[ Upstream commit 46ba53c306 ]
When executing SMP task failed, the smp_execute_task_sg() calls del_timer()
to delete "slow_task->timer". However, if the timer handler
sas_task_internal_timedout() is running, the del_timer() in
smp_execute_task_sg() will not stop it and a UAF will happen. The process
is shown below:
(thread 1) | (thread 2)
smp_execute_task_sg() | sas_task_internal_timedout()
... |
del_timer() |
... | ...
sas_free_task(task) |
kfree(task->slow_task) //FREE|
| task->slow_task->... //USE
Fix by calling del_timer_sync() in smp_execute_task_sg(), which makes sure
the timer handler have finished before the "task->slow_task" is
deallocated.
Link: https://lore.kernel.org/r/20220920144213.10536-1-duoming@zju.edu.cn
Fixes: 2908d778ab ("[SCSI] aic94xx: new driver")
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
e45a1516d2