From: Igor Pylypiv ipylypiv@google.com
[ Upstream commit d712d3fb484b7fa8d1d57e9ca6f134bb9d8c18b1 ]
The TMF timeout timer may trigger at the same time when the response from a controller is being handled. When this happens the SAS task may get freed before the response processing is finished.
Fix this by calling complete() only when SAS_TASK_STATE_DONE is not set.
A similar race condition was fixed in commit b90cd6f2b905 ("scsi: libsas: fix a race condition when smp task timeout")
Link: https://lore.kernel.org/r/20210707185945.35559-1-ipylypiv@google.com Reviewed-by: Vishakha Channapattan vishakhavc@google.com Acked-by: Jack Wang jinpu.wang@ionos.com Signed-off-by: Igor Pylypiv ipylypiv@google.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/pm8001/pm8001_sas.c | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-)
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c index 39de9a9360d3..c3bb58885033 100644 --- a/drivers/scsi/pm8001/pm8001_sas.c +++ b/drivers/scsi/pm8001/pm8001_sas.c @@ -684,8 +684,7 @@ int pm8001_dev_found(struct domain_device *dev)
void pm8001_task_done(struct sas_task *task) { - if (!del_timer(&task->slow_task->timer)) - return; + del_timer(&task->slow_task->timer); complete(&task->slow_task->completion); }
@@ -693,9 +692,14 @@ static void pm8001_tmf_timedout(struct timer_list *t) { struct sas_task_slow *slow = from_timer(slow, t, timer); struct sas_task *task = slow->task; + unsigned long flags;
- task->task_state_flags |= SAS_TASK_STATE_ABORTED; - complete(&task->slow_task->completion); + spin_lock_irqsave(&task->task_state_lock, flags); + if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) { + task->task_state_flags |= SAS_TASK_STATE_ABORTED; + complete(&task->slow_task->completion); + } + spin_unlock_irqrestore(&task->task_state_lock, flags); }
#define PM8001_TASK_TIMEOUT 20 @@ -748,13 +752,10 @@ static int pm8001_exec_internal_tmf_task(struct domain_device *dev, } res = -TMF_RESP_FUNC_FAILED; /* Even TMF timed out, return direct. */ - if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) { - if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) { - pm8001_dbg(pm8001_ha, FAIL, - "TMF task[%x]timeout.\n", - tmf->tmf); - goto ex_err; - } + if (task->task_state_flags & SAS_TASK_STATE_ABORTED) { + pm8001_dbg(pm8001_ha, FAIL, "TMF task[%x]timeout.\n", + tmf->tmf); + goto ex_err; }
if (task->task_status.resp == SAS_TASK_COMPLETE && @@ -834,12 +835,9 @@ pm8001_exec_internal_task_abort(struct pm8001_hba_info *pm8001_ha, wait_for_completion(&task->slow_task->completion); res = TMF_RESP_FUNC_FAILED; /* Even TMF timed out, return direct. */ - if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) { - if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) { - pm8001_dbg(pm8001_ha, FAIL, - "TMF task timeout.\n"); - goto ex_err; - } + if (task->task_state_flags & SAS_TASK_STATE_ABORTED) { + pm8001_dbg(pm8001_ha, FAIL, "TMF task timeout.\n"); + goto ex_err; }
if (task->task_status.resp == SAS_TASK_COMPLETE &&