2023-09-01 08:10:01

by shaozhengchao

[permalink] [raw]
Subject: Re: [PATCH net,v2] wifi: mac80211: fix WARNING in ieee80211_link_info_change_notify()



On 2023/9/1 12:38, Kalle Valo wrote:
> Zhengchao Shao <[email protected]> writes:
>
>> Syz reports the following WARNING:
>> wlan0: Failed check-sdata-in-driver check, flags: 0x0
>> WARNING: CPU: 3 PID: 5384 at net/mac80211/main.c:287
>> ieee80211_link_info_change_notify+0x1c2/0x230
>> Modules linked in:
>> RIP: 0010:ieee80211_link_info_change_notify+0x1c2/0x230
>> Call Trace:
>> <TASK>
>> ieee80211_set_mcast_rate+0x3e/0x50
>> nl80211_set_mcast_rate+0x316/0x650
>> genl_family_rcv_msg_doit+0x20b/0x300
>> genl_rcv_msg+0x39f/0x6a0
>> netlink_rcv_skb+0x13b/0x3b0
>> genl_rcv+0x24/0x40
>> netlink_unicast+0x4a2/0x740
>> netlink_sendmsg+0x83e/0xce0
>> sock_sendmsg+0xc5/0x100
>> ____sys_sendmsg+0x583/0x690
>> ___sys_sendmsg+0xe8/0x160
>> __sys_sendmsg+0xbf/0x160
>> do_syscall_64+0x35/0x80
>> entry_SYSCALL_64_after_hwframe+0x46/0xb0
>> </TASK>
>>
>> The execution process is as follows:
>> Thread A:
>> ieee80211_open()
>> ieee80211_do_open()
>> drv_add_interface() //set IEEE80211_SDATA_IN_DRIVER flag
>> ...
>> rtnl_newlink
>> do_setlink
>> dev_change_flags
>> ...
>> __dev_close_many
>> ieee80211_stop()
>> ieee80211_do_stop()
>> drv_remove_interface() //clear flag
>> ...
>> nl80211_set_mcast_rate()
>> ieee80211_set_mcast_rate()
>> ieee80211_link_info_change_notify()
>> check_sdata_in_driver() //WARNING because flag is cleared
>>
>> When the wlan device stops, the IEEE80211_SDATA_IN_ DRIVER flag is cleared.
>> And then after the set mcast rate command is executed, WARNING is generated
>> because the flag bit has been already cleared.
>>
>> Fixes: 591e73ee3f73 ("wifi: mac80211: properly skip link info driver update")
>> Reported-by: [email protected]
>> Signed-off-by: Zhengchao Shao <[email protected]>
>
> Wireless patches (ie. anything which starts with "wifi:") go to wireless
> and wireless-next trees, not to net tree.
>
Thank you for your reminder. I'll pay attention next time.

Zhengchao Shao