mainline: ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
--->8---
commit ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
Author: Eric Paris <[email protected]>
Date: Tue Dec 4 23:45:31 2007 -0800
VM/Security: add security hook to do_brk
Given a specifically crafted binary do_brk() can be used to get low pages
available in userspace virtual memory and can thus be used to circumvent
the mmap_min_addr low memory protection. Add security checks in do_brk().
Signed-off-by: Eric Paris <[email protected]>
Acked-by: Alan Cox <[email protected]>
Cc: Stephen Smalley <[email protected]>
Cc: James Morris <[email protected]>
Cc: Chris Wright <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/mmap.c b/mm/mmap.c
index facc1a7..acfc13f 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1934,6 +1934,10 @@ unsigned long do_brk(unsigned long addr, unsigned long le
if (is_hugepage_only_range(mm, addr, len))
return -EINVAL;
+ error = security_file_mmap(0, 0, 0, 0, addr, 1);
+ if (error)
+ return error;
+
flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
error = arch_mmap_check(addr, len, flags);
---8<---
--
Thanks,
Oliver
http://nvd.nist.gov/nvd.cfm?cvename=CVE-2007-6434
On 2/4/08, Oliver Pinter <[email protected]> wrote:
> mainline: ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
>
> --->8---
> commit ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
> Author: Eric Paris <[email protected]>
> Date: Tue Dec 4 23:45:31 2007 -0800
>
> VM/Security: add security hook to do_brk
>
> Given a specifically crafted binary do_brk() can be used to get low
> pages
> available in userspace virtual memory and can thus be used to circumvent
> the mmap_min_addr low memory protection. Add security checks in
> do_brk().
>
> Signed-off-by: Eric Paris <[email protected]>
> Acked-by: Alan Cox <[email protected]>
> Cc: Stephen Smalley <[email protected]>
> Cc: James Morris <[email protected]>
> Cc: Chris Wright <[email protected]>
> Signed-off-by: Andrew Morton <[email protected]>
> Signed-off-by: Linus Torvalds <[email protected]>
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index facc1a7..acfc13f 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1934,6 +1934,10 @@ unsigned long do_brk(unsigned long addr, unsigned
> long le
> if (is_hugepage_only_range(mm, addr, len))
> return -EINVAL;
>
> + error = security_file_mmap(0, 0, 0, 0, addr, 1);
> + if (error)
> + return error;
> +
> flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
>
> error = arch_mmap_check(addr, len, flags);
> ---8<---
> --
> Thanks,
> Oliver
>
--
Thanks,
Oliver
sorry, drop this ..
/usr/data/source/oliver/build/linux-2.6.22.y-rcX-stable/mm/mmap.c: In
function 'do_brk':
/usr/data/source/oliver/build/linux-2.6.22.y-rcX-stable/mm/mmap.c:1889:
error: too many arguments to function 'security_file_mmap'
make[6]: *** [mm/mmap.o] Error 1
make[5]: *** [mm] Error 2
On 2/4/08, Oliver Pinter <[email protected]> wrote:
> mainline: ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
>
> --->8---
> commit ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
> Author: Eric Paris <[email protected]>
> Date: Tue Dec 4 23:45:31 2007 -0800
>
> VM/Security: add security hook to do_brk
>
> Given a specifically crafted binary do_brk() can be used to get low
> pages
> available in userspace virtual memory and can thus be used to circumvent
> the mmap_min_addr low memory protection. Add security checks in
> do_brk().
>
> Signed-off-by: Eric Paris <[email protected]>
> Acked-by: Alan Cox <[email protected]>
> Cc: Stephen Smalley <[email protected]>
> Cc: James Morris <[email protected]>
> Cc: Chris Wright <[email protected]>
> Signed-off-by: Andrew Morton <[email protected]>
> Signed-off-by: Linus Torvalds <[email protected]>
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index facc1a7..acfc13f 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -1934,6 +1934,10 @@ unsigned long do_brk(unsigned long addr, unsigned
> long le
> if (is_hugepage_only_range(mm, addr, len))
> return -EINVAL;
>
> + error = security_file_mmap(0, 0, 0, 0, addr, 1);
> + if (error)
> + return error;
> +
> flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
>
> error = arch_mmap_check(addr, len, flags);
> ---8<---
> --
> Thanks,
> Oliver
>
--
Thanks,
Oliver
* Oliver Pinter ([email protected]) wrote:
> mainline: ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
>
> --->8---
> commit ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
> Author: Eric Paris <[email protected]>
> Date: Tue Dec 4 23:45:31 2007 -0800
>
> VM/Security: add security hook to do_brk
>
> Given a specifically crafted binary do_brk() can be used to get low pages
> available in userspace virtual memory and can thus be used to circumvent
> the mmap_min_addr low memory protection. Add security checks in do_brk().
All of the low mmap addr stuff isn't added until 2.6.23.
thanks,
-chris
ok, thanks
On 2/4/08, Chris Wright <[email protected]> wrote:
> * Oliver Pinter ([email protected]) wrote:
> > mainline: ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
> >
> > --->8---
> > commit ecaf18c15aac8bb9bed7b7aa0e382fe252e275d5
> > Author: Eric Paris <[email protected]>
> > Date: Tue Dec 4 23:45:31 2007 -0800
> >
> > VM/Security: add security hook to do_brk
> >
> > Given a specifically crafted binary do_brk() can be used to get low
> pages
> > available in userspace virtual memory and can thus be used to
> circumvent
> > the mmap_min_addr low memory protection. Add security checks in
> do_brk().
>
> All of the low mmap addr stuff isn't added until 2.6.23.
>
> thanks,
> -chris
>
--
Thanks,
Oliver
On Mon, Feb 04, 2008 at 10:02:03PM +0100, Oliver Pinter wrote:
> sorry, drop this ..
>
>
> /usr/data/source/oliver/build/linux-2.6.22.y-rcX-stable/mm/mmap.c: In
> function 'do_brk':
> /usr/data/source/oliver/build/linux-2.6.22.y-rcX-stable/mm/mmap.c:1889:
> error: too many arguments to function 'security_file_mmap'
> make[6]: *** [mm/mmap.o] Error 1
> make[5]: *** [mm] Error 2
Please at least build test your patches before you send them to us...
:)
thanks,
greg k-h