SUNRPC: Fix machine creds in generic_create_cred and generic_match

- generic_create_cred needs to copy the '.principal' field.
- generic_match needs to ignore the groups and match on the '.principal'
  field.

This fixes an Oops that was introduced by commit 68c9715 (SUNRPC:
Clean up the RPCSEC_GSS service ticket requests)

Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 16 insertions, 1 deletions

diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c
index 1426ec3d0a53..75762f346975 100644
--- a/net/sunrpc/auth_generic.c
+++ b/net/sunrpc/auth_generic.c
@@ -92,6 +92,7 @@ generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
         if (gcred->acred.group_info != NULL)
                 get_group_info(gcred->acred.group_info);
         gcred->acred.machine_cred = acred->machine_cred;
+        gcred->acred.principal = acred->principal;
 
         dprintk("RPC:       allocated %s cred %p for uid %d gid %d\n",
                         gcred->acred.machine_cred ? "machine" : "generic",
@@ -123,6 +124,17 @@ generic_destroy_cred(struct rpc_cred *cred)
         call_rcu(&cred->cr_rcu, generic_free_cred_callback);
 }
 
+static int
+machine_cred_match(struct auth_cred *acred, struct generic_cred *gcred, int flags)
+{
+        if (!gcred->acred.machine_cred ||
+            gcred->acred.principal != acred->principal ||
+            gcred->acred.uid != acred->uid ||
+            gcred->acred.gid != acred->gid)
+                return 0;
+        return 1;
+}
+
 /*
  * Match credentials against current process creds.
  */
@@ -132,9 +144,12 @@ generic_match(struct auth_cred *acred, struct rpc_cred *cred, int flags)
         struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
         int i;
 
+        if (acred->machine_cred)
+                return machine_cred_match(acred, gcred, flags);
+
         if (gcred->acred.uid != acred->uid ||
             gcred->acred.gid != acred->gid ||
-            gcred->acred.machine_cred != acred->machine_cred)
+            gcred->acred.machine_cred != 0)
                 goto out_nomatch;
 
         /* Optimisation in the case where pointers are identical... */