linux-ext4 - [PATCH 1/3] fs/ext4: release kobject/kset even when init/register fail

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]

Date:   Tue, 28 Nov 2017 00:17:59 +0100
From:   Riccardo Schirone <sirmy15@...il.com>
To:     tytso@....edu, adilger.kernel@...ger.ca, linux-ext4@...r.kernel.org
Cc:     Riccardo Schirone <sirmy15@...il.com>
Subject: [PATCH 1/3] fs/ext4: release kobject/kset even when init/register fail

Even when kobject_init_and_add/kset_register fail, the kobject has been
already initialized and the refcount set to 1. Thus it is necessary to
release the kobject/kset, to avoid the memory associated with it hanging
around forever.

Signed-off-by: Riccardo Schirone <sirmy15@...il.com>
---
 fs/ext4/sysfs.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 48c7a7d55ed3..b096e157934f 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -395,8 +395,11 @@ int ext4_register_sysfs(struct super_block *sb)
 	init_completion(&sbi->s_kobj_unregister);
 	err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
 				   "%s", sb->s_id);
-	if (err)
+	if (err) {
+		kobject_put(&sbi->s_kobj);
+		wait_for_completion(&sbi->s_kobj_unregister);
 		return err;
+	}
 
 	if (ext4_proc_root)
 		sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
@@ -429,15 +432,19 @@ int __init ext4_init_sysfs(void)
 	kobject_set_name(&ext4_kset.kobj, "ext4");
 	ext4_kset.kobj.parent = fs_kobj;
 	ret = kset_register(&ext4_kset);
-	if (ret)
+	if (ret) {
+		kset_unregister(&ext4_kset);
 		return ret;
+	}
 
 	ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype,
 				   NULL, "features");
-	if (ret)
+	if (ret) {
+		kobject_put(&ext4_feat);
 		kset_unregister(&ext4_kset);
-	else
+	} else {
 		ext4_proc_root = proc_mkdir(proc_dirname, NULL);
+	}
 	return ret;
 }
 
-- 
2.14.3