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/coda/Kconfig | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 fs/coda/Kconfig (limited to 'fs/coda/Kconfig') diff --git a/fs/coda/Kconfig b/fs/coda/Kconfig new file mode 100644 index 000000000..c3477eeaf --- /dev/null +++ b/fs/coda/Kconfig @@ -0,0 +1,22 @@ +# SPDX-License-Identifier: GPL-2.0-only +config CODA_FS + tristate "Coda file system support (advanced network fs)" + depends on INET + help + Coda is an advanced network file system, similar to NFS in that it + enables you to mount file systems of a remote server and access them + with regular Unix commands as if they were sitting on your hard + disk. Coda has several advantages over NFS: support for + disconnected operation (e.g. for laptops), read/write server + replication, security model for authentication and encryption, + persistent client caches and write back caching. + + If you say Y here, your Linux box will be able to act as a Coda + *client*. You will need user level code as well, both for the + client and server. Servers are currently user level, i.e. they need + no kernel support. Please read + and check out the Coda + home page . + + To compile the coda client support as a module, choose M here: the + module will be called coda. -- cgit v1.3.1