Commit 34ad88a9 authored by Nathan Chancellor's avatar Nathan Chancellor Committed by Wen Zhiwei
Browse files

powerpc: Adjust adding stack protector flags to KBUILD_CLAGS for clang 

stable inclusion
from stable-v6.6.64
commit c062bba16246032a167f55b084125f20df95624f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IBL4B6

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c062bba16246032a167f55b084125f20df95624f

--------------------------------

commit bee08a9e6ab03caf14481d97b35a258400ffab8f upstream.

After fixing the HAVE_STACKPROTECTER checks for clang's in-progress
per-task stack protector support [1], the build fails during prepare0
because '-mstack-protector-guard-offset' has not been added to
KBUILD_CFLAGS yet but the other '-mstack-protector-guard' flags have.

  clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default
  clang: error: '-mstack-protector-guard=tls' is used without '-mstack-protector-guard-offset', and there is no default
  make[4]: *** [scripts/Makefile.build:229: scripts/mod/empty.o] Error 1
  make[4]: *** [scripts/Makefile.build:102: scripts/mod/devicetable-offsets.s] Error 1

Mirror other architectures and add all '-mstack-protector-guard' flags
to KBUILD_CFLAGS atomically during stack_protector_prepare, which
resolves the issue and allows clang's implementation to fully work with
the kernel.

Cc: stable@vger.kernel.org # 6.1+
Link: https://github.com/llvm/llvm-project/pull/110928

 [1]
Reviewed-by: default avatarKeith Packard <keithp@keithp.com>
Tested-by: default avatarKeith Packard <keithp@keithp.com>
Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241009-powerpc-fix-stackprotector-test-clang-v2-2-12fb86b31857@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarWen Zhiwei <wenzhiwei@kylinos.cn>
parent 46396912

arch/powerpc/Makefile

+4 −9
Original line number Diff line number Diff line
@@ -89,13 +89,6 @@ KBUILD_AFLAGS += -m$(BITS) 
KBUILD_LDFLAGS	+= -m elf$(BITS)$(LDEMULATION)

endif



cflags-$(CONFIG_STACKPROTECTOR)	+= -mstack-protector-guard=tls

ifdef CONFIG_PPC64

cflags-$(CONFIG_STACKPROTECTOR)	+= -mstack-protector-guard-reg=r13

else

cflags-$(CONFIG_STACKPROTECTOR)	+= -mstack-protector-guard-reg=r2

endif



LDFLAGS_vmlinux-y := -Bstatic

LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) := -pie

LDFLAGS_vmlinux-$(CONFIG_RELOCATABLE) += -z notext
@@ -389,9 +382,11 @@ prepare: stack_protector_prepare 
PHONY += stack_protector_prepare

stack_protector_prepare: prepare0

ifdef CONFIG_PPC64

	$(eval KBUILD_CFLAGS += -mstack-protector-guard-offset=$(shell awk '{if ($$2 == "PACA_CANARY") print $$3;}' include/generated/asm-offsets.h))

	$(eval KBUILD_CFLAGS += -mstack-protector-guard=tls -mstack-protector-guard-reg=r13 \

				-mstack-protector-guard-offset=$(shell awk '{if ($$2 == "PACA_CANARY") print $$3;}' include/generated/asm-offsets.h))

else

	$(eval KBUILD_CFLAGS += -mstack-protector-guard-offset=$(shell awk '{if ($$2 == "TASK_CANARY") print $$3;}' include/generated/asm-offsets.h))

	$(eval KBUILD_CFLAGS += -mstack-protector-guard=tls -mstack-protector-guard-reg=r2 \

				-mstack-protector-guard-offset=$(shell awk '{if ($$2 == "TASK_CANARY") print $$3;}' include/generated/asm-offsets.h))

endif

endif