[PATCH net 1/2] mlxsw: spectrum: Fix use-after-free of split/unsplit/type_set in case reload fails
From: Ido Schimmel <hidden>
Date: 2020-05-21 12:12:00
Subsystem:
mellanox ethernet switch drivers, networking drivers, the rest · Maintainers:
Ido Schimmel, Petr Machata, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Jiri Pirko <redacted>
In case of reload fail, the mlxsw_sp->ports contains a pointer to a
freed memory (either by reload_down() or reload_up() error path).
Fix this by initializing the pointer to NULL and checking it before
dereferencing in split/unsplit/type_set callpaths.
Fixes: 24cc68ad6c46 ("mlxsw: core: Add support for reload")
Reported-by: Danielle Ratson <redacted>
Signed-off-by: Jiri Pirko <redacted>
Signed-off-by: Ido Schimmel <redacted>
---
drivers/net/ethernet/mellanox/mlxsw/spectrum.c | 14 ++++++++++++--
drivers/net/ethernet/mellanox/mlxsw/switchx2.c | 8 ++++++++
2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 24ca8d5bc564..6b39978acd07 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c@@ -3986,6 +3986,7 @@ static void mlxsw_sp_ports_remove(struct mlxsw_sp *mlxsw_sp) mlxsw_sp_port_remove(mlxsw_sp, i); mlxsw_sp_cpu_port_remove(mlxsw_sp); kfree(mlxsw_sp->ports); + mlxsw_sp->ports = NULL; } static int mlxsw_sp_ports_create(struct mlxsw_sp *mlxsw_sp)
@@ -4022,6 +4023,7 @@ static int mlxsw_sp_ports_create(struct mlxsw_sp *mlxsw_sp) mlxsw_sp_cpu_port_remove(mlxsw_sp); err_cpu_port_create: kfree(mlxsw_sp->ports); + mlxsw_sp->ports = NULL; return err; }
@@ -4143,6 +4145,14 @@ static int mlxsw_sp_local_ports_offset(struct mlxsw_core *mlxsw_core, return mlxsw_core_res_get(mlxsw_core, local_ports_in_x_res_id); } +static struct mlxsw_sp_port * +mlxsw_sp_port_get_by_local_port(struct mlxsw_sp *mlxsw_sp, u8 local_port) +{ + if (mlxsw_sp->ports && mlxsw_sp->ports[local_port]) + return mlxsw_sp->ports[local_port]; + return NULL; +} + static int mlxsw_sp_port_split(struct mlxsw_core *mlxsw_core, u8 local_port, unsigned int count, struct netlink_ext_ack *extack)
@@ -4156,7 +4166,7 @@ static int mlxsw_sp_port_split(struct mlxsw_core *mlxsw_core, u8 local_port, int i; int err; - mlxsw_sp_port = mlxsw_sp->ports[local_port]; + mlxsw_sp_port = mlxsw_sp_port_get_by_local_port(mlxsw_sp, local_port); if (!mlxsw_sp_port) { dev_err(mlxsw_sp->bus_info->dev, "Port number \"%d\" does not exist\n", local_port);
@@ -4251,7 +4261,7 @@ static int mlxsw_sp_port_unsplit(struct mlxsw_core *mlxsw_core, u8 local_port, int offset; int i; - mlxsw_sp_port = mlxsw_sp->ports[local_port]; + mlxsw_sp_port = mlxsw_sp_port_get_by_local_port(mlxsw_sp, local_port); if (!mlxsw_sp_port) { dev_err(mlxsw_sp->bus_info->dev, "Port number \"%d\" does not exist\n", local_port);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/switchx2.c b/drivers/net/ethernet/mellanox/mlxsw/switchx2.c
index 90535820b559..2503f61db5fb 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/switchx2.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/switchx2.c@@ -1259,6 +1259,7 @@ static void mlxsw_sx_ports_remove(struct mlxsw_sx *mlxsw_sx) if (mlxsw_sx_port_created(mlxsw_sx, i)) mlxsw_sx_port_remove(mlxsw_sx, i); kfree(mlxsw_sx->ports); + mlxsw_sx->ports = NULL; } static int mlxsw_sx_ports_create(struct mlxsw_sx *mlxsw_sx)
@@ -1293,6 +1294,7 @@ static int mlxsw_sx_ports_create(struct mlxsw_sx *mlxsw_sx) if (mlxsw_sx_port_created(mlxsw_sx, i)) mlxsw_sx_port_remove(mlxsw_sx, i); kfree(mlxsw_sx->ports); + mlxsw_sx->ports = NULL; return err; }
@@ -1376,6 +1378,12 @@ static int mlxsw_sx_port_type_set(struct mlxsw_core *mlxsw_core, u8 local_port, u8 module, width; int err; + if (!mlxsw_sx->ports || !mlxsw_sx->ports[local_port]) { + dev_err(mlxsw_sx->bus_info->dev, "Port number \"%d\" does not exist\n", + local_port); + return -EINVAL; + } + if (new_type == DEVLINK_PORT_TYPE_AUTO) return -EOPNOTSUPP;
--
2.26.2