[src/trunk]: src/lib/libnvmm Fix error handling of realloc, and use memmove b...

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

details:   https://anonhg.NetBSD.org/src/rev/aad0f6e77cd2
branches:  trunk
changeset: 446000:aad0f6e77cd2
user:      maxv <maxv%NetBSD.org@localhost>
date:      Mon Nov 19 21:45:37 2018 +0000

description:
Fix error handling of realloc, and use memmove because the areas overlap;
noted by agc@. These _nvmm_area_add/delete functions don't make a lot of
sense right now and will likely be rewritten to match the behavior
expected by Qemu; but still fix for the time being.

Also fix a collision check while here.

diffstat:

 lib/libnvmm/libnvmm.c |  14 +++++++-------
 1 files changed, 7 insertions(+), 7 deletions(-)

diffs (46 lines):

diff -r 849022750ae1 -r aad0f6e77cd2 lib/libnvmm/libnvmm.c
--- a/lib/libnvmm/libnvmm.c     Mon Nov 19 20:44:51 2018 +0000
+++ b/lib/libnvmm/libnvmm.c     Mon Nov 19 21:45:37 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: libnvmm.c,v 1.1 2018/11/10 09:28:56 maxv Exp $ */
+/*     $NetBSD: libnvmm.c,v 1.2 2018/11/19 21:45:37 maxv Exp $ */
 
 /*
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -60,8 +60,8 @@
                    gpa < mach->areas[i].gpa + mach->areas[i].size) {
                        goto error;
                }
-               if (gpa + size >= mach->areas[i].gpa &&
-                   gpa + size < mach->areas[i].gpa + mach->areas[i].size) {
+               if (gpa + size > mach->areas[i].gpa &&
+                   gpa + size <= mach->areas[i].gpa + mach->areas[i].size) {
                        goto error;
                }
                if (gpa < mach->areas[i].gpa &&
@@ -70,13 +70,13 @@
                }
        }
 
-       mach->nareas++;
-       ptr = realloc(mach->areas, mach->nareas * sizeof(struct nvmm_area));
+       ptr = realloc(mach->areas, (mach->nareas + 1) *
+           sizeof(struct nvmm_area));
        if (ptr == NULL)
                return -1;
        mach->areas = ptr;
 
-       area = &mach->areas[mach->nareas-1];
+       area = &mach->areas[mach->nareas++];
        area->gpa = gpa;
        area->hva = hva;
        area->size = size;
@@ -106,7 +106,7 @@
                return -1;
        }
 
-       memcpy(&mach->areas[i], &mach->areas[i+1],
+       memmove(&mach->areas[i], &mach->areas[i+1],
            (mach->nareas - i - 1) * sizeof(struct nvmm_area));
        mach->nareas--;