Module Name:    src
Committed By:   kamil
Date:           Wed Jul  4 17:50:18 UTC 2018

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

Log Message:
Avoid undefined behavior in mq_send1()

Do not shift a signed integer causing change of the signed bit.

sys/kern/sys_mqueue.c:881:23, 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 -r1.41 -r1.42 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:1.41 src/sys/kern/sys_mqueue.c:1.42
--- src/sys/kern/sys_mqueue.c:1.41	Wed Jul  4 17:39:12 2018
+++ src/sys/kern/sys_mqueue.c	Wed Jul  4 17:50:18 2018
@@ -1,4 +1,4 @@
-/*	$NetBSD: sys_mqueue.c,v 1.41 2018/07/04 17:39:12 kamil Exp $	*/
+/*	$NetBSD: sys_mqueue.c,v 1.42 2018/07/04 17:50:18 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 1.41 2018/07/04 17:39:12 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_mqueue.c,v 1.42 2018/07/04 17:50:18 kamil Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -878,7 +878,7 @@ mq_send1(mqd_t mqdes, const char *msg_pt
 
 		KASSERT(idx != MQ_PQRESQ);
 		TAILQ_INSERT_TAIL(&mq->mq_head[idx], msg, msg_queue);
-		mq->mq_bitmap |= (1 << --idx);
+		mq->mq_bitmap |= (1U << --idx);
 	} else {
 		mqueue_linear_insert(mq, msg);
 	}

Reply via email to