1 files changed, 43 insertions, 0 deletions
diff --git a/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh b/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh
new file mode 100755
index 000000000000..64c5d8c518a4
--- /dev/null
+++ b/tools/testing/selftests/damon/sysfs_memcg_path_leak.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+if [ $EUID -ne 0 ]
+then
+	echo "Run as root"
+	exit $ksft_skip
+fi
+
+damon_sysfs="/sys/kernel/mm/damon/admin"
+if [ ! -d "$damon_sysfs" ]
+then
+	echo "damon sysfs not found"
+	exit $ksft_skip
+fi
+
+# ensure filter directory
+echo 1 > "$damon_sysfs/kdamonds/nr_kdamonds"
+echo 1 > "$damon_sysfs/kdamonds/0/contexts/nr_contexts"
+echo 1 > "$damon_sysfs/kdamonds/0/contexts/0/schemes/nr_schemes"
+echo 1 > "$damon_sysfs/kdamonds/0/contexts/0/schemes/0/filters/nr_filters"
+
+filter_dir="$damon_sysfs/kdamonds/0/contexts/0/schemes/0/filters/0"
+
+before_kb=$(grep Slab /proc/meminfo | awk '{print $2}')
+
+# try to leak 3000 KiB
+for i in {1..102400};
+do
+	echo "012345678901234567890123456789" > "$filter_dir/memcg_path"
+done
+
+after_kb=$(grep Slab /proc/meminfo | awk '{print $2}')
+# expect up to 1500 KiB free from other tasks memory
+expected_after_kb_max=$((before_kb + 1500))
+
+if [ "$after_kb" -gt "$expected_after_kb_max" ]
+then
+	echo "maybe memcg_path are leaking: $before_kb -> $after_kb"
+	exit 1
+else
+	exit 0
+fi