Link: https://syzkaller.appspot.com/bug?id=1724d278c83ca6e6df100a2e320c10d991cf2bce [2]
Reported-by: syzbot <syzbot+355f8edb2ff45d5f95fa@xxxxxxxxxxxxxxxxxxxxxxxxx>
Reported-by: syzbot <syzbot+0f1827363a305f74996f@xxxxxxxxxxxxxxxxxxxxxxxxx>
Tested-by: syzbot <syzbot+355f8edb2ff45d5f95fa@xxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
---
net/can/bcm.c | 79 +++++++++++++++++++++++++++++++++++++++--------
net/can/isotp.c | 82 +++++++++++++++++++++++++++++++++++++++++--------
net/can/raw.c | 82 ++++++++++++++++++++++++++++++++++++++++---------
3 files changed, 203 insertions(+), 40 deletions(-)
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 909b9e684e04..d503abd020ab 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -121,11 +121,18 @@ struct bcm_op {
struct net_device *rx_reg_dev;
};
+struct bcm_notifier_block {
+ /* Linked to bcm_notifier_list list. Becomes empty when removed. */
+ struct list_head list;
+ /* Notifier call is in progress when this value is 0. */
+ unsigned int sequence;
+};
+
struct bcm_sock {
struct sock sk;
int bound;
int ifindex;
- struct notifier_block notifier;
+ struct bcm_notifier_block notifier;
struct list_head rx_ops;
struct list_head tx_ops;
unsigned long dropped_usr_msgs;
@@ -133,6 +140,11 @@ struct bcm_sock {
char procname [32]; /* inode number in decimal with \0 */
};
+static DECLARE_WAIT_QUEUE_HEAD(bcm_notifier_wait);
+static LIST_HEAD(bcm_notifier_list);
+static DEFINE_SPINLOCK(bcm_notifier_lock);
+static unsigned int bcm_notifier_sequence = 1; /* Cannot become 0. */
+
static inline struct bcm_sock *bcm_sk(const struct sock *sk)
{
return (struct bcm_sock *)sk;
@@ -1378,20 +1390,15 @@ static int bcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
/*
* notification handler for netdevice status changes
*/
-static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
- void *ptr)
+static void bcm_notify(struct bcm_sock *bo, unsigned long msg,
+ struct net_device *dev)
{
- struct net_device *dev = netdev_notifier_info_to_dev(ptr);
- struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
struct sock *sk = &bo->sk;
struct bcm_op *op;
int notify_enodev = 0;
if (!net_eq(dev_net(dev), sock_net(sk)))
- return NOTIFY_DONE;
-
- if (dev->type != ARPHRD_CAN)
- return NOTIFY_DONE;
+ return;
switch (msg) {
@@ -1426,7 +1433,43 @@ static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
sk->sk_error_report(sk);
}
}
+}
+static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
+ void *ptr)
+{
+ struct bcm_notifier_block *notify;
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+
+ spin_lock(&bcm_notifier_lock);
+ if (unlikely(!++bcm_notifier_sequence))
+ bcm_notifier_sequence = 1;
+ restart:
+ list_for_each_entry(notify, &bcm_notifier_list, list) {
+ if (unlikely(notify->sequence == bcm_notifier_sequence))
+ continue;
+ notify->sequence = 0;
+ spin_unlock(&bcm_notifier_lock);
+ bcm_notify(container_of(notify, struct bcm_sock, notifier),
+ msg, dev);
+ spin_lock(&bcm_notifier_lock);
+ notify->sequence = bcm_notifier_sequence;
+ /*
+ * If bcm_release() did not remove this entry while we were at
+ * bcm_notify(), we can continue list traversal. Otherwise,
+ * tell bcm_release() that the sequence number became non-zero,
+ * and then restart list traversal. The sequence number also
+ * protects us from calling bcm_notify() for more than once.
+ */
+ if (likely(!list_empty(¬ify->list)))
+ continue;
+ wake_up_all(&bcm_notifier_wait);
+ goto restart;
+ }
+ spin_unlock(&bcm_notifier_lock);
return NOTIFY_DONE;
}
@@ -1446,9 +1489,10 @@ static int bcm_init(struct sock *sk)
INIT_LIST_HEAD(&bo->rx_ops);
/* set notifier */
- bo->notifier.notifier_call = bcm_notifier;
-
- register_netdevice_notifier(&bo->notifier);
+ spin_lock(&bcm_notifier_lock);
+ bo->notifier.sequence = bcm_notifier_sequence;
+ list_add_tail(&bo->notifier.list, &bcm_notifier_list);
+ spin_unlock(&bcm_notifier_lock);
return 0;
}
@@ -1471,7 +1515,10 @@ static int bcm_release(struct socket *sock)
/* remove bcm_ops, timer, rx_unregister(), etc. */
- unregister_netdevice_notifier(&bo->notifier);
+ spin_lock(&bcm_notifier_lock);
+ list_del_init(&bo->notifier.list);
+ spin_unlock(&bcm_notifier_lock);
+ wait_event(bcm_notifier_wait, bo->notifier.sequence);
lock_sock(sk);
@@ -1692,6 +1739,10 @@ static struct pernet_operations canbcm_pernet_ops __read_mostly = {
.exit = canbcm_pernet_exit,
};
+static struct notifier_block canbcm_notifier = {
+ .notifier_call = bcm_notifier
+};
+
static int __init bcm_module_init(void)
{
int err;
@@ -1705,12 +1756,14 @@ static int __init bcm_module_init(void)
}
register_pernet_subsys(&canbcm_pernet_ops);
+ register_netdevice_notifier(&canbcm_notifier);
return 0;
}
static void __exit bcm_module_exit(void)
{
can_proto_unregister(&bcm_can_proto);
+ unregister_netdevice_notifier(&canbcm_notifier);
unregister_pernet_subsys(&canbcm_pernet_ops);
}
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 253b24417c8e..4e41babb81b7 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -128,6 +128,13 @@ struct tpcon {
u8 buf[MAX_MSG_LENGTH + 1];
};
+struct isotp_notifier_block {
+ /* Linked to isotp_notifier_list list. Becomes empty when removed. */
+ struct list_head list;
+ /* Notifier call is in progress when this value is 0. */
+ unsigned int sequence;
+};
+
struct isotp_sock {
struct sock sk;
int bound;
@@ -143,10 +150,15 @@ struct isotp_sock {
u32 force_tx_stmin;
u32 force_rx_stmin;
struct tpcon rx, tx;
- struct notifier_block notifier;
+ struct isotp_notifier_block notifier;
wait_queue_head_t wait;
};
+static DECLARE_WAIT_QUEUE_HEAD(isotp_notifier_wait);
+static LIST_HEAD(isotp_notifier_list);
+static DEFINE_SPINLOCK(isotp_notifier_lock);
+static unsigned int isotp_notifier_sequence = 1; /* Cannot become 0. */
+
static inline struct isotp_sock *isotp_sk(const struct sock *sk)
{
return (struct isotp_sock *)sk;
@@ -1013,7 +1025,10 @@ static int isotp_release(struct socket *sock)
/* wait for complete transmission of current pdu */
wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
- unregister_netdevice_notifier(&so->notifier);
+ spin_lock(&isotp_notifier_lock);
+ list_del_init(&so->notifier.list);
+ spin_unlock(&isotp_notifier_lock);
+ wait_event(isotp_notifier_wait, so->notifier.sequence);
lock_sock(sk);
@@ -1317,21 +1332,16 @@ static int isotp_getsockopt(struct socket *sock, int level, int optname,
return 0;
}
-static int isotp_notifier(struct notifier_block *nb, unsigned long msg,
- void *ptr)
+static void isotp_notify(struct isotp_sock *so, unsigned long msg,
+ struct net_device *dev)
{
- struct net_device *dev = netdev_notifier_info_to_dev(ptr);
- struct isotp_sock *so = container_of(nb, struct isotp_sock, notifier);
struct sock *sk = &so->sk;
if (!net_eq(dev_net(dev), sock_net(sk)))
- return NOTIFY_DONE;
-
- if (dev->type != ARPHRD_CAN)
- return NOTIFY_DONE;
+ return;
if (so->ifindex != dev->ifindex)
- return NOTIFY_DONE;
+ return;
switch (msg) {
case NETDEV_UNREGISTER:
@@ -1357,7 +1367,44 @@ static int isotp_notifier(struct notifier_block *nb, unsigned long msg,
sk->sk_error_report(sk);
break;
}
+}
+static int isotp_notifier(struct notifier_block *nb, unsigned long msg,
+ void *ptr)
+{
+ struct isotp_notifier_block *notify;
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+
+ spin_lock(&isotp_notifier_lock);
+ if (unlikely(!++isotp_notifier_sequence))
+ isotp_notifier_sequence = 1;
+ restart:
+ list_for_each_entry(notify, &isotp_notifier_list, list) {
+ if (unlikely(notify->sequence == isotp_notifier_sequence))
+ continue;
+ notify->sequence = 0;
+ spin_unlock(&isotp_notifier_lock);
+ isotp_notify(container_of(notify, struct isotp_sock, notifier),
+ msg, dev);
+ spin_lock(&isotp_notifier_lock);
+ notify->sequence = isotp_notifier_sequence;
+ /*
+ * If isotp_release() did not remove this entry while we were
+ * at isotp_notify(), we can continue list traversal.
+ * Otherwise, tell isotp_release() that the sequence number
+ * became non-zero, and then restart list traversal. The
+ * sequence number also protects us from calling isotp_notify()
+ * for more than once.
+ */
+ if (likely(!list_empty(¬ify->list)))
+ continue;
+ wake_up_all(&isotp_notifier_wait);
+ goto restart;
+ }
+ spin_unlock(&isotp_notifier_lock);
return NOTIFY_DONE;
}
@@ -1394,8 +1441,10 @@ static int isotp_init(struct sock *sk)
init_waitqueue_head(&so->wait);
- so->notifier.notifier_call = isotp_notifier;
- register_netdevice_notifier(&so->notifier);
+ spin_lock(&isotp_notifier_lock);
+ so->notifier.sequence = isotp_notifier_sequence;
+ list_add_tail(&so->notifier.list, &isotp_notifier_list);
+ spin_unlock(&isotp_notifier_lock);
return 0;
}
@@ -1442,6 +1491,10 @@ static const struct can_proto isotp_can_proto = {
.prot = &isotp_proto,
};
+static struct notifier_block canisotp_notifier = {
+ .notifier_call = isotp_notifier
+};
+
static __init int isotp_module_init(void)
{
int err;
@@ -1451,6 +1504,8 @@ static __init int isotp_module_init(void)
err = can_proto_register(&isotp_can_proto);
if (err < 0)
pr_err("can: registration of isotp protocol failed\n");
+ else
+ register_netdevice_notifier(&canisotp_notifier);
return err;
}
@@ -1458,6 +1513,7 @@ static __init int isotp_module_init(void)
static __exit void isotp_module_exit(void)
{
can_proto_unregister(&isotp_can_proto);
+ unregister_netdevice_notifier(&canisotp_notifier);
}
module_init(isotp_module_init);
diff --git a/net/can/raw.c b/net/can/raw.c
index 139d9471ddcf..f9cdd8698dec 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -79,11 +79,18 @@ struct uniqframe {
unsigned int join_rx_count;
};
+struct raw_notifier_block {
+ /* Linked to raw_notifier_list list. Becomes empty when removed. */
+ struct list_head list;
+ /* Notifier call is in progress when this value is 0. */
+ unsigned int sequence;
+};
+
struct raw_sock {
struct sock sk;
int bound;
int ifindex;
- struct notifier_block notifier;
+ struct raw_notifier_block notifier;
int loopback;
int recv_own_msgs;
int fd_frames;
@@ -95,6 +102,11 @@ struct raw_sock {
struct uniqframe __percpu *uniq;
};
+static DECLARE_WAIT_QUEUE_HEAD(raw_notifier_wait);
+static LIST_HEAD(raw_notifier_list);
+static DEFINE_SPINLOCK(raw_notifier_lock);
+static unsigned int raw_notifier_sequence = 1; /* Cannot become 0. */
+
/* Return pointer to store the extra msg flags for raw_recvmsg().
* We use the space of one unsigned int beyond the 'struct sockaddr_can'
* in skb->cb.
@@ -263,21 +275,16 @@ static int raw_enable_allfilters(struct net *net, struct net_device *dev,
return err;
}
-static int raw_notifier(struct notifier_block *nb,
- unsigned long msg, void *ptr)
+static void raw_notify(struct raw_sock *ro, unsigned long msg,
+ struct net_device *dev)
{
- struct net_device *dev = netdev_notifier_info_to_dev(ptr);
- struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
struct sock *sk = &ro->sk;
if (!net_eq(dev_net(dev), sock_net(sk)))
- return NOTIFY_DONE;
-
- if (dev->type != ARPHRD_CAN)
- return NOTIFY_DONE;
+ return;
if (ro->ifindex != dev->ifindex)
- return NOTIFY_DONE;
+ return;
switch (msg) {
case NETDEV_UNREGISTER:
@@ -305,7 +312,43 @@ static int raw_notifier(struct notifier_block *nb,
sk->sk_error_report(sk);
break;
}
+}
+static int raw_notifier(struct notifier_block *nb, unsigned long msg,
+ void *ptr)
+{
+ struct raw_notifier_block *notify;
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+
+ spin_lock(&raw_notifier_lock);
+ if (unlikely(!++raw_notifier_sequence))
+ raw_notifier_sequence = 1;
+ restart:
+ list_for_each_entry(notify, &raw_notifier_list, list) {
+ if (unlikely(notify->sequence == raw_notifier_sequence))
+ continue;
+ notify->sequence = 0;
+ spin_unlock(&raw_notifier_lock);
+ raw_notify(container_of(notify, struct raw_sock, notifier),
+ msg, dev);
+ spin_lock(&raw_notifier_lock);
+ notify->sequence = raw_notifier_sequence;
+ /*
+ * If raw_release() did not remove this entry while we were at
+ * raw_notify(), we can continue list traversal. Otherwise,
+ * tell raw_release() that the sequence number became non-zero,
+ * and then restart list traversal. The sequence number also
+ * protects us from calling raw_notify() for more than once.
+ */
+ if (likely(!list_empty(¬ify->list)))
+ continue;
+ wake_up_all(&raw_notifier_wait);
+ goto restart;
+ }
+ spin_unlock(&raw_notifier_lock);
return NOTIFY_DONE;
}
@@ -334,9 +377,10 @@ static int raw_init(struct sock *sk)
return -ENOMEM;
/* set notifier */
- ro->notifier.notifier_call = raw_notifier;
-
- register_netdevice_notifier(&ro->notifier);
+ spin_lock(&raw_notifier_lock);
+ ro->notifier.sequence = raw_notifier_sequence;
+ list_add_tail(&ro->notifier.list, &raw_notifier_list);
+ spin_unlock(&raw_notifier_lock);
return 0;
}
@@ -351,7 +395,10 @@ static int raw_release(struct socket *sock)
ro = raw_sk(sk);
- unregister_netdevice_notifier(&ro->notifier);
+ spin_lock(&raw_notifier_lock);
+ list_del_init(&ro->notifier.list);
+ spin_unlock(&raw_notifier_lock);
+ wait_event(raw_notifier_wait, ro->notifier.sequence);
lock_sock(sk);
@@ -889,6 +936,10 @@ static const struct can_proto raw_can_proto = {
.prot = &raw_proto,
};
+static struct notifier_block canraw_notifier = {
+ .notifier_call = raw_notifier
+};
+
static __init int raw_module_init(void)
{
int err;
@@ -898,6 +949,8 @@ static __init int raw_module_init(void)
err = can_proto_register(&raw_can_proto);
if (err < 0)
pr_err("can: registration of raw protocol failed\n");
+ else
+ register_netdevice_notifier(&canraw_notifier);
return err;
}
@@ -905,6 +958,7 @@ static __init int raw_module_init(void)
static __exit void raw_module_exit(void)
{
can_proto_unregister(&raw_can_proto);
+ unregister_netdevice_notifier(&canraw_notifier);
}
module_init(raw_module_init);
