release-kobject-kset-even-when-init-register-fail

   1 ext4: release kobject/kset even when init/register fail
   2
   3 From: Riccardo Schirone <sirmy15@gmail.com>
   4
   5 Even when kobject_init_and_add/kset_register fail, the kobject has been
   6 already initialized and the refcount set to 1. Thus it is necessary to
   7 release the kobject/kset, to avoid the memory associated with it hanging
   8 around forever.
   9
  10 Signed-off-by: Riccardo Schirone <sirmy15@gmail.com>
  11 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  12 ---
  13  fs/ext4/sysfs.c | 15 +++++++++++----
  14  1 file changed, 11 insertions(+), 4 deletions(-)
  15
  16 diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
  17 index 48c7a7d55ed3..b096e157934f 100644
  18 --- a/fs/ext4/sysfs.c
  19 +++ b/fs/ext4/sysfs.c
  20 @@ -395,8 +395,11 @@ int ext4_register_sysfs(struct super_block *sb)
  21         init_completion(&sbi->s_kobj_unregister);
  22         err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
  23                                    "%s", sb->s_id);
  24 -       if (err)
  25 +       if (err) {
  26 +               kobject_put(&sbi->s_kobj);
  27 +               wait_for_completion(&sbi->s_kobj_unregister);
  28                 return err;
  29 +       }
  30
  31         if (ext4_proc_root)
  32                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
  33 @@ -429,15 +432,19 @@ int __init ext4_init_sysfs(void)
  34         kobject_set_name(&ext4_kset.kobj, "ext4");
  35         ext4_kset.kobj.parent = fs_kobj;
  36         ret = kset_register(&ext4_kset);
  37 -       if (ret)
  38 +       if (ret) {
  39 +               kset_unregister(&ext4_kset);
  40                 return ret;
  41 +       }
  42
  43         ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype,
  44                                    NULL, "features");
  45 -       if (ret)
  46 +       if (ret) {
  47 +               kobject_put(&ext4_feat);
  48                 kset_unregister(&ext4_kset);
  49 -       else
  50 +       } else {
  51                 ext4_proc_root = proc_mkdir(proc_dirname, NULL);
  52 +       }
  53         return ret;
  54  }
  55
  56 --
  57 2.14.3
  58
  59