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Date: Wed, 1 Nov 2023 21:38:32 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Ren Mingshuai <renmingshuai@huawei.com>
Cc: <caowangbao@huawei.com>, <davem@davemloft.net>, <khlebnikov@openvz.org>,
 <liaichun@huawei.com>, <linux-kernel@vger.kernel.org>,
 <netdev@vger.kernel.org>, <oneukum@suse.com>, <yanan@huawei.com>
Subject: Re: [PATCH] net: usbnet: Fix potential NULL pointer dereference
Message-ID: <20231101213832.77bd657b@kernel.org>
In-Reply-To: <20231101125511.222629-1-renmingshuai@huawei.com>
References: <20231101123559.210756-1-renmingshuai@huawei.com>
	<20231101125511.222629-1-renmingshuai@huawei.com>
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On Wed, 1 Nov 2023 20:55:11 +0800 Ren Mingshuai wrote:
> >23ba07991dad said SKB can be NULL without describing the triggering
> >scenario. Always Check it before dereference to void potential NULL
> >pointer dereference.  
> I've tried to find out the scenarios where SKB is NULL, but failed.
> It seems impossible for SKB to be NULL. If SKB can be NULL, please tell
> me the reason and I'd be very grateful.

What do you mean? Grepping the function name shows call sites with NULL
getting passed as skb.