[PATCH AUTOSEL 5.10 18/27] scsi: pm8001: Fix use-after-free for aborted TMF sas_task

[PATCH AUTOSEL 5.10 18/27] scsi: pm8001: Fix use-after-free for aborted TMF sas_task

[Sasha Levin]

From: John Garry <john.garry@huawei.com>

[ Upstream commit 61f162aa4381845acbdc7f2be4dfb694d027c018 ]

Currently a use-after-free may occur if a TMF sas_task is aborted before we
handle the IO completion in mpi_ssp_completion(). The abort occurs due to
timeout.

When the timeout occurs, the SAS_TASK_STATE_ABORTED flag is set and the
sas_task is freed in pm8001_exec_internal_tmf_task().

However, if the I/O completion occurs later, the I/O completion still
thinks that the sas_task is available. Fix this by clearing the ccb->task
if the TMF times out - the I/O completion handler does nothing if this
pointer is cleared.

Link: https://lore.kernel.org/r/1643289172-165636-3-git-send-email-john.garry@huawei.com
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: John Garry <john.garry@huawei.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 | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index c3bb58885033b..75ac4d86d9c4b 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -753,8 +753,13 @@ 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) {
+			struct pm8001_ccb_info *ccb = task->lldd_task;
+
 			pm8001_dbg(pm8001_ha, FAIL, "TMF task[%x]timeout.\n",
 				   tmf->tmf);
+
+			if (ccb)
+				ccb->task = NULL;
 			goto ex_err;
 		}
 
-- 
2.34.1

[PATCH AUTOSEL 5.10 19/27] scsi: pm8001: Fix use-after-free for aborted SSP/STP sas_task

[Sasha Levin]

From: John Garry <john.garry@huawei.com>

[ Upstream commit df7abcaa1246e2537ab4016077b5443bb3c09378 ]

Currently a use-after-free may occur if a sas_task is aborted by the upper
layer before we handle the I/O completion in mpi_ssp_completion() or
mpi_sata_completion().

In this case, the following are the two steps in handling those I/O
completions:

 - Call complete() to inform the upper layer handler of completion of
   the I/O.

 - Release driver resources associated with the sas_task in
   pm8001_ccb_task_free() call.

When complete() is called, the upper layer may free the sas_task. As such,
we should not touch the associated sas_task afterwards, but we do so in the
pm8001_ccb_task_free() call.

Fix by swapping the complete() and pm8001_ccb_task_free() calls ordering.

Link: https://lore.kernel.org/r/1643289172-165636-4-git-send-email-john.garry@huawei.com
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/pm8001/pm80xx_hwi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index a203a4fc2674a..b08e285e7fff6 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -2133,9 +2133,9 @@ mpi_ssp_completion(struct pm8001_hba_info *pm8001_ha , void *piomb)
 		pm8001_dbg(pm8001_ha, FAIL,
 			   "task 0x%p done with io_status 0x%x resp 0x%x stat 0x%x but aborted by upper layer!\n",
 			   t, status, ts->resp, ts->stat);
+		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);
 		if (t->slow_task)
 			complete(&t->slow_task->completion);
-		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);
 	} else {
 		spin_unlock_irqrestore(&t->task_state_lock, flags);
 		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);
@@ -2726,9 +2726,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb)
 		pm8001_dbg(pm8001_ha, FAIL,
 			   "task 0x%p done with io_status 0x%x resp 0x%x stat 0x%x but aborted by upper layer!\n",
 			   t, status, ts->resp, ts->stat);
+		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);
 		if (t->slow_task)
 			complete(&t->slow_task->completion);
-		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);
 	} else {
 		spin_unlock_irqrestore(&t->task_state_lock, flags);
 		pm8001_ccb_task_free_done(pm8001_ha, t, ccb, tag);
-- 
2.34.1