[PATCH 4.4 07/57] net: prevent sign extension in dev_get_stats()
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2017-07-19 11:36:55
Also in:
lkml
4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@google.com>
commit 6f64ec74515925cced6df4571638b5a099a49aae upstream.
Similar to the fix provided by Dominik Heidler in commit
9b3dc0a17d73 ("l2tp: cast l2tp traffic counter to unsigned")
we need to take care of 32bit kernels in dev_get_stats().
When using atomic_long_read(), we add a 'long' to u64 and
might misinterpret high order bit, unless we cast to unsigned.
Fixes: caf586e5f23ce ("net: add a core netdev->rx_dropped counter")
Fixes: 015f0688f57ca ("net: net: add a core netdev->tx_dropped counter")
Fixes: 6e7333d315a76 ("net: add rx_nohandler stat counter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jarod Wilson <redacted>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/core/dev.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/core/dev.c
+++ b/net/core/dev.c@@ -7052,8 +7052,8 @@ struct rtnl_link_stats64 *dev_get_stats( } else { netdev_stats_to_stats64(storage, &dev->stats); } - storage->rx_dropped += atomic_long_read(&dev->rx_dropped); - storage->tx_dropped += atomic_long_read(&dev->tx_dropped); + storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped); + storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped); return storage; } EXPORT_SYMBOL(dev_get_stats);