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Date:   Tue, 13 Oct 2020 22:09:25 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Giuseppe Scrivano <gscrivan@redhat.com>
Cc:     linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        christian.brauner@ubuntu.com, containers@lists.linux-foundation.org
Subject: Re: [PATCH 1/2] fs, close_range: add flag CLOSE_RANGE_CLOEXEC
Message-ID: <20201013210925.GJ3576660@ZenIV.linux.org.uk>
References: <20201013140609.2269319-1-gscrivan@redhat.com>
 <20201013140609.2269319-2-gscrivan@redhat.com>
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On Tue, Oct 13, 2020 at 04:06:08PM +0200, Giuseppe Scrivano wrote:
> +		spin_lock(&cur_fds->file_lock);
> +		fdt = files_fdtable(cur_fds);
> +		cur_max = fdt->max_fds - 1;
> +		max_fd = min(max_fd, cur_max);
> +		while (fd <= max_fd)
> +			__set_close_on_exec(fd++, fdt);
> +		spin_unlock(&cur_fds->file_lock);

	First of all, this is an atrocious way to set all bits
in a range.  What's more, you don't want to set it for *all*
bits - only for the ones present in open bitmap.  It's probably
harmless at the moment, but let's not create interesting surprises
for the future.