selftests/bpf: Test packet range of pointers sharing an idgrafted

Add tests where two packet pointers share an id and tightening one
pointer's umax from its var_off would put it less than their constant
distance from the other's umax: with an index & 0x38 capped at 50, the
base pointer keeps umax 50, so the pointer 8 bytes further on must keep
umax 58, even though its known bits allow at most 56.

These refused a valid program or accepted an out-of-bounds access before
the fix:

- check the advanced copy, load through the base: valid, was refused;
- check the base, load the byte at base + 1 through a copy advanced by
  8: was accepted;
- check base + 4, load 4 bytes at base + 2 through base + 8: reads two
  bytes past the checked range, was accepted;
- the same as the second with data_meta pointers checked against data:
  was accepted.

These pass with and without the fix and cover nearby paths:

- subtract an unknown scalar from a checked pointer and load below it
  (the range is kept across a new id);
- reach a load through two paths whose checks cover 8 and 7 bytes after
  the loaded pointer; the second path must not be pruned by the first;
- spill a copy of a pointer, check the pointer, fill the copy and load
  one byte past the checked range: the load is refused, and the copy
  has the range of the check.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/security/Makefile b/security/Makefile
new file mode 100644
index 000000000..4601230ba
--- /dev/null
+++ b/security/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the kernel security code
+#
+
+obj-$(CONFIG_KEYS)			+= keys/
+
+# always enable default capabilities
+obj-y					+= commoncap.o
+obj-$(CONFIG_SECURITY) 			+= lsm_syscalls.o
+obj-$(CONFIG_MMU)			+= min_addr.o
+
+# Object file lists
+obj-$(CONFIG_SECURITY)			+= security.o lsm_notifier.o lsm_init.o
+obj-$(CONFIG_SECURITYFS)		+= inode.o
+obj-$(CONFIG_SECURITY_SELINUX)		+= selinux/
+obj-$(CONFIG_SECURITY_SMACK)		+= smack/
+obj-$(CONFIG_HAS_SECURITY_AUDIT)	+= lsm_audit.o
+obj-$(CONFIG_SECURITY_TOMOYO)		+= tomoyo/
+obj-$(CONFIG_SECURITY_APPARMOR)		+= apparmor/
+obj-$(CONFIG_SECURITY_YAMA)		+= yama/
+obj-$(CONFIG_SECURITY_LOADPIN)		+= loadpin/
+obj-$(CONFIG_SECURITY_SAFESETID)       += safesetid/
+obj-$(CONFIG_SECURITY_LOCKDOWN_LSM)	+= lockdown/
+obj-$(CONFIG_CGROUPS)			+= device_cgroup.o
+obj-$(CONFIG_BPF_LSM)			+= bpf/
+obj-$(CONFIG_SECURITY_LANDLOCK)		+= landlock/
+obj-$(CONFIG_SECURITY_IPE)		+= ipe/
+
+# Object integrity file lists
+obj-$(CONFIG_INTEGRITY)			+= integrity/