summaryrefslogtreecommitdiff
path: root/arch/s390
diff options
context:
space:
mode:
authorSven Schnelle <svens@linux.ibm.com>2021-11-11 10:58:26 +0100
committerHeiko Carstens <hca@linux.ibm.com>2021-11-16 12:29:19 +0100
commit00b55eaf45549ce26424224d069a091c7e5d8bac (patch)
tree15e458607b3029c418c73bbc933ed29d63e8c825 /arch/s390
parent7b737adc10d269e7fdf714ae2caa2281b6a801cf (diff)
s390/vdso: filter out -mstack-guard and -mstack-size
When CONFIG_VMAP_STACK is disabled, the user can enable CONFIG_STACK_CHECK, which adds a stack overflow check to each C function in the kernel. This is also done for functions in the vdso page. These functions are run in user context and user stack sizes are usually different to what the kernel uses. This might trigger the stack check although the stack size is valid. Therefore filter the -mstack-guard and -mstack-size flags when compiling vdso C files. Cc: stable@kernel.org # 5.10+ Fixes: 4bff8cb54502 ("s390: convert to GENERIC_VDSO") Reported-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/Makefile10
-rw-r--r--arch/s390/kernel/vdso64/Makefile5
2 files changed, 9 insertions, 6 deletions
diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index 69c45f600273..609e3697324b 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -77,10 +77,12 @@ KBUILD_AFLAGS_DECOMPRESSOR += $(aflags-y)
KBUILD_CFLAGS_DECOMPRESSOR += $(cflags-y)
ifneq ($(call cc-option,-mstack-size=8192 -mstack-guard=128),)
-cflags-$(CONFIG_CHECK_STACK) += -mstack-size=$(STACK_SIZE)
-ifeq ($(call cc-option,-mstack-size=8192),)
-cflags-$(CONFIG_CHECK_STACK) += -mstack-guard=$(CONFIG_STACK_GUARD)
-endif
+ CC_FLAGS_CHECK_STACK := -mstack-size=$(STACK_SIZE)
+ ifeq ($(call cc-option,-mstack-size=8192),)
+ CC_FLAGS_CHECK_STACK += -mstack-guard=$(CONFIG_STACK_GUARD)
+ endif
+ export CC_FLAGS_CHECK_STACK
+ cflags-$(CONFIG_CHECK_STACK) += $(CC_FLAGS_CHECK_STACK)
endif
ifdef CONFIG_EXPOLINE
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
index e7d911780935..9e2b95a222a9 100644
--- a/arch/s390/kernel/vdso64/Makefile
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -8,8 +8,9 @@ ARCH_REL_TYPE_ABS += R_390_GOT|R_390_PLT
include $(srctree)/lib/vdso/Makefile
obj-vdso64 = vdso_user_wrapper.o note.o
obj-cvdso64 = vdso64_generic.o getcpu.o
-CFLAGS_REMOVE_getcpu.o = -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE)
-CFLAGS_REMOVE_vdso64_generic.o = -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE)
+VDSO_CFLAGS_REMOVE := -pg $(CC_FLAGS_FTRACE) $(CC_FLAGS_EXPOLINE) $(CC_FLAGS_CHECK_STACK)
+CFLAGS_REMOVE_getcpu.o = $(VDSO_CFLAGS_REMOVE)
+CFLAGS_REMOVE_vdso64_generic.o = $(VDSO_CFLAGS_REMOVE)
# Build rules