From 2f54c2a841861ba587c9bbdd66d5164b6774d9e5 Mon Sep 17 00:00:00 2001 From: Julien Olivain Date: Sun, 18 Sep 2022 23:21:44 +0200 Subject: [PATCH] security hardening: add support for glibc _FORTIFY_SOURCE=3 A new _FORTIFY_SOURCE=3 level was introduced in glibc, in commit: https://sourceware.org/git/?p=glibc.git;a=commit;h=c43c5796121bc5bcc0867f02e5536874aa8196c1 This commit was first included glibc 2.33. At that time, it was only supported by llvm/clang 9, and not by any released gcc version. To support _FORTIFY_SOURCE=3, the needed gcc features were introduced in version 12. The gcc 12 support was added in glibc commit: https://sourceware.org/git/?p=glibc.git;a=commit;h=86bf0feb0e3ec8e37872f72499d6ae33406561d7 This commit was first included in glibc 2.35. Buildroot updated to glibc 2.35 in commit: https://git.buildroot.org/buildroot/commit/?id=68d0aede597d32816c5b2ff32de0ce33cc14eb93 Buildroot introduced gcc 12 support in commit: https://git.buildroot.org/buildroot/commit/?id=0f1ad4fc93286adaba852c99d6e1c2565b5c4258 Support for _FORTIFY_SOURCE=3 can now be added. Signed-off-by: Julien Olivain Signed-off-by: Yann E. MORIN --- Config.in | 9 +++++++++ package/Makefile.in | 2 ++ 2 files changed, 11 insertions(+) diff --git a/Config.in b/Config.in index 64604a0aed..86699f58c6 100644 --- a/Config.in +++ b/Config.in @@ -930,6 +930,15 @@ config BR2_FORTIFY_SOURCE_2 Also adds checks at run-time (detected buffer overflow terminates the program) +config BR2_FORTIFY_SOURCE_3 + bool "Extended" + depends on BR2_TOOLCHAIN_GCC_AT_LEAST_12 + help + This option sets _FORTIFY_SOURCES to 3 and even more + checking is added compared to level 2. Extends checks at + run-time that can introduce an additional performance + overhead. + endchoice comment "Fortify Source needs a glibc toolchain and optimization" diff --git a/package/Makefile.in b/package/Makefile.in index 43d214bcbe..7f1b00ba24 100644 --- a/package/Makefile.in +++ b/package/Makefile.in @@ -160,6 +160,8 @@ ifeq ($(BR2_FORTIFY_SOURCE_1),y) TARGET_HARDENED += -D_FORTIFY_SOURCE=1 else ifeq ($(BR2_FORTIFY_SOURCE_2),y) TARGET_HARDENED += -D_FORTIFY_SOURCE=2 +else ifeq ($(BR2_FORTIFY_SOURCE_3),y) +TARGET_HARDENED += -D_FORTIFY_SOURCE=3 endif TARGET_CPPFLAGS += -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64