linux-ext4 - Re: [PATCH] ext2: adjust block num when retry allocation

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: <20191021091800.GC17810@quack2.suse.cz>
Date:   Mon, 21 Oct 2019 11:18:00 +0200
From:   Jan Kara <jack@...e.cz>
To:     Chengguang Xu <cgxu519@...ernel.net>
Cc:     jack@...e.com, linux-ext4@...r.kernel.org
Subject: Re: [PATCH] ext2: adjust block num when retry allocation

On Mon 21-10-19 07:23:26, Chengguang Xu wrote:
> Set block num to original *count in a case
> of retrying allocation in case num < *count
> 
> Signed-off-by: Chengguang Xu <cgxu519@...ernel.net>
> ---
> Hi Jan,
> 
> This patch is only compile-tested, I'm not sure if this
> kind of unexpected condition which causes reallocation
> will actually happen but baesd on the code the fix seems
> correct and better.

Yeah, you are right that we should reset 'num' back to *count. Although the
practial effect of this is minimal - we take this code path only when the
filesystem is corrupted. But still... Patch applied. Thanks!

								Honza
> 
>  fs/ext2/balloc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c
> index e0cc55164505..924c1c765306 100644
> --- a/fs/ext2/balloc.c
> +++ b/fs/ext2/balloc.c
> @@ -1404,6 +1404,7 @@ ext2_fsblk_t ext2_new_blocks(struct inode *inode, ext2_fsblk_t goal,
>  		 * use.  So we may want to selectively mark some of the blocks
>  		 * as free
>  		 */
> +		num = *count;
>  		goto retry_alloc;
>  	}
>  
> -- 
> 2.21.0
> 
> 
> 
-- 
Jan Kara <jack@...e.com>
SUSE Labs, CR