diff options
| author | Pengpeng Hou <pengpeng@iscas.ac.cn> | 2026-04-01 19:22:23 +0800 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2026-04-14 04:59:33 -0400 |
| commit | 5ec1d1e97de134beed3a5b08235a60fc1c51af96 (patch) | |
| tree | 818c6150cbcdb9b5461637be5cd2a6282f95b531 /kernel | |
| parent | 0ec6be95351b00ca95b39e8f0c6bbe0a9615f990 (diff) | |
tracing: Rebuild full_name on each hist_field_name() call
hist_field_name() uses a static MAX_FILTER_STR_VAL buffer for fully
qualified variable-reference names, but it currently appends into that
buffer with strcat() without rebuilding it first. As a result, repeated
calls append a new "system.event.field" name onto the previous one,
which can eventually run past the end of full_name.
Build the name with snprintf() on each call and return NULL if the fully
qualified name does not fit in MAX_FILTER_STR_VAL.
Link: https://patch.msgid.link/20260401112224.85582-1-pengpeng@iscas.ac.cn
Fixes: 067fe038e70f ("tracing: Add variable reference handling to hist triggers")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_events_hist.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 67cb92310864..b2b675c7d663 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1361,12 +1361,14 @@ static const char *hist_field_name(struct hist_field *field, field->flags & HIST_FIELD_FL_VAR_REF) { if (field->system) { static char full_name[MAX_FILTER_STR_VAL]; + int len; + + len = snprintf(full_name, sizeof(full_name), "%s.%s.%s", + field->system, field->event_name, + field->name); + if (len >= sizeof(full_name)) + return NULL; - strcat(full_name, field->system); - strcat(full_name, "."); - strcat(full_name, field->event_name); - strcat(full_name, "."); - strcat(full_name, field->name); field_name = full_name; } else field_name = field->name; |