[PATCH AUTOSEL 4.19 013/237] powerpc/eeh: Fix null deref for devices removed during EEH

Sasha Levin
2019-11-16T15:41:33Z

From: Sam Bobroff <sbobroff@linux.ibm.com>

[ Upstream commit bcbe3730531239abd45ab6c6af4a18078b37dd47 ]

If a device is removed during EEH processing (either by a driver's
handler or as part of recovery), it can lead to a null dereference
in eeh_pe_report_edev().

To handle this, skip devices that have been removed.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/kernel/eeh_driver.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c
index 110eba400de7c..af1f3d5f9a0f7 100644
--- a/arch/powerpc/kernel/eeh_driver.c
+++ b/arch/powerpc/kernel/eeh_driver.c
@@ -281,6 +281,10 @@ static void eeh_pe_report_edev(struct eeh_dev *edev, eeh_report_fn fn,
struct pci_driver *driver;
enum pci_ers_result new_result;

+ if (!edev->pdev) {
+ eeh_edev_info(edev, "no device");
+ return;
+ }
device_lock(&edev->pdev->dev);
if (eeh_edev_actionable(edev)) {
driver = eeh_pcid_get(edev->pdev);
--
2.20.1