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, 44 insertions, 0 deletions

diff --git a/security/selinux/Makefile b/security/selinux/Makefile
new file mode 100644
index 000000000..72d3baf79
--- /dev/null
+++ b/security/selinux/Makefile
@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for building the SELinux module as part of the kernel tree.
+#
+
+# NOTE: There are a number of improvements that can be made to this Makefile
+# once the kernel requires make v4.3 or greater; the most important feature
+# lacking in older versions of make is support for grouped targets.  These
+# improvements are noted inline in the Makefile below ...
+
+obj-$(CONFIG_SECURITY_SELINUX) := selinux.o
+
+ccflags-y := -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include
+
+ccflags-$(CONFIG_SECURITY_SELINUX_DEBUG) += -DDEBUG
+
+selinux-y := avc.o hooks.o selinuxfs.o netlink.o nlmsgtab.o netif.o \
+	     netnode.o netport.o status.o initcalls.o \
+	     ss/ebitmap.o ss/hashtab.o ss/symtab.o ss/sidtab.o ss/avtab.o \
+	     ss/policydb.o ss/services.o ss/conditional.o ss/mls.o ss/context.o
+
+selinux-$(CONFIG_SECURITY_NETWORK_XFRM) += xfrm.o
+selinux-$(CONFIG_NETLABEL) += netlabel.o
+selinux-$(CONFIG_SECURITY_INFINIBAND) += ibpkey.o
+selinux-$(CONFIG_IMA) += ima.o
+
+genhdrs := flask.h av_permissions.h
+
+# see the note above, replace the dependency rule with the one below:
+#  $(addprefix $(obj)/,$(selinux-y)): $(addprefix $(obj)/,$(genhdrs))
+$(addprefix $(obj)/,$(selinux-y)): $(obj)/flask.h
+
+quiet_cmd_genhdrs = GEN     $(addprefix $(obj)/,$(genhdrs))
+      cmd_genhdrs = $< $(addprefix $(obj)/,$(genhdrs))
+
+targets += $(genhdrs)
+
+# see the note above, replace the 'flask.h' rule with the line below:
+#  $(addprefix $(obj)/,$(genhdrs)) &: $(obj)/genheaders FORCE
+$(obj)/flask.h: $(obj)/genheaders FORCE
+	$(call if_changed,genhdrs)
+
+hostprogs := genheaders
+HOST_EXTRACFLAGS += -I$(srctree)/security/selinux/include