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, 25 insertions, 0 deletions

diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
new file mode 100644
index 000000000..98c3ad083
--- /dev/null
+++ b/drivers/tee/Kconfig
@@ -0,0 +1,25 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Generic Trusted Execution Environment Configuration
+menuconfig TEE
+	tristate "Trusted Execution Environment support"
+	depends on HAVE_ARM_SMCCC || COMPILE_TEST || CPU_SUP_AMD
+	select CRYPTO_LIB_SHA1
+	select DMA_SHARED_BUFFER
+	select GENERIC_ALLOCATOR
+	help
+	  This implements a generic interface towards a Trusted Execution
+	  Environment (TEE).
+
+if TEE
+
+config TEE_DMABUF_HEAPS
+	bool
+	depends on HAS_DMA && DMABUF_HEAPS
+	default y
+
+source "drivers/tee/optee/Kconfig"
+source "drivers/tee/amdtee/Kconfig"
+source "drivers/tee/tstee/Kconfig"
+source "drivers/tee/qcomtee/Kconfig"
+
+endif