linux-kernel - [PATCH 4.19 234/276] rcuperf: Fix cleanup path for invalid perf

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190530030539.764604914@linuxfoundation.org>
Date:   Wed, 29 May 2019 20:06:32 -0700
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, "Paul E. McKenney" <paulmck@...ux.ibm.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.19 234/276] rcuperf: Fix cleanup path for invalid perf_type strings

[ Upstream commit ad092c027713a68a34168942a5ef422e42e039f4 ]

If the specified rcuperf.perf_type is not in the rcu_perf_init()
function's perf_ops[] array, rcuperf prints some console messages and
then invokes rcu_perf_cleanup() to set state so that a future torture
test can run.  However, rcu_perf_cleanup() also attempts to end the
test that didn't actually start, and in doing so relies on the value
of cur_ops, a value that is not particularly relevant in this case.
This can result in confusing output or even follow-on failures due to
attempts to use facilities that have not been properly initialized.

This commit therefore sets the value of cur_ops to NULL in this case and
inserts a check near the beginning of rcu_perf_cleanup(), thus avoiding
relying on an irrelevant cur_ops value.

Signed-off-by: Paul E. McKenney <paulmck@...ux.ibm.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 kernel/rcu/rcuperf.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index 34244523550e1..19249b86fb33e 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -561,6 +561,10 @@ rcu_perf_cleanup(void)

 	if (torture_cleanup_begin())
 		return;
+	if (!cur_ops) {
+		torture_cleanup_end();
+		return;
+	}

 	if (reader_tasks) {
 		for (i = 0; i < nrealreaders; i++)
@@ -681,6 +685,7 @@ rcu_perf_init(void)
 			pr_cont(" %s", perf_ops[i]->name);
 		pr_cont("\n");
 		firsterr = -EINVAL;
+		cur_ops = NULL;
 		goto unwind;
 	}
 	if (cur_ops->init)
-- 
2.20.1