selftests/bpf: Reject graph kptr use after RCU unlockgrafted

Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.

Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.

Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.

Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/block/partitions/Makefile b/block/partitions/Makefile
new file mode 100644
index 000000000..25d424922
--- /dev/null
+++ b/block/partitions/Makefile
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the linux kernel.
+#
+
+obj-$(CONFIG_BLOCK) += core.o
+obj-$(CONFIG_ACORN_PARTITION) += acorn.o
+obj-$(CONFIG_AMIGA_PARTITION) += amiga.o
+obj-$(CONFIG_ATARI_PARTITION) += atari.o
+obj-$(CONFIG_AIX_PARTITION) += aix.o
+obj-$(CONFIG_CMDLINE_PARTITION) += cmdline.o
+obj-$(CONFIG_MAC_PARTITION) += mac.o
+obj-$(CONFIG_LDM_PARTITION) += ldm.o
+obj-$(CONFIG_MSDOS_PARTITION) += msdos.o
+obj-$(CONFIG_OF_PARTITION) += of.o
+obj-$(CONFIG_OSF_PARTITION) += osf.o
+obj-$(CONFIG_SGI_PARTITION) += sgi.o
+obj-$(CONFIG_SUN_PARTITION) += sun.o
+obj-$(CONFIG_ULTRIX_PARTITION) += ultrix.o
+obj-$(CONFIG_IBM_PARTITION) += ibm.o
+obj-$(CONFIG_EFI_PARTITION) += efi.o
+obj-$(CONFIG_KARMA_PARTITION) += karma.o
+obj-$(CONFIG_SYSV68_PARTITION) += sysv68.o