<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/net/tipc, branch v5.4.71</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>tipc: fix memory leak in service subscripting</title>
<updated>2020-10-01T11:18:00+00:00</updated>
<author>
<name>Tuong Lien</name>
<email>tuong.t.lien@dektech.com.au</email>
</author>
<published>2020-05-13T12:33:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=202ae05859eaac9c84cbbcb3bb73fbb46ddd0829'/>
<id>202ae05859eaac9c84cbbcb3bb73fbb46ddd0829</id>
<content type='text'>
[ Upstream commit 0771d7df819284d46cf5cfb57698621b503ec17f ]

Upon receipt of a service subscription request from user via a topology
connection, one 'sub' object will be allocated in kernel, so it will be
able to send an event of the service if any to the user correspondingly
then. Also, in case of any failure, the connection will be shutdown and
all the pertaining 'sub' objects will be freed.

However, there is a race condition as follows resulting in memory leak:

       receive-work       connection        send-work
              |                |                |
        sub-1 |&lt;------//-------|                |
        sub-2 |&lt;------//-------|                |
              |                |&lt;---------------| evt for sub-x
        sub-3 |&lt;------//-------|                |
              :                :                :
              :                :                :
              |       /--------|                |
              |       |        * peer closed    |
              |       |        |                |
              |       |        |&lt;-------X-------| evt for sub-y
              |       |        |&lt;===============|
        sub-n |&lt;------/        X    shutdown    |
    -&gt; orphan |                                 |

That is, the 'receive-work' may get the last subscription request while
the 'send-work' is shutting down the connection due to peer close.

We had a 'lock' on the connection, so the two actions cannot be carried
out simultaneously. If the last subscription is allocated e.g. 'sub-n',
before the 'send-work' closes the connection, there will be no issue at
all, the 'sub' objects will be freed. In contrast the last subscription
will become orphan since the connection was closed, and we released all
references.

This commit fixes the issue by simply adding one test if the connection
remains in 'connected' state right after we obtain the connection lock,
then a subscription object can be created as usual, otherwise we ignore
it.

Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Reported-by: Thang Ngo &lt;thang.h.ngo@dektech.com.au&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0771d7df819284d46cf5cfb57698621b503ec17f ]

Upon receipt of a service subscription request from user via a topology
connection, one 'sub' object will be allocated in kernel, so it will be
able to send an event of the service if any to the user correspondingly
then. Also, in case of any failure, the connection will be shutdown and
all the pertaining 'sub' objects will be freed.

However, there is a race condition as follows resulting in memory leak:

       receive-work       connection        send-work
              |                |                |
        sub-1 |&lt;------//-------|                |
        sub-2 |&lt;------//-------|                |
              |                |&lt;---------------| evt for sub-x
        sub-3 |&lt;------//-------|                |
              :                :                :
              :                :                :
              |       /--------|                |
              |       |        * peer closed    |
              |       |        |                |
              |       |        |&lt;-------X-------| evt for sub-y
              |       |        |&lt;===============|
        sub-n |&lt;------/        X    shutdown    |
    -&gt; orphan |                                 |

That is, the 'receive-work' may get the last subscription request while
the 'send-work' is shutting down the connection due to peer close.

We had a 'lock' on the connection, so the two actions cannot be carried
out simultaneously. If the last subscription is allocated e.g. 'sub-n',
before the 'send-work' closes the connection, there will be no issue at
all, the 'sub' objects will be freed. In contrast the last subscription
will become orphan since the connection was closed, and we released all
references.

This commit fixes the issue by simply adding one test if the connection
remains in 'connected' state right after we obtain the connection lock,
then a subscription object can be created as usual, otherwise we ignore
it.

Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Reported-by: Thang Ngo &lt;thang.h.ngo@dektech.com.au&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix link overflow issue at socket shutdown</title>
<updated>2020-10-01T11:17:24+00:00</updated>
<author>
<name>Tuong Lien</name>
<email>tuong.t.lien@dektech.com.au</email>
</author>
<published>2020-01-08T02:18:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8c926e159aface3567b2ded6024b1b14c0f27f18'/>
<id>8c926e159aface3567b2ded6024b1b14c0f27f18</id>
<content type='text'>
[ Upstream commit 49afb806cb650dd1f06f191994f3aa657d264009 ]

When a socket is suddenly shutdown or released, it will reject all the
unreceived messages in its receive queue. This applies to a connected
socket too, whereas there is only one 'FIN' message required to be sent
back to its peer in this case.

In case there are many messages in the queue and/or some connections
with such messages are shutdown at the same time, the link layer will
easily get overflowed at the 'TIPC_SYSTEM_IMPORTANCE' backlog level
because of the message rejections. As a result, the link will be taken
down. Moreover, immediately when the link is re-established, the socket
layer can continue to reject the messages and the same issue happens...

The commit refactors the '__tipc_shutdown()' function to only send one
'FIN' in the situation mentioned above. For the connectionless case, it
is unavoidable but usually there is no rejections for such socket
messages because they are 'dest-droppable' by default.

In addition, the new code makes the other socket states clear
(e.g.'TIPC_LISTEN') and treats as a separate case to avoid misbehaving.

Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 49afb806cb650dd1f06f191994f3aa657d264009 ]

When a socket is suddenly shutdown or released, it will reject all the
unreceived messages in its receive queue. This applies to a connected
socket too, whereas there is only one 'FIN' message required to be sent
back to its peer in this case.

In case there are many messages in the queue and/or some connections
with such messages are shutdown at the same time, the link layer will
easily get overflowed at the 'TIPC_SYSTEM_IMPORTANCE' backlog level
because of the message rejections. As a result, the link will be taken
down. Moreover, immediately when the link is re-established, the socket
layer can continue to reject the messages and the same issue happens...

The commit refactors the '__tipc_shutdown()' function to only send one
'FIN' in the situation mentioned above. For the connectionless case, it
is unavoidable but usually there is no rejections for such socket
messages because they are 'dest-droppable' by default.

In addition, the new code makes the other socket states clear
(e.g.'TIPC_LISTEN') and treats as a separate case to avoid misbehaving.

Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Acked-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: use skb_unshare() instead in tipc_buf_append()</title>
<updated>2020-09-26T16:03:14+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2020-09-13T11:37:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=825fc3167cf5c82685fb640d03d1c5028a1cea03'/>
<id>825fc3167cf5c82685fb640d03d1c5028a1cea03</id>
<content type='text'>
[ Upstream commit ff48b6222e65ebdba5a403ef1deba6214e749193 ]

In tipc_buf_append() it may change skb's frag_list, and it causes
problems when this skb is cloned. skb_unclone() doesn't really
make this skb's flag_list available to change.

Shuang Li has reported an use-after-free issue because of this
when creating quite a few macvlan dev over the same dev, where
the broadcast packets will be cloned and go up to the stack:

 [ ] BUG: KASAN: use-after-free in pskb_expand_head+0x86d/0xea0
 [ ] Call Trace:
 [ ]  dump_stack+0x7c/0xb0
 [ ]  print_address_description.constprop.7+0x1a/0x220
 [ ]  kasan_report.cold.10+0x37/0x7c
 [ ]  check_memory_region+0x183/0x1e0
 [ ]  pskb_expand_head+0x86d/0xea0
 [ ]  process_backlog+0x1df/0x660
 [ ]  net_rx_action+0x3b4/0xc90
 [ ]
 [ ] Allocated by task 1786:
 [ ]  kmem_cache_alloc+0xbf/0x220
 [ ]  skb_clone+0x10a/0x300
 [ ]  macvlan_broadcast+0x2f6/0x590 [macvlan]
 [ ]  macvlan_process_broadcast+0x37c/0x516 [macvlan]
 [ ]  process_one_work+0x66a/0x1060
 [ ]  worker_thread+0x87/0xb10
 [ ]
 [ ] Freed by task 3253:
 [ ]  kmem_cache_free+0x82/0x2a0
 [ ]  skb_release_data+0x2c3/0x6e0
 [ ]  kfree_skb+0x78/0x1d0
 [ ]  tipc_recvmsg+0x3be/0xa40 [tipc]

So fix it by using skb_unshare() instead, which would create a new
skb for the cloned frag and it'll be safe to change its frag_list.
The similar things were also done in sctp_make_reassembled_event(),
which is using skb_copy().

Reported-by: Shuang Li &lt;shuali@redhat.com&gt;
Fixes: 37e22164a8a3 ("tipc: rename and move message reassembly function")
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ff48b6222e65ebdba5a403ef1deba6214e749193 ]

In tipc_buf_append() it may change skb's frag_list, and it causes
problems when this skb is cloned. skb_unclone() doesn't really
make this skb's flag_list available to change.

Shuang Li has reported an use-after-free issue because of this
when creating quite a few macvlan dev over the same dev, where
the broadcast packets will be cloned and go up to the stack:

 [ ] BUG: KASAN: use-after-free in pskb_expand_head+0x86d/0xea0
 [ ] Call Trace:
 [ ]  dump_stack+0x7c/0xb0
 [ ]  print_address_description.constprop.7+0x1a/0x220
 [ ]  kasan_report.cold.10+0x37/0x7c
 [ ]  check_memory_region+0x183/0x1e0
 [ ]  pskb_expand_head+0x86d/0xea0
 [ ]  process_backlog+0x1df/0x660
 [ ]  net_rx_action+0x3b4/0xc90
 [ ]
 [ ] Allocated by task 1786:
 [ ]  kmem_cache_alloc+0xbf/0x220
 [ ]  skb_clone+0x10a/0x300
 [ ]  macvlan_broadcast+0x2f6/0x590 [macvlan]
 [ ]  macvlan_process_broadcast+0x37c/0x516 [macvlan]
 [ ]  process_one_work+0x66a/0x1060
 [ ]  worker_thread+0x87/0xb10
 [ ]
 [ ] Freed by task 3253:
 [ ]  kmem_cache_free+0x82/0x2a0
 [ ]  skb_release_data+0x2c3/0x6e0
 [ ]  kfree_skb+0x78/0x1d0
 [ ]  tipc_recvmsg+0x3be/0xa40 [tipc]

So fix it by using skb_unshare() instead, which would create a new
skb for the cloned frag and it'll be safe to change its frag_list.
The similar things were also done in sctp_make_reassembled_event(),
which is using skb_copy().

Reported-by: Shuang Li &lt;shuali@redhat.com&gt;
Fixes: 37e22164a8a3 ("tipc: rename and move message reassembly function")
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix shutdown() of connection oriented socket</title>
<updated>2020-09-26T16:03:14+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@I-love.SAKURA.ne.jp</email>
</author>
<published>2020-09-05T06:14:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5efc178ebd1221fb5d57cc39e5bb0d3feb82eb5d'/>
<id>5efc178ebd1221fb5d57cc39e5bb0d3feb82eb5d</id>
<content type='text'>
[ Upstream commit a4b5cc9e10803ecba64a7d54c0f47e4564b4a980 ]

I confirmed that the problem fixed by commit 2a63866c8b51a3f7 ("tipc: fix
shutdown() of connectionless socket") also applies to stream socket.

----------
#include &lt;sys/socket.h&gt;
#include &lt;unistd.h&gt;
#include &lt;sys/wait.h&gt;

int main(int argc, char *argv[])
{
        int fds[2] = { -1, -1 };
        socketpair(PF_TIPC, SOCK_STREAM /* or SOCK_DGRAM */, 0, fds);
        if (fork() == 0)
                _exit(read(fds[0], NULL, 1));
        shutdown(fds[0], SHUT_RDWR); /* This must make read() return. */
        wait(NULL); /* To be woken up by _exit(). */
        return 0;
}
----------

Since shutdown(SHUT_RDWR) should affect all processes sharing that socket,
unconditionally setting sk-&gt;sk_shutdown to SHUTDOWN_MASK will be the right
behavior.

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a4b5cc9e10803ecba64a7d54c0f47e4564b4a980 ]

I confirmed that the problem fixed by commit 2a63866c8b51a3f7 ("tipc: fix
shutdown() of connectionless socket") also applies to stream socket.

----------
#include &lt;sys/socket.h&gt;
#include &lt;unistd.h&gt;
#include &lt;sys/wait.h&gt;

int main(int argc, char *argv[])
{
        int fds[2] = { -1, -1 };
        socketpair(PF_TIPC, SOCK_STREAM /* or SOCK_DGRAM */, 0, fds);
        if (fork() == 0)
                _exit(read(fds[0], NULL, 1));
        shutdown(fds[0], SHUT_RDWR); /* This must make read() return. */
        wait(NULL); /* To be woken up by _exit(). */
        return 0;
}
----------

Since shutdown(SHUT_RDWR) should affect all processes sharing that socket,
unconditionally setting sk-&gt;sk_shutdown to SHUTDOWN_MASK will be the right
behavior.

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: Fix memory leak in tipc_group_create_member()</title>
<updated>2020-09-26T16:03:13+00:00</updated>
<author>
<name>Peilin Ye</name>
<email>yepeilin.cs@gmail.com</email>
</author>
<published>2020-09-13T08:06:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=586b14ec481c9d6dd9db8994f991dd8725e8b093'/>
<id>586b14ec481c9d6dd9db8994f991dd8725e8b093</id>
<content type='text'>
[ Upstream commit bb3a420d47ab00d7e1e5083286cab15235a96680 ]

tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an
existing node, causing tipc_group_create_member() to leak memory. Let
tipc_group_add_to_tree() return an error in such a case, so that
tipc_group_create_member() can handle it properly.

Fixes: 75da2163dbb6 ("tipc: introduce communication groups")
Reported-and-tested-by: syzbot+f95d90c454864b3b5bc9@syzkaller.appspotmail.com
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13aff
Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit bb3a420d47ab00d7e1e5083286cab15235a96680 ]

tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an
existing node, causing tipc_group_create_member() to leak memory. Let
tipc_group_add_to_tree() return an error in such a case, so that
tipc_group_create_member() can handle it properly.

Fixes: 75da2163dbb6 ("tipc: introduce communication groups")
Reported-and-tested-by: syzbot+f95d90c454864b3b5bc9@syzkaller.appspotmail.com
Cc: Hillf Danton &lt;hdanton@sina.com&gt;
Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13aff
Signed-off-by: Peilin Ye &lt;yepeilin.cs@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix shutdown() of connectionless socket</title>
<updated>2020-09-12T12:18:55+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@I-love.SAKURA.ne.jp</email>
</author>
<published>2020-09-02T13:44:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=09c45065257b5b194e08a1b4749daeebb961675e'/>
<id>09c45065257b5b194e08a1b4749daeebb961675e</id>
<content type='text'>
[ Upstream commit 2a63866c8b51a3f72cea388dfac259d0e14c4ba6 ]

syzbot is reporting hung task at nbd_ioctl() [1], for there are two
problems regarding TIPC's connectionless socket's shutdown() operation.

----------
#include &lt;fcntl.h&gt;
#include &lt;sys/socket.h&gt;
#include &lt;sys/ioctl.h&gt;
#include &lt;linux/nbd.h&gt;
#include &lt;unistd.h&gt;

int main(int argc, char *argv[])
{
        const int fd = open("/dev/nbd0", 3);
        alarm(5);
        ioctl(fd, NBD_SET_SOCK, socket(PF_TIPC, SOCK_DGRAM, 0));
        ioctl(fd, NBD_DO_IT, 0); /* To be interrupted by SIGALRM. */
        return 0;
}
----------

One problem is that wait_for_completion() from flush_workqueue() from
nbd_start_device_ioctl() from nbd_ioctl() cannot be completed when
nbd_start_device_ioctl() received a signal at wait_event_interruptible(),
for tipc_shutdown() from kernel_sock_shutdown(SHUT_RDWR) from
nbd_mark_nsock_dead() from sock_shutdown() from nbd_start_device_ioctl()
is failing to wake up a WQ thread sleeping at wait_woken() from
tipc_wait_for_rcvmsg() from sock_recvmsg() from sock_xmit() from
nbd_read_stat() from recv_work() scheduled by nbd_start_device() from
nbd_start_device_ioctl(). Fix this problem by always invoking
sk-&gt;sk_state_change() (like inet_shutdown() does) when tipc_shutdown() is
called.

The other problem is that tipc_wait_for_rcvmsg() cannot return when
tipc_shutdown() is called, for tipc_shutdown() sets sk-&gt;sk_shutdown to
SEND_SHUTDOWN (despite "how" is SHUT_RDWR) while tipc_wait_for_rcvmsg()
needs sk-&gt;sk_shutdown set to RCV_SHUTDOWN or SHUTDOWN_MASK. Fix this
problem by setting sk-&gt;sk_shutdown to SHUTDOWN_MASK (like inet_shutdown()
does) when the socket is connectionless.

[1] https://syzkaller.appspot.com/bug?id=3fe51d307c1f0a845485cf1798aa059d12bf18b2

Reported-by: syzbot &lt;syzbot+e36f41d207137b5d12f7@syzkaller.appspotmail.com&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 2a63866c8b51a3f72cea388dfac259d0e14c4ba6 ]

syzbot is reporting hung task at nbd_ioctl() [1], for there are two
problems regarding TIPC's connectionless socket's shutdown() operation.

----------
#include &lt;fcntl.h&gt;
#include &lt;sys/socket.h&gt;
#include &lt;sys/ioctl.h&gt;
#include &lt;linux/nbd.h&gt;
#include &lt;unistd.h&gt;

int main(int argc, char *argv[])
{
        const int fd = open("/dev/nbd0", 3);
        alarm(5);
        ioctl(fd, NBD_SET_SOCK, socket(PF_TIPC, SOCK_DGRAM, 0));
        ioctl(fd, NBD_DO_IT, 0); /* To be interrupted by SIGALRM. */
        return 0;
}
----------

One problem is that wait_for_completion() from flush_workqueue() from
nbd_start_device_ioctl() from nbd_ioctl() cannot be completed when
nbd_start_device_ioctl() received a signal at wait_event_interruptible(),
for tipc_shutdown() from kernel_sock_shutdown(SHUT_RDWR) from
nbd_mark_nsock_dead() from sock_shutdown() from nbd_start_device_ioctl()
is failing to wake up a WQ thread sleeping at wait_woken() from
tipc_wait_for_rcvmsg() from sock_recvmsg() from sock_xmit() from
nbd_read_stat() from recv_work() scheduled by nbd_start_device() from
nbd_start_device_ioctl(). Fix this problem by always invoking
sk-&gt;sk_state_change() (like inet_shutdown() does) when tipc_shutdown() is
called.

The other problem is that tipc_wait_for_rcvmsg() cannot return when
tipc_shutdown() is called, for tipc_shutdown() sets sk-&gt;sk_shutdown to
SEND_SHUTDOWN (despite "how" is SHUT_RDWR) while tipc_wait_for_rcvmsg()
needs sk-&gt;sk_shutdown set to RCV_SHUTDOWN or SHUTDOWN_MASK. Fix this
problem by setting sk-&gt;sk_shutdown to SHUTDOWN_MASK (like inet_shutdown()
does) when the socket is connectionless.

[1] https://syzkaller.appspot.com/bug?id=3fe51d307c1f0a845485cf1798aa059d12bf18b2

Reported-by: syzbot &lt;syzbot+e36f41d207137b5d12f7@syzkaller.appspotmail.com&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix uninit skb-&gt;data in tipc_nl_compat_dumpit()</title>
<updated>2020-09-03T09:26:40+00:00</updated>
<author>
<name>Cong Wang</name>
<email>xiyou.wangcong@gmail.com</email>
</author>
<published>2020-08-15T23:29:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6c2e795f95cddd4a4e4f74a6aa7412a3ccf9fc01'/>
<id>6c2e795f95cddd4a4e4f74a6aa7412a3ccf9fc01</id>
<content type='text'>
[ Upstream commit 47733f9daf4fe4f7e0eb9e273f21ad3a19130487 ]

__tipc_nl_compat_dumpit() has two callers, and it expects them to
pass a valid nlmsghdr via arg-&gt;data. This header is artificial and
crafted just for __tipc_nl_compat_dumpit().

tipc_nl_compat_publ_dump() does so by putting a genlmsghdr as well
as some nested attribute, TIPC_NLA_SOCK. But the other caller
tipc_nl_compat_dumpit() does not, this leaves arg-&gt;data uninitialized
on this call path.

Fix this by just adding a similar nlmsghdr without any payload in
tipc_nl_compat_dumpit().

This bug exists since day 1, but the recent commit 6ea67769ff33
("net: tipc: prepare attrs in __tipc_nl_compat_dumpit()") makes it
easier to appear.

Reported-and-tested-by: syzbot+0e7181deafa7e0b79923@syzkaller.appspotmail.com
Fixes: d0796d1ef63d ("tipc: convert legacy nl bearer dump to nl compat")
Cc: Jon Maloy &lt;jmaloy@redhat.com&gt;
Cc: Ying Xue &lt;ying.xue@windriver.com&gt;
Cc: Richard Alpe &lt;richard.alpe@ericsson.com&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 47733f9daf4fe4f7e0eb9e273f21ad3a19130487 ]

__tipc_nl_compat_dumpit() has two callers, and it expects them to
pass a valid nlmsghdr via arg-&gt;data. This header is artificial and
crafted just for __tipc_nl_compat_dumpit().

tipc_nl_compat_publ_dump() does so by putting a genlmsghdr as well
as some nested attribute, TIPC_NLA_SOCK. But the other caller
tipc_nl_compat_dumpit() does not, this leaves arg-&gt;data uninitialized
on this call path.

Fix this by just adding a similar nlmsghdr without any payload in
tipc_nl_compat_dumpit().

This bug exists since day 1, but the recent commit 6ea67769ff33
("net: tipc: prepare attrs in __tipc_nl_compat_dumpit()") makes it
easier to appear.

Reported-and-tested-by: syzbot+0e7181deafa7e0b79923@syzkaller.appspotmail.com
Fixes: d0796d1ef63d ("tipc: convert legacy nl bearer dump to nl compat")
Cc: Jon Maloy &lt;jmaloy@redhat.com&gt;
Cc: Ying Xue &lt;ying.xue@windriver.com&gt;
Cc: Richard Alpe &lt;richard.alpe@ericsson.com&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: block BH before using dst_cache</title>
<updated>2020-06-03T06:21:03+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2020-05-21T18:29:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8c9df6ced1f95970254d2e912dc7c678c2d9de02'/>
<id>8c9df6ced1f95970254d2e912dc7c678c2d9de02</id>
<content type='text'>
[ Upstream commit 1378817486d6860f6a927f573491afe65287abf1 ]

dst_cache_get() documents it must be used with BH disabled.

sysbot reported :

BUG: using smp_processor_id() in preemptible [00000000] code: /21697
caller is dst_cache_get+0x3a/0xb0 net/core/dst_cache.c:68
CPU: 0 PID: 21697 Comm:  Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 check_preemption_disabled lib/smp_processor_id.c:47 [inline]
 debug_smp_processor_id.cold+0x88/0x9b lib/smp_processor_id.c:57
 dst_cache_get+0x3a/0xb0 net/core/dst_cache.c:68
 tipc_udp_xmit.isra.0+0xb9/0xad0 net/tipc/udp_media.c:164
 tipc_udp_send_msg+0x3e6/0x490 net/tipc/udp_media.c:244
 tipc_bearer_xmit_skb+0x1de/0x3f0 net/tipc/bearer.c:526
 tipc_enable_bearer+0xb2f/0xd60 net/tipc/bearer.c:331
 __tipc_nl_bearer_enable+0x2bf/0x390 net/tipc/bearer.c:995
 tipc_nl_bearer_enable+0x1e/0x30 net/tipc/bearer.c:1003
 genl_family_rcv_msg_doit net/netlink/genetlink.c:673 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:718 [inline]
 genl_rcv_msg+0x627/0xdf0 net/netlink/genetlink.c:735
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:746
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
 ___sys_sendmsg+0x100/0x170 net/socket.c:2416
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29

Fixes: e9c1a793210f ("tipc: add dst_cache support for udp media")
Cc: Xin Long &lt;lucien.xin@gmail.com&gt;
Cc: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1378817486d6860f6a927f573491afe65287abf1 ]

dst_cache_get() documents it must be used with BH disabled.

sysbot reported :

BUG: using smp_processor_id() in preemptible [00000000] code: /21697
caller is dst_cache_get+0x3a/0xb0 net/core/dst_cache.c:68
CPU: 0 PID: 21697 Comm:  Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 check_preemption_disabled lib/smp_processor_id.c:47 [inline]
 debug_smp_processor_id.cold+0x88/0x9b lib/smp_processor_id.c:57
 dst_cache_get+0x3a/0xb0 net/core/dst_cache.c:68
 tipc_udp_xmit.isra.0+0xb9/0xad0 net/tipc/udp_media.c:164
 tipc_udp_send_msg+0x3e6/0x490 net/tipc/udp_media.c:244
 tipc_bearer_xmit_skb+0x1de/0x3f0 net/tipc/bearer.c:526
 tipc_enable_bearer+0xb2f/0xd60 net/tipc/bearer.c:331
 __tipc_nl_bearer_enable+0x2bf/0x390 net/tipc/bearer.c:995
 tipc_nl_bearer_enable+0x1e/0x30 net/tipc/bearer.c:1003
 genl_family_rcv_msg_doit net/netlink/genetlink.c:673 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:718 [inline]
 genl_rcv_msg+0x627/0xdf0 net/netlink/genetlink.c:735
 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:746
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
 ___sys_sendmsg+0x100/0x170 net/socket.c:2416
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca29

Fixes: e9c1a793210f ("tipc: add dst_cache support for udp media")
Cc: Xin Long &lt;lucien.xin@gmail.com&gt;
Cc: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: fix partial topology connection closure</title>
<updated>2020-05-14T05:58:22+00:00</updated>
<author>
<name>Tuong Lien</name>
<email>tuong.t.lien@dektech.com.au</email>
</author>
<published>2020-05-04T04:15:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e9edd5a0f5f5e586d5f451b54d060efb51196be7'/>
<id>e9edd5a0f5f5e586d5f451b54d060efb51196be7</id>
<content type='text'>
[ Upstream commit 980d69276f3048af43a045be2925dacfb898a7be ]

When an application connects to the TIPC topology server and subscribes
to some services, a new connection is created along with some objects -
'tipc_subscription' to store related data correspondingly...
However, there is one omission in the connection handling that when the
connection or application is orderly shutdown (e.g. via SIGQUIT, etc.),
the connection is not closed in kernel, the 'tipc_subscription' objects
are not freed too.
This results in:
- The maximum number of subscriptions (65535) will be reached soon, new
subscriptions will be rejected;
- TIPC module cannot be removed (unless the objects  are somehow forced
to release first);

The commit fixes the issue by closing the connection if the 'recvmsg()'
returns '0' i.e. when the peer is shutdown gracefully. It also includes
the other unexpected cases.

Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 980d69276f3048af43a045be2925dacfb898a7be ]

When an application connects to the TIPC topology server and subscribes
to some services, a new connection is created along with some objects -
'tipc_subscription' to store related data correspondingly...
However, there is one omission in the connection handling that when the
connection or application is orderly shutdown (e.g. via SIGQUIT, etc.),
the connection is not closed in kernel, the 'tipc_subscription' objects
are not freed too.
This results in:
- The maximum number of subscriptions (65535) will be reached soon, new
subscriptions will be rejected;
- TIPC module cannot be removed (unless the objects  are somehow forced
to release first);

The commit fixes the issue by closing the connection if the 'recvmsg()'
returns '0' i.e. when the peer is shutdown gracefully. It also includes
the other unexpected cases.

Acked-by: Jon Maloy &lt;jmaloy@redhat.com&gt;
Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: Tuong Lien &lt;tuong.t.lien@dektech.com.au&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tipc: add missing attribute validation for MTU property</title>
<updated>2020-03-18T06:17:45+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2020-03-03T05:05:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4c16ef8ee16ced7585b1ec3fc8df35cd4c3b385c'/>
<id>4c16ef8ee16ced7585b1ec3fc8df35cd4c3b385c</id>
<content type='text'>
[ Upstream commit 213320a67962ff6e7b83b704d55cbebc341426db ]

Add missing attribute validation for TIPC_NLA_PROP_MTU
to the netlink policy.

Fixes: 901271e0403a ("tipc: implement configuration of UDP media MTU")
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 213320a67962ff6e7b83b704d55cbebc341426db ]

Add missing attribute validation for TIPC_NLA_PROP_MTU
to the netlink policy.

Fixes: 901271e0403a ("tipc: implement configuration of UDP media MTU")
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
