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 --- fs/notify/inotify/Kconfig | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 fs/notify/inotify/Kconfig (limited to 'fs/notify/inotify/Kconfig') diff --git a/fs/notify/inotify/Kconfig b/fs/notify/inotify/Kconfig new file mode 100644 index 000000000..1cc8be25d --- /dev/null +++ b/fs/notify/inotify/Kconfig @@ -0,0 +1,17 @@ +# SPDX-License-Identifier: GPL-2.0-only +config INOTIFY_USER + bool "Inotify support for userspace" + select FSNOTIFY + default y + help + Say Y here to enable inotify support for userspace, including the + associated system calls. Inotify allows monitoring of both files and + directories via a single open fd. Events are read from the file + descriptor, which is also select()- and poll()-able. + Inotify fixes numerous shortcomings in dnotify and introduces several + new features including multiple file events, one-shot support, and + unmount notification. + + For more information, see + + If unsure, say Y. -- cgit v1.3.1