From: Yevhen Orlov yevhen.orlov@plvision.eu
[ Upstream commit 2efc2256febf214e7b2bdaa21fe6c3c3146acdcb ]
In line: upper = info->upper_dev; We access upper_dev field, which is related only for particular events (e.g. event == NETDEV_CHANGEUPPER). So, this line cause invalid memory access for another events, when ptr is not netdev_notifier_changeupper_info.
The KASAN logs are as follows:
[ 30.123165] BUG: KASAN: stack-out-of-bounds in prestera_netdev_port_event.constprop.0+0x68/0x538 [prestera] [ 30.133336] Read of size 8 at addr ffff80000cf772b0 by task udevd/778 [ 30.139866] [ 30.141398] CPU: 0 PID: 778 Comm: udevd Not tainted 5.16.0-rc3 #6 [ 30.147588] Hardware name: DNI AmazonGo1 A7040 board (DT) [ 30.153056] Call trace: [ 30.155547] dump_backtrace+0x0/0x2c0 [ 30.159320] show_stack+0x18/0x30 [ 30.162729] dump_stack_lvl+0x68/0x84 [ 30.166491] print_address_description.constprop.0+0x74/0x2b8 [ 30.172346] kasan_report+0x1e8/0x250 [ 30.176102] __asan_load8+0x98/0xe0 [ 30.179682] prestera_netdev_port_event.constprop.0+0x68/0x538 [prestera] [ 30.186847] prestera_netdev_event_handler+0x1b4/0x1c0 [prestera] [ 30.193313] raw_notifier_call_chain+0x74/0xa0 [ 30.197860] call_netdevice_notifiers_info+0x68/0xc0 [ 30.202924] register_netdevice+0x3cc/0x760 [ 30.207190] register_netdev+0x24/0x50 [ 30.211015] prestera_device_register+0x8a0/0xba0 [prestera]
Fixes: 3d5048cc54bd ("net: marvell: prestera: move netdev topology validation to prestera_main") Signed-off-by: Yevhen Orlov yevhen.orlov@plvision.eu Link: https://lore.kernel.org/r/20211216171714.11341-1-yevhen.orlov@plvision.eu Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../ethernet/marvell/prestera/prestera_main.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c index f6d2f928c5b83..aa543b29799ed 100644 --- a/drivers/net/ethernet/marvell/prestera/prestera_main.c +++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c @@ -707,23 +707,27 @@ static int prestera_netdev_port_event(struct net_device *lower, struct net_device *dev, unsigned long event, void *ptr) { - struct netdev_notifier_changeupper_info *info = ptr; + struct netdev_notifier_info *info = ptr; + struct netdev_notifier_changeupper_info *cu_info; struct prestera_port *port = netdev_priv(dev); struct netlink_ext_ack *extack; struct net_device *upper;
- extack = netdev_notifier_info_to_extack(&info->info); - upper = info->upper_dev; + extack = netdev_notifier_info_to_extack(info); + cu_info = container_of(info, + struct netdev_notifier_changeupper_info, + info);
switch (event) { case NETDEV_PRECHANGEUPPER: + upper = cu_info->upper_dev; if (!netif_is_bridge_master(upper) && !netif_is_lag_master(upper)) { NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type"); return -EINVAL; }
- if (!info->linking) + if (!cu_info->linking) break;
if (netdev_has_any_upper_dev(upper)) { @@ -732,7 +736,7 @@ static int prestera_netdev_port_event(struct net_device *lower, }
if (netif_is_lag_master(upper) && - !prestera_lag_master_check(upper, info->upper_info, extack)) + !prestera_lag_master_check(upper, cu_info->upper_info, extack)) return -EOPNOTSUPP; if (netif_is_lag_master(upper) && vlan_uses_dev(dev)) { NL_SET_ERR_MSG_MOD(extack, @@ -748,14 +752,15 @@ static int prestera_netdev_port_event(struct net_device *lower, break;
case NETDEV_CHANGEUPPER: + upper = cu_info->upper_dev; if (netif_is_bridge_master(upper)) { - if (info->linking) + if (cu_info->linking) return prestera_bridge_port_join(upper, port, extack); else prestera_bridge_port_leave(upper, port); } else if (netif_is_lag_master(upper)) { - if (info->linking) + if (cu_info->linking) return prestera_lag_port_add(port, upper); else prestera_lag_port_del(port);