Re: [PATCH V3 2/9] mac80211: add multiple bssid support to interface handling

Pradeep Kumar Chitrapu
2020-10-08T17:21:33Z

On 2020-10-08 01:06, John Crispin wrote:
> On 08.10.20 02:33, Pradeep Kumar Chitrapu wrote:
>>>
>>>  static int ieee80211_del_iface(struct wiphy *wiphy, struct
>>> wireless_dev *wdev)
>>>  {
>>> +    struct ieee80211_sub_if_data *sdata;
>>> +    struct ieee80211_vif *child, *tmp;
>>> +
>>> +    sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
>>> +    if (sdata->vif.type == NL80211_IFTYPE_AP) {
>> Hi John, Observed a NULL ptr dereference error here..
>>
>> Thanks
>> Pradeep
>
>
> how did you trigger it ?
>
>     John
Hi

Deleted the interface and did rmmod and insmod of cfg80211/mac80211/ath
modules.

[ 883.565933] Unable to handle kernel NULL pointer dereference at
virtual address 00000000
[ 883.565970] pgd = b311c000
[ 883.573357] [00000000] *pgd=00000000
[ 883.579021] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[ 883.848257] task: bd1ac600 ti: b027a000 task.ti: b027a000
[ 883.852904] PC is at ieee80211_del_iface+0x34/0x90 [mac80211]
[ 883.858333] LR is at extack_doit+0x20/0x6c [compat]
[ 884.092936] [<c751fbd8>] (ieee80211_del_iface [mac80211]) from
[<7f56181c>] (extack_doit+0x20/0x6c [compat])
[ 884.100991] [<7f56181c>] (extack_doit [compat]) from [<8076a340>]
(genl_rcv_msg+0x27c/0x300)
[ 884.110854] [<8076a340>] (genl_rcv_msg) from [<807696c0>]
(netlink_rcv_skb+0x58/0xb4)

Thanks
Pradeep