From: Ido Schimmel Date: Wed, 29 Jul 2020 09:26:45 +0000 (+0300) Subject: mlxsw: core: Increase scope of RCU read-side critical section X-Git-Tag: v4.4.233~128 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f052717e1713ddded90d18e99951104cfa5aae63;p=thirdparty%2Fkernel%2Fstable.git mlxsw: core: Increase scope of RCU read-side critical section [ Upstream commit 7d8e8f3433dc8d1dc87c1aabe73a154978fb4c4d ] The lifetime of the Rx listener item ('rxl_item') is managed using RCU, but is dereferenced outside of RCU read-side critical section, which can lead to a use-after-free. Fix this by increasing the scope of the RCU read-side critical section. Fixes: 93c1edb27f9e ("mlxsw: Introduce Mellanox switch driver core") Signed-off-by: Ido Schimmel Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- diff --git a/drivers/net/ethernet/mellanox/mlxsw/core.c b/drivers/net/ethernet/mellanox/mlxsw/core.c index 97f0d93caf994..085aaad902937 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/core.c +++ b/drivers/net/ethernet/mellanox/mlxsw/core.c @@ -1208,9 +1208,10 @@ void mlxsw_core_skb_receive(struct mlxsw_core *mlxsw_core, struct sk_buff *skb, break; } } - rcu_read_unlock(); - if (!found) + if (!found) { + rcu_read_unlock(); goto drop; + } pcpu_stats = this_cpu_ptr(mlxsw_core->pcpu_stats); u64_stats_update_begin(&pcpu_stats->syncp); @@ -1221,6 +1222,7 @@ void mlxsw_core_skb_receive(struct mlxsw_core *mlxsw_core, struct sk_buff *skb, u64_stats_update_end(&pcpu_stats->syncp); rxl->func(skb, local_port, rxl_item->priv); + rcu_read_unlock(); return; drop: