netdev - [PATCH net 1/2] mlxsw: spectrum: Fix use-after-free of split/unsplit/type

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200521121145.1076075-2-idosch@idosch.org>
Date:   Thu, 21 May 2020 15:11:44 +0300
From:   Ido Schimmel <idosch@...sch.org>
To:     netdev@...r.kernel.org
Cc:     davem@...emloft.net, kuba@...nel.org, jiri@...lanox.com,
        mlxsw@...lanox.com, Ido Schimmel <idosch@...lanox.com>
Subject: [PATCH net 1/2] mlxsw: spectrum: Fix use-after-free of split/unsplit/type_set in case reload fails

From: Jiri Pirko <jiri@...lanox.com>

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 <danieller@...lanox.com>
Signed-off-by: Jiri Pirko <jiri@...lanox.com>
Signed-off-by: Ido Schimmel <idosch@...lanox.com>
---
 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