Re: [PATCH] proc: fix mount -t proc -o AAA

[Vasiliy Kulikov <segoon@openwall.com>]

Andrew,

Can you pick this patch, please?

On Fri, Mar 23, 2012 at 19:45 +0100, Arkadiusz Miśkiewicz wrote:
> On Friday 23 of March 2012, Vasiliy Kulikov wrote:
> 
> > Thanks for the report.  Please test the following patch.
> 
> Seems to be working fine, now - thanks!
> 
> 
> 
> > 
> > --------------------------------------------------------------
> > From: Vasiliy Kulikov <segoon@openwall.com>
> > Date: Fri, 23 Mar 2012 20:56:42 +0400
> > Subject: [PATCH] proc: fix mount -t proc -o AAA
> > 
> > proc_parse_options() inside of proc_mount() runs only once at the boot
> > time without any given options.  So, following umount(2)+mount(2) ignore
> > mount options: proc_parse_options() is not called as ->s_root is already
> > initialized.  To fix that parse mount options unconditionally.
> > 
> > Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
> > Reported-by: Arkadiusz Miśkiewicz <a.miskiewicz@gmail.com>
> > ---
> >  fs/proc/root.c |    9 +++++----
> >  1 files changed, 5 insertions(+), 4 deletions(-)
> > 
> > diff --git a/fs/proc/root.c b/fs/proc/root.c
> > index 46a15d8..eed44bf 100644
> > --- a/fs/proc/root.c
> > +++ b/fs/proc/root.c
> > @@ -115,12 +115,13 @@ static struct dentry *proc_mount(struct
> > file_system_type *fs_type, if (IS_ERR(sb))
> >  		return ERR_CAST(sb);
> > 
> > +	if (!proc_parse_options(options, ns)) {
> > +		deactivate_locked_super(sb);
> > +		return ERR_PTR(-EINVAL);
> > +	}
> > +
> >  	if (!sb->s_root) {
> >  		sb->s_flags = flags;
> > -		if (!proc_parse_options(options, ns)) {
> > -			deactivate_locked_super(sb);
> > -			return ERR_PTR(-EINVAL);
> > -		}
> >  		err = proc_fill_super(sb);
> >  		if (err) {
> >  			deactivate_locked_super(sb);
> 
> 
> -- 
> Arkadiusz Miśkiewicz        PLD/Linux Team
> arekm / maven.pl            http://ftp.pld-linux.org/

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments