Module Name: src
Committed By: riastradh
Date: Thu Apr 13 08:30:41 UTC 2023
Modified Files:
src/sys/dev/dkwedge: dk.c
Log Message:
dk(4): Explain why dk_rawopens can't overflow and assert it.
To generate a diff of this commit:
cvs rdiff -u -r1.124 -r1.125 src/sys/dev/dkwedge/dk.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/dev/dkwedge/dk.c
diff -u src/sys/dev/dkwedge/dk.c:1.124 src/sys/dev/dkwedge/dk.c:1.125
--- src/sys/dev/dkwedge/dk.c:1.124 Tue Sep 27 17:04:52 2022
+++ src/sys/dev/dkwedge/dk.c Thu Apr 13 08:30:40 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: dk.c,v 1.124 2022/09/27 17:04:52 mlelstv Exp $ */
+/* $NetBSD: dk.c,v 1.125 2023/04/13 08:30:40 riastradh Exp $ */
/*-
* Copyright (c) 2004, 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.124 2022/09/27 17:04:52 mlelstv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.125 2023/04/13 08:30:40 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_dkwedge.h"
@@ -1200,7 +1200,13 @@ dkfirstopen(struct dkwedge_softc *sc, in
} else {
/*
* Retrieve mode from an already opened wedge.
+ *
+ * At this point, dk_rawopens is bounded by the number
+ * of dkwedge devices in the system, which is limited
+ * by autoconf device numbering to INT_MAX. Since
+ * dk_rawopens is unsigned, this can't overflow.
*/
+ KASSERT(sc->sc_parent->dk_rawopens < UINT_MAX);
mode = 0;
LIST_FOREACH(nsc, &sc->sc_parent->dk_wedges, sc_plink) {
if (nsc == sc || nsc->sc_dk.dk_openmask == 0)
