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, 64 insertions, 0 deletions

diff --git a/arch/powerpc/crypto/Kconfig b/arch/powerpc/crypto/Kconfig
new file mode 100644
index 000000000..b247f7ed9
--- /dev/null
+++ b/arch/powerpc/crypto/Kconfig
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: GPL-2.0
+
+menu "Accelerated Cryptographic Algorithms for CPU (powerpc)"
+
+config CRYPTO_AES_PPC_SPE
+	tristate "Ciphers: AES, modes: ECB/CBC/CTR/XTS (SPE)"
+	depends on SPE
+	select CRYPTO_LIB_AES
+	select CRYPTO_SKCIPHER
+	help
+	  Length-preserving ciphers: AES with ECB, CBC, CTR, and XTS modes
+
+	  Architecture: powerpc using:
+	  - SPE (Signal Processing Engine) extensions
+
+	  SPE is available for:
+	  - Processor Type: Freescale 8500
+	  - CPU selection: e500 (8540)
+
+	  This module should only be used for low power (router) devices
+	  without hardware AES acceleration (e.g. caam crypto). It reduces the
+	  size of the AES tables from 16KB to 8KB + 256 bytes and mitigates
+	  timining attacks. Nevertheless it might be not as secure as other
+	  architecture specific assembler implementations that work on 1KB
+	  tables or 256 bytes S-boxes.
+
+config CRYPTO_AES_GCM_P10
+	tristate "Stitched AES/GCM acceleration support on P10 or later CPU (PPC)"
+	depends on PPC64 && CPU_LITTLE_ENDIAN && VSX
+	select CRYPTO_LIB_AES
+	select CRYPTO_ALGAPI
+	select CRYPTO_AEAD
+	select CRYPTO_SKCIPHER
+	select CRYPTO_SIMD
+	help
+	  AEAD cipher: AES cipher algorithms (FIPS-197)
+	  GCM (Galois/Counter Mode) authenticated encryption mode (NIST SP800-38D)
+	  Architecture: powerpc64 using:
+	    - little-endian
+	    - Power10 or later features
+
+	  Support for cryptographic acceleration instructions on Power10 or
+	  later CPU. This module supports stitched acceleration for AES/GCM.
+
+config CRYPTO_DEV_VMX
+        bool "Support for VMX cryptographic acceleration instructions"
+        depends on PPC64 && VSX
+        help
+          Support for VMX cryptographic acceleration instructions.
+
+config CRYPTO_DEV_VMX_ENCRYPT
+	tristate "Encryption acceleration support on P8 CPU"
+	depends on CRYPTO_DEV_VMX
+	select CRYPTO_AES
+	select CRYPTO_CBC
+	select CRYPTO_CTR
+	select CRYPTO_XTS
+	default m
+	help
+	  Support for VMX cryptographic acceleration instructions on Power8 CPU.
+	  This module supports acceleration for AES in hardware. If you choose
+	  'M' here, this module will be called vmx-crypto.
+
+endmenu