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Message-ID: <7a67262f-c824-df23-40dd-2e54041f3ec3@canonical.com>
Date:   Sat, 6 Nov 2021 10:42:06 +0100
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Subject: Re: [PATCH v2] nfc: pn533: Fix double free when
 pn533_fill_fragment_skbs() fails
Content-Language: en-US
To:     Chengfeng Ye <cyeaa@connect.ust.hk>, davem@davemloft.net,
        kuba@kernel.org, wengjianfeng@yulong.com, dan.carpenter@oracle.com
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20211105133636.31282-1-cyeaa@connect.ust.hk>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
In-Reply-To: <20211105133636.31282-1-cyeaa@connect.ust.hk>
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Precedence: bulk

On 05/11/2021 14:36, Chengfeng Ye wrote:
> skb is already freed by dev_kfree_skb in pn533_fill_fragment_skbs,
> but follow error handler branch when pn533_fill_fragment_skbs()
> fails, skb is freed again, results in double free issue. Fix this
> by not free skb in error path of pn533_fill_fragment_skbs.
> 
> Signed-off-by: Chengfeng Ye <cyeaa@connect.ust.hk>
> ---
>  drivers/nfc/pn533/pn533.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Looks good, thanks:
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

Please do not forget about fixes tag. Here it is trickier because
pn533_fill_fragment_skbs() usage was introduced in two commits:

Fixes: 963a82e07d4e ("NFC: pn533: Split large Tx frames in chunks")
Fixes: 93ad42020c2d ("NFC: pn533: Target mode Tx fragmentation support")
Cc: <stable@vger.kernel.org>

Best regards,
Krzysztof