This tristate choose allows to select to build only some applications
with PIE enabled. On MIPS binaries are getting about 30% bigger when PIE
is activated for the, which is a huge increase.
Network exposed applications like dnsmasq should then be build with PIE
enabled, but some applications which are normally not parsing data from
the network do not have it activated. The regular option should give a
good trade off between extra flash and RAM memory usage and security.
This changes the default from building no applications with PIE to build
some specifically marked applications with PIE enabled. This option is
only activated for targets with bigger flash and RAM to not consume
extra memory on the very small targets. On SDK builds the Regular option
should always be selected, because some tiny targets share the
applications with big targets and only the images for the tiny targets
should contain the none PIE applications, but the images for the normal
targets should use PIE. The shared packages should always use PIE when
it should be normally activated.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Petr Štetiar <ynezz@true.cz>
Fix building packages with LTO when CONFIG_PKG_ASLR_PIE is enabled.
Despite comment of PR lto/80838, it seems that GCC needs -fPIC on linker
command line, even if all objects are -fPIC. This may change as PR
lto/80838 is merged into 8.1
compile-tested: ar71xx, ath79
Fix commits:
6dac92a42e8c11133c9d07940acc34e7397eef69ef16a394d2ef96d1e34a47b42137ce73fc67b614154c0c4006804c51e1e6
Signed-off-by: Julien Dusser <julien.dusser@free.fr>
Introduce a configuration option to build a "hardened" OpenWrt with
ASLR PIE support.
Add new option PKG_ASLR_PIE to enable Address Space Layout Randomization (ASLR)
by building Position Independent Executables (PIE). This new option protects
against "return-to-text" attacks.
Busybox need a special care, link is done with ld, not gcc, leading to
unknown flags. Set BUSYBOX_DEFAULT_PIE instead and disable PKG_ASLR_PIE.
If other failing packages were found, PKG_ASLR_PIE:=0 should be added to
their Makefiles.
Original Work by: Yongkui Han <yonhan@cisco.com>
Signed-off-by: Julien Dusser <julien.dusser@free.fr>
Make musl provide libssp_nonshared.a and make GCC link it unconditionally
if musl is used. This should be a no-op if SSP is disabled and seems to be
the only reliable way of dealing with SSP over all packages due to the mess
that is linkerflags handling in packages.
Signed-off-by: Steven Barth <steven@midlink.org>
SVN-Revision: 46108
