linux-ext4 - Re: [PATCH -V2 3/5] ext4: Fix the race between read_block_bitmap and mark_diskspace

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]

Date:	Mon, 24 Nov 2008 21:28:01 +0300
From:	Alex Zhuravlev <Alex.Zhuravlev@....COM>
To:	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>
Cc:	Theodore Tso <tytso@....EDU>, cmm@...ibm.com, sandeen@...hat.com,
	linux-ext4@...r.kernel.org
Subject: Re: [PATCH -V2 3/5] ext4: Fix the race between read_block_bitmap and
 mark_diskspace_used

strange ... I'd expect the code to check "uptodate" once buffer is locked. you?

thanks, Alex

Aneesh Kumar K.V wrote:
> @@ -319,9 +319,11 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group)
>  			    block_group, bitmap_blk);
>  		return NULL;
>  	}
> -	if (bh_uptodate_or_lock(bh))
> +	if (buffer_uptodate(bh) &&
> +	    !(desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)))
>  		return bh;
>  
> +	lock_buffer(bh);
>  	spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group));
>  	if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
>  		ext4_init_block_bitmap(sb, bh, block_group, desc);

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html