arm64: vdso: enable orphan handling for VDSO

Like vmlinux, enable orphan-handling for the VDSO. This can catch
subtle errors that might arise from unexpected sections being included.

Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20220510095834.32394-3-joey.gouly@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index f6e25d7c346aba02c838a922fd5df6026319ef76..bafbf78fab772d62286b895ba1823d366593b914 100644 (file)
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -24,7 +24,13 @@ btildflags-$(CONFIG_ARM64_BTI_KERNEL) += -z force-bti
 # routines, as x86 does (see 6f121e548f83 ("x86, vdso: Reimplement vdso.so
 # preparation in build-time C")).
 ldflags-y := -shared -soname=linux-vdso.so.1 --hash-style=sysv \
-            -Bsymbolic --build-id=sha1 -n $(btildflags-y) -T
+            -Bsymbolic --build-id=sha1 -n $(btildflags-y)
+
+ifdef CONFIG_LD_ORPHAN_WARN
+  ldflags-y += --orphan-handling=warn
+endif
+
+ldflags-y += -T
 
 ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18
 ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO