From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock 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 Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- include/crypto/b128ops.h | 72 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 include/crypto/b128ops.h (limited to 'include/crypto/b128ops.h') diff --git a/include/crypto/b128ops.h b/include/crypto/b128ops.h new file mode 100644 index 000000000..f3b37cbb3 --- /dev/null +++ b/include/crypto/b128ops.h @@ -0,0 +1,72 @@ +/* b128ops.h - common 128-bit block operations + * + * Copyright (c) 2003, Dr Brian Gladman, Worcester, UK. + * Copyright (c) 2006, Rik Snel + * + * Based on Dr Brian Gladman's (GPL'd) work published at + * http://fp.gladman.plus.com/cryptography_technology/index.htm + * See the original copyright notice below. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + */ +/* + --------------------------------------------------------------------------- + Copyright (c) 2003, Dr Brian Gladman, Worcester, UK. All rights reserved. + + LICENSE TERMS + + The free distribution and use of this software in both source and binary + form is allowed (with or without changes) provided that: + + 1. distributions of this source code include the above copyright + notice, this list of conditions and the following disclaimer; + + 2. distributions in binary form include the above copyright + notice, this list of conditions and the following disclaimer + in the documentation and/or other associated materials; + + 3. the copyright holder's name is not used to endorse products + built using this software without specific written permission. + + ALTERNATIVELY, provided that this notice is retained in full, this product + may be distributed under the terms of the GNU General Public License (GPL), + in which case the provisions of the GPL apply INSTEAD OF those given above. + + DISCLAIMER + + This software is provided 'as is' with no explicit or implied warranties + in respect of its properties, including, but not limited to, correctness + and/or fitness for purpose. + --------------------------------------------------------------------------- + Issue Date: 13/06/2006 +*/ + +#ifndef _CRYPTO_B128OPS_H +#define _CRYPTO_B128OPS_H + +#include + +typedef struct { + __be64 a, b; +} be128; + +typedef struct { + __le64 b, a; +} le128; + +static inline void be128_xor(be128 *r, const be128 *p, const be128 *q) +{ + r->a = p->a ^ q->a; + r->b = p->b ^ q->b; +} + +static inline void le128_xor(le128 *r, const le128 *p, const le128 *q) +{ + r->a = p->a ^ q->a; + r->b = p->b ^ q->b; +} + +#endif /* _CRYPTO_B128OPS_H */ -- cgit v1.3.1