Merge tag 'xfs-5.13-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "This week's pile mitigates some decades-old problems in how extent
  size hints interact with realtime volumes, fixes some failures in
  online shrink, and fixes a problem where directory and symlink
  shrinking on extremely fragmented filesystems could fail.

  The most user-notable change here is to point users at our (new) IRC
  channel on OFTC. Freedom isn't free, it costs folks like you and me;
  and if you don't kowtow, they'll expel everyone and take over your
  channel. (Ok, ok, that didn't fit the song lyrics...)

  Summary:

   - Fix a bug where unmapping operations end earlier than expected,
     which can cause chaos on multi-block directory and symlink shrink
     operations.

   - Fix an erroneous assert that can trigger if we try to transition a
     bmap structure from btree format to extents format with zero
     extents. This was exposed by xfs/538"

* tag 'xfs-5.13-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: bunmapi has unnecessary AG lock ordering issues
  xfs: btree format inode forks can have zero extents
  xfs: add new IRC channel to MAINTAINERS
  xfs: validate extsz hints against rt extent size when rtinherit is set
  xfs: standardize extent size hint validation
  xfs: check free AG space when making per-AG reservations

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 0369eb22c1bb..e4c2da4566f1 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -690,6 +690,7 @@ xfs_inode_inherit_flags(
 	const struct xfs_inode	*pip)
 {
 	unsigned int		di_flags = 0;
+	xfs_failaddr_t		failaddr;
 	umode_t			mode = VFS_I(ip)->i_mode;
 
 	if (S_ISDIR(mode)) {
@@ -729,6 +730,24 @@ xfs_inode_inherit_flags(
 		di_flags |= XFS_DIFLAG_FILESTREAM;
 
 	ip->i_diflags |= di_flags;
+
+	/*
+	 * Inode verifiers on older kernels only check that the extent size
+	 * hint is an integer multiple of the rt extent size on realtime files.
+	 * They did not check the hint alignment on a directory with both
+	 * rtinherit and extszinherit flags set.  If the misaligned hint is
+	 * propagated from a directory into a new realtime file, new file
+	 * allocations will fail due to math errors in the rt allocator and/or
+	 * trip the verifiers.  Validate the hint settings in the new file so
+	 * that we don't let broken hints propagate.
+	 */
+	failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
+			VFS_I(ip)->i_mode, ip->i_diflags);
+	if (failaddr) {
+		ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
+				   XFS_DIFLAG_EXTSZINHERIT);
+		ip->i_extsize = 0;
+	}
 }
 
 /* Propagate di_flags2 from a parent inode to a child inode. */
@@ -737,12 +756,22 @@ xfs_inode_inherit_flags2(
 	struct xfs_inode	*ip,
 	const struct xfs_inode	*pip)
 {
+	xfs_failaddr_t		failaddr;
+
 	if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
 		ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
 		ip->i_cowextsize = pip->i_cowextsize;
 	}
 	if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
 		ip->i_diflags2 |= XFS_DIFLAG2_DAX;
+
+	/* Don't let invalid cowextsize hints propagate. */
+	failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
+			VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
+	if (failaddr) {
+		ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
+		ip->i_cowextsize = 0;
+	}
 }
 
 /*