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 --- rust/uapi/lib.rs | 40 ++++++++++++++++++++++++++++++++++++++++ rust/uapi/uapi_helper.h | 16 ++++++++++++++++ 2 files changed, 56 insertions(+) create mode 100644 rust/uapi/lib.rs create mode 100644 rust/uapi/uapi_helper.h (limited to 'rust/uapi') diff --git a/rust/uapi/lib.rs b/rust/uapi/lib.rs new file mode 100644 index 000000000..797ead5b5 --- /dev/null +++ b/rust/uapi/lib.rs @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! UAPI Bindings. +//! +//! Contains the bindings generated by `bindgen` for UAPI interfaces. +//! +//! This crate may be used directly by drivers that need to interact with +//! userspace APIs. + +#![no_std] +#![allow( + clippy::all, + clippy::cast_lossless, + clippy::ptr_as_ptr, + clippy::ref_as_ptr, + clippy::undocumented_unsafe_blocks, + dead_code, + missing_docs, + non_camel_case_types, + non_upper_case_globals, + non_snake_case, + improper_ctypes, + unreachable_pub, + unsafe_op_in_unsafe_fn +)] +#![cfg_attr(CONFIG_RUSTC_HAS_UNNECESSARY_TRANSMUTES, allow(unnecessary_transmutes))] +#![cfg_attr( + CONFIG_RUSTC_HAS_SUSPICIOUS_RUNTIME_SYMBOL_DEFINITIONS, + allow(suspicious_runtime_symbol_definitions) +)] +#![feature(cfi_encoding)] + +// Manual definition of blocklisted types. +type __kernel_size_t = usize; +type __kernel_ssize_t = isize; +type __kernel_ptrdiff_t = isize; + +use pin_init::MaybeZeroable; + +include!(concat!(env!("OBJTREE"), "/rust/uapi/uapi_generated.rs")); diff --git a/rust/uapi/uapi_helper.h b/rust/uapi/uapi_helper.h new file mode 100644 index 000000000..1c4aa4292 --- /dev/null +++ b/rust/uapi/uapi_helper.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Header that contains the headers for which Rust UAPI bindings + * will be automatically generated by `bindgen`. + * + * Sorted alphabetically. + */ + +#include +#include +#include +#include +#include +#include +#include +#include -- cgit v1.3.1