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/xattr.h | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 fs/gfs2/xattr.h (limited to 'fs/gfs2/xattr.h') diff --git a/fs/gfs2/xattr.h b/fs/gfs2/xattr.h new file mode 100644 index 000000000..3c9788e0e --- /dev/null +++ b/fs/gfs2/xattr.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. + */ + +#ifndef __EATTR_DOT_H__ +#define __EATTR_DOT_H__ + +struct gfs2_inode; +struct iattr; + +#define GFS2_EA_REC_LEN(ea) be32_to_cpu((ea)->ea_rec_len) +#define GFS2_EA_DATA_LEN(ea) be32_to_cpu((ea)->ea_data_len) + +#define GFS2_EA_SIZE(ea) \ +ALIGN(sizeof(struct gfs2_ea_header) + (ea)->ea_name_len + \ + ((GFS2_EA_IS_STUFFED(ea)) ? GFS2_EA_DATA_LEN(ea) : \ + (sizeof(__be64) * (ea)->ea_num_ptrs)), 8) + +#define GFS2_EA_IS_STUFFED(ea) (!(ea)->ea_num_ptrs) +#define GFS2_EA_IS_LAST(ea) ((ea)->ea_flags & GFS2_EAFLAG_LAST) + +#define GFS2_EAREQ_SIZE_STUFFED(er) \ +ALIGN(sizeof(struct gfs2_ea_header) + (er)->er_name_len + (er)->er_data_len, 8) + +#define GFS2_EA2NAME(ea) ((char *)((struct gfs2_ea_header *)(ea) + 1)) +#define GFS2_EA2DATA(ea) (GFS2_EA2NAME(ea) + (ea)->ea_name_len) + +#define GFS2_EA2DATAPTRS(ea) \ +((__be64 *)(GFS2_EA2NAME(ea) + ALIGN((ea)->ea_name_len, 8))) + +#define GFS2_EA2NEXT(ea) \ +((struct gfs2_ea_header *)((char *)(ea) + GFS2_EA_REC_LEN(ea))) + +#define GFS2_EA_BH2FIRST(bh) \ +((struct gfs2_ea_header *)((bh)->b_data + sizeof(struct gfs2_meta_header))) + +struct gfs2_ea_request { + const char *er_name; + char *er_data; + unsigned int er_name_len; + unsigned int er_data_len; + unsigned int er_type; /* GFS2_EATYPE_... */ +}; + +struct gfs2_ea_location { + struct buffer_head *el_bh; + struct gfs2_ea_header *el_ea; + struct gfs2_ea_header *el_prev; +}; + +int __gfs2_xattr_set(struct inode *inode, const char *name, + const void *value, size_t size, + int flags, int type); +ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size); +int gfs2_ea_dealloc(struct gfs2_inode *ip, bool initialized); + +/* Exported to acl.c */ + +int gfs2_xattr_acl_get(struct gfs2_inode *ip, const char *name, char **data); + +#endif /* __EATTR_DOT_H__ */ -- cgit v1.3.1