[kernel-hardening] Re: [PATCH] Revert "futex: Mark get_robust_list as deprecated"

[ebiederm@xmission.com (Eric W. Biederman)]

Richard Weinberger <richard@nod.at> writes:

> get_robust_list has at least two valid use cases.
> 1. checkpoint/restore in userspace
> 2. post mortem analysis

Looks good to me.

Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>

>
> Cc: Randy Dunlap <rdunlap@xenotime.net>
> Cc: Darren Hart <dvhart@linux.intel.com>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Jiri Kosina <jkosina@suse.cz>
> Cc: Eric W. Biederman <ebiederm@xmission.com>
> Cc: David Howells <dhowells@redhat.com>
> Cc: Serge E. Hallyn <serge.hallyn@canonical.com>
> Cc: kernel-hardening@lists.openwall.com
> Cc: spender@grsecurity.net
> Cc: keescook@chromium.org
> Cc: tglx@linutronix.de
> Cc: Cyrill Gorcunov <gorcunov@openvz.org>
> Cc: xemul@parallels.com
> Cc: <stable@vger.kernel.org> # 3.4.x
> Cc: <stable@vger.kernel.org> # 3.5.x
> Link: http://lkml.kernel.org/r/CAFLxGvzPVPyXPwjay4a01q1vx4K4Ht56bHjzswYrr1wvB_1dYw%20%28%29%20mail%20!%20gmail%20!%20com
> Signed-off-by: Richard Weinberger <richard@nod.at>
> ---
>  Documentation/feature-removal-schedule.txt |   10 ----------
>  kernel/futex.c                             |    2 --
>  kernel/futex_compat.c                      |    2 --
>  3 Dateien geändert, 14 Zeilen entfernt(-)
>
> diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
> index afaff31..a25482e 100644
> --- a/Documentation/feature-removal-schedule.txt
> +++ b/Documentation/feature-removal-schedule.txt
> @@ -506,16 +506,6 @@ Who:	Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
>  
>  ----------------------------
>  
> -What:	get_robust_list syscall
> -When:	2013
> -Why:	There appear to be no production users of the get_robust_list syscall,
> -	and it runs the risk of leaking address locations, allowing the bypass
> -	of ASLR. It was only ever intended for debugging, so it should be
> -	removed.
> -Who:	Kees Cook <keescook@chromium.org>
> -
> -----------------------------
> -
>  What:	Removing the pn544 raw driver.
>  When:	3.6
>  Why:	With the introduction of the NFC HCI and SHDL kernel layers, pn544.c
> diff --git a/kernel/futex.c b/kernel/futex.c
> index e2b0fb9..d701be5 100644
> --- a/kernel/futex.c
> +++ b/kernel/futex.c
> @@ -2449,8 +2449,6 @@ SYSCALL_DEFINE3(get_robust_list, int, pid,
>  	if (!futex_cmpxchg_enabled)
>  		return -ENOSYS;
>  
> -	WARN_ONCE(1, "deprecated: get_robust_list will be deleted in 2013.\n");
> -
>  	rcu_read_lock();
>  
>  	ret = -ESRCH;
> diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
> index 83e368b..a9642d5 100644
> --- a/kernel/futex_compat.c
> +++ b/kernel/futex_compat.c
> @@ -142,8 +142,6 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr,
>  	if (!futex_cmpxchg_enabled)
>  		return -ENOSYS;
>  
> -	WARN_ONCE(1, "deprecated: get_robust_list will be deleted in 2013.\n");
> -
>  	rcu_read_lock();
>  
>  	ret = -ESRCH;