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 --- scripts/kconfig/mnconf-common.c | 53 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 scripts/kconfig/mnconf-common.c (limited to 'scripts/kconfig/mnconf-common.c') diff --git a/scripts/kconfig/mnconf-common.c b/scripts/kconfig/mnconf-common.c new file mode 100644 index 000000000..8e24b0712 --- /dev/null +++ b/scripts/kconfig/mnconf-common.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include "expr.h" +#include "mnconf-common.h" + +int jump_key_char; + +int next_jump_key(int key) +{ + if (key < '1' || key > '9') + return '1'; + + key++; + + if (key > '9') + key = '1'; + + return key; +} + +int handle_search_keys(int key, size_t start, size_t end, void *_data) +{ + struct search_data *data = _data; + struct jump_key *pos; + int index = 0; + + if (key < '1' || key > '9') + return 0; + + list_for_each_entry(pos, data->head, entries) { + index = next_jump_key(index); + + if (pos->offset < start) + continue; + + if (pos->offset >= end) + break; + + if (key == index) { + data->target = pos->target; + return 1; + } + } + + return 0; +} + +int get_jump_key_char(void) +{ + jump_key_char = next_jump_key(jump_key_char); + + return jump_key_char; +} -- cgit v1.3.1