Pull xfs fixes from Darrick Wong:
 "Nothing exciting, just more fixes for not returning sync_filesystem
  error values (and eliding it when it's not necessary).

  Summary:

   - Only call sync_filesystem when we're remounting the filesystem
     readonly readonly, and actually check its return value"

* tag 'xfs-5.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: only bother with sync_filesystem during readonly remount

In commit 02b9984d6408, we pushed a sync_filesystem() call from the VFS
into xfs_fs_remount.  The only time that we ever need to push dirty file
data or metadata to disk for a remount is if we're remounting the
filesystem read only, so this really could be moved to xfs_remount_ro.

Once we've moved the call site, actually check the return value from
sync_filesystem.

Fixes: 02b9984d6408 ("fs: push sync_filesystem() down to the file system's remount_fs()")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

Pull xfs fixes from Darrick Wong:
 "I was auditing operations in XFS that clear file privileges, and
  realized that XFS' fallocate implementation drops suid/sgid but
  doesn't clear file capabilities the same way that file writes and
  reflink do.

  There are VFS helpers that do it correctly, so refactor XFS to use
  them. I also noticed that we weren't flushing the log at the correct
  point in the fallocate operation, so that's fixed too.

  Summary:

   - Fix fallocate so that it drops all file privileges when files are
     modified instead of open-coding that incompletely.

   - Fix fallocate to flush the log if the caller wanted synchronous
     file updates"

* tag 'xfs-5.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: ensure log flush at the end of a synchronous fallocate call
  xfs: move xfs_update_prealloc_flags() to xfs_pnfs.c
  xfs: set prealloc flag in xfs_alloc_file_space()
  xfs: fallocate() should call file_modified()
  xfs: remove XFS_PREALLOC_SYNC
  xfs: reject crazy array sizes being fed to XFS_IOC_GETBMAP*

Pull vfs fixes from Darrick Wong:
 "I was auditing the sync_fs code paths recently and noticed that most
  callers of ->sync_fs ignore its return value (and many implementations
  never return nonzero even if the fs is broken!), which means that
  internal fs errors and corruption are not passed up to userspace
  callers of syncfs(2) or FIFREEZE. Hence fixing the common code and
  XFS, and I'll start working on the ext4/btrfs folks if this is merged.

  Summary:

   - Fix a bug where callers of ->sync_fs (e.g. sync_filesystem and
     syncfs(2)) ignore the return value.

   - Fix a bug where callers of sync_filesystem (e.g. fs freeze) ignore
     the return value.

   - Fix a bug in XFS where xfs_fs_sync_fs never passed back error
     returns"

* tag 'vfs-5.17-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: return errors in xfs_fs_sync_fs
  quota: make dquot_quota_sync return errors from ->sync_fs
  vfs: make sync_filesystem return errors from ->sync_fs
  vfs: make freeze_super abort when sync_filesystem returns error

Since we've started treating fallocate more like a file write, we
should flush the log to disk if the user has asked for synchronous
writes either by setting it via fcntl flags, or inode flags, or with
the sync mount option.  We've already got a helper for this, so use
it.

[The original patch by Darrick was massaged by Dave to fit this patchset]

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

The operations that xfs_update_prealloc_flags() perform are now
unique to xfs_fs_map_blocks(), so move xfs_update_prealloc_flags()
to be a static function in xfs_pnfs.c and cut out all the
other functionality that is doesn't use anymore.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Now that we only call xfs_update_prealloc_flags() from
xfs_file_fallocate() in the case where we need to set the
preallocation flag, do this in xfs_alloc_file_space() where we
already have the inode joined into a transaction and get
rid of the call to xfs_update_prealloc_flags() from the fallocate
code.

This also means that we now correctly avoid setting the
XFS_DIFLAG_PREALLOC flag when xfs_is_always_cow_inode() is true, as
these inodes will never have preallocated extents.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

In XFS, we always update the inode change and modification time when
any fallocate() operation succeeds.  Furthermore, as various
fallocate modes can change the file contents (extending EOF,
punching holes, zeroing things, shifting extents), we should drop
file privileges like suid just like we do for a regular write().
There's already a VFS helper that figures all this out for us, so
use that.

The net effect of this is that we no longer drop suid/sgid if the
caller is root, but we also now drop file capabilities.

We also move the xfs_update_prealloc_flags() function so that it now
is only called by the scope that needs to set the the prealloc flag.

Based on a patch from Darrick Wong.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Callers can acheive the same thing by calling xfs_log_force_inode()
after making their modifications. There is no need for
xfs_update_prealloc_flags() to do this.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

Syzbot tripped over the following complaint from the kernel:

WARNING: CPU: 2 PID: 15402 at mm/util.c:597 kvmalloc_node+0x11e/0x125 mm/util.c:597

While trying to run XFS_IOC_GETBMAP against the following structure:

struct getbmap fubar = {
	.bmv_count	= 0x22dae649,
};

Obviously, this is a crazy huge value since the next thing that the
ioctl would do is allocate 37GB of memory.  This is enough to make
kvmalloc mad, but isn't large enough to trip the validation functions.
In other words, I'm fussing with checks that were **already sufficient**
because that's easier than dealing with 644 internal bug reports.  Yes,
that's right, six hundred and forty-four.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Catherine Hoang <catherine.hoang@oracle.com>