The write operations to "dev->stats" are protected by 
the spinlock on line 862-864, but the read operations to
this data on line 858 and 867 are not protected by the spinlock.
Thus, there may exist data races for "dev->stats".

To fix the data races, the read operations to "dev->stats" are 
protected by the spinlock, and a local variable is used for return.

Signed-off-by: Jia-Ju Bai <baijiaju1...@gmail.com>
---
 drivers/net/ethernet/8390/lib8390.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/8390/lib8390.c 
b/drivers/net/ethernet/8390/lib8390.c
index c9c55c9eab9f..198952247d30 100644
--- a/drivers/net/ethernet/8390/lib8390.c
+++ b/drivers/net/ethernet/8390/lib8390.c
@@ -852,19 +852,25 @@ static struct net_device_stats *__ei_get_stats(struct 
net_device *dev)
        unsigned long ioaddr = dev->base_addr;
        struct ei_device *ei_local = netdev_priv(dev);
        unsigned long flags;
+       struct net_device_stats *stats;
+
+       spin_lock_irqsave(&ei_local->page_lock, flags);
 
        /* If the card is stopped, just return the present stats. */
-       if (!netif_running(dev))
-               return &dev->stats;
+       if (!netif_running(dev)) {
+               stats = &dev->stats;
+               spin_unlock_irqrestore(&ei_local->page_lock, flags);
+               return stats;
+       }
 
-       spin_lock_irqsave(&ei_local->page_lock, flags);
        /* Read the counter registers, assuming we are in page 0. */
        dev->stats.rx_frame_errors  += ei_inb_p(ioaddr + EN0_COUNTER0);
        dev->stats.rx_crc_errors    += ei_inb_p(ioaddr + EN0_COUNTER1);
        dev->stats.rx_missed_errors += ei_inb_p(ioaddr + EN0_COUNTER2);
+       stats = &dev->stats;
        spin_unlock_irqrestore(&ei_local->page_lock, flags);
 
-       return &dev->stats;
+       return stats;
 }
 
 /*
-- 
2.17.0

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