From 8d4b5260d22cc05894d606edd6cfc524661ab6e9 Mon Sep 17 00:00:00 2001
From: David Carlier <devnexen@gmail.com>
Date: Fri, 13 Nov 2020 10:16:55 +0000
Subject: [PATCH] Add MAP_CONCEAL from OpenBSD which has similar purpose but on
 mmap call level.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/13394)
---
 crypto/mem_sec.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/crypto/mem_sec.c b/crypto/mem_sec.c
index f27a759f173..cc4c4e08f6e 100644
--- a/crypto/mem_sec.c
+++ b/crypto/mem_sec.c
@@ -35,6 +35,9 @@
 #  if defined(__FreeBSD__)
 #    define MADV_DONTDUMP MADV_NOCORE
 #  endif
+#  if !defined(MAP_CONCEAL)
+#    define MAP_CONCEAL 0
+#  endif
 # endif
 # if defined(OPENSSL_SYS_LINUX)
 #  include <sys/syscall.h>
@@ -471,7 +474,7 @@ static int sh_init(size_t size, size_t minsize)
 #if !defined(_WIN32)
 # ifdef MAP_ANON
     sh.map_result = mmap(NULL, sh.map_size,
-                         PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0);
+                         PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE|MAP_CONCEAL, -1, 0);
 # else
     {
         int fd;
-- 
2.47.2