[src/thorpej-futex]: src/sys/kern futex_func_wait(): If TIMER_ABSTIME, sanity...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e2d59754b816
branches:  thorpej-futex
changeset: 961143:e2d59754b816
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sat Apr 03 21:52:20 2021 +0000

description:
futex_func_wait(): If TIMER_ABSTIME, sanity check that the deadline
provided by the caller is not ridiculous.

diffstat:

 sys/kern/sys_futex.c |  16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diffs (44 lines):

diff -r f230c8734257 -r e2d59754b816 sys/kern/sys_futex.c
--- a/sys/kern/sys_futex.c      Sun Jan 03 16:49:31 2021 +0000
+++ b/sys/kern/sys_futex.c      Sat Apr 03 21:52:20 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sys_futex.c,v 1.11.2.1 2020/11/01 15:16:43 thorpej Exp $       */
+/*     $NetBSD: sys_futex.c,v 1.11.2.2 2021/04/03 21:52:20 thorpej Exp $       */
 
 /*-
  * Copyright (c) 2018, 2019, 2020 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_futex.c,v 1.11.2.1 2020/11/01 15:16:43 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_futex.c,v 1.11.2.2 2021/04/03 21:52:20 thorpej Exp $");
 
 /*
  * Futexes
@@ -1367,7 +1367,15 @@
                return EAGAIN;
 
        /* Determine a deadline on the specified clock.  */
-       if (timeout == NULL || (clkflags & TIMER_ABSTIME) == TIMER_ABSTIME) {
+       if (timeout == NULL) {
+               deadline = timeout;
+       } else if ((clkflags & TIMER_ABSTIME) == TIMER_ABSTIME) {
+               /* Sanity-check the deadline. */
+               if (timeout->tv_sec < 0 ||
+                   timeout->tv_nsec < 0 ||
+                   timeout->tv_nsec >= 1000000000L) {
+                       return EINVAL;
+               }
                deadline = timeout;
        } else {
                struct timespec interval = *timeout;
@@ -1920,7 +1928,7 @@
        }
 
        /*
-        * Now wait.  futex_wait() will dop our op lock once we
+        * Now wait.  futex_wait() will drop our op lock once we
         * are entered into the sleep queue, thus ensuring atomicity
         * of wakes with respect to waits.
         *