From: Pengpeng Hou <pengpeng@iscas.ac.cn> stable inclusion from stable-v6.6.141 commit 9399a92989354e34086f9a5c379493217df83c5e category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9232 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 5ec1d1e97de134beed3a5b08235a60fc1c51af96 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Tengda Wu <wutengda2@huawei.com> --- kernel/trace/trace_events_hist.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index f22aa4afaa6d..b6c4e2f26e3f 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1349,12 +1349,14 @@ 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; -- 2.34.1