github.com/Interlisp.maiko
1
0
Fork 0
mirror of https://github.com/Interlisp/maiko.git synced 2026-02-28 09:17:36 +00:00
Code Issues Projects Releases Wiki Activity

Avoid accessing free block chain pointers when block is not free

Browse Source
This commit is contained in:
Nick Briggs
2023-07-22 15:36:11 -07:00
parent 060420ce42
commit c74e7a0169
1 changed files with 7 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
src/gcfinal.c
View File

@@ -156,8 +156,10 @@ LispPTR findptrsbuffer(LispPTR ptr) {
while (LAddrFromNative(bptr) != NIL) {
if (ptr == bptr->vmempage)
return (LAddrFromNative(bptr));
else
else {
if (bptr->sysnext & 0x0F000000) printf("findptrsbuffer: would have failed %p\n", bptr);
bptr = (struct buf *)NativeAligned4FromLAddr(bptr->sysnext);
}
}
return (NIL);
}
@@ -205,8 +207,6 @@ LispPTR checkarrayblock(LispPTR base, LispPTR free, LispPTR onfreelist) {
{
bbase = (struct arrayblock *)NativeAligned4FromLAddr(base);
btrailer = (struct arrayblock *)NativeAligned4FromLAddr(Trailer(base, bbase));
bfwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->fwd);
bbwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->bkwd);
if (bbase->password != ARRAYBLOCKPASSWORD) {
printarrayblock(base);
error("ARRAYBLOCK password wrong\n");
@@ -228,7 +228,10 @@ LispPTR checkarrayblock(LispPTR base, LispPTR free, LispPTR onfreelist) {
} else if (!onfreelist || (bbase->arlen < MINARRAYBLOCKSIZE))
/* Remaining tests only for free list. */
return (NIL);
else if ((bbwd->fwd != base) || (bfwd->bkwd != base)) {
bfwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->fwd);
bbwd = (struct arrayblock *)NativeAligned4FromLAddr(bbase->bkwd);
if ((bbwd->fwd != base) || (bfwd->bkwd != base)) {
error("ARRAYBLOCK links fouled\n");
} else {
fbl = FreeBlockChainN(bbase->arlen);