diff mbox series

[4.9,14/42] net: appletalk: cops: Fix data race in cops_probe1

Message ID 20210614102643.160528390@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

gregkh@linuxfoundation.org June 14, 2021, 10:27 a.m. UTC 
From: Saubhik Mukherjee <saubhik.mukherjee@gmail.com>

[ Upstream commit a4dd4fc6105e54393d637450a11d4cddb5fabc4f ]

In cops_probe1(), there is a write to dev->base_addr after requesting an
interrupt line and registering the interrupt handler cops_interrupt().
The handler might be called in parallel to handle an interrupt.
cops_interrupt() tries to read dev->base_addr leading to a potential
data race. So write to dev->base_addr before calling request_irq().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Saubhik Mukherjee <saubhik.mukherjee@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/appletalk/cops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/appletalk/cops.c b/drivers/net/appletalk/cops.c
index 1b2e9217ec78..d520ce32ddbf 100644
--- a/drivers/net/appletalk/cops.c
+++ b/drivers/net/appletalk/cops.c
@@ -324,6 +324,8 @@  static int __init cops_probe1(struct net_device *dev, int ioaddr)
 			break;
 	}
 
+	dev->base_addr = ioaddr;
+
 	/* Reserve any actual interrupt. */
 	if (dev->irq) {
 		retval = request_irq(dev->irq, cops_interrupt, 0, dev->name, dev);
@@ -331,8 +333,6 @@  static int __init cops_probe1(struct net_device *dev, int ioaddr)
 			goto err_out;
 	}
 
-	dev->base_addr = ioaddr;
-
         lp = netdev_priv(dev);
         spin_lock_init(&lp->lock);