From 28a04c7b7bbecaab642fcb6a2d7354eb70ea7fbe Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Mon, 2 Oct 2017 12:14:56 +0200 Subject: [PATCH 1/2] mlxsw: spectrum_router: Move VRF refcounting When creating a new RIF, bumping RIF count of the containing VR is the last thing to be done. Symmetrically, when destroying a RIF, RIF count is first dropped and only then the rest of the cleanup proceeds. That's a problem for loopback RIFs. Those hold two VR references: one for overlay and one for underlay. mlxsw_sp_rif_destroy() releases the overlay one, and the deconfigure() callback the underlay one. But if both overlay and underlay are the same, and if there are no other artifacts holding the VR alive, this put actually destroys the VR. Later on, when mlxsw_sp_rif_destroy() calls mlxsw_sp_vr_put() for the same VR, the VR will already have been released and the kernel crashes with NULL pointer dereference. The underlying problem is that the RIF under destruction ends up referencing the overlay VR much longer than it claims: all the way until the call to mlxsw_sp_vr_put(). So line up the reference counting properly to reflect this. Make corresponding changes in mlxsw_sp_rif_create() as well for symmetry. Fixes: 6ddb7426a7d4 ("mlxsw: spectrum_router: Introduce loopback RIFs") Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 2cfb3f5d092d..3917b4dd4202 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -5068,6 +5068,7 @@ mlxsw_sp_rif_create(struct mlxsw_sp *mlxsw_sp, vr = mlxsw_sp_vr_get(mlxsw_sp, tb_id ? : RT_TABLE_MAIN); if (IS_ERR(vr)) return ERR_CAST(vr); + vr->rif_count++; err = mlxsw_sp_rif_index_alloc(mlxsw_sp, &rif_index); if (err) @@ -5099,7 +5100,6 @@ mlxsw_sp_rif_create(struct mlxsw_sp *mlxsw_sp, mlxsw_sp_rif_counters_alloc(rif); mlxsw_sp->router->rifs[rif_index] = rif; - vr->rif_count++; return rif; @@ -5110,6 +5110,7 @@ err_fid_get: kfree(rif); err_rif_alloc: err_rif_index_alloc: + vr->rif_count--; mlxsw_sp_vr_put(vr); return ERR_PTR(err); } @@ -5124,7 +5125,6 @@ void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif) mlxsw_sp_router_rif_gone_sync(mlxsw_sp, rif); vr = &mlxsw_sp->router->vrs[rif->vr_id]; - vr->rif_count--; mlxsw_sp->router->rifs[rif->rif_index] = NULL; mlxsw_sp_rif_counters_free(rif); ops->deconfigure(rif); @@ -5132,6 +5132,7 @@ void mlxsw_sp_rif_destroy(struct mlxsw_sp_rif *rif) /* Loopback RIFs are not associated with a FID. */ mlxsw_sp_fid_put(fid); kfree(rif); + vr->rif_count--; mlxsw_sp_vr_put(vr); } From de0f43c01a4b5d408a5c087c8a92ac1739938f8b Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Mon, 2 Oct 2017 12:14:57 +0200 Subject: [PATCH 2/2] mlxsw: spectrum_router: Track RIF of IPIP next hops When considering whether to set RTNH_F_OFFLOAD flag on an IPv6 route, mlxsw_sp_fib6_entry_offload_set() looks up the mlxsw_sp_nexthop corresponding to a given route, and decides based on whether the next hop's offloaded flag was set. When looking for the matching next hop, it also takes into account the device of the route, which must match next hop's RIF. IPIP next hops however hitherto didn't set the RIF. As a result, IPv6 routes forwarding traffic to IP-in-IP netdevices are never marked as offloaded, even when they actually are. Thus track RIF of IPIP next hops the same way as that of ETHERNET next hops. Fixes: 8f28a3097645 ("mlxsw: spectrum_router: Support IPv6 overlay encap") Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- .../net/ethernet/mellanox/mlxsw/spectrum_router.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c index 3917b4dd4202..032089efc1a0 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c @@ -2723,6 +2723,7 @@ static void mlxsw_sp_nexthop_type_fini(struct mlxsw_sp *mlxsw_sp, mlxsw_sp_nexthop_rif_fini(nh); break; case MLXSW_SP_NEXTHOP_TYPE_IPIP: + mlxsw_sp_nexthop_rif_fini(nh); mlxsw_sp_nexthop_ipip_fini(mlxsw_sp, nh); break; } @@ -2742,7 +2743,11 @@ static int mlxsw_sp_nexthop4_type_init(struct mlxsw_sp *mlxsw_sp, router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, dev, MLXSW_SP_L3_PROTO_IPV4)) { nh->type = MLXSW_SP_NEXTHOP_TYPE_IPIP; - return mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev); + err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev); + if (err) + return err; + mlxsw_sp_nexthop_rif_init(nh, &nh->ipip_entry->ol_lb->common); + return 0; } nh->type = MLXSW_SP_NEXTHOP_TYPE_ETH; @@ -4009,7 +4014,11 @@ static int mlxsw_sp_nexthop6_type_init(struct mlxsw_sp *mlxsw_sp, router->ipip_ops_arr[ipipt]->can_offload(mlxsw_sp, dev, MLXSW_SP_L3_PROTO_IPV6)) { nh->type = MLXSW_SP_NEXTHOP_TYPE_IPIP; - return mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev); + err = mlxsw_sp_nexthop_ipip_init(mlxsw_sp, ipipt, nh, dev); + if (err) + return err; + mlxsw_sp_nexthop_rif_init(nh, &nh->ipip_entry->ol_lb->common); + return 0; } nh->type = MLXSW_SP_NEXTHOP_TYPE_ETH;