linux/net/caif/chnl_net.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) ST-Ericsson AB 2010
* Authors: Sjur Brendeland
* Daniel Martensson
*/
#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/ip.h>
#include <linux/sched.h>
#include <linux/sockios.h>
#include <linux/caif/if_caif.h>
#include <net/rtnetlink.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfpkt.h>
#include <net/caif/caif_dev.h>
/* GPRS PDP connection has MTU to 1500 */
#define GPRS_PDP_MTU 1500
/* 5 sec. connect timeout */
#define CONNECT_TIMEOUT (5 * HZ)
#define CAIF_NET_DEFAULT_QUEUE_LEN 500
#define UNDEF_CONNID 0xffffffff
/*This list is protected by the rtnl lock. */
static LIST_HEAD(chnl_net_list);
MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("caif");
enum caif_states {
CAIF_CONNECTED = 1,
CAIF_CONNECTING,
CAIF_DISCONNECTED,
CAIF_SHUTDOWN
};
struct chnl_net {
struct cflayer chnl;
struct caif_connect_request conn_req;
struct list_head list_field;
struct net_device *netdev;
char name[256];
wait_queue_head_t netmgmt_wq;
/* Flow status to remember and control the transmission. */
bool flowenabled;
enum caif_states state;
};
static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
{
struct sk_buff *skb;
struct chnl_net *priv;
int pktlen;
const u8 *ip_version;
u8 buf;
priv = container_of(layr, struct chnl_net, chnl);
skb = (struct sk_buff *) cfpkt_tonative(pkt);
/* Get length of CAIF packet. */
pktlen = skb->len;
/* Pass some minimum information and
* send the packet to the net stack.
*/
skb->dev = priv->netdev;
/* check the version of IP */
ip_version = skb_header_pointer(skb, 0, 1, &buf);
if (!ip_version) {
kfree_skb(skb);
return -EINVAL;
}
switch (*ip_version >> 4) {
case 4:
skb->protocol = htons(ETH_P_IP);
break;
case 6:
skb->protocol = htons(ETH_P_IPV6);
break;
default:
kfree_skb(skb);
priv->netdev->stats.rx_errors++;
return -EINVAL;
}
/* If we change the header in loop mode, the checksum is corrupted. */
if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
skb->ip_summed = CHECKSUM_UNNECESSARY;
else
skb->ip_summed = CHECKSUM_NONE;
netif_rx(skb);
/* Update statistics. */
priv->netdev->stats.rx_packets++;
priv->netdev->stats.rx_bytes += pktlen;
return 0;
}
static int delete_device(struct chnl_net *dev)
{
ASSERT_RTNL();
if (dev->netdev)
unregister_netdevice(dev->netdev);
return 0;
}
static void close_work(struct work_struct *work)
{
struct chnl_net *dev = NULL;
struct list_head *list_node;
struct list_head *_tmp;
rtnl_lock();
list_for_each_safe(list_node, _tmp, &chnl_net_list) {
dev = list_entry(list_node, struct chnl_net, list_field);
if (dev->state == CAIF_SHUTDOWN)
dev_close(dev->netdev);
}
rtnl_unlock();
}
static DECLARE_WORK(close_worker, close_work);
static void chnl_hold(struct cflayer *lyr)
{
struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
dev_hold(priv->netdev);
}
static void chnl_put(struct cflayer *lyr)
{
struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
dev_put(priv->netdev);
}
static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
int phyid)
{
struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
pr_debug("NET flowctrl func called flow: %s\n",
flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
"REMOTE_SHUTDOWN" : "UNKNOWN CTRL COMMAND");
switch (flow) {
case CAIF_CTRLCMD_FLOW_OFF_IND:
priv->flowenabled = false;
netif_stop_queue(priv->netdev);
break;
case CAIF_CTRLCMD_DEINIT_RSP:
priv->state = CAIF_DISCONNECTED;
break;
case CAIF_CTRLCMD_INIT_FAIL_RSP:
priv->state = CAIF_DISCONNECTED;
wake_up_interruptible(&priv->netmgmt_wq);
break;
case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
priv->state = CAIF_SHUTDOWN;
netif_tx_disable(priv->netdev);
schedule_work(&close_worker);
break;
case CAIF_CTRLCMD_FLOW_ON_IND:
priv->flowenabled = true;
netif_wake_queue(priv->netdev);
break;
case CAIF_CTRLCMD_INIT_RSP:
caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
priv->state = CAIF_CONNECTED;
priv->flowenabled = true;
netif_wake_queue(priv->netdev);
wake_up_interruptible(&priv->netmgmt_wq);
break;
default:
break;
}
}
static netdev_tx_t chnl_net_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct chnl_net *priv;
struct cfpkt *pkt = NULL;
int len;
int result = -1;
/* Get our private data. */
priv = netdev_priv(dev);
if (skb->len > priv->netdev->mtu) {
pr_warn("Size of skb exceeded MTU\n");
kfree_skb(skb);
dev->stats.tx_errors++;
return NETDEV_TX_OK;
}
if (!priv->flowenabled) {
pr_debug("dropping packets flow off\n");
kfree_skb(skb);
dev->stats.tx_dropped++;
return NETDEV_TX_OK;
}
if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
/* Store original SKB length. */
len = skb->len;
pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
/* Send the packet down the stack. */
result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
if (result) {
dev->stats.tx_dropped++;
return NETDEV_TX_OK;
}
/* Update statistics. */
dev->stats.tx_packets++;
dev->stats.tx_bytes += len;
return NETDEV_TX_OK;
}
static int chnl_net_open(struct net_device *dev)
{
struct chnl_net *priv = NULL;
int result = -1;
int llifindex, headroom, tailroom, mtu;
struct net_device *lldev;
ASSERT_RTNL();
priv = netdev_priv(dev);
if (!priv) {
pr_debug("chnl_net_open: no priv\n");
return -ENODEV;
}
if (priv->state != CAIF_CONNECTING) {
priv->state = CAIF_CONNECTING;
result = caif_connect_client(dev_net(dev), &priv->conn_req,
&priv->chnl, &llifindex,
&headroom, &tailroom);
if (result != 0) {
pr_debug("err: "
"Unable to register and open device,"
" Err:%d\n",
result);
goto error;
}
lldev = __dev_get_by_index(dev_net(dev), llifindex);
if (lldev == NULL) {
pr_debug("no interface?\n");
result = -ENODEV;
goto error;
}
dev->needed_tailroom = tailroom + lldev->needed_tailroom;
dev->hard_header_len = headroom + lldev->hard_header_len +
lldev->needed_tailroom;
/*
* MTU, head-room etc is not know before we have a
* CAIF link layer device available. MTU calculation may
* override initial RTNL configuration.
* MTU is minimum of current mtu, link layer mtu pluss
* CAIF head and tail, and PDP GPRS contexts max MTU.
*/
mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
mtu = min_t(int, GPRS_PDP_MTU, mtu);
dev_set_mtu(dev, mtu);
if (mtu < 100) {
pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
result = -ENODEV;
goto error;
}
}
rtnl_unlock(); /* Release RTNL lock during connect wait */
result = wait_event_interruptible_timeout(priv->netmgmt_wq,
priv->state != CAIF_CONNECTING,
CONNECT_TIMEOUT);
rtnl_lock();
if (result == -ERESTARTSYS) {
pr_debug("wait_event_interruptible woken by a signal\n");
result = -ERESTARTSYS;
goto error;
}
if (result == 0) {
pr_debug("connect timeout\n");
caif_disconnect_client(dev_net(dev), &priv->chnl);
priv->state = CAIF_DISCONNECTED;
pr_debug("state disconnected\n");
result = -ETIMEDOUT;
goto error;
}
if (priv->state != CAIF_CONNECTED) {
pr_debug("connect failed\n");
result = -ECONNREFUSED;
goto error;
}
pr_debug("CAIF Netdevice connected\n");
return 0;
error:
caif_disconnect_client(dev_net(dev), &priv->chnl);
priv->state = CAIF_DISCONNECTED;
pr_debug("state disconnected\n");
return result;
}
static int chnl_net_stop(struct net_device *dev)
{
struct chnl_net *priv;
ASSERT_RTNL();
priv = netdev_priv(dev);
priv->state = CAIF_DISCONNECTED;
caif_disconnect_client(dev_net(dev), &priv->chnl);
return 0;
}
static int chnl_net_init(struct net_device *dev)
{
struct chnl_net *priv;
ASSERT_RTNL();
priv = netdev_priv(dev);
strncpy(priv->name, dev->name, sizeof(priv->name));
net-caif: avoid user-triggerable WARN_ON(1) syszbot triggers this warning, which looks something we can easily prevent. If we initialize priv->list_field in chnl_net_init(), then always use list_del_init(), we can remove robust_list_del() completely. WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 robust_list_del net/caif/chnl_net.c:67 [inline] WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Modules linked in: CPU: 0 PID: 3233 Comm: syz-executor.3 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:robust_list_del net/caif/chnl_net.c:67 [inline] RIP: 0010:chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Code: 89 eb e8 3a a3 ba f8 48 89 d8 48 c1 e8 03 42 80 3c 28 00 0f 85 bf 01 00 00 48 81 fb 00 14 4e 8d 48 8b 2b 75 d0 e8 17 a3 ba f8 <0f> 0b 5b 5d 41 5c 41 5d e9 0a a3 ba f8 4c 89 e3 e8 02 a3 ba f8 4c RSP: 0018:ffffc90009067248 EFLAGS: 00010202 RAX: 0000000000008780 RBX: ffffffff8d4e1400 RCX: ffffc9000fd34000 RDX: 0000000000040000 RSI: ffffffff88bb6e49 RDI: 0000000000000003 RBP: ffff88802cd9ee08 R08: 0000000000000000 R09: ffffffff8d0e6647 R10: ffffffff88bb6dc2 R11: 0000000000000000 R12: ffff88803791ae08 R13: dffffc0000000000 R14: 00000000e600ffce R15: ffff888073ed3480 FS: 00007fed10fa0700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c322000 CR3: 00000000164a6000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: register_netdevice+0xadf/0x1500 net/core/dev.c:10347 ipcaif_newlink+0x4c/0x260 net/caif/chnl_net.c:468 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 __sys_sendto+0x21c/0x320 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: cc36a070b590 ("net-caif: add CAIF netdevice") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-13 18:08:36 +00:00
INIT_LIST_HEAD(&priv->list_field);
return 0;
}
static void chnl_net_uninit(struct net_device *dev)
{
struct chnl_net *priv;
ASSERT_RTNL();
priv = netdev_priv(dev);
net-caif: avoid user-triggerable WARN_ON(1) syszbot triggers this warning, which looks something we can easily prevent. If we initialize priv->list_field in chnl_net_init(), then always use list_del_init(), we can remove robust_list_del() completely. WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 robust_list_del net/caif/chnl_net.c:67 [inline] WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Modules linked in: CPU: 0 PID: 3233 Comm: syz-executor.3 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:robust_list_del net/caif/chnl_net.c:67 [inline] RIP: 0010:chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Code: 89 eb e8 3a a3 ba f8 48 89 d8 48 c1 e8 03 42 80 3c 28 00 0f 85 bf 01 00 00 48 81 fb 00 14 4e 8d 48 8b 2b 75 d0 e8 17 a3 ba f8 <0f> 0b 5b 5d 41 5c 41 5d e9 0a a3 ba f8 4c 89 e3 e8 02 a3 ba f8 4c RSP: 0018:ffffc90009067248 EFLAGS: 00010202 RAX: 0000000000008780 RBX: ffffffff8d4e1400 RCX: ffffc9000fd34000 RDX: 0000000000040000 RSI: ffffffff88bb6e49 RDI: 0000000000000003 RBP: ffff88802cd9ee08 R08: 0000000000000000 R09: ffffffff8d0e6647 R10: ffffffff88bb6dc2 R11: 0000000000000000 R12: ffff88803791ae08 R13: dffffc0000000000 R14: 00000000e600ffce R15: ffff888073ed3480 FS: 00007fed10fa0700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c322000 CR3: 00000000164a6000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: register_netdevice+0xadf/0x1500 net/core/dev.c:10347 ipcaif_newlink+0x4c/0x260 net/caif/chnl_net.c:468 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 __sys_sendto+0x21c/0x320 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: cc36a070b590 ("net-caif: add CAIF netdevice") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-13 18:08:36 +00:00
list_del_init(&priv->list_field);
}
static const struct net_device_ops netdev_ops = {
.ndo_open = chnl_net_open,
.ndo_stop = chnl_net_stop,
.ndo_init = chnl_net_init,
.ndo_uninit = chnl_net_uninit,
.ndo_start_xmit = chnl_net_start_xmit,
};
static void chnl_net_destructor(struct net_device *dev)
{
struct chnl_net *priv = netdev_priv(dev);
caif_free_client(&priv->chnl);
}
static void ipcaif_net_setup(struct net_device *dev)
{
struct chnl_net *priv;
dev->netdev_ops = &netdev_ops;
net: Fix inconsistent teardown and release of private netdev state. Network devices can allocate reasources and private memory using netdev_ops->ndo_init(). However, the release of these resources can occur in one of two different places. Either netdev_ops->ndo_uninit() or netdev->destructor(). The decision of which operation frees the resources depends upon whether it is necessary for all netdev refs to be released before it is safe to perform the freeing. netdev_ops->ndo_uninit() presumably can occur right after the NETDEV_UNREGISTER notifier completes and the unicast and multicast address lists are flushed. netdev->destructor(), on the other hand, does not run until the netdev references all go away. Further complicating the situation is that netdev->destructor() almost universally does also a free_netdev(). This creates a problem for the logic in register_netdevice(). Because all callers of register_netdevice() manage the freeing of the netdev, and invoke free_netdev(dev) if register_netdevice() fails. If netdev_ops->ndo_init() succeeds, but something else fails inside of register_netdevice(), it does call ndo_ops->ndo_uninit(). But it is not able to invoke netdev->destructor(). This is because netdev->destructor() will do a free_netdev() and then the caller of register_netdevice() will do the same. However, this means that the resources that would normally be released by netdev->destructor() will not be. Over the years drivers have added local hacks to deal with this, by invoking their destructor parts by hand when register_netdevice() fails. Many drivers do not try to deal with this, and instead we have leaks. Let's close this hole by formalizing the distinction between what private things need to be freed up by netdev->destructor() and whether the driver needs unregister_netdevice() to perform the free_netdev(). netdev->priv_destructor() performs all actions to free up the private resources that used to be freed by netdev->destructor(), except for free_netdev(). netdev->needs_free_netdev is a boolean that indicates whether free_netdev() should be done at the end of unregister_netdevice(). Now, register_netdevice() can sanely release all resources after ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit() and netdev->priv_destructor(). And at the end of unregister_netdevice(), we invoke netdev->priv_destructor() and optionally call free_netdev(). Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-08 16:52:56 +00:00
dev->needs_free_netdev = true;
dev->priv_destructor = chnl_net_destructor;
dev->flags |= IFF_NOARP;
dev->flags |= IFF_POINTOPOINT;
dev->mtu = GPRS_PDP_MTU;
dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
priv = netdev_priv(dev);
priv->chnl.receive = chnl_recv_cb;
priv->chnl.ctrlcmd = chnl_flowctrl_cb;
priv->netdev = dev;
priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
priv->conn_req.priority = CAIF_PRIO_LOW;
/* Insert illegal value */
priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
priv->flowenabled = false;
init_waitqueue_head(&priv->netmgmt_wq);
}
static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct chnl_net *priv;
u8 loop;
priv = netdev_priv(dev);
if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
priv->conn_req.sockaddr.u.dgm.connection_id) ||
nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
priv->conn_req.sockaddr.u.dgm.connection_id))
goto nla_put_failure;
loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static void caif_netlink_parms(struct nlattr *data[],
struct caif_connect_request *conn_req)
{
if (!data) {
pr_warn("no params data found\n");
return;
}
if (data[IFLA_CAIF_IPV4_CONNID])
conn_req->sockaddr.u.dgm.connection_id =
nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
if (data[IFLA_CAIF_IPV6_CONNID])
conn_req->sockaddr.u.dgm.connection_id =
nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
if (data[IFLA_CAIF_LOOPBACK]) {
if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
else
conn_req->protocol = CAIFPROTO_DATAGRAM;
}
}
static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
int ret;
struct chnl_net *caifdev;
ASSERT_RTNL();
caifdev = netdev_priv(dev);
caif_netlink_parms(data, &caifdev->conn_req);
ret = register_netdevice(dev);
if (ret)
pr_warn("device rtml registration failed\n");
else
list_add(&caifdev->list_field, &chnl_net_list);
/* Use ifindex as connection id, and use loopback channel default. */
if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
}
return ret;
}
static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct chnl_net *caifdev;
ASSERT_RTNL();
caifdev = netdev_priv(dev);
caif_netlink_parms(data, &caifdev->conn_req);
netdev_state_change(dev);
return 0;
}
static size_t ipcaif_get_size(const struct net_device *dev)
{
return
/* IFLA_CAIF_IPV4_CONNID */
nla_total_size(4) +
/* IFLA_CAIF_IPV6_CONNID */
nla_total_size(4) +
/* IFLA_CAIF_LOOPBACK */
nla_total_size(2) +
0;
}
static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
[IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 },
[IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 },
[IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 }
};
static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
.kind = "caif",
.priv_size = sizeof(struct chnl_net),
.setup = ipcaif_net_setup,
.maxtype = IFLA_CAIF_MAX,
.policy = ipcaif_policy,
.newlink = ipcaif_newlink,
.changelink = ipcaif_changelink,
.get_size = ipcaif_get_size,
.fill_info = ipcaif_fill_info,
};
static int __init chnl_init_module(void)
{
return rtnl_link_register(&ipcaif_link_ops);
}
static void __exit chnl_exit_module(void)
{
struct chnl_net *dev = NULL;
struct list_head *list_node;
struct list_head *_tmp;
rtnl_link_unregister(&ipcaif_link_ops);
rtnl_lock();
list_for_each_safe(list_node, _tmp, &chnl_net_list) {
dev = list_entry(list_node, struct chnl_net, list_field);
net-caif: avoid user-triggerable WARN_ON(1) syszbot triggers this warning, which looks something we can easily prevent. If we initialize priv->list_field in chnl_net_init(), then always use list_del_init(), we can remove robust_list_del() completely. WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 robust_list_del net/caif/chnl_net.c:67 [inline] WARNING: CPU: 0 PID: 3233 at net/caif/chnl_net.c:67 chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Modules linked in: CPU: 0 PID: 3233 Comm: syz-executor.3 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:robust_list_del net/caif/chnl_net.c:67 [inline] RIP: 0010:chnl_net_uninit+0xc9/0x2e0 net/caif/chnl_net.c:375 Code: 89 eb e8 3a a3 ba f8 48 89 d8 48 c1 e8 03 42 80 3c 28 00 0f 85 bf 01 00 00 48 81 fb 00 14 4e 8d 48 8b 2b 75 d0 e8 17 a3 ba f8 <0f> 0b 5b 5d 41 5c 41 5d e9 0a a3 ba f8 4c 89 e3 e8 02 a3 ba f8 4c RSP: 0018:ffffc90009067248 EFLAGS: 00010202 RAX: 0000000000008780 RBX: ffffffff8d4e1400 RCX: ffffc9000fd34000 RDX: 0000000000040000 RSI: ffffffff88bb6e49 RDI: 0000000000000003 RBP: ffff88802cd9ee08 R08: 0000000000000000 R09: ffffffff8d0e6647 R10: ffffffff88bb6dc2 R11: 0000000000000000 R12: ffff88803791ae08 R13: dffffc0000000000 R14: 00000000e600ffce R15: ffff888073ed3480 FS: 00007fed10fa0700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2c322000 CR3: 00000000164a6000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: register_netdevice+0xadf/0x1500 net/core/dev.c:10347 ipcaif_newlink+0x4c/0x260 net/caif/chnl_net.c:468 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 __sys_sendto+0x21c/0x320 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: cc36a070b590 ("net-caif: add CAIF netdevice") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-13 18:08:36 +00:00
list_del_init(list_node);
delete_device(dev);
}
rtnl_unlock();
}
module_init(chnl_init_module);
module_exit(chnl_exit_module);