Commit 8895a9c2 authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by David S. Miller
Browse files

ipv4: Fix data-races around sysctl_fib_multipath_hash_fields. 



While reading sysctl_fib_multipath_hash_fields, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: ce5c9c20 ("ipv4: Add a sysctl to control multipath hash fields")
Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7998c12a

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

+1 −1
Original line number Diff line number Diff line
@@ -10342,7 +10342,7 @@ static void mlxsw_sp_mp4_hash_init(struct mlxsw_sp *mlxsw_sp, 
		mlxsw_sp_mp_hash_inner_l3(config);

		break;

	case 3:

		hash_fields = net->ipv4.sysctl_fib_multipath_hash_fields;

		hash_fields = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_fields);

		/* Outer */

		MLXSW_SP_MP_HASH_HEADER_SET(headers, IPV4_EN_NOT_TCP_NOT_UDP);

		MLXSW_SP_MP_HASH_HEADER_SET(headers, IPV4_EN_TCP_UDP);

net/ipv4/route.c

+3 −3
Original line number Diff line number Diff line
@@ -1929,7 +1929,7 @@ static u32 fib_multipath_custom_hash_outer(const struct net *net, 
					   const struct sk_buff *skb,

					   bool *p_has_inner)

{

	u32 hash_fields = net->ipv4.sysctl_fib_multipath_hash_fields;

	u32 hash_fields = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_fields);

	struct flow_keys keys, hash_keys;



	if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK))
@@ -1958,7 +1958,7 @@ static u32 fib_multipath_custom_hash_inner(const struct net *net, 
					   const struct sk_buff *skb,

					   bool has_inner)

{

	u32 hash_fields = net->ipv4.sysctl_fib_multipath_hash_fields;

	u32 hash_fields = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_fields);

	struct flow_keys keys, hash_keys;



	/* We assume the packet carries an encapsulation, but if none was
@@ -2018,7 +2018,7 @@ static u32 fib_multipath_custom_hash_skb(const struct net *net, 
static u32 fib_multipath_custom_hash_fl4(const struct net *net,

					 const struct flowi4 *fl4)

{

	u32 hash_fields = net->ipv4.sysctl_fib_multipath_hash_fields;

	u32 hash_fields = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_fields);

	struct flow_keys hash_keys;



	if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK))