[PATCH 4.19 03/32] net: Fix features skip in for_each_netdev_feature()

Greg Kroah-Hartman
2022-05-16T19:44:56Z

From: Tariq Toukan <tariqt@nvidia.com>

[ Upstream commit 85db6352fc8a158a893151baa1716463d34a20d0 ]

The find_next_netdev_feature() macro gets the "remaining length",
not bit index.
Passing "bit - 1" for the following iteration is wrong as it skips
the adjacent bit. Pass "bit" instead.

Fixes: 3b89ea9c5902 ("net: Fix for_each_netdev_feature on Big endian")
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Link: https://lore.kernel.org/r/20220504080914.1918-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/linux/netdev_features.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 2a8105d204a9..78411dc4a040 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -156,7 +156,7 @@ enum {
#define NETIF_F_HW_TLS_TX __NETIF_F(HW_TLS_TX)
#define NETIF_F_HW_TLS_RX __NETIF_F(HW_TLS_RX)

-/* Finds the next feature with the highest number of the range of start till 0.
+/* Finds the next feature with the highest number of the range of start-1 till 0.
*/
static inline int find_next_netdev_feature(u64 feature, unsigned long start)
{
@@ -175,7 +175,7 @@ static inline int find_next_netdev_feature(u64 feature, unsigned long start)
for ((bit) = find_next_netdev_feature((mask_addr), \
NETDEV_FEATURE_COUNT); \
(bit) >= 0; \
- (bit) = find_next_netdev_feature((mask_addr), (bit) - 1))
+ (bit) = find_next_netdev_feature((mask_addr), (bit)))

/* Features valid for ethtool to change */
/* = all defined minus driver/device-class-related */
--
2.35.1