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Date: Sun, 8 Sep 2019 23:19:54 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: =?iso-8859-1?Q?Micka=EBl_Sala=FCn?= <mic@digikod.net>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	=?iso-8859-1?Q?Micka=EBl_Sala=FCn?= <mickael.salaun@ssi.gouv.fr>,
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Subject: Re: [PATCH bpf-next v10 06/10] bpf,landlock: Add a new map type:
 inode
Message-ID: <20190908221954.GD1131@ZenIV.linux.org.uk>
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Sender: Al Viro <viro@ftp.linux.org.uk>

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();