@@ -543,6 +543,11 @@ static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
hsdev->sactive_issued |= qcmd_tag_to_mask(tag);
qc = ata_qc_from_tag(ap, tag);
+ if (unlikely(!qc)) {
+ dev_err(ap->dev, "failed to get qc");
+ handled = 1;
+ goto DONE;
+ }
/*
* Start FP DMA for NCQ command. At this point the tag is the
* active tag. It is the tag that matches the command about to
@@ -658,6 +663,11 @@ static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
tag_mask &= (~0x00000001);
qc = ata_qc_from_tag(ap, tag);
+ if (unlikely(!qc)) {
+ dev_err(ap->dev, "failed to get qc");
+ handled = 1;
+ goto DONE;
+ }
/* To be picked up by completion functions */
qc->ap->link.active_tag = tag;
The return value of ata_qc_from_tag() is checked in the whole kernel except for two calls in sata_dwc_isr(), which may lead to null-pointer-dereference. Add return value checks to avoid such case. Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn> --- Changelog: v2: - Refine commit message. Add return value check for another ata_qc_from_tag() call. --- drivers/ata/sata_dwc_460ex.c | 10 ++++++++++ 1 file changed, 10 insertions(+)