Re: [PATCH] splice: fix user pointer access in get_iovec_page_array()

[Oliver Pinter]

Linux pancs 2.6.22.17-opt2-cve2 #1 SMP Sun Feb 10 16:22:37 CET 2008
i686 GNU/Linux
-----------------------------------
 Linux vmsplice Local Root Exploit
 By qaaz
-----------------------------------
[+] mmap: 0x0 .. 0x1000
[+] page: 0x0
[+] page: 0x20
[+] mmap: 0x4000 .. 0x5000
[+] page: 0x4000
[+] page: 0x4020
[+] mmap: 0x1000 .. 0x2000
[+] page: 0x1000
[+] mmap: 0xb7f95000 .. 0xb7fc7000
[-] vmsplice: Bad address
-----------------------------------
 Linux vmsplice Local Root Exploit
 By qaaz
-----------------------------------
[+] addr: 0xc01112e9
[-] wtf

the patch is good for 2.6.22.y

On 2/11/08, Willy Tarreau <w@xxxxxx> wrote:
> On Sun, Feb 10, 2008 at 04:47:57PM +0200, Pekka J Enberg wrote:
> > From: Bastian Blank <bastian@xxxxxxxxxxxx>
> >
> > The commit 8811930dc74a503415b35c4a79d14fb0b408a361 ("splice: missing user
> > pointer access verification") added access_ok() to
> copy_from_user_mmap_sem()
> > which only ensures we can copy the struct iovecs from userspace to the
> kernel
> > but we also must check whether we can access the actual memory region
> pointed
> > to by the struct iovec to close the local root exploit.
> >
> > Cc: <stable@xxxxxxxxxx>
> > Cc: Jens Axboe <jens.axboe@xxxxxxxxxx>
> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
> > ---
> > Bastian, can I have your Signed-off-by for this, please? Oliver, Niki, can
> > you please confirm this closes the hole?
>
> Pekka, I confirm that it also closes the hole once backported to 2.6.22.
>
> Willy
>
>


-- 
Thanks,
Oliver
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