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 --- io_uring/timeout.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 io_uring/timeout.h (limited to 'io_uring/timeout.h') diff --git a/io_uring/timeout.h b/io_uring/timeout.h new file mode 100644 index 000000000..1620f94dd --- /dev/null +++ b/io_uring/timeout.h @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 + +struct io_timeout_data { + struct io_kiocb *req; + struct hrtimer timer; + ktime_t time; + enum hrtimer_mode mode; + u32 flags; +}; + +__cold void io_flush_timeouts(struct io_ring_ctx *ctx); +struct io_cancel_data; +int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd); +__cold bool io_kill_timeouts(struct io_ring_ctx *ctx, struct io_uring_task *tctx, + bool cancel_all); +void io_queue_linked_timeout(struct io_kiocb *req); +void io_disarm_next(struct io_kiocb *req); + +int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_link_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_timeout(struct io_kiocb *req, unsigned int issue_flags); +int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags); -- cgit v1.3.1