[PATCH AUTOSEL for 4.14 053/135] misc: pci_endpoint_test: Avoid triggering a BUG()

[alexander . levin]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 846df244ebefbc9f7b91e9ae7a5e5a2e69fb4772 ]

If you call ida_simple_remove(&pci_endpoint_test_ida, id) with a
negative "id" then it triggers an immediate BUG_ON().  Let's not allow
that.

Fixes: 2c156ac71c6b ("misc: Add host side PCI driver for PCI test function device")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 drivers/misc/pci_endpoint_test.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
index e787a63a321a..e089bb6dde3a 100644
--- a/drivers/misc/pci_endpoint_test.c
+++ b/drivers/misc/pci_endpoint_test.c
@@ -590,6 +590,8 @@ static void pci_endpoint_test_remove(struct pci_dev *pdev)
 
 	if (sscanf(misc_device->name, DRV_MODULE_NAME ".%d", &id) != 1)
 		return;
+	if (id < 0)
+		return;
 
 	misc_deregister(&test->miscdev);
 	ida_simple_remove(&pci_endpoint_test_ida, id);
-- 
2.11.0