linux-ext4 - Re: [bugzilla:219548] the kernel crashes when storing an EXT4 file system in a ZRAM device

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z1pjJWkheibiaWuV@casper.infradead.org>
Date: Thu, 12 Dec 2024 04:14:29 +0000
From: Matthew Wilcox <willy@...radead.org>
To: Sergey Senozhatsky <senozhatsky@...omium.org>
Cc: Theodore Ts'o <tytso@....edu>, Christoph Hellwig <hch@...radead.org>,
	Jens Axboe <axboe@...nel.dk>,
	caiqingfu <baicaiaichibaicai@...il.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-ext4@...r.kernel.org, linux-block@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: Re: [bugzilla:219548] the kernel crashes when storing an EXT4 file
 system in a ZRAM device

On Thu, Dec 12, 2024 at 12:58:26PM +0900, Sergey Senozhatsky wrote:
> Hi,
> 
> We've got two reports [1] [2] (could be the same person) which
> suggest that ext4 may change page content while the page is under
> write().  The particular problem here the case when ext4 is on
> the zram device.  zram compresses every page written to it, so if
> the page content can be modified concurrently with zram's compression
> then we can't really use zram with ext4.

Do you set BLK_FEAT_STABLE_WRITES on zram?