* [net 1/4] can: j1939: fix Use-after-Free, hold skb ref while in use
2021-06-16 11:01 pull-request: can 2021-06-16 Marc Kleine-Budde
@ 2021-06-16 11:01 ` Marc Kleine-Budde
2021-06-16 11:01 ` [net 2/4] can: bcm/raw/isotp: use per module netdevice notifier Marc Kleine-Budde
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Marc Kleine-Budde @ 2021-06-16 11:01 UTC (permalink / raw)
To: netdev
Cc: davem, kuba, linux-can, kernel, Oleksij Rempel, Hillf Danton,
linux-stable, syzbot+220c1a29987a9a490903,
syzbot+45199c1b73b4013525cf, Marc Kleine-Budde
From: Oleksij Rempel <o.rempel@pengutronix.de>
This patch fixes a Use-after-Free found by the syzbot.
The problem is that a skb is taken from the per-session skb queue,
without incrementing the ref count. This leads to a Use-after-Free if
the skb is taken concurrently from the session queue due to a CTS.
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Link: https://lore.kernel.org/r/20210521115720.7533-1-o.rempel@pengutronix.de
Cc: Hillf Danton <hdanton@sina.com>
Cc: linux-stable <stable@vger.kernel.org>
Reported-by: syzbot+220c1a29987a9a490903@syzkaller.appspotmail.com
Reported-by: syzbot+45199c1b73b4013525cf@syzkaller.appspotmail.com
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
net/can/j1939/transport.c | 54 +++++++++++++++++++++++++++++----------
1 file changed, 40 insertions(+), 14 deletions(-)
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index e09d087ba240..c3946c355882 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -330,6 +330,9 @@ static void j1939_session_skb_drop_old(struct j1939_session *session)
if ((do_skcb->offset + do_skb->len) < offset_start) {
__skb_unlink(do_skb, &session->skb_queue);
+ /* drop ref taken in j1939_session_skb_queue() */
+ skb_unref(do_skb);
+
kfree_skb(do_skb);
}
spin_unlock_irqrestore(&session->skb_queue.lock, flags);
@@ -349,12 +352,13 @@ void j1939_session_skb_queue(struct j1939_session *session,
skcb->flags |= J1939_ECU_LOCAL_SRC;
+ skb_get(skb);
skb_queue_tail(&session->skb_queue, skb);
}
static struct
-sk_buff *j1939_session_skb_find_by_offset(struct j1939_session *session,
- unsigned int offset_start)
+sk_buff *j1939_session_skb_get_by_offset(struct j1939_session *session,
+ unsigned int offset_start)
{
struct j1939_priv *priv = session->priv;
struct j1939_sk_buff_cb *do_skcb;
@@ -371,6 +375,10 @@ sk_buff *j1939_session_skb_find_by_offset(struct j1939_session *session,
skb = do_skb;
}
}
+
+ if (skb)
+ skb_get(skb);
+
spin_unlock_irqrestore(&session->skb_queue.lock, flags);
if (!skb)
@@ -381,12 +389,12 @@ sk_buff *j1939_session_skb_find_by_offset(struct j1939_session *session,
return skb;
}
-static struct sk_buff *j1939_session_skb_find(struct j1939_session *session)
+static struct sk_buff *j1939_session_skb_get(struct j1939_session *session)
{
unsigned int offset_start;
offset_start = session->pkt.dpo * 7;
- return j1939_session_skb_find_by_offset(session, offset_start);
+ return j1939_session_skb_get_by_offset(session, offset_start);
}
/* see if we are receiver
@@ -776,7 +784,7 @@ static int j1939_session_tx_dat(struct j1939_session *session)
int ret = 0;
u8 dat[8];
- se_skb = j1939_session_skb_find_by_offset(session, session->pkt.tx * 7);
+ se_skb = j1939_session_skb_get_by_offset(session, session->pkt.tx * 7);
if (!se_skb)
return -ENOBUFS;
@@ -801,7 +809,8 @@ static int j1939_session_tx_dat(struct j1939_session *session)
netdev_err_once(priv->ndev,
"%s: 0x%p: requested data outside of queued buffer: offset %i, len %i, pkt.tx: %i\n",
__func__, session, skcb->offset, se_skb->len , session->pkt.tx);
- return -EOVERFLOW;
+ ret = -EOVERFLOW;
+ goto out_free;
}
if (!len) {
@@ -835,6 +844,12 @@ static int j1939_session_tx_dat(struct j1939_session *session)
if (pkt_done)
j1939_tp_set_rxtimeout(session, 250);
+ out_free:
+ if (ret)
+ kfree_skb(se_skb);
+ else
+ consume_skb(se_skb);
+
return ret;
}
@@ -1007,7 +1022,7 @@ static int j1939_xtp_txnext_receiver(struct j1939_session *session)
static int j1939_simple_txnext(struct j1939_session *session)
{
struct j1939_priv *priv = session->priv;
- struct sk_buff *se_skb = j1939_session_skb_find(session);
+ struct sk_buff *se_skb = j1939_session_skb_get(session);
struct sk_buff *skb;
int ret;
@@ -1015,8 +1030,10 @@ static int j1939_simple_txnext(struct j1939_session *session)
return 0;
skb = skb_clone(se_skb, GFP_ATOMIC);
- if (!skb)
- return -ENOMEM;
+ if (!skb) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
can_skb_set_owner(skb, se_skb->sk);
@@ -1024,12 +1041,18 @@ static int j1939_simple_txnext(struct j1939_session *session)
ret = j1939_send_one(priv, skb);
if (ret)
- return ret;
+ goto out_free;
j1939_sk_errqueue(session, J1939_ERRQUEUE_SCHED);
j1939_sk_queue_activate_next(session);
- return 0;
+ out_free:
+ if (ret)
+ kfree_skb(se_skb);
+ else
+ consume_skb(se_skb);
+
+ return ret;
}
static bool j1939_session_deactivate_locked(struct j1939_session *session)
@@ -1170,9 +1193,10 @@ static void j1939_session_completed(struct j1939_session *session)
struct sk_buff *skb;
if (!session->transmission) {
- skb = j1939_session_skb_find(session);
+ skb = j1939_session_skb_get(session);
/* distribute among j1939 receivers */
j1939_sk_recv(session->priv, skb);
+ consume_skb(skb);
}
j1939_session_deactivate_activate_next(session);
@@ -1744,7 +1768,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
{
struct j1939_priv *priv = session->priv;
struct j1939_sk_buff_cb *skcb;
- struct sk_buff *se_skb;
+ struct sk_buff *se_skb = NULL;
const u8 *dat;
u8 *tpdat;
int offset;
@@ -1786,7 +1810,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
goto out_session_cancel;
}
- se_skb = j1939_session_skb_find_by_offset(session, packet * 7);
+ se_skb = j1939_session_skb_get_by_offset(session, packet * 7);
if (!se_skb) {
netdev_warn(priv->ndev, "%s: 0x%p: no skb found\n", __func__,
session);
@@ -1848,11 +1872,13 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
j1939_tp_set_rxtimeout(session, 250);
}
session->last_cmd = 0xff;
+ consume_skb(se_skb);
j1939_session_put(session);
return;
out_session_cancel:
+ kfree_skb(se_skb);
j1939_session_timers_cancel(session);
j1939_session_cancel(session, J1939_XTP_ABORT_FAULT);
j1939_session_put(session);
base-commit: a4f0377db1254373513b992ff31a351a7111f0fd
--
2.30.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [net 2/4] can: bcm/raw/isotp: use per module netdevice notifier
2021-06-16 11:01 pull-request: can 2021-06-16 Marc Kleine-Budde
2021-06-16 11:01 ` [net 1/4] can: j1939: fix Use-after-Free, hold skb ref while in use Marc Kleine-Budde
@ 2021-06-16 11:01 ` Marc Kleine-Budde
2021-06-16 11:01 ` [net 3/4] can: bcm: fix infoleak in struct bcm_msg_head Marc Kleine-Budde
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Marc Kleine-Budde @ 2021-06-16 11:01 UTC (permalink / raw)
To: netdev
Cc: davem, kuba, linux-can, kernel, Tetsuo Handa, linux-stable,
syzbot, syzbot, Kirill Tkhai, Oliver Hartkopp, Tetsuo Handa,
Marc Kleine-Budde
From: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
syzbot is reporting hung task at register_netdevice_notifier() [1] and
unregister_netdevice_notifier() [2], for cleanup_net() might perform
time consuming operations while CAN driver's raw/bcm/isotp modules are
calling {register,unregister}_netdevice_notifier() on each socket.
Change raw/bcm/isotp modules to call register_netdevice_notifier() from
module's __init function and call unregister_netdevice_notifier() from
module's __exit function, as with gw/j1939 modules are doing.
Link: https://syzkaller.appspot.com/bug?id=391b9498827788b3cc6830226d4ff5be87107c30 [1]
Link: https://syzkaller.appspot.com/bug?id=1724d278c83ca6e6df100a2e320c10d991cf2bce [2]
Link: https://lore.kernel.org/r/54a5f451-05ed-f977-8534-79e7aa2bcc8f@i-love.sakura.ne.jp
Cc: linux-stable <stable@vger.kernel.org>
Reported-by: syzbot <syzbot+355f8edb2ff45d5f95fa@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+0f1827363a305f74996f@syzkaller.appspotmail.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Tested-by: syzbot <syzbot+355f8edb2ff45d5f95fa@syzkaller.appspotmail.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
net/can/bcm.c | 59 +++++++++++++++++++++++++++++++++++-----------
net/can/isotp.c | 61 +++++++++++++++++++++++++++++++++++++-----------
net/can/raw.c | 62 ++++++++++++++++++++++++++++++++++++++-----------
3 files changed, 142 insertions(+), 40 deletions(-)
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 909b9e684e04..f00176b2a6c3 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -125,7 +125,7 @@ struct bcm_sock {
struct sock sk;
int bound;
int ifindex;
- struct notifier_block notifier;
+ struct list_head notifier;
struct list_head rx_ops;
struct list_head tx_ops;
unsigned long dropped_usr_msgs;
@@ -133,6 +133,10 @@ struct bcm_sock {
char procname [32]; /* inode number in decimal with \0 */
};
+static LIST_HEAD(bcm_notifier_list);
+static DEFINE_SPINLOCK(bcm_notifier_lock);
+static struct bcm_sock *bcm_busy_notifier;
+
static inline struct bcm_sock *bcm_sk(const struct sock *sk)
{
return (struct bcm_sock *)sk;
@@ -1378,20 +1382,15 @@ 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 +1425,28 @@ 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 net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+ if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
+ return NOTIFY_DONE;
+ if (unlikely(bcm_busy_notifier)) /* Check for reentrant bug. */
+ return NOTIFY_DONE;
+
+ spin_lock(&bcm_notifier_lock);
+ list_for_each_entry(bcm_busy_notifier, &bcm_notifier_list, notifier) {
+ spin_unlock(&bcm_notifier_lock);
+ bcm_notify(bcm_busy_notifier, msg, dev);
+ spin_lock(&bcm_notifier_lock);
+ }
+ bcm_busy_notifier = NULL;
+ spin_unlock(&bcm_notifier_lock);
return NOTIFY_DONE;
}
@@ -1446,9 +1466,9 @@ 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);
+ list_add_tail(&bo->notifier, &bcm_notifier_list);
+ spin_unlock(&bcm_notifier_lock);
return 0;
}
@@ -1471,7 +1491,14 @@ static int bcm_release(struct socket *sock)
/* remove bcm_ops, timer, rx_unregister(), etc. */
- unregister_netdevice_notifier(&bo->notifier);
+ spin_lock(&bcm_notifier_lock);
+ while (bcm_busy_notifier == bo) {
+ spin_unlock(&bcm_notifier_lock);
+ schedule_timeout_uninterruptible(1);
+ spin_lock(&bcm_notifier_lock);
+ }
+ list_del(&bo->notifier);
+ spin_unlock(&bcm_notifier_lock);
lock_sock(sk);
@@ -1692,6 +1719,10 @@ 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 +1736,14 @@ 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..be6183f8ca11 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -143,10 +143,14 @@ struct isotp_sock {
u32 force_tx_stmin;
u32 force_rx_stmin;
struct tpcon rx, tx;
- struct notifier_block notifier;
+ struct list_head notifier;
wait_queue_head_t wait;
};
+static LIST_HEAD(isotp_notifier_list);
+static DEFINE_SPINLOCK(isotp_notifier_lock);
+static struct isotp_sock *isotp_busy_notifier;
+
static inline struct isotp_sock *isotp_sk(const struct sock *sk)
{
return (struct isotp_sock *)sk;
@@ -1013,7 +1017,14 @@ 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);
+ while (isotp_busy_notifier == so) {
+ spin_unlock(&isotp_notifier_lock);
+ schedule_timeout_uninterruptible(1);
+ spin_lock(&isotp_notifier_lock);
+ }
+ list_del(&so->notifier);
+ spin_unlock(&isotp_notifier_lock);
lock_sock(sk);
@@ -1317,21 +1328,16 @@ 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 +1363,28 @@ 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 net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+ if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
+ return NOTIFY_DONE;
+ if (unlikely(isotp_busy_notifier)) /* Check for reentrant bug. */
+ return NOTIFY_DONE;
+
+ spin_lock(&isotp_notifier_lock);
+ list_for_each_entry(isotp_busy_notifier, &isotp_notifier_list, notifier) {
+ spin_unlock(&isotp_notifier_lock);
+ isotp_notify(isotp_busy_notifier, msg, dev);
+ spin_lock(&isotp_notifier_lock);
+ }
+ isotp_busy_notifier = NULL;
+ spin_unlock(&isotp_notifier_lock);
return NOTIFY_DONE;
}
@@ -1394,8 +1421,9 @@ 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);
+ list_add_tail(&so->notifier, &isotp_notifier_list);
+ spin_unlock(&isotp_notifier_lock);
return 0;
}
@@ -1442,6 +1470,10 @@ 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 +1483,8 @@ 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 +1492,7 @@ 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..ac96fc210025 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -83,7 +83,7 @@ struct raw_sock {
struct sock sk;
int bound;
int ifindex;
- struct notifier_block notifier;
+ struct list_head notifier;
int loopback;
int recv_own_msgs;
int fd_frames;
@@ -95,6 +95,10 @@ struct raw_sock {
struct uniqframe __percpu *uniq;
};
+static LIST_HEAD(raw_notifier_list);
+static DEFINE_SPINLOCK(raw_notifier_lock);
+static struct raw_sock *raw_busy_notifier;
+
/* 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 +267,16 @@ 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 +304,28 @@ 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 net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (dev->type != ARPHRD_CAN)
+ return NOTIFY_DONE;
+ if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
+ return NOTIFY_DONE;
+ if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */
+ return NOTIFY_DONE;
+ spin_lock(&raw_notifier_lock);
+ list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) {
+ spin_unlock(&raw_notifier_lock);
+ raw_notify(raw_busy_notifier, msg, dev);
+ spin_lock(&raw_notifier_lock);
+ }
+ raw_busy_notifier = NULL;
+ spin_unlock(&raw_notifier_lock);
return NOTIFY_DONE;
}
@@ -334,9 +354,9 @@ 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);
+ list_add_tail(&ro->notifier, &raw_notifier_list);
+ spin_unlock(&raw_notifier_lock);
return 0;
}
@@ -351,7 +371,14 @@ static int raw_release(struct socket *sock)
ro = raw_sk(sk);
- unregister_netdevice_notifier(&ro->notifier);
+ spin_lock(&raw_notifier_lock);
+ while (raw_busy_notifier == ro) {
+ spin_unlock(&raw_notifier_lock);
+ schedule_timeout_uninterruptible(1);
+ spin_lock(&raw_notifier_lock);
+ }
+ list_del(&ro->notifier);
+ spin_unlock(&raw_notifier_lock);
lock_sock(sk);
@@ -889,6 +916,10 @@ 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 +929,8 @@ 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 +938,7 @@ 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);
--
2.30.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [net 3/4] can: bcm: fix infoleak in struct bcm_msg_head
2021-06-16 11:01 pull-request: can 2021-06-16 Marc Kleine-Budde
2021-06-16 11:01 ` [net 1/4] can: j1939: fix Use-after-Free, hold skb ref while in use Marc Kleine-Budde
2021-06-16 11:01 ` [net 2/4] can: bcm/raw/isotp: use per module netdevice notifier Marc Kleine-Budde
@ 2021-06-16 11:01 ` Marc Kleine-Budde
2021-06-16 11:01 ` [net 4/4] can: mcba_usb: fix memory leak in mcba_usb Marc Kleine-Budde
2021-06-16 19:50 ` pull-request: can 2021-06-16 patchwork-bot+netdevbpf
4 siblings, 0 replies; 6+ messages in thread
From: Marc Kleine-Budde @ 2021-06-16 11:01 UTC (permalink / raw)
To: netdev
Cc: davem, kuba, linux-can, kernel, Norbert Slusarek, linux-stable,
Oliver Hartkopp, Marc Kleine-Budde
From: Norbert Slusarek <nslusarek@gmx.net>
On 64-bit systems, struct bcm_msg_head has an added padding of 4 bytes between
struct members count and ival1. Even though all struct members are initialized,
the 4-byte hole will contain data from the kernel stack. This patch zeroes out
struct bcm_msg_head before usage, preventing infoleaks to userspace.
Fixes: ffd980f976e7 ("[CAN]: Add broadcast manager (bcm) protocol")
Link: https://lore.kernel.org/r/trinity-7c1b2e82-e34f-4885-8060-2cd7a13769ce-1623532166177@3c-app-gmx-bs52
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Norbert Slusarek <nslusarek@gmx.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
net/can/bcm.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/can/bcm.c b/net/can/bcm.c
index f00176b2a6c3..f3e4d9528fa3 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -406,6 +406,7 @@ static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
if (!op->count && (op->flags & TX_COUNTEVT)) {
/* create notification to user */
+ memset(&msg_head, 0, sizeof(msg_head));
msg_head.opcode = TX_EXPIRED;
msg_head.flags = op->flags;
msg_head.count = op->count;
@@ -443,6 +444,7 @@ static void bcm_rx_changed(struct bcm_op *op, struct canfd_frame *data)
/* this element is not throttled anymore */
data->flags &= (BCM_CAN_FLAGS_MASK|RX_RECV);
+ memset(&head, 0, sizeof(head));
head.opcode = RX_CHANGED;
head.flags = op->flags;
head.count = op->count;
@@ -564,6 +566,7 @@ static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
}
/* create notification to user */
+ memset(&msg_head, 0, sizeof(msg_head));
msg_head.opcode = RX_TIMEOUT;
msg_head.flags = op->flags;
msg_head.count = op->count;
--
2.30.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [net 4/4] can: mcba_usb: fix memory leak in mcba_usb
2021-06-16 11:01 pull-request: can 2021-06-16 Marc Kleine-Budde
` (2 preceding siblings ...)
2021-06-16 11:01 ` [net 3/4] can: bcm: fix infoleak in struct bcm_msg_head Marc Kleine-Budde
@ 2021-06-16 11:01 ` Marc Kleine-Budde
2021-06-16 19:50 ` pull-request: can 2021-06-16 patchwork-bot+netdevbpf
4 siblings, 0 replies; 6+ messages in thread
From: Marc Kleine-Budde @ 2021-06-16 11:01 UTC (permalink / raw)
To: netdev
Cc: davem, kuba, linux-can, kernel, Pavel Skripkin, linux-stable,
syzbot+57281c762a3922e14dfe, Marc Kleine-Budde
From: Pavel Skripkin <paskripkin@gmail.com>
Syzbot reported memory leak in SocketCAN driver for Microchip CAN BUS
Analyzer Tool. The problem was in unfreed usb_coherent.
In mcba_usb_start() 20 coherent buffers are allocated and there is
nothing, that frees them:
1) In callback function the urb is resubmitted and that's all
2) In disconnect function urbs are simply killed, but URB_FREE_BUFFER
is not set (see mcba_usb_start) and this flag cannot be used with
coherent buffers.
Fail log:
| [ 1354.053291][ T8413] mcba_usb 1-1:0.0 can0: device disconnected
| [ 1367.059384][ T8420] kmemleak: 20 new suspected memory leaks (see /sys/kernel/debug/kmem)
So, all allocated buffers should be freed with usb_free_coherent()
explicitly
NOTE:
The same pattern for allocating and freeing coherent buffers
is used in drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
Fixes: 51f3baad7de9 ("can: mcba_usb: Add support for Microchip CAN BUS Analyzer")
Link: https://lore.kernel.org/r/20210609215833.30393-1-paskripkin@gmail.com
Cc: linux-stable <stable@vger.kernel.org>
Reported-and-tested-by: syzbot+57281c762a3922e14dfe@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/usb/mcba_usb.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c
index 029e77dfa773..a45865bd7254 100644
--- a/drivers/net/can/usb/mcba_usb.c
+++ b/drivers/net/can/usb/mcba_usb.c
@@ -82,6 +82,8 @@ struct mcba_priv {
bool can_ka_first_pass;
bool can_speed_check;
atomic_t free_ctx_cnt;
+ void *rxbuf[MCBA_MAX_RX_URBS];
+ dma_addr_t rxbuf_dma[MCBA_MAX_RX_URBS];
};
/* CAN frame */
@@ -633,6 +635,7 @@ static int mcba_usb_start(struct mcba_priv *priv)
for (i = 0; i < MCBA_MAX_RX_URBS; i++) {
struct urb *urb = NULL;
u8 *buf;
+ dma_addr_t buf_dma;
/* create a URB, and a buffer for it */
urb = usb_alloc_urb(0, GFP_KERNEL);
@@ -642,7 +645,7 @@ static int mcba_usb_start(struct mcba_priv *priv)
}
buf = usb_alloc_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
- GFP_KERNEL, &urb->transfer_dma);
+ GFP_KERNEL, &buf_dma);
if (!buf) {
netdev_err(netdev, "No memory left for USB buffer\n");
usb_free_urb(urb);
@@ -661,11 +664,14 @@ static int mcba_usb_start(struct mcba_priv *priv)
if (err) {
usb_unanchor_urb(urb);
usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
- buf, urb->transfer_dma);
+ buf, buf_dma);
usb_free_urb(urb);
break;
}
+ priv->rxbuf[i] = buf;
+ priv->rxbuf_dma[i] = buf_dma;
+
/* Drop reference, USB core will take care of freeing it */
usb_free_urb(urb);
}
@@ -708,7 +714,14 @@ static int mcba_usb_open(struct net_device *netdev)
static void mcba_urb_unlink(struct mcba_priv *priv)
{
+ int i;
+
usb_kill_anchored_urbs(&priv->rx_submitted);
+
+ for (i = 0; i < MCBA_MAX_RX_URBS; ++i)
+ usb_free_coherent(priv->udev, MCBA_USB_RX_BUFF_SIZE,
+ priv->rxbuf[i], priv->rxbuf_dma[i]);
+
usb_kill_anchored_urbs(&priv->tx_submitted);
}
--
2.30.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: pull-request: can 2021-06-16
2021-06-16 11:01 pull-request: can 2021-06-16 Marc Kleine-Budde
` (3 preceding siblings ...)
2021-06-16 11:01 ` [net 4/4] can: mcba_usb: fix memory leak in mcba_usb Marc Kleine-Budde
@ 2021-06-16 19:50 ` patchwork-bot+netdevbpf
4 siblings, 0 replies; 6+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-06-16 19:50 UTC (permalink / raw)
To: Marc Kleine-Budde; +Cc: netdev, davem, kuba, linux-can, kernel
Hello:
This pull request was applied to netdev/net.git (refs/heads/master):
On Wed, 16 Jun 2021 13:01:48 +0200 you wrote:
> Hello Jakub, hello David,
>
> this is a pull request of 4 patches for net/master.
>
> The first patch is by Oleksij Rempel and fixes a Use-after-Free found
> by syzbot in the j1939 stack.
>
> [...]
Here is the summary with links:
- pull-request: can 2021-06-16
https://git.kernel.org/netdev/net/c/e82a35aead2f
- [net,2/4] can: bcm/raw/isotp: use per module netdevice notifier
https://git.kernel.org/netdev/net/c/8d0caedb7596
- [net,3/4] can: bcm: fix infoleak in struct bcm_msg_head
https://git.kernel.org/netdev/net/c/5e87ddbe3942
- [net,4/4] can: mcba_usb: fix memory leak in mcba_usb
https://git.kernel.org/netdev/net/c/91c02557174b
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 6+ messages in thread