brain-hackers_pepepper-mirror
/
linux-brain
mirror of https://github.com/brain-hackers/linux-brain.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

net: introduce CAN specific pointer in the struct net_device 

[ Upstream commit 4e096a18867a5a989b510f6999d9c6b6622e8f7b ]

Since 20dd3850bc ("can: Speed up CAN frame receiption by using
ml_priv") the CAN framework uses per device specific data in the AF_CAN
protocol. For this purpose the struct net_device->ml_priv is used. Later
the ml_priv usage in CAN was extended for other users, one of them being
CAN_J1939.

Later in the kernel ml_priv was converted to an union, used by other
drivers. E.g. the tun driver started storing it's stats pointer.

Since tun devices can claim to be a CAN device, CAN specific protocols
will wrongly interpret this pointer, which will cause system crashes.
Mostly this issue is visible in the CAN_J1939 stack.

To fix this issue, we request a dedicated CAN pointer within the
net_device struct.

Reported-by: syzbot+5138c4dd15a0401bec7b@syzkaller.appspotmail.com
Fixes: 20dd3850bc ("can: Speed up CAN frame receiption by using ml_priv")
Fixes: ffd956eef6 ("can: introduce CAN midlayer private and allocate it automatically")
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Fixes: 497a5757ce4e ("tun: switch to net core provided statistics counters")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Oleksij Rempel 2021-02-23 08:01:26 +01:00 committed by Greg Kroah-Hartman
parent 23394679aa
commit 4ac1feff6e
10 changed files with 84 additions and 66 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/net/can/dev/dev.c
View File

@ -718,6 +718,7 @@ EXPORT_SYMBOL_GPL(alloc_can_err_skb);
struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
unsigned int txqs, unsigned int rxqs)
{
struct can_ml_priv *can_ml;
struct net_device *dev;
struct can_priv *priv;
int size;
@ -749,7 +750,8 @@ struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
priv = netdev_priv(dev);
priv->dev = dev;
dev->ml_priv = (void *)priv + ALIGN(sizeof_priv, NETDEV_ALIGN);
can_ml = (void *)priv + ALIGN(sizeof_priv, NETDEV_ALIGN);
can_set_ml_priv(dev, can_ml);
if (echo_skb_max) {
priv->echo_skb_max = echo_skb_max;

4
drivers/net/can/slcan.c
View File

@ -519,6 +519,7 @@ static struct slcan *slc_alloc(void)
int i;
char name[IFNAMSIZ];
struct net_device *dev = NULL;
struct can_ml_priv *can_ml;
struct slcan *sl;
int size;
@ -541,7 +542,8 @@ static struct slcan *slc_alloc(void)
dev->base_addr = i;
sl = netdev_priv(dev);
dev->ml_priv = (void *)sl + ALIGN(sizeof(*sl), NETDEV_ALIGN);
can_ml = (void *)sl + ALIGN(sizeof(*sl), NETDEV_ALIGN);
can_set_ml_priv(dev, can_ml);
/* Initialize channel control data */
sl->magic = SLCAN_MAGIC;

2
drivers/net/can/vcan.c
View File

@ -153,7 +153,7 @@ static void vcan_setup(struct net_device *dev)
dev->addr_len = 0;
dev->tx_queue_len = 0;
dev->flags = IFF_NOARP;
dev->ml_priv = netdev_priv(dev);
can_set_ml_priv(dev, netdev_priv(dev));
/* set flags according to driver capabilities */
if (echo)

6
drivers/net/can/vxcan.c
View File

@ -141,6 +141,8 @@ static const struct net_device_ops vxcan_netdev_ops = {
static void vxcan_setup(struct net_device *dev)
{
struct can_ml_priv *can_ml;
dev->type = ARPHRD_CAN;
dev->mtu = CANFD_MTU;
dev->hard_header_len = 0;
@ -149,7 +151,9 @@ static void vxcan_setup(struct net_device *dev)
dev->flags = (IFF_NOARP|IFF_ECHO);
dev->netdev_ops = &vxcan_netdev_ops;
dev->needs_free_netdev = true;
dev->ml_priv = netdev_priv(dev) + ALIGN(sizeof(struct vxcan_priv), NETDEV_ALIGN);
can_ml = netdev_priv(dev) + ALIGN(sizeof(struct vxcan_priv), NETDEV_ALIGN);
can_set_ml_priv(dev, can_ml);
}
/* forward declaration for rtnl_create_link() */

12
include/linux/can/can-ml.h
View File

@ -44,6 +44,7 @@
#include <linux/can.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#define CAN_SFF_RCV_ARRAY_SZ (1 << CAN_SFF_ID_BITS)
#define CAN_EFF_RCV_HASH_BITS 10
@ -65,4 +66,15 @@ struct can_ml_priv {
#endif
};
static inline struct can_ml_priv *can_get_ml_priv(struct net_device *dev)
{
return netdev_get_ml_priv(dev, ML_PRIV_CAN);
}
static inline void can_set_ml_priv(struct net_device *dev,
struct can_ml_priv *ml_priv)
{
netdev_set_ml_priv(dev, ml_priv, ML_PRIV_CAN);
}
#endif /* CAN_ML_H */

34
include/linux/netdevice.h
View File

@ -1555,6 +1555,12 @@ enum netdev_priv_flags {
#define IFF_L3MDEV_RX_HANDLER IFF_L3MDEV_RX_HANDLER
#define IFF_LIVE_RENAME_OK IFF_LIVE_RENAME_OK
/* Specifies the type of the struct net_device::ml_priv pointer */
enum netdev_ml_priv_type {
ML_PRIV_NONE,
ML_PRIV_CAN,
};
/**
* struct net_device - The DEVICE structure.
*
@ -1732,6 +1738,7 @@ enum netdev_priv_flags {
* @nd_net: Network namespace this network device is inside
*
* @ml_priv: Mid-layer private
* @ml_priv_type: Mid-layer private type
* @lstats: Loopback statistics
* @tstats: Tunnel statistics
* @dstats: Dummy statistics
@ -2019,8 +2026,10 @@ struct net_device {
possible_net_t nd_net;
/* mid-layer private */
void *ml_priv;
enum netdev_ml_priv_type ml_priv_type;
union {
void *ml_priv;
struct pcpu_lstats __percpu *lstats;
struct pcpu_sw_netstats __percpu *tstats;
struct pcpu_dstats __percpu *dstats;
@ -2167,6 +2176,29 @@ static inline void netdev_reset_rx_headroom(struct net_device *dev)
netdev_set_rx_headroom(dev, -1);
}
static inline void *netdev_get_ml_priv(struct net_device *dev,
enum netdev_ml_priv_type type)
{
if (dev->ml_priv_type != type)
return NULL;
return dev->ml_priv;
}
static inline void netdev_set_ml_priv(struct net_device *dev,
void *ml_priv,
enum netdev_ml_priv_type type)
{
WARN(dev->ml_priv_type && dev->ml_priv_type != type,
"Overwriting already set ml_priv_type (%u) with different ml_priv_type (%u)!\n",
dev->ml_priv_type, type);
WARN(!dev->ml_priv_type && dev->ml_priv,
"Overwriting already set ml_priv and ml_priv_type is ML_PRIV_NONE!\n");
dev->ml_priv = ml_priv;
dev->ml_priv_type = type;
}
/*
* Net namespace inlines
*/

34
net/can/af_can.c
View File

@ -304,8 +304,8 @@ static struct can_dev_rcv_lists *can_dev_rcv_lists_find(struct net *net,
struct net_device *dev)
{
if (dev) {
struct can_ml_priv *ml_priv = dev->ml_priv;
return &ml_priv->dev_rcv_lists;
struct can_ml_priv *can_ml = can_get_ml_priv(dev);
return &can_ml->dev_rcv_lists;
} else {
return net->can.rx_alldev_list;
}
@ -788,25 +788,6 @@ void can_proto_unregister(const struct can_proto *cp)
}
EXPORT_SYMBOL(can_proto_unregister);
/* af_can notifier to create/remove CAN netdevice specific structs */
static int can_notifier(struct notifier_block *nb, unsigned long msg,
void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
if (dev->type != ARPHRD_CAN)
return NOTIFY_DONE;
switch (msg) {
case NETDEV_REGISTER:
WARN(!dev->ml_priv,
"No CAN mid layer private allocated, please fix your driver and use alloc_candev()!\n");
break;
}
return NOTIFY_DONE;
}
static int can_pernet_init(struct net *net)
{
spin_lock_init(&net->can.rcvlists_lock);
@ -874,11 +855,6 @@ static const struct net_proto_family can_family_ops = {
.owner = THIS_MODULE,
};
/* notifier block for netdevice event */
static struct notifier_block can_netdev_notifier __read_mostly = {
.notifier_call = can_notifier,
};
static struct pernet_operations can_pernet_ops __read_mostly = {
.init = can_pernet_init,
.exit = can_pernet_exit,
@ -909,17 +885,12 @@ static __init int can_init(void)
err = sock_register(&can_family_ops);
if (err)
goto out_sock;
err = register_netdevice_notifier(&can_netdev_notifier);
if (err)
goto out_notifier;
dev_add_pack(&can_packet);
dev_add_pack(&canfd_packet);
return 0;
out_notifier:
sock_unregister(PF_CAN);
out_sock:
unregister_pernet_subsys(&can_pernet_ops);
out_pernet:
@ -933,7 +904,6 @@ static __exit void can_exit(void)
/* protocol unregister */
dev_remove_pack(&canfd_packet);
dev_remove_pack(&can_packet);
unregister_netdevice_notifier(&can_netdev_notifier);
sock_unregister(PF_CAN);
unregister_pernet_subsys(&can_pernet_ops);

22
net/can/j1939/main.c
View File

@ -140,9 +140,9 @@ static struct j1939_priv *j1939_priv_create(struct net_device *ndev)
static inline void j1939_priv_set(struct net_device *ndev,
struct j1939_priv *priv)
{
struct can_ml_priv *can_ml_priv = ndev->ml_priv;
struct can_ml_priv *can_ml = can_get_ml_priv(ndev);
can_ml_priv->j1939_priv = priv;
can_ml->j1939_priv = priv;
}
static void __j1939_priv_release(struct kref *kref)
@ -211,12 +211,9 @@ static void __j1939_rx_release(struct kref *kref)
/* get pointer to priv without increasing ref counter */
static inline struct j1939_priv *j1939_ndev_to_priv(struct net_device *ndev)
{
struct can_ml_priv *can_ml_priv = ndev->ml_priv;
struct can_ml_priv *can_ml = can_get_ml_priv(ndev);
if (!can_ml_priv)
return NULL;
return can_ml_priv->j1939_priv;
return can_ml->j1939_priv;
}
static struct j1939_priv *j1939_priv_get_by_ndev_locked(struct net_device *ndev)
@ -225,9 +222,6 @@ static struct j1939_priv *j1939_priv_get_by_ndev_locked(struct net_device *ndev)
lockdep_assert_held(&j1939_netdev_lock);
if (ndev->type != ARPHRD_CAN)
return NULL;
priv = j1939_ndev_to_priv(ndev);
if (priv)
j1939_priv_get(priv);
@ -348,15 +342,16 @@ static int j1939_netdev_notify(struct notifier_block *nb,
unsigned long msg, void *data)
{
struct net_device *ndev = netdev_notifier_info_to_dev(data);
struct can_ml_priv *can_ml = can_get_ml_priv(ndev);
struct j1939_priv *priv;
if (!can_ml)
goto notify_done;
priv = j1939_priv_get_by_ndev(ndev);
if (!priv)
goto notify_done;
if (ndev->type != ARPHRD_CAN)
goto notify_put;
switch (msg) {
case NETDEV_DOWN:
j1939_cancel_active_session(priv, NULL);
@ -365,7 +360,6 @@ static int j1939_netdev_notify(struct notifier_block *nb,
break;
}
notify_put:
j1939_priv_put(priv);
notify_done:

13
net/can/j1939/socket.c
View File

@ -12,6 +12,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/can/can-ml.h>
#include <linux/can/core.h>
#include <linux/can/skb.h>
#include <linux/errqueue.h>
@ -453,6 +454,7 @@ static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
j1939_jsk_del(priv, jsk);
j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa);
} else {
struct can_ml_priv *can_ml;
struct net_device *ndev;
ndev = dev_get_by_index(net, addr->can_ifindex);
@ -461,15 +463,8 @@ static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
goto out_release_sock;
}
if (ndev->type != ARPHRD_CAN) {
dev_put(ndev);
ret = -ENODEV;
goto out_release_sock;
}
if (!ndev->ml_priv) {
netdev_warn_once(ndev,
"No CAN mid layer private allocated, please fix your driver and use alloc_candev()!\n");
can_ml = can_get_ml_priv(ndev);
if (!can_ml) {
dev_put(ndev);
ret = -ENODEV;
goto out_release_sock;

19
net/can/proc.c
View File

@ -329,8 +329,11 @@ static int can_rcvlist_proc_show(struct seq_file *m, void *v)
/* receive list for registered CAN devices */
for_each_netdev_rcu(net, dev) {
if (dev->type == ARPHRD_CAN && dev->ml_priv)
can_rcvlist_proc_show_one(m, idx, dev, dev->ml_priv);
struct can_ml_priv *can_ml = can_get_ml_priv(dev);
if (can_ml)
can_rcvlist_proc_show_one(m, idx, dev,
&can_ml->dev_rcv_lists);
}
rcu_read_unlock();
@ -382,8 +385,10 @@ static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v)
/* sff receive list for registered CAN devices */
for_each_netdev_rcu(net, dev) {
if (dev->type == ARPHRD_CAN && dev->ml_priv) {
dev_rcv_lists = dev->ml_priv;
struct can_ml_priv *can_ml = can_get_ml_priv(dev);
if (can_ml) {
dev_rcv_lists = &can_ml->dev_rcv_lists;
can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff,
ARRAY_SIZE(dev_rcv_lists->rx_sff));
}
@ -413,8 +418,10 @@ static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v)
/* eff receive list for registered CAN devices */
for_each_netdev_rcu(net, dev) {
if (dev->type == ARPHRD_CAN && dev->ml_priv) {
dev_rcv_lists = dev->ml_priv;
struct can_ml_priv *can_ml = can_get_ml_priv(dev);
if (can_ml) {
dev_rcv_lists = &can_ml->dev_rcv_lists;
can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff,
ARRAY_SIZE(dev_rcv_lists->rx_eff));
}