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Date:   Mon, 14 Feb 2022 04:01:43 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Stefan Roesch <shr@fb.com>
Cc:     io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        kernel-team@fb.com
Subject: Re: [PATCH v1 1/2] fs: replace const char* parameter in vfs_statx
 and do_statx with struct filename
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References: <20220209190345.2374478-1-shr@fb.com>
 <20220209190345.2374478-2-shr@fb.com>
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On Wed, Feb 09, 2022 at 11:03:44AM -0800, Stefan Roesch wrote:
> +	int ret;
> +	int statx_flags = flags | AT_NO_AUTOMOUNT;
> +	struct filename *name;
> +
> +	name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL);
> +	ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS);
> +	if (name)
> +		putname(name);

1) getname and friends return an error as ERR_PTR(-E...), not NULL
2) filename_lookup() et.al. treat ERR_PTR(-E...) as "fail with -E..."
3) putname(ERR_PTR(-E...)) is a no-op.

IOW, that if (name) putname(name); is unidiomatic and misleading.