diff options
| author | Ido Schimmel | 2015-08-06 16:41:58 +0200 |
|---|---|---|
| committer | David S. Miller | 2015-08-09 22:54:10 -0700 |
| commit | e577516b9db3e0f19df82b6430fe3b06e05d6304 (patch) | |
| tree | 4c9eac68dca177a0335932c9b8191ffde55b7941 | |
| parent | 3bfcd34764cbd3bcb48f6e9009eacf1d19856213 (diff) | |
mlxsw: Fix use-after-free bug in mlxsw_sx_port_xmit
Store the length of the skb before transmitting it and use it for stats
instead of skb->len, since skb might have been freed already.
This issue was discovered using the Kernel Address sanitizer (KASan).
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlxsw/switchx2.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/net/ethernet/mellanox/mlxsw/switchx2.c b/drivers/net/ethernet/mellanox/mlxsw/switchx2.c index fce9b453433b..3e52ee93438c 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/switchx2.c +++ b/drivers/net/ethernet/mellanox/mlxsw/switchx2.c @@ -300,6 +300,7 @@ static netdev_tx_t mlxsw_sx_port_xmit(struct sk_buff *skb, .local_port = mlxsw_sx_port->local_port, .is_emad = false, }; + u64 len; int err; if (mlxsw_core_skb_transmit_busy(mlxsw_sx, &tx_info)) @@ -316,6 +317,7 @@ static netdev_tx_t mlxsw_sx_port_xmit(struct sk_buff *skb, } } mlxsw_sx_txhdr_construct(skb, &tx_info); + len = skb->len; /* Due to a race we might fail here because of a full queue. In that * unlikely case we simply drop the packet. */ @@ -325,7 +327,7 @@ static netdev_tx_t mlxsw_sx_port_xmit(struct sk_buff *skb, pcpu_stats = this_cpu_ptr(mlxsw_sx_port->pcpu_stats); u64_stats_update_begin(&pcpu_stats->syncp); pcpu_stats->tx_packets++; - pcpu_stats->tx_bytes += skb->len; + pcpu_stats->tx_bytes += len; u64_stats_update_end(&pcpu_stats->syncp); } else { this_cpu_inc(mlxsw_sx_port->pcpu_stats->tx_dropped); |