linux-kernel - Re: [patch] mm: xip/ext2 fix block allocation race

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: <48A9541C.9050506@de.ibm.com>
Date:	Mon, 18 Aug 2008 12:51:08 +0200
From:	Carsten Otte <cotte@...ibm.com>
To:	Nick Piggin <npiggin@...e.de>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	borntrae@...ux.vnet.ibm.com, Jared Hulbert <jaredeh@...il.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linux Memory Management List <linux-mm@...ck.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Hugh Dickins <hugh@...itas.com>
Subject: Re: [patch] mm: xip/ext2 fix block allocation race

Nick Piggin wrote:
> XIP can call into get_xip_mem concurrently with the same file,offset with
> create=1.  This usually maps down to get_block, which expects the page lock
> to prevent such a situation. This causes ext2 to explode for one reason or
> another.
> 
> Serialise those calls for the moment. For common usages today, I suspect
> get_xip_mem rarely is called to create new blocks. In future as XIP
> technologies evolve we might need to look at which operations require
> scalability, and rework the locking to suit.
> 
> Signed-off-by: Nick Piggin <npiggin@...e.de>
Acked-by: Carsten Otte <cotte@...ibm.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/