linux-kernel - Re: [PATCH 4/5] uas: add dead request list

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: <1378365995.4058.18.camel@linux-fkkt.site>
Date:	Thu, 05 Sep 2013 09:26:35 +0200
From:	Oliver Neukum <oliver@...kum.org>
To:	Gerd Hoffmann <kraxel@...hat.com>
Cc:	linux-usb@...r.kernel.org, Matthew Wilcox <willy@...ux.intel.com>,
	Sarah Sharp <sarah.a.sharp@...ux.intel.com>,
	Matthew Dharm <mdharm-usb@...-eyed-alien.net>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	"open list:USB ATTACHED SCSI" <linux-scsi@...r.kernel.org>,
	"open list:USB MASS STORAGE..." 
	<usb-storage@...ts.one-eyed-alien.net>,
	open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 4/5] uas: add dead request list

On Mon, 2013-09-02 at 13:25 +0200, Gerd Hoffmann wrote:
> +static void uas_zap_dead(struct uas_dev_info *devinfo)
> +{
> +       struct uas_cmd_info *cmdinfo;
> +       struct uas_cmd_info *temp;
> +       struct list_head list;
> +       unsigned long flags;
> +
> +       spin_lock_irq(&uas_lists_lock);
> +       list_replace_init(&uas_dead_list, &list);
> +       spin_unlock_irq(&uas_lists_lock);

This looks like a window for a race.

> +       spin_lock_irqsave(&devinfo->lock, flags);
> +       list_for_each_entry_safe(cmdinfo, temp, &list, dead) {
> +  

What happens if list entries are on the private list, when
the function is called for another device? It looks to me like
the di==devinfo test could put them back on the list although
they would need to be canceled.

	Regards
		Oliver


--
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/