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/nfsd/stats.h | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 fs/nfsd/stats.h (limited to 'fs/nfsd/stats.h') diff --git a/fs/nfsd/stats.h b/fs/nfsd/stats.h new file mode 100644 index 000000000..e4efb0e4e --- /dev/null +++ b/fs/nfsd/stats.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Statistics for NFS server. + * + * Copyright (C) 1995, 1996 Olaf Kirch + */ +#ifndef _NFSD_STATS_H +#define _NFSD_STATS_H + +#include +#include + +struct proc_dir_entry *nfsd_proc_stat_init(struct net *net); +void nfsd_proc_stat_shutdown(struct net *net); + +static inline void nfsd_stats_rc_hits_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_RC_HITS]); +} + +static inline void nfsd_stats_rc_misses_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_RC_MISSES]); +} + +static inline void nfsd_stats_rc_nocache_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_RC_NOCACHE]); +} + +static inline void nfsd_stats_fh_stale_inc(struct nfsd_net *nn, + struct svc_export *exp) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_FH_STALE]); + if (exp && exp->ex_stats) + percpu_counter_inc(&exp->ex_stats->counter[EXP_STATS_FH_STALE]); +} + +static inline void nfsd_stats_io_read_add(struct nfsd_net *nn, + struct svc_export *exp, s64 amount) +{ + percpu_counter_add(&nn->counter[NFSD_STATS_IO_READ], amount); + if (exp && exp->ex_stats) + percpu_counter_add(&exp->ex_stats->counter[EXP_STATS_IO_READ], amount); +} + +static inline void nfsd_stats_io_write_add(struct nfsd_net *nn, + struct svc_export *exp, s64 amount) +{ + percpu_counter_add(&nn->counter[NFSD_STATS_IO_WRITE], amount); + if (exp && exp->ex_stats) + percpu_counter_add(&exp->ex_stats->counter[EXP_STATS_IO_WRITE], amount); +} + +static inline void nfsd_stats_payload_misses_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_PAYLOAD_MISSES]); +} + +static inline void nfsd_stats_drc_mem_usage_add(struct nfsd_net *nn, s64 amount) +{ + percpu_counter_add(&nn->counter[NFSD_STATS_DRC_MEM_USAGE], amount); +} + +static inline void nfsd_stats_drc_mem_usage_sub(struct nfsd_net *nn, s64 amount) +{ + percpu_counter_sub(&nn->counter[NFSD_STATS_DRC_MEM_USAGE], amount); +} + +#ifdef CONFIG_NFSD_V4 +static inline void nfsd_stats_wdeleg_getattr_inc(struct nfsd_net *nn) +{ + percpu_counter_inc(&nn->counter[NFSD_STATS_WDELEG_GETATTR]); +} +#endif +#endif /* _NFSD_STATS_H */ -- cgit v1.3.1