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Date: Wed, 16 Sep 2026 16:08:46 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Emil Tsalapatis <emil@etsalapatis.com>
Cc: bpf@vger.kernel.org, ast@kernel.org, andrii@kernel.org,
 eddyz87@gmail.com, memxor@gmail.com, daniel@iogearbox.net,
 netdev@vger.kernel.org, Nicholas Carlini <nicholas@carlini.com>
Subject: Re: [PATCH bpf 01/11] bpf: Fix bounds check for skb-backed dynptrs
Message-ID: <20260916160846.557e2ee9@kernel.org>
In-Reply-To: <20260916050830.8774-2-emil@etsalapatis.com>
References: <20260916050830.8774-1-emil@etsalapatis.com>
	<20260916050830.8774-2-emil@etsalapatis.com>
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On Wed, 16 Sep 2026 05:08:19 +0000 Emil Tsalapatis wrote:
> -	if (likely(skb_headlen(skb) - offset >= len))
> +	if (likely((u64)offset <= skb_headlen(skb) && 
> +			(u64)len <= skb_headlen(skb) - (u64)offset))

I don't think the 64b arithmetic is needed since the max value
(headlen) itself is 32b. You can cast to unsigned int.

Also the continuation line is mis-aligned