tracing/filters: operand can be negative

This should be a bug:

 # cat format
 name: foo_bar
 ID: 71
 format:
	 ...
         field:int bar;  offset:24;      size:4;
 # echo 'bar < 0' > filter
 # echo 'bar < -1' > filter
 bash: echo: write error: Invalid argument

[ Impact: fix to allow negative operand in filer expr ]

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A35B8DF.60400@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index db6e54bdb596..1d8192304842 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -546,6 +546,7 @@ static int filter_add_pred(struct filter_parse_state *ps,
         filter_pred_fn_t fn;
         unsigned long long val;
         int string_type;
+        int ret;
 
         pred->fn = filter_pred_none;
 
@@ -581,7 +582,11 @@ static int filter_add_pred(struct filter_parse_state *ps,
                         pred->not = 1;
                 return filter_add_pred_fn(ps, call, pred, fn);
         } else {
-                if (strict_strtoull(pred->str_val, 0, &val)) {
+                if (field->is_signed)
+                        ret = strict_strtoll(pred->str_val, 0, &val);
+                else
+                        ret = strict_strtoull(pred->str_val, 0, &val);
+                if (ret) {
                         parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
                         return -EINVAL;
                 }