The function sis_find_family drops lpc_bridge reference via pci_dev_put,
however, after that, field lpc_bridge->revision is read. This may result
in a use after free bug. The patch moves the put operation after the
condition check.

Signed-off-by: Pan Bian <bianpan2...@163.com>
---
 drivers/ide/sis5513.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/ide/sis5513.c b/drivers/ide/sis5513.c
index 024bc7b..69f9889 100644
--- a/drivers/ide/sis5513.c
+++ b/drivers/ide/sis5513.c
@@ -434,7 +434,6 @@ static int sis_find_family(struct pci_dev *dev)
 
                                lpc_bridge = pci_get_slot(dev->bus, 0x10); /* 
Bus 0, Dev 2, Fn 0 */
                                pci_read_config_byte(dev, 0x49, &prefctl);
-                               pci_dev_put(lpc_bridge);
 
                                if (lpc_bridge->revision == 0x10 && (prefctl & 
0x80)) {
                                        printk(KERN_INFO DRV_NAME " %s: SiS 
961B MuTIOL IDE UDMA133 controller\n",
@@ -445,6 +444,8 @@ static int sis_find_family(struct pci_dev *dev)
                                                pci_name(dev));
                                        chipset_family = ATA_100;
                                }
+
+                               pci_dev_put(lpc_bridge);
                        }
        }
 
-- 
2.7.4


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