diff options
Diffstat (limited to 'kernel/bpf/bpf_iter.c')
-rw-r--r-- | kernel/bpf/bpf_iter.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c index 2726a5950cfa..5dc307bdeaeb 100644 --- a/kernel/bpf/bpf_iter.c +++ b/kernel/bpf/bpf_iter.c @@ -68,13 +68,18 @@ static void bpf_iter_done_stop(struct seq_file *seq) iter_priv->done_stop = true; } +static inline bool bpf_iter_target_support_resched(const struct bpf_iter_target_info *tinfo) +{ + return tinfo->reg_info->feature & BPF_ITER_RESCHED; +} + static bool bpf_iter_support_resched(struct seq_file *seq) { struct bpf_iter_priv_data *iter_priv; iter_priv = container_of(seq->private, struct bpf_iter_priv_data, target_private); - return iter_priv->tinfo->reg_info->feature & BPF_ITER_RESCHED; + return bpf_iter_target_support_resched(iter_priv->tinfo); } /* maximum visited objects before bailing out */ @@ -197,6 +202,11 @@ static ssize_t bpf_seq_read(struct file *file, char __user *buf, size_t size, } stop: offs = seq->count; + if (IS_ERR(p)) { + seq->op->stop(seq, NULL); + err = PTR_ERR(p); + goto done; + } /* bpf program called if !p */ seq->op->stop(seq, p); if (!p) { @@ -537,6 +547,10 @@ int bpf_iter_link_attach(const union bpf_attr *attr, bpfptr_t uattr, if (!tinfo) return -ENOENT; + /* Only allow sleepable program for resched-able iterator */ + if (prog->aux->sleepable && !bpf_iter_target_support_resched(tinfo)) + return -EINVAL; + link = kzalloc(sizeof(*link), GFP_USER | __GFP_NOWARN); if (!link) return -ENOMEM; @@ -680,19 +694,24 @@ struct bpf_prog *bpf_iter_get_info(struct bpf_iter_meta *meta, bool in_stop) int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx) { + struct bpf_run_ctx run_ctx, *old_run_ctx; int ret; if (prog->aux->sleepable) { rcu_read_lock_trace(); migrate_disable(); might_fault(); + old_run_ctx = bpf_set_run_ctx(&run_ctx); ret = bpf_prog_run(prog, ctx); + bpf_reset_run_ctx(old_run_ctx); migrate_enable(); rcu_read_unlock_trace(); } else { rcu_read_lock(); migrate_disable(); + old_run_ctx = bpf_set_run_ctx(&run_ctx); ret = bpf_prog_run(prog, ctx); + bpf_reset_run_ctx(old_run_ctx); migrate_enable(); rcu_read_unlock(); } |