linux-kernel - [PATCH 3/4][Trivial] lib/kobject.c : Check ktype in kobject_add

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:	Sat, 21 Apr 2012 17:58:31 +0800
From:	yan <clouds.yan@...il.com>
To:	greg <gregkh@...uxfoundation.org>
Cc:	kernel <linux-kernel@...r.kernel.org>,
	message <message.get@...il.com>
Subject: [PATCH 3/4][Trivial] lib/kobject.c : Check ktype in
 kobject_add_internal

If someone calls kobject_init with null kobj_type, kobject_init can 
detect it. But it does not have a return value, it just dumps stack.
In this case, a kobject_add after that will result in:
   -->kobject_add_varg
    -->kobject_add_internal
     -->create_dir
      -->sysfs_create_dir
       -->sysfs_read_ns_type
        -->kobj_child_ns_ops
In the end, it will call ->ktype->child_ns_type directly and we have
an oops.

Check ktype before really add a kobject.

Signed-off-by: Yan Hong <clouds.yan@...il.com>
---
 lib/kobject.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/lib/kobject.c b/lib/kobject.c
index 85d5e9b..3ba6216 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -164,6 +164,9 @@ static int kobject_add_internal(struct kobject *kobj)
 	if (!kobj)
 		return -ENOENT;
 
+	if (!kobj->ktype)
+		return -EINVAL;
+
 	if (!kobj->name || !kobj->name[0]) {
 		WARN(1, "kobject: (%p): attempted to be registered with empty "
 			 "name!\n", kobj);
-- 
1.7.5.1







--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/