[PATCH] net: appletalk: cops: Fix data race in cops_probe1
From: Saubhik Mukherjee
Date: Mon May 24 2021 - 09:39:00 EST
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@xxxxxxxxx>
---
drivers/net/appletalk/cops.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/appletalk/cops.c b/drivers/net/appletalk/cops.c
index ba8e70a8e312..6b12ce822e51 100644
--- a/drivers/net/appletalk/cops.c
+++ b/drivers/net/appletalk/cops.c
@@ -327,6 +327,8 @@ 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);
@@ -334,8 +336,6 @@ 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);
--
2.30.2