lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Thu, 24 Oct 2019 12:30:38 +0200
From:   Jan Kara <>
To:     "Theodore Y. Ts'o" <>
Cc:     Jan Kara <>,,
Subject: Re: [PATCH 04/22] ext4: Fix credit estimate for final inode freeing

On Sun 20-10-19 21:07:23, Theodore Y. Ts'o wrote:
> On Fri, Oct 04, 2019 at 12:05:50AM +0200, Jan Kara wrote:
> > Estimate for the number of credits needed for final freeing of inode in
> > ext4_evict_inode() was to small. We may modify 4 blocks (inode & sb for
> > orphan deletion, bitmap & group descriptor for inode freeing) and not
> > just 3.
> The modification for the inode should already be included in the
> calculation for ext4_blocks_for_truncate(), no?  So we only need 3
> extra blocks (sb, inode bitmap, and bg descriptor for the inode).

Yes, but 'extra_credits' is also passed to ext4_xattr_delete_inode() and if
that needs to restart a transaction, it needs to reserve enough for inode
modification in that new transaction. This patch is actually a result of
assertion checks I was getting with more accurate transaction restart
handling implemented later in this series...

I agree we can actually subtract 3 from
ext4_blocks_for_truncate(inode)+extra_credits when starting the initial
transaction as inode changes get double-accounted there. I can do that
and I'll also update the changelog to explain this better.

Jan Kara <>

Powered by blists - more mailing lists