Patchwork [v3] security_flags: Add the compiler and linker flags that enhance security

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Submitter Saul Wold
Date June 28, 2013, 10:08 p.m.
Message ID <1372457299-8340-1-git-send-email-sgw@linux.intel.com>
Download mbox | patch
Permalink /patch/52687/
State New
Headers show

Comments

Saul Wold - June 28, 2013, 10:08 p.m.
These flags add addition checks at compile, link and runtime to prevent
stack smashing, checking for buffer overflows, and link at program start
to prevent call spoofing later.

This needs to be explicitly enabled by adding the following line to your
local.conf:

require conf/distro/include/security_flags.inc

[YOCTO #3868]

Signed-off-by: Saul Wold <sgw@linux.intel.com>
---
 meta/conf/distro/include/security_flags.inc | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 meta/conf/distro/include/security_flags.inc
Khem Raj - June 28, 2013, 10:22 p.m.
On Jun 28, 2013, at 3:08 PM, Saul Wold <sgw@linux.intel.com> wrote:

> These flags add addition checks at compile, link and runtime to prevent
> stack smashing, checking for buffer overflows, and link at program start
> to prevent call spoofing later.
> 
> This needs to be explicitly enabled by adding the following line to your
> local.conf:
> 
> require conf/distro/include/security_flags.inc
> 
> [YOCTO #3868]
> 
> Signed-off-by: Saul Wold <sgw@linux.intel.com>
> ---
> meta/conf/distro/include/security_flags.inc | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
> create mode 100644 meta/conf/distro/include/security_flags.inc
> 
> diff --git a/meta/conf/distro/include/security_flags.inc b/meta/conf/distro/include/security_flags.inc
> new file mode 100644
> index 0000000..7a7ab52
> --- /dev/null
> +++ b/meta/conf/distro/include/security_flags.inc
> @@ -0,0 +1,26 @@
> +SECURITY_CFLAGS = "-fstack-protector-all -pie -fpie -D_FORTIFY_SOURCE=2"
> +SECURITY_LDFLAGS = "-Wl,-z,relro,-z,now"

these should be weak assignments (?=) I think

> +
> +# Curl seems to check for FORTIFY_SOURCE in CFLAGS, but even assigned
> +# to CPPFLAGS it gets picked into CFLAGS in bitbake.
> +#TARGET_CPPFLAGS_pn-curl += "-D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-curl = "-fstack-protector-all -pie -fpie"
> +SECURITY_CFLAGS_pn-ppp = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-eglibc = ""
> +SECURITY_CFLAGS_pn-eglibc-initial = ""
> +SECURITY_CFLAGS_pn-zlib = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-gcc-runtime = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-libgcc = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-tcl = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-libcap = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-python-smartpm = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-python-imaging = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-python-pycurl = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-kexec-tools = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +
> +# These 2 have text relco errors with the pie options enabled
> +SECURITY_CFLAGS_pn-pulseaudio = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +SECURITY_CFLAGS_pn-ltp = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
> +
> +TARGET_CFLAGS_append = " ${SECURITY_CFLAGS}"
> +TARGET_LDFLAGS_append = " ${SECURITY_LDFLAGS}"
> -- 
> 1.8.1.4
> 
> _______________________________________________
> Openembedded-core mailing list
> Openembedded-core@lists.openembedded.org
> http://lists.openembedded.org/mailman/listinfo/openembedded-core
Ross Burton - July 2, 2013, 10:36 a.m.
On 28 June 2013 23:08, Saul Wold <sgw@linux.intel.com> wrote:
> These flags add addition checks at compile, link and runtime to prevent
> stack smashing, checking for buffer overflows, and link at program start
> to prevent call spoofing later.
>
> This needs to be explicitly enabled by adding the following line to your
> local.conf:
>
> require conf/distro/include/security_flags.inc

Will we be enabling this in Poky?

Ross
Saul Wold - July 2, 2013, 2:38 p.m.
On 07/02/2013 03:36 AM, Burton, Ross wrote:
> On 28 June 2013 23:08, Saul Wold <sgw@linux.intel.com> wrote:
>> These flags add addition checks at compile, link and runtime to prevent
>> stack smashing, checking for buffer overflows, and link at program start
>> to prevent call spoofing later.
>>
>> This needs to be explicitly enabled by adding the following line to your
>> local.conf:
>>
>> require conf/distro/include/security_flags.inc
>
> Will we be enabling this in Poky?
>
No we will not enable by default, but we will do builds with them 
enabled regularly to test for build failures.  They add overhead both in 
binary size and performance.

Sau!

> Ross
>
>

Patch

diff --git a/meta/conf/distro/include/security_flags.inc b/meta/conf/distro/include/security_flags.inc
new file mode 100644
index 0000000..7a7ab52
--- /dev/null
+++ b/meta/conf/distro/include/security_flags.inc
@@ -0,0 +1,26 @@ 
+SECURITY_CFLAGS = "-fstack-protector-all -pie -fpie -D_FORTIFY_SOURCE=2"
+SECURITY_LDFLAGS = "-Wl,-z,relro,-z,now"
+
+# Curl seems to check for FORTIFY_SOURCE in CFLAGS, but even assigned
+# to CPPFLAGS it gets picked into CFLAGS in bitbake.
+#TARGET_CPPFLAGS_pn-curl += "-D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-curl = "-fstack-protector-all -pie -fpie"
+SECURITY_CFLAGS_pn-ppp = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-eglibc = ""
+SECURITY_CFLAGS_pn-eglibc-initial = ""
+SECURITY_CFLAGS_pn-zlib = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-gcc-runtime = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-libgcc = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-tcl = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-libcap = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-python-smartpm = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-python-imaging = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-python-pycurl = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-kexec-tools = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+
+# These 2 have text relco errors with the pie options enabled
+SECURITY_CFLAGS_pn-pulseaudio = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+SECURITY_CFLAGS_pn-ltp = "-fstack-protector-all -D_FORTIFY_SOURCE=2"
+
+TARGET_CFLAGS_append = " ${SECURITY_CFLAGS}"
+TARGET_LDFLAGS_append = " ${SECURITY_LDFLAGS}"