On Fri 10-04-20 00:33:21, Theodore Y. Ts'o wrote:
> On Tue, Mar 31, 2020 at 04:30:35PM +0200, Jan Kara wrote:
> > > > > Don't we have basically the same off-by-one in
> > > > > e2fsck/pass1.c handle_htree() ?
> > > > >
> > > > > if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
> > > > > fix_problem(ctx, PR_1_HTREE_DEPTH, pctx))
> > > >
> > >
> > > root->indirect_levels is zero based, while ext2_dir_htree_level()
> > > returns the maximum number of levels (that is 3 by default). If I am
> > > right then indirect_levels must always be smaller then
> > > ext2_dir_htree_level() and that is how we use it everywhere else - the
> > > palce I am pointing out is an exception and I think it's a bug.
> > >
> > > Indeed it looks like the bug got introduced in
> > > 3f0cf647539970474be8f607017ca7eccfc2fbbe
> > >
> > > - if ((root->indirect_levels > 1) &&
> > > + if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
> > >
> > > Or am I missing something ?
> >
> > Ah, you're indeed right! e2fsck/pass2.c even has a correct version of the
> > condition. Just the condition in pass1.c is wrong.
>
> I've applied the following fix on the maint branch.
>
> - Ted
>
> commit 759b387775bfd5c9d3692680e5e4b929c3848d51
> Author: Theodore Ts'o <tytso@xxxxxxx>
> Date: Fri Apr 10 00:30:52 2020 -0400
>
> e2fsck: fix off-by-one check when validating depth of an htree
>
> Fixes: 3f0cf6475399 ("e2fsprogs: add support for 3-level htree")
>
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cool, thanks! Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
>
> diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
> index c9e8bf82..38afda48 100644
> --- a/e2fsck/pass1.c
> +++ b/e2fsck/pass1.c
> @@ -2685,7 +2685,7 @@ static int handle_htree(e2fsck_t ctx, struct problem_context *pctx,
> return 1;
>
> pctx->num = root->indirect_levels;
> - if ((root->indirect_levels > ext2_dir_htree_level(fs)) &&
> + if ((root->indirect_levels >= ext2_dir_htree_level(fs)) &&
> fix_problem(ctx, PR_1_HTREE_DEPTH, pctx))
> return 1;
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
