From: Thomas Weißschuh Date: Mon, 9 Jun 2025 07:39:16 +0000 (+0200) Subject: selftests/nolibc: make stackprotector probing more robust X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b2c765778a2ea953a448816ba7c034f02a2fd6c6;p=thirdparty%2Flinux.git selftests/nolibc: make stackprotector probing more robust nolibc only supports symbol-based stackprotectors, based on the global variable __stack_chk_guard. Support for this differs between architectures and toolchains. Some use the symbol mode by default, some require a flag to enable it and some don't support it at all. Before the nolibc test Makefile required the availability of "-mstack-protector-guard=global" to enable stackprotectors. While this flag makes sure that the correct mode is available it doesn't work where the correct mode is the only supported one and therefore the flag is not implemented. Switch to a more dynamic probing mechanism. This correctly enables stack protectors for mips, loongarch and m68k. Acked-by: Willy Tarreau Link: https://lore.kernel.org/r/20250609-nolibc-stackprotector-robust-v1-1-a1cfc92a568a@weissschuh.net Signed-off-by: Thomas Weißschuh --- diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile index 94176ffe46463..147ce411b46ac 100644 --- a/tools/testing/selftests/nolibc/Makefile +++ b/tools/testing/selftests/nolibc/Makefile @@ -195,7 +195,10 @@ CFLAGS_sparc32 = $(call cc-option,-m32) ifeq ($(origin XARCH),command line) CFLAGS_XARCH = $(CFLAGS_$(XARCH)) endif -CFLAGS_STACKPROTECTOR ?= $(call cc-option,-mstack-protector-guard=global $(call cc-option,-fstack-protector-all)) +_CFLAGS_STACKPROTECTOR = $(call cc-option,-fstack-protector-all) $(call cc-option,-mstack-protector-guard=global) +CFLAGS_STACKPROTECTOR ?= $(call try-run, \ + echo 'void foo(void) {}' | $(CC) -x c - -o - -S $(CLANG_CROSS_FLAGS) $(_CFLAGS_STACKPROTECTOR) | grep -q __stack_chk_guard, \ + $(_CFLAGS_STACKPROTECTOR)) CFLAGS_SANITIZER ?= $(call cc-option,-fsanitize=undefined -fsanitize-trap=all) CFLAGS ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wextra \ $(call cc-option,-fno-stack-protector) $(call cc-option,-Wmissing-prototypes) \