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/fuse/args.h | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 fs/fuse/args.h (limited to 'fs/fuse/args.h') diff --git a/fs/fuse/args.h b/fs/fuse/args.h new file mode 100644 index 000000000..ecfe51a19 --- /dev/null +++ b/fs/fuse/args.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _FS_FUSE_ARGS_H +#define _FS_FUSE_ARGS_H + +#include + +struct fuse_mount; + +/** One input argument of a request */ +struct fuse_in_arg { + unsigned size; + const void *value; +}; + +/** One output argument of a request */ +struct fuse_arg { + unsigned size; + void *value; +}; + +struct fuse_args { + u64 nodeid; + u32 opcode; + u32 uid; + u32 gid; + u32 pid; + u8 in_numargs; + u8 out_numargs; + u8 ext_idx; + bool force:1; + bool noreply:1; + bool nocreds:1; + bool in_pages:1; + bool out_pages:1; + bool user_pages:1; + bool out_argvar:1; + bool page_zeroing:1; + bool page_replace:1; + bool may_block:1; + bool is_ext:1; + bool is_pinned:1; + bool invalidate_vmap:1; + bool abort_on_kill:1; + struct fuse_in_arg in_args[4]; + struct fuse_arg out_args[2]; + void (*end)(struct fuse_args *args, int error); + /* Used for kvec iter backed by vmalloc address */ + void *vmap_base; +}; + +/** FUSE folio descriptor */ +struct fuse_folio_desc { + unsigned int length; + unsigned int offset; +}; + +struct fuse_args_pages { + struct fuse_args args; + struct folio **folios; + struct fuse_folio_desc *descs; + unsigned int num_folios; +}; + +#endif /* _FS_FUSE_ARGS_H */ -- cgit v1.3.1