[PATCH 5.4 11/65] tools lib traceevent: Handle __attribute__((user)) in field names

From: Greg Kroah-Hartman
Date: Tue Jul 07 2020 - 11:20:14 EST


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

[ Upstream commit 74621d929d944529a5e2878a84f48bfa6fb69a66 ]

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>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Jaewon Kim <jaewon31.kim@xxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kees Kook <keescook@xxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-trace-devel@xxxxxxxxxxxxxxx
Link: http://lore.kernel.org/lkml/20200324200956.663647256@xxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 4bc3e1b906652..798284f511f16 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