Sven Schnelle 00b55eaf45 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>
2021-11-16 12:29:19 +01:00

87 lines
2.6 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
# List of files in the vdso
KCOV_INSTRUMENT := n
ARCH_REL_TYPE_ABS := R_390_COPY|R_390_GLOB_DAT|R_390_JMP_SLOT|R_390_RELATIVE
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
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
targets := $(obj-vdso64) $(obj-cvdso64) vdso64.so vdso64.so.dbg
obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
obj-cvdso64 := $(addprefix $(obj)/, $(obj-cvdso64))
KBUILD_AFLAGS += -DBUILD_VDSO
KBUILD_CFLAGS += -DBUILD_VDSO -DDISABLE_BRANCH_PROFILING
KBUILD_AFLAGS_64 := $(filter-out -m64,$(KBUILD_AFLAGS))
KBUILD_AFLAGS_64 += -m64 -s
KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
KBUILD_CFLAGS_64 += -m64 -fPIC -shared -fno-common -fno-builtin
ldflags-y := -fPIC -shared -soname=linux-vdso64.so.1 \
--hash-style=both --build-id=sha1 -T
$(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_64)
$(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_64)
obj-y += vdso64_wrapper.o
targets += vdso64.lds
CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
# Disable gcov profiling, ubsan and kasan for VDSO code
GCOV_PROFILE := n
UBSAN_SANITIZE := n
KASAN_SANITIZE := n
KCSAN_SANITIZE := n
# Force dependency (incbin is bad)
$(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
# link rule for the .so file, .lds has to be first
$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) $(obj-cvdso64) FORCE
$(call if_changed,ld)
# strip rule for the .so file
$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
$(call if_changed,objcopy)
# assembly rules for the .S files
$(obj-vdso64): %.o: %.S FORCE
$(call if_changed_dep,vdso64as)
$(obj-cvdso64): %.o: %.c FORCE
$(call if_changed_dep,vdso64cc)
# actual build commands
quiet_cmd_vdso64as = VDSO64A $@
cmd_vdso64as = $(CC) $(a_flags) -c -o $@ $<
quiet_cmd_vdso64cc = VDSO64C $@
cmd_vdso64cc = $(CC) $(c_flags) -c -o $@ $<
# install commands for the unstripped file
quiet_cmd_vdso_install = INSTALL $@
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
vdso64.so: $(obj)/vdso64.so.dbg
@mkdir -p $(MODLIB)/vdso
$(call cmd,vdso_install)
vdso_install: vdso64.so
# Generate VDSO offsets using helper script
gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
quiet_cmd_vdsosym = VDSOSYM $@
cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
include/generated/vdso64-offsets.h: $(obj)/vdso64.so.dbg FORCE
$(call if_changed,vdsosym)