Subject: [PATCH AUTOSEL 5.10 27/54] atm: idt77252: fix null-ptr-dereference

From: Sasha Levin <[email-masked]>
Date: Tue, 16 Mar 2021 20:56:26 -0400

From: Tong Zhang <[email-masked]>

[ Upstream commit 4416e98594dc04590ebc498fc4e530009535c511 ]

this one is similar to the phy_data allocation fix in uPD98402, the
driver allocate the idt77105_priv and store to dev_data but later
dereference using dev->dev_data, which will cause null-ptr-dereference.

fix this issue by changing dev_data to phy_data so that PRIV(dev) can
work correctly.

Signed-off-by: Tong Zhang <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/atm/idt77105.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/atm/idt77105.c b/drivers/atm/idt77105.c
index 3c081b6171a8..bfca7b8a6f31 100644
--- a/drivers/atm/idt77105.c
+++ b/drivers/atm/idt77105.c
@@ -262,7 +262,7 @@ static int idt77105_start(struct atm_dev *dev)
 {
 	unsigned long flags;
 
-	if (!(dev->dev_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
+	if (!(dev->phy_data = kmalloc(sizeof(struct idt77105_priv),GFP_KERNEL)))
 		return -ENOMEM;
 	PRIV(dev)->dev = dev;
 	spin_lock_irqsave(&idt77105_priv_lock, flags);
@@ -337,7 +337,7 @@ static int idt77105_stop(struct atm_dev *dev)
                 else
                     idt77105_all = walk->next;
 	        dev->phy = NULL;
-                dev->dev_data = NULL;
+                dev->phy_data = NULL;
                 kfree(walk);
                 break;
             }
-- 
2.30.1