releases/4.4.120/xfs-quota-check-result-of-register_shrinker.patch

   1 From foo@baz Wed Feb 28 16:19:30 CET 2018
   2 From: Aliaksei Karaliou <akaraliou.dev@gmail.com>
   3 Date: Thu, 21 Dec 2017 13:18:26 -0800
   4 Subject: xfs: quota: check result of register_shrinker()
   5
   6 From: Aliaksei Karaliou <akaraliou.dev@gmail.com>
   7
   8
   9 [ Upstream commit 3a3882ff26fbdbaf5f7e13f6a0bccfbf7121041d ]
  10
  11 xfs_qm_init_quotainfo() does not check result of register_shrinker()
  12 which was tagged as __must_check recently, reported by sparse.
  13
  14 Signed-off-by: Aliaksei Karaliou <akaraliou.dev@gmail.com>
  15 [darrick: move xfs_qm_destroy_quotainos nearer xfs_qm_init_quotainos]
  16 Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
  17 Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
  18
  19 Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21 ---
  22  fs/xfs/xfs_qm.c |   45 +++++++++++++++++++++++++++++----------------
  23  1 file changed, 29 insertions(+), 16 deletions(-)
  24
  25 --- a/fs/xfs/xfs_qm.c
  26 +++ b/fs/xfs/xfs_qm.c
  27 @@ -47,7 +47,7 @@
  28  STATIC int     xfs_qm_init_quotainos(xfs_mount_t *);
  29  STATIC int     xfs_qm_init_quotainfo(xfs_mount_t *);
  30
  31 -
  32 +STATIC void    xfs_qm_destroy_quotainos(xfs_quotainfo_t *qi);
  33  STATIC void    xfs_qm_dqfree_one(struct xfs_dquot *dqp);
  34  /*
  35   * We use the batch lookup interface to iterate over the dquots as it
  36 @@ -660,9 +660,17 @@ xfs_qm_init_quotainfo(
  37         qinf->qi_shrinker.scan_objects = xfs_qm_shrink_scan;
  38         qinf->qi_shrinker.seeks = DEFAULT_SEEKS;
  39         qinf->qi_shrinker.flags = SHRINKER_NUMA_AWARE;
  40 -       register_shrinker(&qinf->qi_shrinker);
  41 +
  42 +       error = register_shrinker(&qinf->qi_shrinker);
  43 +       if (error)
  44 +               goto out_free_inos;
  45 +
  46         return 0;
  47
  48 +out_free_inos:
  49 +       mutex_destroy(&qinf->qi_quotaofflock);
  50 +       mutex_destroy(&qinf->qi_tree_lock);
  51 +       xfs_qm_destroy_quotainos(qinf);
  52  out_free_lru:
  53         list_lru_destroy(&qinf->qi_lru);
  54  out_free_qinf:
  55 @@ -671,7 +679,6 @@ out_free_qinf:
  56         return error;
  57  }
  58
  59 -
  60  /*
  61   * Gets called when unmounting a filesystem or when all quotas get
  62   * turned off.
  63 @@ -688,19 +695,7 @@ xfs_qm_destroy_quotainfo(
  64
  65         unregister_shrinker(&qi->qi_shrinker);
  66         list_lru_destroy(&qi->qi_lru);
  67 -
  68 -       if (qi->qi_uquotaip) {
  69 -               IRELE(qi->qi_uquotaip);
  70 -               qi->qi_uquotaip = NULL; /* paranoia */
  71 -       }
  72 -       if (qi->qi_gquotaip) {
  73 -               IRELE(qi->qi_gquotaip);
  74 -               qi->qi_gquotaip = NULL;
  75 -       }
  76 -       if (qi->qi_pquotaip) {
  77 -               IRELE(qi->qi_pquotaip);
  78 -               qi->qi_pquotaip = NULL;
  79 -       }
  80 +       xfs_qm_destroy_quotainos(qi);
  81         mutex_destroy(&qi->qi_tree_lock);
  82         mutex_destroy(&qi->qi_quotaofflock);
  83         kmem_free(qi);
  84 @@ -1563,6 +1558,24 @@ error_rele:
  85  }
  86
  87  STATIC void
  88 +xfs_qm_destroy_quotainos(
  89 +       xfs_quotainfo_t *qi)
  90 +{
  91 +       if (qi->qi_uquotaip) {
  92 +               IRELE(qi->qi_uquotaip);
  93 +               qi->qi_uquotaip = NULL; /* paranoia */
  94 +       }
  95 +       if (qi->qi_gquotaip) {
  96 +               IRELE(qi->qi_gquotaip);
  97 +               qi->qi_gquotaip = NULL;
  98 +       }
  99 +       if (qi->qi_pquotaip) {
 100 +               IRELE(qi->qi_pquotaip);
 101 +               qi->qi_pquotaip = NULL;
 102 +       }
 103 +}
 104 +
 105 +STATIC void
 106  xfs_qm_dqfree_one(
 107         struct xfs_dquot        *dqp)
 108  {