On Tue, Aug 09, 2022 at 07:02:45PM +0300, Viacheslav Sablin wrote:
From: Ahmed Zaki anzaki@gmail.com
commit 8f9dcc29566626f683843ccac6113a12208315ca upstream.
The following is from a system that went OOM due to a memory leak:
wlan0: Allocated STA 74:83:c2:64:0b:87 wlan0: Allocated STA 74:83:c2:64:0b:87 wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_add_sta) wlan0: Adding new IBSS station 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 3 wlan0: Inserted STA 74:83:c2:64:0b:87 wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_work) wlan0: Adding new IBSS station 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 3 . . wlan0: expiring inactive not authorized STA 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 1 wlan0: Removed STA 74:83:c2:64:0b:87 wlan0: Destroyed STA 74:83:c2:64:0b:87
The ieee80211_ibss_finish_sta() is called twice on the same STA from 2 different locations. On the second attempt, the allocated STA is not destroyed creating a kernel memory leak.
This is happening because sta_info_insert_finish() does not call sta_info_free() the second time when the STA already exists (returns -EEXIST). Note that the caller sta_info_insert_rcu() assumes STA is destroyed upon errors.
Same fix is applied to -ENOMEM.
Signed-off-by: Ahmed Zaki anzaki@gmail.com Link: https://lore.kernel.org/r/20211002145329.3125293-1-anzaki@gmail.com [change the error path label to use the existing code] Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Viacheslav Sablin sablin@ispras.ru
net/mac80211/sta_info.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
This is also needed in 5.15.y, so added there as well. thanks,
greg k-h