linux-kernel - Re: [PATCH v2] PCI/sysfs: off by two when checking the limit on driver

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: <1420664631.6345.25.camel@redhat.com>
Date:	Wed, 07 Jan 2015 14:03:51 -0700
From:	Alex Williamson <alex.williamson@...hat.com>
To:	Sasha Levin <sasha.levin@...cle.com>
Cc:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
	Alexander Graf <agraf@...e.de>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	"open list:PCI SUBSYSTEM" <linux-pci@...r.kernel.org>
Subject: Re: [PATCH v2] PCI/sysfs: off by two when checking the limit on
 driver_override length

On Wed, 2015-01-07 at 15:52 -0500, Sasha Levin wrote:
> When printing the driver_override parameter when it is 4095 and 4094 bytes
> long the printing code would access invalid memory because we need count+1
> bytes for printing.
> 
> Cc: <stable@...r.kernel.org> # v3.16+
> Fixes: 782a985d ("PCI: Introduce new device binding path using pci_dev.driver_override")
> Cc: Alex Williamson <alex.williamson@...hat.com>
> Cc: Bjorn Helgaas <bhelgaas@...gle.com>
> Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
> Cc: Alexander Graf <agraf@...e.de>
> Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> Signed-off-by: Sasha Levin <sasha.levin@...cle.com>
> ---
>  drivers/pci/pci-sysfs.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index aa012fb..17459ed 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -521,7 +521,8 @@ static ssize_t driver_override_store(struct device *dev,
>  	struct pci_dev *pdev = to_pci_dev(dev);
>  	char *driver_override, *old = pdev->driver_override, *cp;
>  
> -	if (count > PATH_MAX)
> +	/* We need to keep extra room for a newline */
> +	if (count >= (PATH_MAX - 1))
>  		return -EINVAL;
>  
>  	driver_override = kstrndup(buf, count, GFP_KERNEL);

Thanks for posting this Sasha, it fell off my plate with other
activities.

Acked-by: Alex Williamson <alex.williamson@...hat.com>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/