Re: [PATCH 01/16] xfs_repair: fix missing dir buffer corruption checks

Darrick J. Wong
2020-05-11T16:46:31Z

On Sat, May 09, 2020 at 10:08:50AM -0700, Christoph Hellwig wrote:
> On Sat, May 09, 2020 at 09:29:58AM -0700, Darrick J. Wong wrote:
> > @@ -140,11 +140,24 @@ _("can't read %s block %u for inode %" PRIu64 "\n"),
> > if (whichfork == XFS_DATA_FORK &&
> > (nodehdr.magic == XFS_DIR2_LEAFN_MAGIC ||
> > nodehdr.magic == XFS_DIR3_LEAFN_MAGIC)) {
> > + int bad = 0;
> > +
> > if (i != -1) {
> > do_warn(
> > _("found non-root LEAFN node in inode %" PRIu64 " bno = %u\n"),
> > da_cursor->ino, bno);
> > + bad++;
> > }
> > +
> > + /* corrupt leafn node; rebuild the dir. */
> > + if (!bad &&
> > + (bp->b_error == -EFSBADCRC ||
> > + bp->b_error == -EFSCORRUPTED)) {
> > + do_warn(
> > +_("corrupt %s LEAFN block %u for inode %" PRIu64 "\n"),
> > + FORKNAME(whichfork), bno, da_cursor->ino);
> > + }
> > +
>
> So this doesn't really change any return value, but just the error
> message. But looking at this code I wonder why we don't check
> b_error first thing after reading the buffer, as checking the magic
> for a corrupt buffer seems a little pointless.

<shrug> In the first hunk I was merely following what we did for DA_NODE
blocks (check magic, then check for corruption errors) but I guess I
could just pull that up in the file. I'll have a look and see what
happens if I do that.

--D