From: Seth Forshee <seth.forshee@canonical.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Casey Schaufler <casey@schaufler-ca.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>,
Andy Lutomirski <luto@amacapital.net>,
Seth Forshee <seth.forshee@canonical.com>,
linux-fsdevel@vger.kernel.org,
linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov,
linux-kernel@vger.kernel.org,
James Morris <james.l.morris@oracle.com>,
"Serge E. Hallyn" <serge@hallyn.com>
Subject: [PATCH 7/7] smack: Don't use security labels for user namespace mounts
Date: Wed, 15 Jul 2015 14:46:08 -0500 [thread overview]
Message-ID: <1436989569-69582-8-git-send-email-seth.forshee@canonical.com> (raw)
In-Reply-To: <1436989569-69582-1-git-send-email-seth.forshee@canonical.com>
Avoid use of untrusted security labels when s_user_ns !=
init_user_ns:
- smk_fetch: refuse to read labels from disk
- smack_inode_init_security: return -ENOTSUPP
- smack_d_instantiate: don't use security xattrs from disk
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
---
security/smack/smack_lsm.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index a143328f75eb..6a849da94f47 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -255,6 +255,9 @@ static struct smack_known *smk_fetch(const char *name, struct inode *ip,
char *buffer;
struct smack_known *skp = NULL;
+ if (ip->i_sb->s_user_ns != &init_user_ns)
+ return NULL;
+
if (ip->i_op->getxattr == NULL)
return ERR_PTR(-EOPNOTSUPP);
@@ -833,6 +836,9 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
struct smack_known *dsp = smk_of_inode(dir);
int may;
+ if (inode->i_sb->s_user_ns != &init_user_ns)
+ return -ENOTSUPP;
+
if (name)
*name = XATTR_SMACK_SUFFIX;
@@ -3176,11 +3182,13 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
}
/*
* No xattr support means, alas, no SMACK label.
- * Use the aforeapplied default.
+ * Use the aforeapplied default. Also don't use
+ * xattrs from userns mounts.
* It would be curious if the label of the task
* does not match that assigned.
*/
- if (inode->i_op->getxattr == NULL)
+ if (inode->i_sb->s_user_ns != &init_user_ns ||
+ inode->i_op->getxattr == NULL)
break;
/*
* Get the dentry for xattr.
--
1.9.1
WARNING: multiple messages have this Message-ID (diff)
From: Seth Forshee <seth.forshee@canonical.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Casey Schaufler <casey@schaufler-ca.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>,
James Morris <james.l.morris@oracle.com>,
linux-kernel@vger.kernel.org,
Andy Lutomirski <luto@amacapital.net>,
Seth Forshee <seth.forshee@canonical.com>,
linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov,
linux-fsdevel@vger.kernel.org
Subject: [PATCH 7/7] smack: Don't use security labels for user namespace mounts
Date: Wed, 15 Jul 2015 14:46:08 -0500 [thread overview]
Message-ID: <1436989569-69582-8-git-send-email-seth.forshee@canonical.com> (raw)
In-Reply-To: <1436989569-69582-1-git-send-email-seth.forshee@canonical.com>
Avoid use of untrusted security labels when s_user_ns !=
init_user_ns:
- smk_fetch: refuse to read labels from disk
- smack_inode_init_security: return -ENOTSUPP
- smack_d_instantiate: don't use security xattrs from disk
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
---
security/smack/smack_lsm.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index a143328f75eb..6a849da94f47 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -255,6 +255,9 @@ static struct smack_known *smk_fetch(const char *name, struct inode *ip,
char *buffer;
struct smack_known *skp = NULL;
+ if (ip->i_sb->s_user_ns != &init_user_ns)
+ return NULL;
+
if (ip->i_op->getxattr == NULL)
return ERR_PTR(-EOPNOTSUPP);
@@ -833,6 +836,9 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
struct smack_known *dsp = smk_of_inode(dir);
int may;
+ if (inode->i_sb->s_user_ns != &init_user_ns)
+ return -ENOTSUPP;
+
if (name)
*name = XATTR_SMACK_SUFFIX;
@@ -3176,11 +3182,13 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
}
/*
* No xattr support means, alas, no SMACK label.
- * Use the aforeapplied default.
+ * Use the aforeapplied default. Also don't use
+ * xattrs from userns mounts.
* It would be curious if the label of the task
* does not match that assigned.
*/
- if (inode->i_op->getxattr == NULL)
+ if (inode->i_sb->s_user_ns != &init_user_ns ||
+ inode->i_op->getxattr == NULL)
break;
/*
* Get the dentry for xattr.
--
1.9.1
next prev parent reply other threads:[~2015-07-15 19:47 UTC|newest]
Thread overview: 210+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-15 19:46 [PATCH 0/7] Initial support for user namespace owned mounts Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 1/7] fs: Add user namesapace member to struct super_block Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-16 2:47 ` Eric W. Biederman
2015-07-16 2:47 ` Eric W. Biederman
2015-08-05 21:03 ` Seth Forshee
2015-08-05 21:03 ` Seth Forshee
2015-08-05 21:19 ` Eric W. Biederman
2015-08-05 21:19 ` Eric W. Biederman
2015-08-06 14:20 ` Seth Forshee
2015-08-06 14:20 ` Seth Forshee
2015-08-06 14:51 ` Stephen Smalley
2015-08-06 14:51 ` Stephen Smalley
2015-08-06 15:44 ` Seth Forshee
2015-08-06 15:44 ` Seth Forshee
2015-08-06 16:11 ` Stephen Smalley
2015-08-06 16:11 ` Stephen Smalley
2015-08-07 14:16 ` Seth Forshee
2015-08-07 14:16 ` Seth Forshee
2015-08-07 14:32 ` Seth Forshee
2015-08-07 14:32 ` Seth Forshee
2015-08-07 18:35 ` Casey Schaufler
2015-08-07 18:35 ` Casey Schaufler
2015-08-07 18:57 ` Seth Forshee
2015-08-07 18:57 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 2/7] userns: Simpilify MNT_NODEV handling Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 3/7] fs: Ignore file caps in mounts from other user namespaces Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-15 21:48 ` Serge E. Hallyn
2015-07-15 21:48 ` Serge E. Hallyn
2015-07-15 21:50 ` Andy Lutomirski
2015-07-15 21:50 ` Andy Lutomirski
2015-07-15 22:35 ` Eric W. Biederman
2015-07-15 22:35 ` Eric W. Biederman
2015-07-16 1:14 ` Seth Forshee
2015-07-16 1:14 ` Seth Forshee
2015-07-16 1:23 ` Andy Lutomirski
2015-07-16 1:23 ` Andy Lutomirski
2015-07-16 13:06 ` Seth Forshee
2015-07-16 13:06 ` Seth Forshee
2015-07-16 1:19 ` Andy Lutomirski
2015-07-16 1:19 ` Andy Lutomirski
2015-07-16 4:23 ` Eric W. Biederman
2015-07-16 4:23 ` Eric W. Biederman
2015-07-16 4:49 ` Andy Lutomirski
2015-07-16 4:49 ` Andy Lutomirski
2015-07-16 5:04 ` Eric W. Biederman
2015-07-16 5:04 ` Eric W. Biederman
2015-07-16 5:15 ` Andy Lutomirski
2015-07-16 5:15 ` Andy Lutomirski
2015-07-16 5:44 ` Eric W. Biederman
2015-07-16 5:44 ` Eric W. Biederman
2015-07-16 13:13 ` Seth Forshee
2015-07-16 13:13 ` Seth Forshee
2015-07-17 0:43 ` Eric W. Biederman
2015-07-17 0:43 ` Eric W. Biederman
2015-07-29 16:04 ` Serge E. Hallyn
2015-07-29 16:04 ` Serge E. Hallyn
2015-07-29 16:18 ` Serge E. Hallyn
2015-07-29 16:18 ` Serge E. Hallyn
2015-07-15 19:46 ` [PATCH 4/7] fs: Treat foreign mounts as nosuid Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-17 6:46 ` Nikolay Borisov
2015-07-17 6:46 ` Nikolay Borisov
2015-07-15 19:46 ` [PATCH 5/7] security: Restrict security attribute updates for userns mounts Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 6/7] selinux: Ignore security labels on user namespace mounts Seth Forshee
2015-07-15 19:46 ` Seth Forshee
2015-07-16 13:23 ` Stephen Smalley
2015-07-22 16:02 ` Stephen Smalley
2015-07-22 16:14 ` Seth Forshee
2015-07-22 16:14 ` Seth Forshee
2015-07-22 20:25 ` Stephen Smalley
2015-07-22 20:25 ` Stephen Smalley
2015-07-22 20:40 ` Stephen Smalley
2015-07-22 20:40 ` Stephen Smalley
2015-07-23 13:57 ` Stephen Smalley
2015-07-23 13:57 ` Stephen Smalley
2015-07-23 14:39 ` Seth Forshee
2015-07-23 14:39 ` Seth Forshee
2015-07-23 15:36 ` Stephen Smalley
2015-07-23 15:36 ` Stephen Smalley
2015-07-23 16:23 ` Seth Forshee
2015-07-23 16:23 ` Seth Forshee
2015-07-24 15:11 ` Seth Forshee
2015-07-24 15:11 ` Seth Forshee
2015-07-30 15:57 ` Stephen Smalley
2015-07-30 15:57 ` Stephen Smalley
2015-07-30 16:24 ` Seth Forshee
2015-07-30 16:24 ` Seth Forshee
2015-07-15 19:46 ` Seth Forshee [this message]
2015-07-15 19:46 ` [PATCH 7/7] smack: Don't use security labels for " Seth Forshee
2015-07-15 20:43 ` Casey Schaufler
2015-07-15 20:43 ` Casey Schaufler
2015-07-15 20:36 ` [PATCH 0/7] Initial support for user namespace owned mounts Casey Schaufler
2015-07-15 20:36 ` Casey Schaufler
2015-07-15 21:06 ` Eric W. Biederman
2015-07-15 21:06 ` Eric W. Biederman
2015-07-15 21:48 ` Seth Forshee
2015-07-15 21:48 ` Seth Forshee
2015-07-15 22:28 ` Eric W. Biederman
2015-07-15 22:28 ` Eric W. Biederman
2015-07-16 1:05 ` Andy Lutomirski
2015-07-16 1:05 ` Andy Lutomirski
2015-07-16 2:20 ` Eric W. Biederman
2015-07-16 2:20 ` Eric W. Biederman
2015-07-16 13:12 ` Stephen Smalley
2015-07-16 13:12 ` Stephen Smalley
2015-07-15 23:04 ` Casey Schaufler
2015-07-15 23:04 ` Casey Schaufler
2015-07-15 22:39 ` Casey Schaufler
2015-07-15 22:39 ` Casey Schaufler
2015-07-16 1:08 ` Andy Lutomirski
2015-07-16 1:08 ` Andy Lutomirski
2015-07-16 2:54 ` Casey Schaufler
2015-07-16 2:54 ` Casey Schaufler
2015-07-16 4:47 ` Eric W. Biederman
2015-07-16 4:47 ` Eric W. Biederman
2015-07-17 0:09 ` Dave Chinner
2015-07-17 0:09 ` Dave Chinner
2015-07-17 0:42 ` Eric W. Biederman
2015-07-17 0:42 ` Eric W. Biederman
2015-07-17 2:47 ` Dave Chinner
2015-07-17 2:47 ` Dave Chinner
2015-07-21 17:37 ` J. Bruce Fields
2015-07-21 17:37 ` J. Bruce Fields
2015-07-22 7:56 ` Dave Chinner
2015-07-22 7:56 ` Dave Chinner
2015-07-22 14:09 ` J. Bruce Fields
2015-07-22 14:09 ` J. Bruce Fields
2015-07-22 16:52 ` Austin S Hemmelgarn
2015-07-22 16:52 ` Austin S Hemmelgarn
2015-07-22 17:41 ` J. Bruce Fields
2015-07-22 17:41 ` J. Bruce Fields
2015-07-23 1:51 ` Dave Chinner
2015-07-23 1:51 ` Dave Chinner
2015-07-23 13:19 ` J. Bruce Fields
2015-07-23 13:19 ` J. Bruce Fields
2015-07-23 23:48 ` Dave Chinner
2015-07-23 23:48 ` Dave Chinner
2015-07-18 0:07 ` Serge E. Hallyn
2015-07-18 0:07 ` Serge E. Hallyn
2015-07-20 17:54 ` Colin Walters
2015-07-20 17:54 ` Colin Walters
2015-07-16 11:16 ` Lukasz Pawelczyk
2015-07-16 11:16 ` Lukasz Pawelczyk
2015-07-17 0:10 ` Eric W. Biederman
2015-07-17 0:10 ` Eric W. Biederman
2015-07-17 10:13 ` Lukasz Pawelczyk
2015-07-17 10:13 ` Lukasz Pawelczyk
2015-07-16 3:15 ` Eric W. Biederman
2015-07-16 3:15 ` Eric W. Biederman
2015-07-16 13:59 ` Seth Forshee
2015-07-16 13:59 ` Seth Forshee
2015-07-16 15:09 ` Casey Schaufler
2015-07-16 15:09 ` Casey Schaufler
2015-07-16 18:57 ` Seth Forshee
2015-07-16 18:57 ` Seth Forshee
2015-07-16 21:42 ` Casey Schaufler
2015-07-16 21:42 ` Casey Schaufler
2015-07-16 22:27 ` Andy Lutomirski
2015-07-16 22:27 ` Andy Lutomirski
2015-07-16 23:08 ` Casey Schaufler
2015-07-16 23:08 ` Casey Schaufler
2015-07-16 23:29 ` Andy Lutomirski
2015-07-16 23:29 ` Andy Lutomirski
2015-07-17 0:45 ` Casey Schaufler
2015-07-17 0:45 ` Casey Schaufler
2015-07-17 0:59 ` Andy Lutomirski
2015-07-17 0:59 ` Andy Lutomirski
2015-07-17 14:28 ` Serge E. Hallyn
2015-07-17 14:28 ` Serge E. Hallyn
2015-07-17 14:56 ` Seth Forshee
2015-07-17 14:56 ` Seth Forshee
2015-07-21 20:35 ` Seth Forshee
2015-07-21 20:35 ` Seth Forshee
2015-07-22 1:52 ` Casey Schaufler
2015-07-22 1:52 ` Casey Schaufler
2015-07-22 15:56 ` Seth Forshee
2015-07-22 15:56 ` Seth Forshee
2015-07-22 18:10 ` Casey Schaufler
2015-07-22 18:10 ` Casey Schaufler
2015-07-22 19:32 ` Seth Forshee
2015-07-22 19:32 ` Seth Forshee
2015-07-23 0:05 ` Casey Schaufler
2015-07-23 0:05 ` Casey Schaufler
2015-07-23 0:15 ` Eric W. Biederman
2015-07-23 0:15 ` Eric W. Biederman
2015-07-23 5:15 ` Seth Forshee
2015-07-23 5:15 ` Seth Forshee
2015-07-23 21:48 ` Casey Schaufler
2015-07-23 21:48 ` Casey Schaufler
2015-07-28 20:40 ` Seth Forshee
2015-07-28 20:40 ` Seth Forshee
2015-07-30 16:18 ` Casey Schaufler
2015-07-30 16:18 ` Casey Schaufler
2015-07-30 17:05 ` Eric W. Biederman
2015-07-30 17:05 ` Eric W. Biederman
2015-07-30 17:25 ` Seth Forshee
2015-07-30 17:25 ` Seth Forshee
2015-07-30 17:33 ` Eric W. Biederman
2015-07-30 17:33 ` Eric W. Biederman
2015-07-17 13:21 ` Seth Forshee
2015-07-17 13:21 ` Seth Forshee
2015-07-17 17:14 ` Casey Schaufler
2015-07-17 17:14 ` Casey Schaufler
2015-07-16 15:59 ` Seth Forshee
2015-07-16 15:59 ` Seth Forshee
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