From 3f5016f60e3ce7fd5c2883cf65dbbc9fbdbf9300 Mon Sep 17 00:00:00 2001
From: SirOlaf <34164198+SirOlaf@users.noreply.github.com>
Date: Mon, 8 Jul 2024 11:15:53 +0200
Subject: [PATCH] Adjust the correct chunk's free space in allocator (#23795)

Fixes #23788
---
 lib/system/alloc.nim | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/system/alloc.nim b/lib/system/alloc.nim
index cc4a24d8fc..94c747e0bb 100644
--- a/lib/system/alloc.nim
+++ b/lib/system/alloc.nim
@@ -865,7 +865,7 @@ proc rawAlloc(a: var MemRegion, requestedSize: int): pointer =
         when not defined(gcDestructors):
           sysAssert(c.freeList.zeroField == 0, "rawAlloc 8")
         c.freeList = c.freeList.next
-      dec(c.free, size)
+      dec(cast[PSmallChunk](pageAddr(result)).free, size)
       sysAssert((cast[int](result) and (MemAlign-1)) == 0, "rawAlloc 9")
       sysAssert(allocInv(a), "rawAlloc: end c != nil")
     sysAssert(allocInv(a), "rawAlloc: before c.free < size")
@@ -948,7 +948,7 @@ proc rawDealloc(a: var MemRegion, p: pointer) =
         inc(c.free, s)
       else:
         inc(c.free, s)
-        if c.free == SmallChunkSize-smallChunkOverhead():
+        if c.free == SmallChunkSize-smallChunkOverhead() and a.freeSmallChunks[s div MemAlign] == c:
           listRemove(a.freeSmallChunks[s div MemAlign], c)
           c.size = SmallChunkSize
           freeBigChunk(a, cast[PBigChunk](c))