From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Date: Tue, 30 Nov 2021 12:31:23 -0500
Subject: tracing/histograms: String compares should not care about signed
 values
Git-commit: 450fec13d9170127678f991698ac1a5b05c02e2f
Patch-mainline: v5.16-rc4
References: git-fixes

When comparing two strings for the "onmatch" histogram trigger, fields
that are strings use string comparisons, which do not care about being
signed or not.

Do not fail to match two string fields if one is unsigned char array and
the other is a signed char array.

Link: https://lore.kernel.org/all/20211129123043.5cfd687a@gandalf.local.home/

Cc: stable@vgerk.kernel.org
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Yafang Shao <laoar.shao@gmail.com>
Fixes: b05e89ae7cf3b ("tracing: Accept different type for synthetic event fields")
Reviewed-by: Masami Hiramatsu <mhiramatsu@kernel.org>
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Miroslav Benes <mbenes@suse.cz>
---
 kernel/trace/trace_events_hist.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 9555b8e1d1e3..319f9c8ca7e7 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -3757,7 +3757,7 @@ static int check_synth_field(struct synth_event *event,
 
 	if (strcmp(field->type, hist_field->type) != 0) {
 		if (field->size != hist_field->size ||
-		    field->is_signed != hist_field->is_signed)
+		    (!field->is_string && field->is_signed != hist_field->is_signed))
 			return -EINVAL;
 	}