linux-kernel - Re: [PATCH] ACPI: GTDT: Relax sanity checking on Platform Timers array count

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: <20250213114503.GA11508@willie-the-truck>
Date: Thu, 13 Feb 2025 11:45:04 +0000
From: Will Deacon <will@...nel.org>
To: Lorenzo Pieralisi <lpieralisi@...nel.org>
Cc: Oliver Upton <oliver.upton@...ux.dev>, linux-acpi@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	Hanjun Guo <guohanjun@...wei.com>,
	Sudeep Holla <sudeep.holla@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	Marc Zyngier <maz@...nel.org>,
	Zheng Zengkai <zhengzengkai@...wei.com>
Subject: Re: [PATCH] ACPI: GTDT: Relax sanity checking on Platform Timers
 array count

On Wed, Feb 12, 2025 at 11:33:27AM +0100, Lorenzo Pieralisi wrote:
> > > I think this should be fine as things stand (but see above).
> > > 
> > > It is used in:
> > > 
> > > gtdt_sbsa_gwdt_init() - just to check if there are platform timers entries
> > > 
> > > arch_timer_mem_acpi_init() - to create a temporary array to init arch mem timer
> > > 			     entries (the array is oversized because it
> > > 			     includes watchdog entries in the count)
> > > 
> > > In both cases taking the
> > > 
> > > min(cnt, gtdt->platform_timer_count);
> > > 
> > > should work AFAICS
> > 
> > It was probably worth noting in the changelog that I did this to
> > gracefully handle the reverse of this issue where we could dereference
> > platform timer entries that are within the bounds of the GTDT but exceed
> > gtdt->platform_timer_count.
> 
> Hi Oliver,
> 
> I was about to ask Catalin/Will to pick this up, don't know if you have
> time to update the changelog and send a v2 - a Link: to this thread will
> be added anyway.

I'll pick it up with the Link: tag, no need to resend.

Thanks, both!

Will