On 2/17/21 11:23 PM, Kalle Valo wrote:
Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:This reverts commit a56c14bb21b296fb6d395164ab62ef2e419e5069. ath_tx_process_buffer() doesn't dereference or check sta and passes it to ath_tx_complete_aggr() and ath_tx_complete_buf(). ath_tx_complete_aggr() checks the pointer before use. No problem here. ath_tx_complete_buf() doesn't check or dereference sta and passes it on to ath_tx_complete(). ath_tx_complete() doesn't check or dereference sta, but assigns it to tx_info->status.status_driver_data[0] ath_tx_complete_buf() is called from ath_tx_complete_aggr() passing null ieee80211_sta pointer. There is a potential for dereference later on, if and when the tx_info->status.status_driver_data[0]is referenced. In addition, the rcu read lock might be released before referencing the contents. ath_tx_complete_buf() should be fixed to check sta perhaps? Worth looking into. Reverting this patch because it doesn't solve the problem and introduces memory leak by skipping buffer completion if the pointer (sta) is NULL. Fixes: a56c14bb21b2 ("ath9k: fix ath_tx_process_buffer() potential null ptr dereference") Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>Thanks. I added the commit id and Fixes tag to the commit log, see the new version above.
Thanks. Sorry for forgetting the Fixes tag. thanks, -- Shuah
