Date:   Mon, 27 Feb 2023 15:06:58 +0100
From:   Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
To:     void0red <void0red@gmail.com>
Cc:     angelogioacchino.delregno@collabora.com, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, kvalo@kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-mediatek@lists.infradead.org, linux-wireless@vger.kernel.org,
        lorenzo@kernel.org, matthias.bgg@gmail.com, nbd@nbd.name,
        netdev@vger.kernel.org, pabeni@redhat.com, ryder.lee@mediatek.com,
        sean.wang@mediatek.com, shayne.chen@mediatek.com
Subject: Re: [PATCH v2] wifi: mt76: add a check of vzalloc in
 mt7615_coredump_work
Message-ID: <Y/y5Asxw3T3m4jCw@lore-desk>
References: <Y/yxGMvBbMGiehC6@lore-desk>
 <20230227135241.947052-1-void0red@gmail.com>
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> From: Kang Chen <void0red@gmail.com>
>=20
> vzalloc may fails, dump might be null and will cause
> illegal address access later.
>=20
> Fixes: d2bf7959d9c0 ("mt76: mt7663: introduce coredump support")
> Signed-off-by: Kang Chen <void0red@gmail.com>
> ---
> v2 -> v1: add Fixes tag
>=20
>  drivers/net/wireless/mediatek/mt76/mt7615/mac.c | 3 +++
>  1 file changed, 3 insertions(+)
>=20
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c b/drivers/ne=
t/wireless/mediatek/mt76/mt7615/mac.c
> index a95602473..73d84c301 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
> @@ -2367,6 +2367,9 @@ void mt7615_coredump_work(struct work_struct *work)
>  	}
> =20
>  	dump =3D vzalloc(MT76_CONNAC_COREDUMP_SZ);
> +	if (!dump)
> +		return;
> +
>  	data =3D dump;
> =20
>  	while (true) {
> --=20
> 2.34.1
>=20

revieweing the code I guess the right approach would be the one used in
mt7921_coredump_work():
- free pending skbs
- not run dev_coredumpv()

What do you think?

Regards,
Lorenzo

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