linux-kernel - [PATCH] sched,debug: fix dentry leak in update_sched_domain

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-next>] [day] [month] [year] [list]

Date:   Mon, 11 Jul 2022 11:03:41 +0800
From:   Major Chen <major.chen@...sung.com>
To:     "mingo@...hat.com" <mingo@...hat.com>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "juri.lelli@...hat.com" <juri.lelli@...hat.com>,
        "vincent.guittot@...aro.org" <vincent.guittot@...aro.org>,
        "dietmar.eggemann@....com" <dietmar.eggemann@....com>,
        "rostedt@...dmis.org" <rostedt@...dmis.org>,
        "bsegall@...gle.com" <bsegall@...gle.com>,
        "mgorman@...e.de" <mgorman@...e.de>,
        "bristot@...hat.com" <bristot@...hat.com>
CC:     Hongfei Tang <hongfei.tang@...sung.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: [PATCH] sched,debug: fix dentry leak in update_sched_domain_debugfs

 
update_sched_domain_debugfs() uses debugfs_lookup() to find wanted dentry(which has
been created by debugfs_create_dir() before), but not call dput() to return this dentry
back. This result in dentry leak even debugfs_remove() is called.
 
Signed-off-by: major.chen <major.chen@...sung.com>
---
 kernel/sched/debug.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
 
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index bb3d63b..4ffea2d 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -412,11 +412,14 @@ void update_sched_domain_debugfs(void)
 
         for_each_cpu(cpu, sd_sysctl_cpus) {
                 struct sched_domain *sd;
-                struct dentry *d_cpu;
+                struct dentry *d_cpu, *d_lookup;
                 char buf[32];
 
                 snprintf(buf, sizeof(buf), "cpu%d", cpu);
-                debugfs_remove(debugfs_lookup(buf, sd_dentry));
+                d_lookup = debugfs_lookup(buf, sd_dentry);
+                debugfs_remove(d_lookup);
+                if (!IS_ERR_OR_NULL(d_lookup))
+                        dput(d_lookup);
                 d_cpu = debugfs_create_dir(buf, sd_dentry);
 
                 i = 0;
-- 
2.7.4