tracing/filters: allow user-input to be integer-like string

Suppose we would like to trace all tasks named '123', but this
will fail:

 # echo 'parent_comm == 123' > events/sched/sched_process_fork/filter
 bash: echo: write error: Invalid argument

Don't guess the type of the filter pred in filter_parse(), but instead
we check it in __filter_add_pred().

[ Impact: extend allowed filter field string values ]

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49ED8DEB.6000700@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Li Zefan 2009-04-21 17:12:11 +08:00 committed by Ingo Molnar
parent e8082f3f5a
commit f66578a763

View File

@ -313,6 +313,7 @@ static int __filter_add_pred(struct ftrace_event_call *call,
{
struct ftrace_event_field *field;
filter_pred_fn_t fn;
unsigned long long val;
field = find_event_field(call, pred->field_name);
if (!field)
@ -322,14 +323,13 @@ static int __filter_add_pred(struct ftrace_event_call *call,
pred->offset = field->offset;
if (is_string_field(field->type)) {
if (!pred->str_len)
return -EINVAL;
fn = filter_pred_string;
pred->str_len = field->size;
return filter_add_pred_fn(call, pred, fn);
} else {
if (pred->str_len)
if (strict_strtoull(pred->str_val, 0, &val))
return -EINVAL;
pred->val = val;
}
switch (field->size) {
@ -413,12 +413,16 @@ int filter_add_subsystem_pred(struct event_subsystem *system,
return 0;
}
/*
* The filter format can be
* - 0, which means remove all filter preds
* - [||/&&] <field> ==/!= <val>
*/
int filter_parse(char **pbuf, struct filter_pred *pred)
{
char *tmp, *tok, *val_str = NULL;
char *tok, *val_str = NULL;
int tok_n = 0;
/* field ==/!= number, or/and field ==/!= number, number */
while ((tok = strsep(pbuf, " \n"))) {
if (tok_n == 0) {
if (!strcmp(tok, "0")) {
@ -478,19 +482,13 @@ int filter_parse(char **pbuf, struct filter_pred *pred)
return -EINVAL;
}
strcpy(pred->str_val, val_str);
pred->str_len = strlen(val_str);
pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
if (!pred->field_name)
return -ENOMEM;
pred->str_len = 0;
pred->val = simple_strtoull(val_str, &tmp, 0);
if (tmp == val_str) {
strncpy(pred->str_val, val_str, MAX_FILTER_STR_VAL);
pred->str_len = strlen(val_str);
pred->str_val[pred->str_len] = '\0';
} else if (*tmp != '\0')
return -EINVAL;
return 0;
}