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, 23 insertions, 0 deletions

diff --git a/samples/rust/Makefile b/samples/rust/Makefile
new file mode 100644
index 000000000..b986b681c
--- /dev/null
+++ b/samples/rust/Makefile
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0
+ccflags-y += -I$(src)				# needed for trace events
+
+obj-$(CONFIG_SAMPLE_RUST_MINIMAL)		+= rust_minimal.o
+obj-$(CONFIG_SAMPLE_RUST_MISC_DEVICE)		+= rust_misc_device.o
+obj-$(CONFIG_SAMPLE_RUST_PRINT)			+= rust_print.o
+obj-$(CONFIG_SAMPLE_RUST_DEBUGFS)		+= rust_debugfs.o
+obj-$(CONFIG_SAMPLE_RUST_DEBUGFS_SCOPED)	+= rust_debugfs_scoped.o
+obj-$(CONFIG_SAMPLE_RUST_DMA)			+= rust_dma.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_I2C)		+= rust_driver_i2c.o
+obj-$(CONFIG_SAMPLE_RUST_I2C_CLIENT)		+= rust_i2c_client.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_PCI)		+= rust_driver_pci.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_PLATFORM)	+= rust_driver_platform.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_USB)		+= rust_driver_usb.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_FAUX)		+= rust_driver_faux.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_AUXILIARY)	+= rust_driver_auxiliary.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_SERDEV)		+= rust_driver_serdev.o
+obj-$(CONFIG_SAMPLE_RUST_CONFIGFS)		+= rust_configfs.o
+obj-$(CONFIG_SAMPLE_RUST_SOC)			+= rust_soc.o
+
+rust_print-y := rust_print_main.o rust_print_events.o
+
+subdir-$(CONFIG_SAMPLE_RUST_HOSTPROGS)		+= hostprogs