bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/powerpc/math-emu/Makefile b/arch/powerpc/math-emu/Makefile
new file mode 100644
index 000000000..603e59c3d
--- /dev/null
+++ b/arch/powerpc/math-emu/Makefile
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0
+math-emu-common-objs = math.o fre.o fsqrt.o fsqrts.o frsqrtes.o mtfsf.o mtfsfi.o
+obj-$(CONFIG_MATH_EMULATION_HW_UNIMPLEMENTED) += $(math-emu-common-objs)
+obj-$(CONFIG_MATH_EMULATION_FULL) += $(math-emu-common-objs) fabs.o fadd.o \
+					fadds.o fcmpo.o fcmpu.o fctiw.o \
+					fctiwz.o fdiv.o fdivs.o  fmadd.o \
+					fmadds.o fmsub.o fmsubs.o fmul.o \
+					fmuls.o fnabs.o fneg.o fnmadd.o \
+					fnmadds.o fnmsub.o fnmsubs.o fres.o \
+					frsp.o fsel.o lfs.o frsqrte.o fsub.o \
+					fsubs.o  mcrfs.o mffs.o mtfsb0.o \
+					mtfsb1.o stfiwx.o stfs.o math.o \
+					fmr.o lfd.o stfd.o
+
+obj-$(CONFIG_SPE)		+= math_efp.o
+
+CFLAGS_fabs.o = -fno-builtin-fabs
+CFLAGS_math.o = -fno-builtin-fabs
+
+ccflags-remove-y = -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+
+ifdef KBUILD_EXTRA_WARN
+CFLAGS_math.o += -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+CFLAGS_math_efp.o += -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+endif