netdev - Re: [net] ixgbe: Fix PHC loophole allowing misconfiguration of increment register

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] [day] [month] [year] [list]

Message-Id: <20120617.161629.894603261493065246.davem@davemloft.net>
Date:	Sun, 17 Jun 2012 16:16:29 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	jeffrey.t.kirsher@...el.com
Cc:	jacob.e.keller@...el.com, netdev@...r.kernel.org, gospo@...hat.com,
	sassmann@...hat.com
Subject: Re: [net] ixgbe: Fix PHC loophole allowing misconfiguration of
 increment register

From: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Date: Sun, 17 Jun 2012 02:29:00 -0700

> From: Jacob Keller <jacob.e.keller@...el.com>
> 
> This patch fixes a potential hole when configuring the cycle counter used to
> generate the nanosecond time clock. This clock is based off of the SYSTIME
> registers along with the TIMINCA registers. The TIMINCA register determines
> the increment to be added to the SYSTIME registers every DMA clock tick. This
> register needs to be reconfigured whenever the link-speed changes. However,
> the value calculated stays the same when link is down and when link is up.
> Misconfiguration can occur if the link status changes due to a reset, which
> causes the TIMINCA register to be reset. This reset puts the device in an
> unstable state where the SYSTIME registers stop incrementing and the PTP
> protocol does not function.
> 
> The solution is to double check the TIMINCA value and always reset the value
> if the register is zero. This prevents a misconfiguration bug that halts the
> PHC.
> 
> Signed-off-by: Jacob Keller <jacob.e.keller@...el.com>
> Acked-by: Don Skidmore <donald.c.skidmore@...el.com>
> Tested-by: Phil Schmitt <phillip.j.schmitt@...el.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@...el.com>

Applied, thanks.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html