diff options
| -rw-r--r-- | config/Config-build.in | 16 | ||||
| -rw-r--r-- | include/hardened-ld-pie.specs | 2 | ||||
| -rw-r--r-- | include/hardening.mk | 7 | ||||
| -rw-r--r-- | package/utils/busybox/Makefile | 3 |
4 files changed, 28 insertions, 0 deletions
diff --git a/config/Config-build.in b/config/Config-build.in index 7ec7653..660da1c 100644 --- a/config/Config-build.in +++ b/config/Config-build.in @@ -184,6 +184,22 @@ menu "Global build settings" this per package by adding PKG_CHECK_FORMAT_SECURITY:=0 in the package Makefile. + config PKG_ASLR_PIE + bool + prompt "User space ASLR PIE compilation" + select BUSYBOX_DEFAULT_PIE + default n + help + Add -fPIC to CFLAGS and -specs=hardened-build-ld to LDFLAGS. + This enables package build as Position Independent Executables (PIE) + to protect against "return-to-text" attacks. This belongs to the + feature of Address Space Layout Randomisation (ASLR), which is + implemented by the kernel and the ELF loader by randomising the + location of memory allocations. This makes memory addresses harder + to predict when an attacker is attempting a memory-corruption exploit. + You can disable this per package by adding PKG_ASLR_PIE:=0 in the package + Makefile. + choice prompt "User space Stack-Smashing Protection" depends on USE_MUSL diff --git a/include/hardened-ld-pie.specs b/include/hardened-ld-pie.specs new file mode 100644 index 0000000..7317b19 --- /dev/null +++ b/include/hardened-ld-pie.specs @@ -0,0 +1,2 @@ +*self_spec: ++ %{no-pie|static|r|shared:;:-pie} diff --git a/include/hardening.mk b/include/hardening.mk index c277081..06a6178 100644 --- a/include/hardening.mk +++ b/include/hardening.mk @@ -6,6 +6,7 @@ # PKG_CHECK_FORMAT_SECURITY ?= 1 +PKG_ASLR_PIE ?= 1 PKG_SSP ?= 1 PKG_FORTIFY_SOURCE ?= 1 PKG_RELRO ?= 1 @@ -15,6 +16,12 @@ ifdef CONFIG_PKG_CHECK_FORMAT_SECURITY TARGET_CFLAGS += -Wformat -Werror=format-security endif endif +ifdef CONFIG_PKG_ASLR_PIE + ifeq ($(strip $(PKG_ASLR_PIE)),1) + TARGET_CFLAGS += -fPIC + TARGET_LDFLAGS += -specs=$(INCLUDE_DIR)/hardened-ld-pie.specs + endif +endif ifdef CONFIG_PKG_CC_STACKPROTECTOR_REGULAR ifeq ($(strip $(PKG_SSP)),1) TARGET_CFLAGS += -fstack-protector diff --git a/package/utils/busybox/Makefile b/package/utils/busybox/Makefile index 8866756..4f85cc9 100644 --- a/package/utils/busybox/Makefile +++ b/package/utils/busybox/Makefile @@ -22,6 +22,9 @@ PKG_BUILD_PARALLEL:=1 PKG_CHECK_FORMAT_SECURITY:=0 PKG_INSTALL:=1 +#Busybox use it's own PIE config flag and LDFLAGS are used with ld, not gcc. +PKG_ASLR_PIE:=0 + PKG_LICENSE:=GPL-2.0 PKG_LICENSE_FILES:=LICENSE archival/libarchive/bz/LICENSE PKG_CPE_ID:=cpe:/a:busybox:busybox |