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Date: Tue, 10 Mar 2026 17:48:41 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Guoyu Su <yss2813483011xxl@gmail.com>
Cc: edumazet@google.com, davem@davemloft.net, pabeni@redhat.com,
 netdev@vger.kernel.org, horms@kernel.org, linux-kernel@vger.kernel.org,
 syzkaller-bugs@googlegroups.com,
 syzbot+1543a7d954d9c6d00407@syzkaller.appspotmail.com
Subject: Re: [PATCH net v2] net: use skb_header_pointer() in
 gso_features_check() for TCPv4 GSO
Message-ID: <20260310174841.5f5671c5@kernel.org>
In-Reply-To: <20260308083319.1255118-1-yss2813483011xxl@gmail.com>
References: <20260307162905.3697050-1-yss2813483011xxl@gmail.com>
	<20260308083319.1255118-1-yss2813483011xxl@gmail.com>
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On Sun,  8 Mar 2026 16:33:19 +0800 Guoyu Su wrote:
>  - Drop the SKB_GSO_DODGY shortcut.
>  - Use skb_header_pointer() for safe IPv4 header access.

Let's keep the DODGY check and directly compare skb->len to offset +
sizeof(*ip)? Some of the callers in the syz repro are probably buggy
(HSR?) so they should be fixed rather than ignored.