[PATCH] pata_ali: check the pci_get_device failure

[Navid Emamdoost]

pci_get_device may fail and return NULL. This eventually will be
dereferenced in __pci_register_driver. So null check is necessary.

Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>
---
 drivers/ata/pata_ali.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/ata/pata_ali.c b/drivers/ata/pata_ali.c
index 0b122f903b8a..47d9bec1f2e2 100644
--- a/drivers/ata/pata_ali.c
+++ b/drivers/ata/pata_ali.c
@@ -627,6 +627,8 @@ static int __init ali_init(void)
 {
 	int ret;
 	ali_isa_bridge = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
+	if (!ali_isa_bridge)
+		return -EINVAL;
 
 	ret = pci_register_driver(&ali_pci_driver);
 	if (ret < 0)
-- 
2.17.1