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Subject: Re: HID: bpf: One function call less in call_hid_bpf_rdesc_fixup()
 after error detection
To: Hou Tao <houtao@huaweicloud.com>, bpf@vger.kernel.org,
 linux-input@vger.kernel.org, kernel-janitors@vger.kernel.org,
 Alexei Starovoitov <ast@kernel.org>,
 Benjamin Tissoires <benjamin.tissoires@redhat.com>,
 David Vernet <void@manifault.com>, Jiri Kosina <jikos@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>, cocci@inria.fr
References: <3203eb44-6e69-4bda-b585-426408cb75ee@web.de>
 <618f886f-b2ff-4d50-cf74-e8478a7e8547@huaweicloud.com>
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From: Markus Elfring <Markus.Elfring@web.de>
In-Reply-To: <618f886f-b2ff-4d50-cf74-e8478a7e8547@huaweicloud.com>
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>> The kfree() function was called in one case by the
>> call_hid_bpf_rdesc_fixup() function during error handling
>> even if the passed data structure member contained a null pointer.
>> This issue was detected by using the Coccinelle software.
>
> It is totally OK to free a null pointer through kfree() and the ENOMEM
> case is an unlikely case, so I don't think the patch is necessary.

Would you ever like to avoid redundant data processing a bit more?

Regards,
Markus