[src/trunk]: src/sys/kern Avoid unportable signed integer left shift in fd_un...

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

details:   https://anonhg.NetBSD.org/src/rev/6efdba1bd205
branches:  trunk
changeset: 324442:6efdba1bd205
user:      kamil <kamil%NetBSD.org@localhost>
date:      Tue Jul 03 23:14:57 2018 +0000

description:
Avoid unportable signed integer left shift in fd_unused()

Detected with Kernel Undefined Behavior Sanitizer.

There were at least a single place reported, for consistency fix all the
left bit shift operations.
sys/kern/kern_descrip.c:345:2, left shift of 1 by 31 places cannot be represented in type 'int'
sys/kern/kern_descrip.c:346:28, left shift of 1 by 31 places cannot be represented in type 'int'

Reported by <Harry Pantazis>

diffstat:

 sys/kern/kern_descrip.c |  12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diffs (35 lines):

diff -r b2df2caeb9ea -r 6efdba1bd205 sys/kern/kern_descrip.c
--- a/sys/kern/kern_descrip.c   Tue Jul 03 23:11:06 2018 +0000
+++ b/sys/kern/kern_descrip.c   Tue Jul 03 23:14:57 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_descrip.c,v 1.234 2018/07/03 23:11:06 kamil Exp $ */
+/*     $NetBSD: kern_descrip.c,v 1.235 2018/07/03 23:14:57 kamil Exp $ */
 
 /*-
  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_descrip.c,v 1.234 2018/07/03 23:11:06 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_descrip.c,v 1.235 2018/07/03 23:14:57 kamil Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -338,12 +338,12 @@
 
        if (fdp->fd_lomap[off] == ~0) {
                KASSERT((fdp->fd_himap[off >> NDENTRYSHIFT] &
-                   (1 << (off & NDENTRYMASK))) != 0);
+                   (1U << (off & NDENTRYMASK))) != 0);
                fdp->fd_himap[off >> NDENTRYSHIFT] &=
-                   ~(1 << (off & NDENTRYMASK));
+                   ~(1U << (off & NDENTRYMASK));
        }
-       KASSERT((fdp->fd_lomap[off] & (1 << (fd & NDENTRYMASK))) != 0);
-       fdp->fd_lomap[off] &= ~(1 << (fd & NDENTRYMASK));
+       KASSERT((fdp->fd_lomap[off] & (1U << (fd & NDENTRYMASK))) != 0);
+       fdp->fd_lomap[off] &= ~(1U << (fd & NDENTRYMASK));
        ff->ff_allocated = false;
 
        KASSERT(fd <= fdp->fd_lastfile);