Merge tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "A few fixes for issues in the new online shrink code, additional
  corrections for my recent bug-hunt w.r.t. extent size hints on
  realtime, and improved input checking of the GROWFSRT ioctl.

  IOW, the usual 'I somehow got bored during the merge window and
  resumed auditing the farther reaches of xfs':

   - Fix shrink eligibility checking when sparse inode clusters enabled

   - Reset '..' directory entries when unlinking directories to prevent
     verifier errors if fs is shrinked later

   - Don't report unusable extent size hints to FSGETXATTR

   - Don't warn when extent size hints are unusable because the sysadmin
     configured them that way

   - Fix insufficient parameter validation in GROWFSRT ioctl

   - Fix integer overflow when adding rt volumes to filesystem"

* tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: detect misaligned rtinherit directory extent size hints
  xfs: fix an integer overflow error in xfs_growfs_rt
  xfs: improve FSGROWFSRT precondition checking
  xfs: don't expose misaligned extszinherit hints to userspace
  xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
  xfs: reset child dir '..' entry when unlinking child
  xfs: check for sparse inode clusters that cross new EOAG when shrinking

1 files changed, 55 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 57d9cb632983..aaf8805a82df 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -2928,3 +2928,58 @@ xfs_ialloc_calc_rootino(
 
 	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
 }
+
+/*
+ * Ensure there are not sparse inode clusters that cross the new EOAG.
+ *
+ * This is a no-op for non-spinode filesystems since clusters are always fully
+ * allocated and checking the bnobt suffices.  However, a spinode filesystem
+ * could have a record where the upper inodes are free blocks.  If those blocks
+ * were removed from the filesystem, the inode record would extend beyond EOAG,
+ * which will be flagged as corruption.
+ */
+int
+xfs_ialloc_check_shrink(
+	struct xfs_trans	*tp,
+	xfs_agnumber_t		agno,
+	struct xfs_buf		*agibp,
+	xfs_agblock_t		new_length)
+{
+	struct xfs_inobt_rec_incore rec;
+	struct xfs_btree_cur	*cur;
+	struct xfs_mount	*mp = tp->t_mountp;
+	struct xfs_perag	*pag;
+	xfs_agino_t		agino = XFS_AGB_TO_AGINO(mp, new_length);
+	int			has;
+	int			error;
+
+	if (!xfs_sb_version_hassparseinodes(&mp->m_sb))
+		return 0;
+
+	pag = xfs_perag_get(mp, agno);
+	cur = xfs_inobt_init_cursor(mp, tp, agibp, pag, XFS_BTNUM_INO);
+
+	/* Look up the inobt record that would correspond to the new EOFS. */
+	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
+	if (error || !has)
+		goto out;
+
+	error = xfs_inobt_get_rec(cur, &rec, &has);
+	if (error)
+		goto out;
+
+	if (!has) {
+		error = -EFSCORRUPTED;
+		goto out;
+	}
+
+	/* If the record covers inodes that would be beyond EOFS, bail out. */
+	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
+		error = -ENOSPC;
+		goto out;
+	}
+out:
+	xfs_btree_del_cursor(cur, error);
+	xfs_perag_put(pag);
+	return error;
+}