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/gfs2/Kconfig | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 fs/gfs2/Kconfig (limited to 'fs/gfs2/Kconfig') diff --git a/fs/gfs2/Kconfig b/fs/gfs2/Kconfig new file mode 100644 index 000000000..8beee571b --- /dev/null +++ b/fs/gfs2/Kconfig @@ -0,0 +1,36 @@ +# SPDX-License-Identifier: GPL-2.0-only +config GFS2_FS + tristate "GFS2 file system support" + select BUFFER_HEAD + select FS_POSIX_ACL + select CRC32 + select QUOTACTL + select FS_IOMAP + help + A cluster filesystem. + + Allows a cluster of computers to simultaneously use a block device + that is shared between them (with FC, iSCSI, NBD, etc...). GFS reads + and writes to the block device like a local filesystem, but also uses + a lock module to allow the computers coordinate their I/O so + filesystem consistency is maintained. One of the nifty features of + GFS is perfect consistency -- changes made to the filesystem on one + machine show up immediately on all other machines in the cluster. + + To use the GFS2 filesystem in a cluster, you will need to enable + the locking module below. Documentation and utilities for GFS2 can + be found here: http://sources.redhat.com/cluster + + The "nolock" lock module is now built in to GFS2 by default. If + you want to use the DLM, be sure to enable IPv4/6 networking. + +config GFS2_FS_LOCKING_DLM + bool "GFS2 DLM locking" + depends on (GFS2_FS!=n) && NET && INET && \ + CONFIGFS_FS && SYSFS && (DLM=y || DLM=GFS2_FS) + help + Multiple node locking module for GFS2 + + Most users of GFS2 will require this. It provides the locking + interface between GFS2 and the DLM, which is required to use GFS2 + in a cluster environment. -- cgit v1.3.1