On Tue, Jan 12, 2010 at 02:24:20PM -0500, Stephen Smalley wrote:
On Mon, 2010-01-11 at 14:55 -0500, Dave Jones wrote:
> We've carried this diff in Fedora for a few years now..
>
> --- linux-2.6.26.noarch/security/selinux/hooks.c~ 2008-09-25 14:11:17.000000000
-0400
> +++ linux-2.6.26.noarch/security/selinux/hooks.c 2008-09-25 14:12:17.000000000
-0400
> @@ -3018,7 +3018,6 @@ static int file_map_prot_check(struct fi
> const struct cred *cred = current_cred();
> int rc = 0;
>
> -#ifndef CONFIG_PPC32
> if ((prot & PROT_EXEC) && (!file || (!shared && (prot &
PROT_WRITE)))) {
> /*
> * We are making executable an anonymous mapping or a
> @@ -3029,7 +3028,6 @@ static int file_map_prot_check(struct fi
> if (rc)
> goto error;
> }
> -#endif
>
> if (file) {
> /* read access is always possible with a mapping */
> @@ -3024,7 +3022,6 @@ static int selinux_file_mprotect(struct
> if (selinux_checkreqprot)
> prot = reqprot;
>
> -#ifndef CONFIG_PPC32
> if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
> rc = 0;
> if (vma->vm_start >= vma->vm_mm->start_brk &&
> @@ -3049,7 +3046,6 @@ static int selinux_file_mprotect(struct
> if (rc)
> return rc;
> }
> -#endif
>
> return file_map_prot_check(vma->vm_file, prot,
vma->vm_flags&VM_SHARED);
> }
>
>
>
> This needs a fixed toolchain, and a userspace rebuild to work.
> For these reasons, it's had difficulty getting upstream.
>
> Fedora has a new enough toolchain, and has been rebuilt, so we don't need
> the ifdefs. Other distros don't/haven't, and this patch would break them
> if pushed upstream.
>
> Could we do something like the (untested) diff below instead,
> which might be more palatable to upstream, allowing us to stop
> carrying it ?
>
> Dave
>
> diff --git a/security/selinux/Kconfig b/security/selinux/Kconfig
> index bca1b74..83a9675 100644
> --- a/security/selinux/Kconfig
> +++ b/security/selinux/Kconfig
> @@ -131,3 +131,10 @@ config SECURITY_SELINUX_POLICYDB_VERSION_MAX_VALUE
> installed under /etc/selinux/$SELINUXTYPE/policy, where
> SELINUXTYPE is defined in your /etc/selinux/config.
>
> +config SELINUX_NEW_ENOUGH_TOOLCHAIN
> + bool "SELinux mprotect checks"
> + default n if PPC32
> + help
> + This option requires a modern toolchain (FIXME: Version?)
> + and a userspace rebuild to work.
> +
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index 9a2ee84..e805df7 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -3009,7 +3009,7 @@ static int file_map_prot_check(struct file *file, unsigned
long prot, int shared
> const struct cred *cred = current_cred();
> int rc = 0;
>
> -#ifndef CONFIG_PPC32
> +#ifdef CONFIG_SELINUX_NEW_ENOUGH_TOOLCHAIN
> if ((prot & PROT_EXEC) && (!file || (!shared && (prot &
PROT_WRITE)))) {
> /*
> * We are making executable an anonymous mapping or a
> @@ -3081,7 +3081,7 @@ static int selinux_file_mprotect(struct vm_area_struct *vma,
> if (selinux_checkreqprot)
> prot = reqprot;
>
> -#ifndef CONFIG_PPC32
> +#ifdef CONFIG_SELINUX_NEW_ENOUGH_TOOLCHAIN
> if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
> int rc = 0;
> if (vma->vm_start >= vma->vm_mm->start_brk &&
IMHO, we should just do one of the following:
1) Push the original diff (i.e. drop the #ifndef CONFIG_PPC32) upstream
and see if anyone complains.
-or-
2) Drop the diff altogether and forget about exec* checking on ppc32.
I wouldn't favor the new option.
So I remembered this thread yesterday, after spot posted a sparc variant
http://marc.info/?l=linux-sparc&m=126946771412359&w=2
which adds an additional ifdef clause.
any further thoughts on cleaning up this mess?
option 2 seems not practical if spot wants to *add* the new ifdef.
Dave