From: Maria Matejka <mq@ucw.cz>
Date: Thu, 20 Apr 2023 17:33:00 +0000 (+0200)
Subject: Linpool: Fix lp_restore()
X-Git-Tag: v2.13~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=335409248ea932e93ce4361564b8e92d0b83b071;p=thirdparty%2Fbird.git

Linpool: Fix lp_restore()

When lp_save() is called on an empty linpool, then some allocation is
done, then lp_restore() is called, the linpool is restored but the used
chunks are inaccessible. Fix it.
---

diff --git a/lib/mempool.c b/lib/mempool.c
index 7c306e991..9d4404f7c 100644
--- a/lib/mempool.c
+++ b/lib/mempool.c
@@ -240,9 +240,9 @@ lp_restore(linpool *m, lp_state *p)
   struct lp_chunk *c;
 
   /* Move ptr to the saved pos and free all newer large chunks */
-  m->current = c = p->current;
-  m->ptr = p->ptr;
-  m->end = c ? c->data + LP_DATA_SIZE : NULL;
+  m->current = c = p->current ?: m->first;
+  m->ptr = p->ptr ?: (c ? c->data : NULL);
+  m->end = c ? (c->data + LP_DATA_SIZE) : NULL;
   m->total_large = p->total_large;
 
   while ((c = m->first_large) && (c != p->large))