Re: [PATCH bpf-next v10 06/10] bpf,landlock: Add a new map type: inode

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

On Mon, Sep 09, 2019 at 12:09:57AM +0200, Mickaël Salaün wrote:

> >>> +    rcu_read_lock();
> >>> +    ptr = htab_map_lookup_elem(map, &inode);
> >>> +    iput(inode);

Wait a sec.  You are doing _what_ under rcu_read_lock()?

> >>> +    if (IS_ERR(ptr)) {
> >>> +            ret = PTR_ERR(ptr);
> >>> +    } else if (!ptr) {
> >>> +            ret = -ENOENT;
> >>> +    } else {
> >>> +            ret = 0;
> >>> +            copy_map_value(map, value, ptr);
> >>> +    }
> >>> +    rcu_read_unlock();