Module Name: src
Committed By: kamil
Date: Wed Jul 4 17:39:12 UTC 2018
Modified Files:
src/sys/kern: sys_mqueue.c
Log Message:
Avoid undefined behavior in mq_recv1()
Do not shift a signed integer causing change of the signed bit.
sys/kern/sys_mqueue.c:712:24, left shift of 1 by 31 places cannot be
represented in type 'int'
Detected with Kernel Undefined Behavior Sanitizer.
Reported by <Harry Pantazis>
To generate a diff of this commit:
cvs rdiff -u -r1.40 -r1.41 src/sys/kern/sys_mqueue.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/sys_mqueue.c
diff -u src/sys/kern/sys_mqueue.c:1.40 src/sys/kern/sys_mqueue.c:1.41
--- src/sys/kern/sys_mqueue.c:1.40 Thu Nov 30 20:25:55 2017
+++ src/sys/kern/sys_mqueue.c Wed Jul 4 17:39:12 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_mqueue.c,v 1.40 2017/11/30 20:25:55 christos Exp $ */
+/* $NetBSD: sys_mqueue.c,v 1.41 2018/07/04 17:39:12 kamil Exp $ */
/*
* Copyright (c) 2007-2011 Mindaugas Rasiukevicius <rmind at NetBSD org>
@@ -43,7 +43,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_mqueue.c,v 1.40 2017/11/30 20:25:55 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_mqueue.c,v 1.41 2018/07/04 17:39:12 kamil Exp $");
#include <sys/param.h>
#include <sys/types.h>
@@ -709,7 +709,7 @@ mq_recv1(mqd_t mqdes, void *msg_ptr, siz
/* Unmark the bit, if last message. */
if (__predict_true(idx) && TAILQ_EMPTY(&mq->mq_head[idx])) {
KASSERT((MQ_PQSIZE - idx) == msg->msg_prio);
- mq->mq_bitmap &= ~(1 << --idx);
+ mq->mq_bitmap &= ~(1U << --idx);
}
/* Decrement the counter and signal waiter, if any */
