The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From c8d94a1878342fdffedaaf15201d951dfc147065 Mon Sep 17 00:00:00 2001
From: Tom Zanussi tom.zanussi@linux.intel.com Date: Thu, 18 Apr 2019 10:18:51 -0500 Subject: [PATCH] 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...
Cc: stable@vger.kernel.org Fixes: 067fe038e70f6 ("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
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 06e7b9f66de6..2b76f9520bd0 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -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;