[PATCH 2/3] tools lib traceevent: Handle __attribute__((user)) in field names

From: Steven Rostedt
Date: Tue Mar 24 2020 - 16:10:00 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

Commit c61f13eaa1ee1 ("gcc-plugins: Add structleak for more stack
initialization") added "__attribute__((user))" to the user when stackleak
detector is enabled. This now appears in the field format of system call
trace events for system calls that have user buffers. The
"__attribute__((user))" breaks the parsing in libtraceevent. That needs to
be handled.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
tools/lib/traceevent/event-parse.c | 39 +++++++++++++++++++++++++++++-
1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index eec96c31ea9e..010e60d5a081 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -1444,6 +1444,7 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
enum tep_event_type type;
char *token;
char *last_token;
+ char *delim = " ";
int count = 0;
int ret;

@@ -1504,13 +1505,49 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field **
field->flags |= TEP_FIELD_IS_POINTER;

if (field->type) {
- ret = append(&field->type, " ", last_token);
+ ret = append(&field->type, delim, last_token);
free(last_token);
if (ret < 0)
goto fail;
} else
field->type = last_token;
last_token = token;
+ delim = " ";
+ continue;
+ }
+
+ /* Handle __attribute__((user)) */
+ if ((type == TEP_EVENT_DELIM) &&
+ strcmp("__attribute__", last_token) == 0 &&
+ token[0] == '(') {
+ int depth = 1;
+ int ret;
+
+ ret = append(&field->type, " ", last_token);
+ ret |= append(&field->type, "", "(");
+ if (ret < 0)
+ goto fail;
+
+ delim = " ";
+ while ((type = read_token(&token)) != TEP_EVENT_NONE) {
+ if (type == TEP_EVENT_DELIM) {
+ if (token[0] == '(')
+ depth++;
+ else if (token[0] == ')')
+ depth--;
+ if (!depth)
+ break;
+ ret = append(&field->type, "", token);
+ delim = "";
+ } else {
+ ret = append(&field->type, delim, token);
+ delim = " ";
+ }
+ if (ret < 0)
+ goto fail;
+ free(last_token);
+ last_token = token;
+ }
continue;
}
break;
--
2.25.1