Don't count '@' for dataset namelen if not a snapshot

Don't count '@' for dataset namelen if not a snapshot. This fixes making a pool unimportable when the dataset namelen is 255. Add test file for zfs create name length 255. Reviewed-by: Giuseppe Di Natale <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Chunwei Chen <[email protected]> Closes #5432 Closes #5456
openzfs · Feb 3, 2017 · f3da7a1 · f3da7a1
1 parent 625ee0a
commit f3da7a1
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/module/zfs/dsl_dataset.c b/module/zfs/dsl_dataset.c
@@ -671,7 +671,11 @@ dsl_dataset_namelen(dsl_dataset_t *ds)
 	int len;
 	VERIFY0(dsl_dataset_get_snapname(ds));
 	mutex_enter(&ds->ds_lock);
-	len = dsl_dir_namelen(ds->ds_dir) + 1 + strlen(ds->ds_snapname);
+	len = strlen(ds->ds_snapname);
+	/* add '@' if ds is a snap */
+	if (len > 0)
+		len++;
+	len += dsl_dir_namelen(ds->ds_dir);
 	mutex_exit(&ds->ds_lock);
 	return (len);
 }