[PATCH v6 bpf-next 2/6] netdevice: check for net_device::priv_flags bitfield overflow
From: Alexander Lobakin
Date: Tue Feb 16 2021 - 12:28:37 EST
We almost ran out of unsigned int bitwidth. Define priv flags and
check for potential overflow in the fashion of netdev_features_t.
Defined this way, priv_flags can be easily expanded later with
just changing its typedef.
Signed-off-by: Alexander Lobakin <alobakin@xxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx> # Inverted assert condition
---
include/linux/netdevice.h | 135 ++++++++++++++++++++------------------
1 file changed, 72 insertions(+), 63 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index b895973390ee..0a9b2b31f411 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1527,70 +1527,79 @@ struct net_device_ops {
* @IFF_LIVE_RENAME_OK: rename is allowed while device is up and running
*/
enum netdev_priv_flags {
- IFF_802_1Q_VLAN = 1<<0,
- IFF_EBRIDGE = 1<<1,
- IFF_BONDING = 1<<2,
- IFF_ISATAP = 1<<3,
- IFF_WAN_HDLC = 1<<4,
- IFF_XMIT_DST_RELEASE = 1<<5,
- IFF_DONT_BRIDGE = 1<<6,
- IFF_DISABLE_NETPOLL = 1<<7,
- IFF_MACVLAN_PORT = 1<<8,
- IFF_BRIDGE_PORT = 1<<9,
- IFF_OVS_DATAPATH = 1<<10,
- IFF_TX_SKB_SHARING = 1<<11,
- IFF_UNICAST_FLT = 1<<12,
- IFF_TEAM_PORT = 1<<13,
- IFF_SUPP_NOFCS = 1<<14,
- IFF_LIVE_ADDR_CHANGE = 1<<15,
- IFF_MACVLAN = 1<<16,
- IFF_XMIT_DST_RELEASE_PERM = 1<<17,
- IFF_L3MDEV_MASTER = 1<<18,
- IFF_NO_QUEUE = 1<<19,
- IFF_OPENVSWITCH = 1<<20,
- IFF_L3MDEV_SLAVE = 1<<21,
- IFF_TEAM = 1<<22,
- IFF_RXFH_CONFIGURED = 1<<23,
- IFF_PHONY_HEADROOM = 1<<24,
- IFF_MACSEC = 1<<25,
- IFF_NO_RX_HANDLER = 1<<26,
- IFF_FAILOVER = 1<<27,
- IFF_FAILOVER_SLAVE = 1<<28,
- IFF_L3MDEV_RX_HANDLER = 1<<29,
- IFF_LIVE_RENAME_OK = 1<<30,
+ IFF_802_1Q_VLAN_BIT,
+ IFF_EBRIDGE_BIT,
+ IFF_BONDING_BIT,
+ IFF_ISATAP_BIT,
+ IFF_WAN_HDLC_BIT,
+ IFF_XMIT_DST_RELEASE_BIT,
+ IFF_DONT_BRIDGE_BIT,
+ IFF_DISABLE_NETPOLL_BIT,
+ IFF_MACVLAN_PORT_BIT,
+ IFF_BRIDGE_PORT_BIT,
+ IFF_OVS_DATAPATH_BIT,
+ IFF_TX_SKB_SHARING_BIT,
+ IFF_UNICAST_FLT_BIT,
+ IFF_TEAM_PORT_BIT,
+ IFF_SUPP_NOFCS_BIT,
+ IFF_LIVE_ADDR_CHANGE_BIT,
+ IFF_MACVLAN_BIT,
+ IFF_XMIT_DST_RELEASE_PERM_BIT,
+ IFF_L3MDEV_MASTER_BIT,
+ IFF_NO_QUEUE_BIT,
+ IFF_OPENVSWITCH_BIT,
+ IFF_L3MDEV_SLAVE_BIT,
+ IFF_TEAM_BIT,
+ IFF_RXFH_CONFIGURED_BIT,
+ IFF_PHONY_HEADROOM_BIT,
+ IFF_MACSEC_BIT,
+ IFF_NO_RX_HANDLER_BIT,
+ IFF_FAILOVER_BIT,
+ IFF_FAILOVER_SLAVE_BIT,
+ IFF_L3MDEV_RX_HANDLER_BIT,
+ IFF_LIVE_RENAME_OK_BIT,
+
+ NETDEV_PRIV_FLAG_COUNT,
};
-#define IFF_802_1Q_VLAN IFF_802_1Q_VLAN
-#define IFF_EBRIDGE IFF_EBRIDGE
-#define IFF_BONDING IFF_BONDING
-#define IFF_ISATAP IFF_ISATAP
-#define IFF_WAN_HDLC IFF_WAN_HDLC
-#define IFF_XMIT_DST_RELEASE IFF_XMIT_DST_RELEASE
-#define IFF_DONT_BRIDGE IFF_DONT_BRIDGE
-#define IFF_DISABLE_NETPOLL IFF_DISABLE_NETPOLL
-#define IFF_MACVLAN_PORT IFF_MACVLAN_PORT
-#define IFF_BRIDGE_PORT IFF_BRIDGE_PORT
-#define IFF_OVS_DATAPATH IFF_OVS_DATAPATH
-#define IFF_TX_SKB_SHARING IFF_TX_SKB_SHARING
-#define IFF_UNICAST_FLT IFF_UNICAST_FLT
-#define IFF_TEAM_PORT IFF_TEAM_PORT
-#define IFF_SUPP_NOFCS IFF_SUPP_NOFCS
-#define IFF_LIVE_ADDR_CHANGE IFF_LIVE_ADDR_CHANGE
-#define IFF_MACVLAN IFF_MACVLAN
-#define IFF_XMIT_DST_RELEASE_PERM IFF_XMIT_DST_RELEASE_PERM
-#define IFF_L3MDEV_MASTER IFF_L3MDEV_MASTER
-#define IFF_NO_QUEUE IFF_NO_QUEUE
-#define IFF_OPENVSWITCH IFF_OPENVSWITCH
-#define IFF_L3MDEV_SLAVE IFF_L3MDEV_SLAVE
-#define IFF_TEAM IFF_TEAM
-#define IFF_RXFH_CONFIGURED IFF_RXFH_CONFIGURED
-#define IFF_PHONY_HEADROOM IFF_PHONY_HEADROOM
-#define IFF_MACSEC IFF_MACSEC
-#define IFF_NO_RX_HANDLER IFF_NO_RX_HANDLER
-#define IFF_FAILOVER IFF_FAILOVER
-#define IFF_FAILOVER_SLAVE IFF_FAILOVER_SLAVE
-#define IFF_L3MDEV_RX_HANDLER IFF_L3MDEV_RX_HANDLER
-#define IFF_LIVE_RENAME_OK IFF_LIVE_RENAME_OK
+typedef u32 netdev_priv_flags_t;
+static_assert(sizeof(netdev_priv_flags_t) * BITS_PER_BYTE >=
+ NETDEV_PRIV_FLAG_COUNT);
+
+#define __IFF_BIT(bit) ((netdev_priv_flags_t)1 << (bit))
+#define __IFF(name) __IFF_BIT(IFF_##name##_BIT)
+
+#define IFF_802_1Q_VLAN __IFF(802_1Q_VLAN)
+#define IFF_EBRIDGE __IFF(EBRIDGE)
+#define IFF_BONDING __IFF(BONDING)
+#define IFF_ISATAP __IFF(ISATAP)
+#define IFF_WAN_HDLC __IFF(WAN_HDLC)
+#define IFF_XMIT_DST_RELEASE __IFF(XMIT_DST_RELEASE)
+#define IFF_DONT_BRIDGE __IFF(DONT_BRIDGE)
+#define IFF_DISABLE_NETPOLL __IFF(DISABLE_NETPOLL)
+#define IFF_MACVLAN_PORT __IFF(MACVLAN_PORT)
+#define IFF_BRIDGE_PORT __IFF(BRIDGE_PORT)
+#define IFF_OVS_DATAPATH __IFF(OVS_DATAPATH)
+#define IFF_TX_SKB_SHARING __IFF(TX_SKB_SHARING)
+#define IFF_UNICAST_FLT __IFF(UNICAST_FLT)
+#define IFF_TEAM_PORT __IFF(TEAM_PORT)
+#define IFF_SUPP_NOFCS __IFF(SUPP_NOFCS)
+#define IFF_LIVE_ADDR_CHANGE __IFF(LIVE_ADDR_CHANGE)
+#define IFF_MACVLAN __IFF(MACVLAN)
+#define IFF_XMIT_DST_RELEASE_PERM __IFF(XMIT_DST_RELEASE_PERM)
+#define IFF_L3MDEV_MASTER __IFF(L3MDEV_MASTER)
+#define IFF_NO_QUEUE __IFF(NO_QUEUE)
+#define IFF_OPENVSWITCH __IFF(OPENVSWITCH)
+#define IFF_L3MDEV_SLAVE __IFF(L3MDEV_SLAVE)
+#define IFF_TEAM __IFF(TEAM)
+#define IFF_RXFH_CONFIGURED __IFF(RXFH_CONFIGURED)
+#define IFF_PHONY_HEADROOM __IFF(PHONY_HEADROOM)
+#define IFF_MACSEC __IFF(MACSEC)
+#define IFF_NO_RX_HANDLER __IFF(NO_RX_HANDLER)
+#define IFF_FAILOVER __IFF(FAILOVER)
+#define IFF_FAILOVER_SLAVE __IFF(FAILOVER_SLAVE)
+#define IFF_L3MDEV_RX_HANDLER __IFF(L3MDEV_RX_HANDLER)
+#define IFF_LIVE_RENAME_OK __IFF(LIVE_RENAME_OK)
/**
* struct net_device - The DEVICE structure.
@@ -1925,7 +1934,7 @@ struct net_device {
const struct header_ops *header_ops;
unsigned int flags;
- unsigned int priv_flags;
+ netdev_priv_flags_t priv_flags;
unsigned short gflags;
unsigned short padded;
--
2.30.1