From a0c76345e3d3dbc40c39de2e00d15a3b7eef7885 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Fri, 8 Nov 2019 21:42:43 +0100 Subject: devlink: disallow reload operation during device cleanup There is a race between driver code that does setup/cleanup of device and devlink reload operation that in some drivers works with the same code. Use after free could we easily obtained by running: while true; do echo 10 > /sys/bus/netdevsim/new_device devlink dev reload netdevsim/netdevsim10 & echo 10 > /sys/bus/netdevsim/del_device done Fix this by enabling reload only after setup of device is complete and disabling it at the beginning of the cleanup process. Reported-by: Ido Schimmel Fixes: 2d8dc5bbf4e7 ("devlink: Add support for reload") Signed-off-by: Jiri Pirko Acked-by: Jakub Kicinski Signed-off-by: David S. Miller --- include/net/devlink.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/net/devlink.h b/include/net/devlink.h index 8d6b5846822c..7891611868e4 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -38,8 +38,9 @@ struct devlink { struct device *dev; possible_net_t _net; struct mutex lock; - bool reload_failed; - bool registered; + u8 reload_failed:1, + reload_enabled:1, + registered:1; char priv[0] __aligned(NETDEV_ALIGN); }; @@ -824,6 +825,8 @@ void devlink_net_set(struct devlink *devlink, struct net *net); struct devlink *devlink_alloc(const struct devlink_ops *ops, size_t priv_size); int devlink_register(struct devlink *devlink, struct device *dev); void devlink_unregister(struct devlink *devlink); +void devlink_reload_enable(struct devlink *devlink); +void devlink_reload_disable(struct devlink *devlink); void devlink_free(struct devlink *devlink); int devlink_port_register(struct devlink *devlink, struct devlink_port *devlink_port, -- cgit v1.2.3