Date:   Tue, 7 Mar 2023 10:09:03 +0100
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Denis Kirjanov <dkirjanov@suse.de>
Cc:     Dongliang Mu <dzm91@hust.edu.cn>,
        Alexander Aring <alex.aring@gmail.com>,
        Stefan Schmidt <stefan@datenfreihafen.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        syzbot+bd85b31816913a32e473@syzkaller.appspotmail.com,
        linux-wpan@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: ieee802154: fix a null pointer in
 nl802154_trigger_scan
Message-ID: <20230307100903.71e2d9b2@xps-13>
In-Reply-To: <782a6f2d-84ae-3530-7e3c-07f31a4f303b@suse.de>
References: <20230307073004.74224-1-dzm91@hust.edu.cn>
        <782a6f2d-84ae-3530-7e3c-07f31a4f303b@suse.de>
Organization: Bootlin
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Hello,

dkirjanov@suse.de wrote on Tue, 7 Mar 2023 11:43:46 +0300:

> On 3/7/23 10:30, Dongliang Mu wrote:
> > There is a null pointer dereference if NL802154_ATTR_SCAN_TYPE is
> > not set by the user.
> >=20
> > Fix this by adding a null pointer check.

Thanks for the patch! This has been fixed already:
https://lore.kernel.org/linux-wpan/20230301154450.547716-1-miquel.raynal@bo=
otlin.com/T/#u

> > Reported-and-tested-by: syzbot+bd85b31816913a32e473@syzkaller.appspotma=
il.com

Just for reference, this tag shall not be used:

	"Please do not use combined tags, e.g.
	``Reported-and-tested-by``"
	Documentation/process/maintainer-tip.rst

> > Signed-off-by: Dongliang Mu <dzm91@hust.edu.cn> =20
>=20
> Please add a Fixes: tag=20
>=20
> > ---
> >  net/ieee802154/nl802154.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >=20
> > diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
> > index 2215f576ee37..1cf00cffd63f 100644
> > --- a/net/ieee802154/nl802154.c
> > +++ b/net/ieee802154/nl802154.c
> > @@ -1412,7 +1412,8 @@ static int nl802154_trigger_scan(struct sk_buff *=
skb, struct genl_info *info)
> >  		return -EOPNOTSUPP;
> >  	}
> > =20
> > -	if (!nla_get_u8(info->attrs[NL802154_ATTR_SCAN_TYPE])) {
> > +	if (!info->attrs[NL802154_ATTR_SCAN_TYPE] ||
> > +	    !nla_get_u8(info->attrs[NL802154_ATTR_SCAN_TYPE])) {
> >  		NL_SET_ERR_MSG(info->extack, "Malformed request, missing scan type");
> >  		return -EINVAL;
> >  	} =20


Thanks,
Miqu=C3=A8l