ata_qc_from_tag() may return a null pointer and further lead to
null-pointer-dereference. Add a return value check to avoid such case.
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
---
drivers/ata/sata_dwc_460ex.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c
index 9dcef6ac643b..0068247ffc06 100644
--- a/drivers/ata/sata_dwc_460ex.c
+++ b/drivers/ata/sata_dwc_460ex.c
@@ -548,8 +548,10 @@ static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
* active tag. It is the tag that matches the command about to
* be completed.
*/
- qc->ap->link.active_tag = tag;
- sata_dwc_bmdma_start_by_tag(qc, tag);
+ if (qc) {
+ qc->ap->link.active_tag = tag;
+ sata_dwc_bmdma_start_by_tag(qc, tag);
+ }
handled = 1;
goto DONE;
--
2.17.1
