[PATCH 3.17 140/141] KEYS: Reinstate EPERM for a key type name beginning with a .

Greg Kroah-Hartman
2014-11-19T22:10:46Z

From: David Howells <dhowells@redhat.com>

commit 54e2c2c1a9d6cbb270b0999a38545fa9a69bee43 upstream.

Reinstate the generation of EPERM for a key type name beginning with a '.' in
a userspace call. Types whose name begins with a '.' are internal only.

The test was removed by:

commit a4e3b8d79a5c6d40f4a9703abf7fe3abcc6c3b8d
Author: Mimi Zohar <zohar@linux.vnet.ibm.com>
Date: Thu May 22 14:02:23 2014 -0400
Subject: KEYS: special dot prefixed keyring name bug fix

I think we want to keep the restriction on type name so that userspace can't
add keys of a special internal type.

Note that removal of the test causes several of the tests in the keyutils
testsuite to fail.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
security/keys/keyctl.c | 2 ++
1 file changed, 2 insertions(+)

--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -37,6 +37,8 @@ static int key_get_type_from_user(char *
return ret;
if (ret == 0 || ret >= len)
return -EINVAL;
+ if (type[0] == '.')
+ return -EPERM;
type[len - 1] = '\0';
return 0;
}