From ec0c4274e33c0373e476b73e01995c53128f1257 Mon Sep 17 00:00:00 2001 From: Kees Cook <keescook@chromium.org> Date: Fri, 23 Mar 2012 12:08:55 -0700 Subject: [PATCH] futex: Mark get_robust_list as deprecated Notify get_robust_list users that the syscall is going away. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kees Cook <keescook@chromium.org> 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 Link: http://lkml.kernel.org/r/20120323190855.GA27213@www.outflux.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- Documentation/feature-removal-schedule.txt | 10 ++++++++++ kernel/futex.c | 2 ++ kernel/futex_compat.c | 2 ++ 3 files changed, 14 insertions(+) diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 0cad4803ffacd..c1be8066ea591 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -529,3 +529,13 @@ When: 3.5 Why: The old kmap_atomic() with two arguments is deprecated, we only keep it for backward compatibility for few cycles and then drop it. Who: Cong Wang <amwang@redhat.com> + +---------------------------- + +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> diff --git a/kernel/futex.c b/kernel/futex.c index d701be57c423f..e2b0fb9a0b3b3 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2449,6 +2449,8 @@ 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 a9642d5286302..83e368b005fc6 100644 --- a/kernel/futex_compat.c +++ b/kernel/futex_compat.c @@ -142,6 +142,8 @@ 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;