[PATCH] knfsd: fix up some bit-rot in exp_export

The nfsservctl systemcall isn't used but recent nfs-utils releases for
exporting filesystems, and consequently the code that is uses -
exp_export - has suffered some bitrot.

Particular:
  - some newly added fields in 'struct svc_export' are being initialised
    properly.
  - the return value is now always -ENOMEM ...

This patch fixes both these problems.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

fs/nfsd/export.c

@@ -950,6 +950,8 @@ exp_export(struct nfsctl_export *nxp)
 
 	exp = exp_get_by_name(clp, nd.mnt, nd.dentry, NULL);
 
+	memset(&new, 0, sizeof(new));
+
 	/* must make sure there won't be an ex_fsid clash */
 	if ((nxp->ex_flags & NFSEXP_FSID) &&
 	    (fsid_key = exp_get_fsid_key(clp, nxp->ex_dev)) &&
@@ -980,6 +982,9 @@ exp_export(struct nfsctl_export *nxp)
 
 	new.h.expiry_time = NEVER;
 	new.h.flags = 0;
+	new.ex_path = kstrdup(nxp->ex_path, GFP_KERNEL);
+	if (!new.ex_path)
+		goto finish;
 	new.ex_client = clp;
 	new.ex_mnt = nd.mnt;
 	new.ex_dentry = nd.dentry;
@@ -1000,10 +1005,11 @@ exp_export(struct nfsctl_export *nxp)
 		/* failed to create at least one index */
 		exp_do_unexport(exp);
 		cache_flush();
-		err = -ENOMEM;
-	}
-
+	} else
+		err = 0;
 finish:
+	if (new.ex_path)
+		kfree(new.ex_path);
 	if (exp)
 		exp_put(exp);
 	if (fsid_key && !IS_ERR(fsid_key))