linux-kernel - Re: [PATCH] locks: export device name

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: <20120213163425.dd9adfde.akpm@linux-foundation.org>
Date:	Mon, 13 Feb 2012 16:34:25 -0800
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	dave@....org
Cc:	Matthew Wilcox <matthew@....cx>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] locks: export device name

On Fri, 10 Feb 2012 22:06:07 +0100
Davidlohr Bueso <dave@....org> wrote:

> From: Davidlohr Bueso <dave@....org>
> 
> The lslk(8) program has not been maintained for over a decade and has recently been rewritten as lslocks(8).
> It will be available for the next 2.22 release, in a couple of months. This is a good opportunity to delete
> that nasty WE_CAN_BREAK_LSLK_NOW and start exporting the device name instead of the maj:min numbers.
> 
> For backward compatibility the new version can be in charge of checking older kernel versions and parsing the old
> output if necessary.
> 
> ...
>
> --- a/fs/locks.c
> +++ b/fs/locks.c
> @@ -2199,15 +2199,8 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl,
>  			       : (fl->fl_type & F_WRLCK) ? "WRITE" : "READ ");
>  	}
>  	if (inode) {
> -#ifdef WE_CAN_BREAK_LSLK_NOW
>  		seq_printf(f, "%d %s:%ld ", fl_pid,
>  				inode->i_sb->s_id, inode->i_ino);
> -#else
> -		/* userspace relies on this representation of dev_t ;-( */
> -		seq_printf(f, "%d %02x:%02x:%ld ", fl_pid,
> -				MAJOR(inode->i_sb->s_dev),
> -				MINOR(inode->i_sb->s_dev), inode->i_ino);
> -#endif
>  	} else {
>  		seq_printf(f, "%d <none>:0 ", fl_pid);
>  	}

I don't get it.  This is an immediate and non-back-compatible change to
the format of /proc/locks.  The only way this can avoid breaking things
is if there are no programs or scripts in use by anyone which use
this field.  What am I missing here?

--
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/