Hi 慕冬亮, dzm91@xxxxxxxxxxx wrote on Tue, 7 Mar 2023 17:21:49 +0800 (GMT+08:00): > > -----原始邮件----- > > 发件人: "Miquel Raynal" <miquel.raynal@xxxxxxxxxxx> > > 发送时间: 2023-03-07 17:09:03 (星期二) > > 收件人: "Denis Kirjanov" <dkirjanov@xxxxxxx> > > 抄送: "Dongliang Mu" <dzm91@xxxxxxxxxxx>, "Alexander Aring" <alex.aring@xxxxxxxxx>, "Stefan Schmidt" <stefan@xxxxxxxxxxxxxxxxxx>, "David > > S. Miller" <davem@xxxxxxxxxxxxx>, "Eric Dumazet" <edumazet@xxxxxxxxxx>, "Jakub > > Kicinski" <kuba@xxxxxxxxxx>, "Paolo Abeni" <pabeni@xxxxxxxxxx>, syzbot+bd85b31816913a32e473@xxxxxxxxxxxxxxxxxxxxxxxxx, linux-wpan@xxxxxxxxxxxxxxx, netdev@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx > > 主题: Re: [PATCH] net: ieee802154: fix a null pointer in nl802154_trigger_scan > > > > Hello, > > > > dkirjanov@xxxxxxx 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. > > > > > > > > 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@xxxxxxxxxxx/T/#u > > Oh, I see. Thanks for your reply. > > A small issue: should we still check !nla_get_u8(info->attrs[NL802154_ATTR_SCAN_TYPE])? Isn't it already handled? There is a switch case over it with a default statement to handle unsupported scan types. > > > > Reported-and-tested-by: syzbot+bd85b31816913a32e473@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > 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 > > > > Okay. This is suggested by Syzbot. I will use separate tags in the future. > > > > > Signed-off-by: Dongliang Mu <dzm91@xxxxxxxxxxx> > > > > > > Please add a Fixes: tag > > > > > > > --- > > > > 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; > > > > } > > > > > > Thanks, > > Miquèl > > > -- > Best regards, > Dongliang Mu Thanks, Miquèl
