[PATCH AUTOSEL 5.1 055/219] net: hns3: add a check to pointer in error_detected and slot_reset

From: Sasha Levin
Date: Mon Jul 15 2019 - 10:07:13 EST


From: Weihang Li <liweihang@xxxxxxxxxxxxx>

[ Upstream commit 661262bc3e0ecc9a1aed39c6b2a99766da2c22e2 ]

If we add a VF without loading hclgevf.ko and then there is a RAS error
occurs, PCIe AER will call error_detected and slot_reset of all functions,
and will get a NULL pointer when we check ad_dev->ops->handle_hw_ras_error.
This will cause a call trace and failures on handling of follow-up RAS
errors.

This patch check ae_dev and ad_dev->ops at first to solve above issues.

Signed-off-by: Weihang Li <liweihang@xxxxxxxxxxxxx>
Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
Signed-off-by: Huazhong Tan <tanhuazhong@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 5e41ed4954f9..cac17152157d 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -1847,9 +1847,9 @@ static pci_ers_result_t hns3_error_detected(struct pci_dev *pdev,
if (state == pci_channel_io_perm_failure)
return PCI_ERS_RESULT_DISCONNECT;

- if (!ae_dev) {
+ if (!ae_dev || !ae_dev->ops) {
dev_err(&pdev->dev,
- "Can't recover - error happened during device init\n");
+ "Can't recover - error happened before device initialized\n");
return PCI_ERS_RESULT_NONE;
}

@@ -1868,6 +1868,9 @@ static pci_ers_result_t hns3_slot_reset(struct pci_dev *pdev)

dev_info(dev, "requesting reset due to PCI error\n");

+ if (!ae_dev || !ae_dev->ops)
+ return PCI_ERS_RESULT_NONE;
+
/* request the reset */
if (ae_dev->ops->reset_event) {
if (!ae_dev->override_pci_need_reset)
--
2.20.1