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Date:   Thu, 29 Dec 2022 17:18:16 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jisoo Jang <jisoo.jang@yonsei.ac.kr>
Cc:     linux-wireless@vger.kernel.org, linuxlovemin@yonsei.ac.kr,
        dokyungs@yonsei.ac.kr
Subject: Re: [PATCH] wifi: mt7601u: fix an integer underflow
Message-ID: <20221229171816.42022e23@kernel.org>
In-Reply-To: <20221229092906.2328282-1-jisoo.jang@yonsei.ac.kr>
References: <20221229092906.2328282-1-jisoo.jang@yonsei.ac.kr>
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On Thu, 29 Dec 2022 18:29:06 +0900 Jisoo Jang wrote:
> Fix an integer underflow that leads to a null pointer dereference in
> 'mt7601u_rx_skb_from_seg()'. The variable 'dma_len' in the URB packet
> could be manipulated, which could trigger an integer underflow of
> 'seg_len' in 'mt7601u_rx_process_seg()'. This underflow subsequently
> causes the 'bad_frame' checks in 'mt7601u_rx_skb_from_seg()' to be
> bypassed, eventually leading to a dereference of the pointer 'p', which
> is a null pointer.
> 
> Ensure that 'dma_len' is greater than 'min_seg_len'.

Acked-by: Jakub Kicinski <kuba@kernel.org>