userns: Convert group_info values from gid_t to kgid_t.

As a first step to converting struct cred to be all kuid_t and kgid_t
values convert the group values stored in group_info to always be
kgid_t values.   Unless user namespaces are used this change should
have no effect.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 1600cfb1618c..28b62dbb6d1e 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -41,6 +41,7 @@
 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/pagemap.h>
+#include <linux/user_namespace.h>
 
 #include <linux/sunrpc/auth_gss.h>
 #include <linux/sunrpc/gss_err.h>
@@ -470,9 +471,13 @@ static int rsc_parse(struct cache_detail *cd,
                 status = -EINVAL;
                 for (i=0; i<N; i++) {
                         gid_t gid;
+                        kgid_t kgid;
                         if (get_int(&mesg, &gid))
                                 goto out;
-                        GROUP_AT(rsci.cred.cr_group_info, i) = gid;
+                        kgid = make_kgid(&init_user_ns, gid);
+                        if (!gid_valid(kgid))
+                                goto out;
+                        GROUP_AT(rsci.cred.cr_group_info, i) = kgid;
                 }
 
                 /* mech name */