strlen(match);
+ char str[len + 3];
+ char *p = &str[0];
+
+ if (!len || match[0] != '^')
+ *(p++) = '^';
+
+ strcpy(p, match);
+ p += len;
+
+ if (!len || match[len-1] != '$')
+ *(p++) = '$';
+
+ *p = '\0';
+
+ return regcomp(re, str, REG_ICASE|REG_NOSUB);
+}
+
static int event_enable_disable(struct tracefs_instance *instance,
const char *system, const char *event,
bool enable)
@@ -847,12 +867,13 @@ static int event_enable_disable(struct tracefs_instance *instance,
goto out_free;
if (system) {
+ ret = make_regex(&system_re, system);
ret = regcomp(&system_re, system, REG_ICASE|REG_NOSUB);
if (ret < 0)
goto out_free;
}
if (event) {
- ret = regcomp(&event_re, event, REG_ICASE|REG_NOSUB);
+ ret = make_regex(&event_re, event);
if (ret < 0) {
if (system)
regfree(&system_re);
--
2.29.2
|