Re: Re: [PATCH] net: ieee802154: fix a null pointer in nl802154_trigger_scan

[慕冬亮 <dzm91@hust.edu.cn>]

> -----原始邮件-----
> 发件人: "Denis Kirjanov" <dkirjanov@suse.de>
> 发送时间: 2023-03-07 16:43:46 (星期二)
> 收件人: "Dongliang Mu" <dzm91@hust.edu.cn>, "Alexander Aring" <alex.aring@gmail.com>, "Stefan Schmidt" <stefan@datenfreihafen.org>, "Miquel Raynal" <miquel.raynal@bootlin.com>, "David S. Miller" <davem@davemloft.net>, "Eric Dumazet" <edumazet@google.com>, "Jakub Kicinski" <kuba@kernel.org>, "Paolo Abeni" <pabeni@redhat.com>
> 抄送: syzbot+bd85b31816913a32e473@syzkaller.appspotmail.com, linux-wpan@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org
> 主题: Re: [PATCH] net: ieee802154: fix a null pointer in nl802154_trigger_scan
> 
> 
> 
> 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.
> > 
> > Fix this by adding a null pointer check.
> > 
> > Reported-and-tested-by: syzbot+bd85b31816913a32e473@syzkaller.appspotmail.com
> > Signed-off-by: Dongliang Mu <dzm91@hust.edu.cn>
> 
> Please add a Fixes: tag 

I've sent a v2 patch. Thanks for your reminder.

> 
> > ---
> >  net/ieee802154/nl802154.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > 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;
> >  	}
> >  
> > -	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;
> >  	}