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/9p/acl.h | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 fs/9p/acl.h (limited to 'fs/9p/acl.h') diff --git a/fs/9p/acl.h b/fs/9p/acl.h new file mode 100644 index 000000000..333cfcc28 --- /dev/null +++ b/fs/9p/acl.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: LGPL-2.1 */ +/* + * Copyright IBM Corporation, 2010 + * Author Aneesh Kumar K.V + */ +#ifndef FS_9P_ACL_H +#define FS_9P_ACL_H + +#ifdef CONFIG_9P_FS_POSIX_ACL +int v9fs_get_acl(struct inode *inode, struct p9_fid *fid); +struct posix_acl *v9fs_iop_get_inode_acl(struct inode *inode, int type, + bool rcu); +struct posix_acl *v9fs_iop_get_acl(struct mnt_idmap *idmap, + struct dentry *dentry, int type); +int v9fs_iop_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, + struct posix_acl *acl, int type); +int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid); +int v9fs_set_create_acl(struct inode *inode, struct p9_fid *fid, + struct posix_acl *dacl, struct posix_acl *acl); +int v9fs_acl_mode(struct inode *dir, umode_t *modep, + struct posix_acl **dpacl, struct posix_acl **pacl); +void v9fs_put_acl(struct posix_acl *dacl, struct posix_acl *acl); +#else +#define v9fs_iop_get_inode_acl NULL +#define v9fs_iop_get_acl NULL +#define v9fs_iop_set_acl NULL +static inline int v9fs_get_acl(struct inode *inode, struct p9_fid *fid) +{ + return 0; +} +static inline int v9fs_acl_chmod(struct inode *inode, struct p9_fid *fid) +{ + return 0; +} +static inline int v9fs_set_create_acl(struct inode *inode, + struct p9_fid *fid, + struct posix_acl *dacl, + struct posix_acl *acl) +{ + return 0; +} +static inline void v9fs_put_acl(struct posix_acl *dacl, + struct posix_acl *acl) +{ +} +static inline int v9fs_acl_mode(struct inode *dir, umode_t *modep, + struct posix_acl **dpacl, + struct posix_acl **pacl) +{ + return 0; +} + +#endif +#endif /* FS_9P_XATTR_H */ -- cgit v1.3.1