Module Name:    src
Committed By:   kamil
Date:           Tue Jul  3 12:17:54 UTC 2018

Modified Files:
        src/sys/kern: kern_descrip.c

Log Message:
Avoid unportable signed integer left shift in fd_used()

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:302:26, left shift of 1 by 31 places cannot be 
represented in type 'int'

Reported by <Harry Pantazis>


To generate a diff of this commit:
cvs rdiff -u -r1.231 -r1.232 src/sys/kern/kern_descrip.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.

Modified files:

Index: src/sys/kern/kern_descrip.c
diff -u src/sys/kern/kern_descrip.c:1.231 src/sys/kern/kern_descrip.c:1.232
--- src/sys/kern/kern_descrip.c:1.231	Thu Jun  1 02:45:13 2017
+++ src/sys/kern/kern_descrip.c	Tue Jul  3 12:17:54 2018
@@ -1,4 +1,4 @@
-/*	$NetBSD: kern_descrip.c,v 1.231 2017/06/01 02:45:13 chs Exp $	*/
+/*	$NetBSD: kern_descrip.c,v 1.232 2018/07/03 12:17:54 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 1.231 2017/06/01 02:45:13 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_descrip.c,v 1.232 2018/07/03 12:17:54 kamil Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -293,17 +293,17 @@ fd_used(filedesc_t *fdp, unsigned fd)
 	ff = fdp->fd_dt->dt_ff[fd];
 
 	KASSERT(mutex_owned(&fdp->fd_lock));
-	KASSERT((fdp->fd_lomap[off] & (1 << (fd & NDENTRYMASK))) == 0);
+	KASSERT((fdp->fd_lomap[off] & (1U << (fd & NDENTRYMASK))) == 0);
 	KASSERT(ff != NULL);
 	KASSERT(ff->ff_file == NULL);
 	KASSERT(!ff->ff_allocated);
 
 	ff->ff_allocated = true;
-	fdp->fd_lomap[off] |= 1 << (fd & NDENTRYMASK);
+	fdp->fd_lomap[off] |= 1U << (fd & NDENTRYMASK);
 	if (__predict_false(fdp->fd_lomap[off] == ~0)) {
 		KASSERT((fdp->fd_himap[off >> NDENTRYSHIFT] &
-		    (1 << (off & NDENTRYMASK))) == 0);
-		fdp->fd_himap[off >> NDENTRYSHIFT] |= 1 << (off & NDENTRYMASK);
+		    (1U << (off & NDENTRYMASK))) == 0);
+		fdp->fd_himap[off >> NDENTRYSHIFT] |= 1U << (off & NDENTRYMASK);
 	}
 
 	if ((int)fd > fdp->fd_lastfile) {

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