From: Maria Matejka <mq@ucw.cz>
Date: Wed, 3 May 2023 16:59:52 +0000 (+0200)
Subject: Fixed cold page cache leak
X-Git-Tag: v3.0-alpha2~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1e998a434909b6ad5506c4b0084b7ad1ef3da2b1;p=thirdparty%2Fbird.git

Fixed cold page cache leak

The empty_pages pointer wasn't being propagated into the ->next pointer
when more empty_pages were to be stored
---

diff --git a/sysdep/unix/alloc.c b/sysdep/unix/alloc.c
index 2205f1527..891a0e69d 100644
--- a/sysdep/unix/alloc.c
+++ b/sysdep/unix/alloc.c
@@ -282,10 +282,13 @@ page_cleanup(void *_ UNUSED)
     if (!empty_pages || (empty_pages->pos == EP_POS_MAX))
     {
       /* There is either no pointer block or the last block is full. We use this block as a pointer block. */
-      empty_pages = (struct empty_pages *) fp;
-      UNPROTECT_PAGE(empty_pages);
-      *empty_pages = (struct empty_pages) {};
-      PROTECT_PAGE(empty_pages);
+      struct empty_pages *ep = (struct empty_pages *) fp;
+      UNPROTECT_PAGE(ep);
+      *ep = (struct empty_pages) {
+	.next = empty_pages,
+      };
+      PROTECT_PAGE(ep);
+      empty_pages = ep;
     }
     else
     {