From 85fc95d75970ee7dd8e01904e7fb1197c275ba6b Mon Sep 17 00:00:00 2001
From: Cengiz Can <cengiz@kernel.wtf>
Date: Mon, 20 Jan 2020 17:15:54 +0300
Subject: perf maps: Add missing unlock to maps__insert() error case

From: Cengiz Can <cengiz@kernel.wtf>

commit 85fc95d75970ee7dd8e01904e7fb1197c275ba6b upstream.

`tools/perf/util/map.c` has a function named `maps__insert` that
acquires a write lock if its in multithread context.

Even though this lock is released when function successfully completes,
there's a branch that is executed when `maps_by_name == NULL` that
returns from this function without releasing the write lock.

Added an `up_write` to release the lock when this happens.

Fixes: a7c2b572e217 ("perf map_groups: Auto sort maps by name, if needed")
Signed-off-by: Cengiz Can <cengiz@kernel.wtf>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200120141553.23934-1-cengiz@kernel.wtf
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 tools/perf/util/map.c |    1 +
 1 file changed, 1 insertion(+)

--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -549,6 +549,7 @@ void maps__insert(struct maps *maps, str
 
 			if (maps_by_name == NULL) {
 				__maps__free_maps_by_name(maps);
+				up_write(&maps->lock);
 				return;
 			}