[PATCH 4.14 143/209] net: dev: Use unsigned integer as an argument to left-shift

Greg Kroah-Hartman
2019-12-04T18:08:31Z

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

[ Upstream commit f4d7b3e23d259c44f1f1c39645450680fcd935d6 ]

1 << 31 is Undefined Behaviour according to the C standard.
Use U type modifier to avoid theoretical overflow.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/linux/netdevice.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 40b830d55fe50..4725a9d9597fc 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3522,7 +3522,7 @@ static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits)
if (debug_value == 0) /* no output */
return 0;
/* set low N bits */
- return (1 << debug_value) - 1;
+ return (1U << debug_value) - 1;
}

static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu)
--
2.20.1