hrtimer: check relative timeouts for overflow

Various user space callers ask for relative timeouts. While we fixed
that overflow issue in hrtimer_start(), the sites which convert
relative user space values to absolute timeouts themself were uncovered.

Instead of putting overflow checks into each place add a function
which does the sanity checking and convert all affected callers to use
it.

Thanks to Frans Pop, who reported the problem and tested the fixes.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Frans Pop <elendil@planet.nl>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index 133d558db452..7d5e4b016f39 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -176,7 +176,7 @@ asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val,
 
                 t = timespec_to_ktime(ts);
                 if (cmd == FUTEX_WAIT)
-                        t = ktime_add(ktime_get(), t);
+                        t = ktime_add_safe(ktime_get(), t);
                 tp = &t;
         }
         if (cmd == FUTEX_REQUEUE || cmd == FUTEX_CMP_REQUEUE)