From: David Decotigny <ddecotig@gmail.com>
Date: Wed, 15 Jan 2020 07:31:03 +0000 (-0800)
Subject: [pcbios] Fix "out of memory" detection when expanding bottom area
X-Git-Tag: secboot-ioactive-20200925~31
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=45a0ca6de221f8886a9bfb02f0d34af4fc2f1c5d;p=thirdparty%2Fipxe.git

[pcbios] Fix "out of memory" detection when expanding bottom area

This caused iPXE to reject images even when enough memory was
available.

Signed-off-by: David Decotigny <ddecotig@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/arch/x86/interface/pcbios/memtop_umalloc.c b/src/arch/x86/interface/pcbios/memtop_umalloc.c
index f1ab73e29..d7b82189a 100644
--- a/src/arch/x86/interface/pcbios/memtop_umalloc.c
+++ b/src/arch/x86/interface/pcbios/memtop_umalloc.c
@@ -190,7 +190,7 @@ static userptr_t memtop_urealloc ( userptr_t ptr, size_t new_size ) {
 	/* Expand/shrink block if possible */
 	if ( ptr == bottom ) {
 		/* Update block */
-		if ( new_size > ( heap_size - extmem.size ) ) {
+		if ( new_size > ( heap_size + extmem.size ) ) {
 			DBG ( "EXTMEM out of space\n" );
 			return UNULL;
 		}