From 516b11d262711f7b6403c899f18b6ed2cf45062f Mon Sep 17 00:00:00 2001 From: Rolf Neugebauer Date: Fri, 18 Aug 2017 14:53:36 +0100 Subject: [PATCH] kernel: Set DEFAULT_MMAP_MIN_ADDR to 65536/32768 This is a recommended security measure to protect the low portion of virtual memory. On x86_64 the recommended value is 65536 while for arm it shouldn't be higher than 32768. Signed-off-by: Rolf Neugebauer --- kernel/kernel_config-4.9.x | 2 +- kernel/kernel_config-4.9.x-aarch64 | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/kernel_config-4.9.x b/kernel/kernel_config-4.9.x index e5991b2ed..f45f46507 100644 --- a/kernel/kernel_config-4.9.x +++ b/kernel/kernel_config-4.9.x @@ -514,7 +514,7 @@ CONFIG_BOUNCE=y CONFIG_VIRT_TO_BUS=y CONFIG_MMU_NOTIFIER=y CONFIG_KSM=y -CONFIG_DEFAULT_MMAP_MIN_ADDR=4096 +CONFIG_DEFAULT_MMAP_MIN_ADDR=65536 CONFIG_TRANSPARENT_HUGEPAGE=y CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y # CONFIG_TRANSPARENT_HUGEPAGE_MADVISE is not set diff --git a/kernel/kernel_config-4.9.x-aarch64 b/kernel/kernel_config-4.9.x-aarch64 index fe1d7eaee..d1e5c574e 100644 --- a/kernel/kernel_config-4.9.x-aarch64 +++ b/kernel/kernel_config-4.9.x-aarch64 @@ -479,7 +479,7 @@ CONFIG_PHYS_ADDR_T_64BIT=y CONFIG_BOUNCE=y CONFIG_MMU_NOTIFIER=y CONFIG_KSM=y -CONFIG_DEFAULT_MMAP_MIN_ADDR=4096 +CONFIG_DEFAULT_MMAP_MIN_ADDR=32768 CONFIG_TRANSPARENT_HUGEPAGE=y CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y # CONFIG_TRANSPARENT_HUGEPAGE_MADVISE is not set