linux-kernel - Re: [PATCH] fs/9p: Improve exception handling in v9fs_session

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Date: Mon, 8 Jan 2024 20:09:30 +0900
From: Dominique Martinet <asmadeus@...ewreck.org>
To: Markus Elfring <Markus.Elfring@....de>
Cc: v9fs@...ts.linux.dev, kernel-janitors@...r.kernel.org,
	Christian Schönebeck <linux_oss@...debyte.com>,
	Eric Van Hensbergen <ericvh@...nel.org>,
	Latchesar Ionkov <lucho@...kov.net>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] fs/9p: Improve exception handling in v9fs_session_init()

Markus Elfring wrote on Thu, Dec 28, 2023 at 09:01:49PM +0100:
> The kfree() function was called in up to two cases by
> the v9fs_session_init() function during error handling
> even if the passed variable contained a null pointer.

I don't see the problem in calling kfree on null things (especially on
error path).

The only bad pattern I see here is that it relies on implicit
knowledge that aname is null before the call (which is true because
v9fs_session_init is only called immediately after kzalloc); is that
what your coccinelle script was checking for?

Anyway, as far as I'm concerned this is more churn than it's worth, but
I'll defer to Eric if he wants to take it.

Thanks,
-- 
Dominique