[PATCH blktests 4/5] tests/throtl: add a new test 004

[Yu Kuai <yukuai1@huaweicloud.com>]

From: Yu Kuai <yukuai3@huawei.com>

Test delete the disk while IO is throttled, regerssion test for:

commit 884f0e84f1e3 ("blk-throttle: fix UAF by deleteing timer in blk_throtl_exit()")
commit 8f9e7b65f833 ("block: cancel all throttled bios in del_gendisk()")

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
 tests/throtl/004     | 79 ++++++++++++++++++++++++++++++++++++++++++++
 tests/throtl/004.out |  4 +++
 2 files changed, 83 insertions(+)
 create mode 100755 tests/throtl/004
 create mode 100644 tests/throtl/004.out

diff --git a/tests/throtl/004 b/tests/throtl/004
new file mode 100755
index 0000000..d07f9d5
--- /dev/null
+++ b/tests/throtl/004
@@ -0,0 +1,79 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2024 Yu Kuai
+#
+# Test delete the disk while IO is throttled, regerssion test for
+# commit 884f0e84f1e3 ("blk-throttle: fix UAF by deleteing timer in blk_throtl_exit()")
+# commit 8f9e7b65f833 ("block: cancel all throttled bios in del_gendisk()")
+
+. tests/throtl/rc
+
+DESCRIPTION="delete disk while IO is throttled"
+QUICK=1
+
+CG=/sys/fs/cgroup
+TEST_DIR=$CG/blktests_throtl
+devname=nullb0
+dev=""
+
+set_up_test() {
+	if ! _init_null_blk nr_devices=0; then
+		return 1;
+	fi
+
+	if ! _configure_null_blk $devname power=1; then
+		return 1;
+	fi
+
+	dev=$(cat /sys/block/$devname/dev)
+	echo +io > $CG/cgroup.subtree_control
+	mkdir $TEST_DIR
+
+	return 0;
+}
+
+clean_up_test() {
+	rmdir $TEST_DIR
+	echo -io > $CG/cgroup.subtree_control
+	_exit_null_blk
+}
+
+config_throtl() {
+	limit=$((1024 * 1024))
+	echo "$dev wbps=$limit" > $TEST_DIR/io.max
+}
+
+test_io() {
+	config_throtl
+
+	{
+		sleep 0.1
+		start_time=$(date +%s.%N)
+
+		dd of=/dev/$devname if=/dev/zero bs=10M count=1 oflag=direct status=none
+
+		end_time=$(date +%s.%N)
+		elapsed=$(echo "$end_time - $start_time" | bc)
+		printf "%.0f\n" "$elapsed"
+	} &
+
+	pid=$!
+	echo $! > $TEST_DIR/cgroup.procs
+
+	sleep 1
+	echo 0 > /sys/kernel/config/nullb/$devname/power
+	wait $pid
+}
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	if ! set_up_test; then
+		return 1;
+	fi
+
+	test_io
+
+	clean_up_test
+	echo "Test complete"
+}
diff --git a/tests/throtl/004.out b/tests/throtl/004.out
new file mode 100644
index 0000000..03331fe
--- /dev/null
+++ b/tests/throtl/004.out
@@ -0,0 +1,4 @@
+Running throtl/004
+dd: error writing '/dev/nullb0': Input/output error
+1
+Test complete
-- 
2.39.2