linux-hardening - Re: [PATCH 1/3] usercopy: Handle vm_map

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, 13 Jun 2022 19:52:20 +0800
From:   Baoquan He <bhe@...hat.com>
To:     Uladzislau Rezki <urezki@...il.com>
Cc:     "Matthew Wilcox (Oracle)" <willy@...radead.org>,
        Kees Cook <keescook@...omium.org>, linux-mm@...ck.org,
        Zorro Lang <zlang@...hat.com>, linux-xfs@...r.kernel.org,
        linux-hardening@...r.kernel.org
Subject: Re: [PATCH 1/3] usercopy: Handle vm_map_ram() areas

On 06/13/22 at 12:00pm, Uladzislau Rezki wrote:
> > vmalloc does not allocate a vm_struct for vm_map_ram() areas.  That causes
> > us to deny usercopies from those areas.  This affects XFS which uses
> > vm_map_ram() for its directories.
> > 
> > Fix this by calling find_vmap_area() instead of find_vm_area().
> > 
> > Fixes: 0aef499f3172 ("mm/usercopy: Detect vmalloc overruns")
> > Signed-off-by: Matthew Wilcox (Oracle) <willy@...radead.org>
> > ---
> >  include/linux/vmalloc.h | 1 +
> >  mm/usercopy.c           | 8 +++++---
> >  mm/vmalloc.c            | 2 +-
> >  3 files changed, 7 insertions(+), 4 deletions(-)
> > 
> > diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
> > index b159c2789961..096d48aa3437 100644
> > --- a/include/linux/vmalloc.h
> > +++ b/include/linux/vmalloc.h
> > @@ -215,6 +215,7 @@ extern struct vm_struct *__get_vm_area_caller(unsigned long size,
> >  void free_vm_area(struct vm_struct *area);
> >  extern struct vm_struct *remove_vm_area(const void *addr);
> >  extern struct vm_struct *find_vm_area(const void *addr);
> > +struct vmap_area *find_vmap_area(unsigned long addr);
> Make it "extern" since it becomes globally visible?

extern is not suggested any more to add for function declaration in
header file, and removing it doesn't impact thing.

> 
> --
> Uladzislau Rezki
>