Commit c8d94a18 authored Apr 18, 2019 by Tom Zanussi Committed by Steven Rostedt (VMware) May 21, 2019

tracing: Check keys for variable references in expressions too

There's an existing check for variable references in keys, but it
doesn't go far enough. It checks whether a key field is a variable
reference but doesn't check whether it's an expression containing
variable references, which can cause the same problems for callers.

Use the existing field_has_hist_vars() function rather than a direct
top-level flag check to catch all possible variable references.

Link: http://lkml.kernel.org/r/e8c3d3d53db5ca90ceea5a46e5413103a6902fc7.1555597045.git.tom.zanussi@linux.intel.com

Cc: stable@vger.kernel.org
Fixes: 067fe038 ("tracing: Add variable reference handling to hist triggers")
Reported-by: Vincent Bernat <vincent@bernat.ch>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

parent 55267c88

kernel/trace/trace_events_hist.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -59,7 +59,7 @@
		C(NO_CLOSING_PAREN, "No closing paren found"), \
		C(SUBSYS_NOT_FOUND, "Missing subsystem"), \
		C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \
		C(INVALID_REF_KEY, "Using variable references as keys not supported"), \
		C(INVALID_REF_KEY, "Using variable references in keys not supported"), \
		C(VAR_NOT_FOUND, "Couldn't find variable"), \
		C(FIELD_NOT_FOUND, "Couldn't find field"),

		@@ -4506,7 +4506,7 @@ static int create_key_field(struct hist_trigger_data *hist_data,
		goto out;
		}

		if (hist_field->flags & HIST_FIELD_FL_VAR_REF) {
		if (field_has_hist_vars(hist_field, 0)) {
		hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
		destroy_hist_field(hist_field, 0);
		ret = -EINVAL;