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/smb/server/ndr.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 fs/smb/server/ndr.h (limited to 'fs/smb/server/ndr.h') diff --git a/fs/smb/server/ndr.h b/fs/smb/server/ndr.h new file mode 100644 index 000000000..f3c108c8c --- /dev/null +++ b/fs/smb/server/ndr.h @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2020 Samsung Electronics Co., Ltd. + * Author(s): Namjae Jeon + */ + +struct ndr { + char *data; + int offset; + int length; +}; + +#define NDR_NTSD_OFFSETOF 0xA0 + +int ndr_encode_dos_attr(struct ndr *n, struct xattr_dos_attrib *da); +int ndr_decode_dos_attr(struct ndr *n, struct xattr_dos_attrib *da); +int ndr_encode_posix_acl(struct ndr *n, struct mnt_idmap *idmap, + struct inode *inode, struct xattr_smb_acl *acl, + struct xattr_smb_acl *def_acl); +int ndr_encode_v4_ntacl(struct ndr *n, struct xattr_ntacl *acl); +int ndr_encode_v3_ntacl(struct ndr *n, struct xattr_ntacl *acl); +int ndr_decode_v4_ntacl(struct ndr *n, struct xattr_ntacl *acl); -- cgit v1.3.1