From: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> [ Upstream commit 7998c12a08c97cc26660532c9f90a34bd7d8da5a ] While reading sysctl_fib_multipath_hash_policy, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: bf4e0a3db97e ("net: ipv4: add support for ECMP hash policy choice") Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 2 +- net/ipv4/route.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 994bd2e14e55..6bcb0f1b0816 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -10263,7 +10263,7 @@ static void mlxsw_sp_mp4_hash_init(struct mlxsw_sp *mlxsw_sp, unsigned long *fields = config->fields; u32 hash_fields; - switch (net->ipv4.sysctl_fib_multipath_hash_policy) { + switch (READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_policy)) { case 0: mlxsw_sp_mp4_hash_outer_addr(config); break; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 8363e575c455..907cb11cbea5 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2047,7 +2047,7 @@ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, struct flow_keys hash_keys; u32 mhash = 0; - switch (net->ipv4.sysctl_fib_multipath_hash_policy) { + switch (READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_policy)) { case 0: memset(&hash_keys, 0, sizeof(hash_keys)); hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; -- 2.35.1