From 38363964fc96008761195984c989b036227e0e5c Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Thu, 29 Aug 2024 16:16:03 +0200 Subject: Makefile: Enable _FORTIFY_SOURCE iff needed On some systems source fortification is enabled whenever code optimization is enabled (e.g. with -O2). Since code fortification is explicitly enabled too (with possibly different value than the system wants, there are three levels [1]), distros are required to patch our Makefile, e.g. [2]. Detect whether fortification is not already enabled and enable it explicitly only if really needed. 1: https://www.gnu.org/software/libc/manual/html_node/Source-Fortification.html 2: https://github.com/gentoo/gentoo/commit/edfeb8763ac56112c59248c62c9cda13e5d01c97 Signed-off-by: Michal Privoznik Signed-off-by: Stefano Brivio --- Makefile | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 01fada4..74a9513 100644 --- a/Makefile +++ b/Makefile @@ -33,9 +33,16 @@ AUDIT_ARCH := $(shell echo $(AUDIT_ARCH) | sed 's/MIPS64EL/MIPSEL64/') AUDIT_ARCH := $(shell echo $(AUDIT_ARCH) | sed 's/HPPA/PARISC/') AUDIT_ARCH := $(shell echo $(AUDIT_ARCH) | sed 's/SH4/SH/') +# On some systems enabling optimization also enables source fortification, +# automagically. Do not override it. +FORTIFY_FLAG := +ifeq ($(shell $(CC) -O2 -dM -E - < /dev/null 2>&1 | grep ' _FORTIFY_SOURCE ' > /dev/null; echo $$?),1) +FORTIFY_FLAG := -D_FORTIFY_SOURCE=2 +endif + FLAGS := -Wall -Wextra -Wno-format-zero-length FLAGS += -pedantic -std=c11 -D_XOPEN_SOURCE=700 -D_GNU_SOURCE -FLAGS += -D_FORTIFY_SOURCE=2 -O2 -pie -fPIE +FLAGS += $(FORTIFY_FLAG) -O2 -pie -fPIE FLAGS += -DPAGE_SIZE=$(shell getconf PAGE_SIZE) FLAGS += -DNETNS_RUN_DIR=\"/run/netns\" FLAGS += -DPASST_AUDIT_ARCH=AUDIT_ARCH_$(AUDIT_ARCH) -- cgit v1.2.3