From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Mark Salyzyn <salyzyn@android.com>,
linux-security-module@vger.kernel.org, kernel-team@android.com,
Miklos Szeredi <mszeredi@redhat.com>
Subject: [PATCH 4.9 115/129] ovl: filter of trusted xattr results in audit
Date: Thu, 3 Oct 2019 17:53:58 +0200 [thread overview]
Message-ID: <20191003154411.608470733@linuxfoundation.org> (raw)
In-Reply-To: <20191003154318.081116689@linuxfoundation.org>
From: Mark Salyzyn <salyzyn@android.com>
commit 5c2e9f346b815841f9bed6029ebcb06415caf640 upstream.
When filtering xattr list for reading, presence of trusted xattr
results in a security audit log. However, if there is other content
no errno will be set, and if there isn't, the errno will be -ENODATA
and not -EPERM as is usually associated with a lack of capability.
The check does not block the request to list the xattrs present.
Switch to ns_capable_noaudit to reflect a more appropriate check.
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: linux-security-module@vger.kernel.org
Cc: kernel-team@android.com
Cc: stable@vger.kernel.org # v3.18+
Fixes: a082c6f680da ("ovl: filter trusted xattr for non-admin")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/overlayfs/inode.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -234,7 +234,8 @@ static bool ovl_can_list(const char *s)
return true;
/* Never list trusted.overlay, list other trusted for superuser only */
- return !ovl_is_private_xattr(s) && capable(CAP_SYS_ADMIN);
+ return !ovl_is_private_xattr(s) &&
+ ns_capable_noaudit(&init_user_ns, CAP_SYS_ADMIN);
}
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
parent reply other threads:[~2019-10-03 17:35 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <20191003154318.081116689@linuxfoundation.org>]
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