linux-kernel - Re: [PATCH 12/13] xfs: make the calculation generic in xfs_sb_validate_fsb

lists.openwall.net		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]

Message-ID: <uw6wet56alvrcj6erv3fwn3hqjsyijhk4ke7f54yowt3mzkreh@hiov5ttykytu>
Date: Tue, 27 Feb 2024 09:44:46 +0100
From: "Pankaj Raghav (Samsung)" <kernel@...kajraghav.com>
To: Matthew Wilcox <willy@...radead.org>
Cc: linux-xfs@...r.kernel.org, linux-fsdevel@...r.kernel.org, 
	linux-kernel@...r.kernel.org, david@...morbit.com, chandan.babu@...cle.com, 
	akpm@...ux-foundation.org, mcgrof@...nel.org, ziy@...dia.com, hare@...e.de, 
	djwong@...nel.org, gost.dev@...sung.com, linux-mm@...ck.org, 
	Pankaj Raghav <p.raghav@...sung.com>
Subject: Re: [PATCH 12/13] xfs: make the calculation generic in
 xfs_sb_validate_fsb_count()

On Mon, Feb 26, 2024 at 01:21:56PM +0000, Matthew Wilcox wrote:
> On Mon, Feb 26, 2024 at 10:49:35AM +0100, Pankaj Raghav (Samsung) wrote:
> > +	if (check_mul_overflow(nblocks, (1 << sbp->sb_blocklog), &bytes))
> 
> Why would you not use check_shl_overflow()?

This looks better than check_mul_overflow. I will use this in the next
version.
> 
> > +		return -EFBIG;
> > +
> > +	mapping_count = bytes >> PAGE_SHIFT;
> >  	/* Limited by ULONG_MAX of page cache index */
> > -	if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
> > +	if (mapping_count > ULONG_MAX)
> >  		return -EFBIG;
> >  	return 0;
> >  }
> > -- 
> > 2.43.0
> >