Commit Graph

224 Commits

Author SHA1 Message Date
Hyunwoo Kim f2b0b5210f net/x25: Fix to not accept on connected socket
When listen() and accept() are called on an x25 socket
that connect() succeeds, accept() succeeds immediately.
This is because x25_connect() queues the skb to
sk->sk_receive_queue, and x25_accept() dequeues it.

This creates a child socket with the sk of the parent
x25 socket, which can cause confusion.

Fix x25_listen() to return -EINVAL if the socket has
already been successfully connect()ed to avoid this issue.

Signed-off-by: Hyunwoo Kim <v4bel@theori.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-25 09:51:04 +00:00
Wei Yongjun 2929cceb2f net/x25: Fix skb leak in x25_lapb_receive_frame()
x25_lapb_receive_frame() using skb_copy() to get a private copy of
skb, the new skb should be freed in the undersized/fragmented skb
error handling path. Otherwise there is a memory leak.

Fixes: cb101ed2c3 ("x25: Handle undersized/fragmented skbs")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Martin Schiller <ms@dev.tdt.de>
Link: https://lore.kernel.org/r/20221114110519.514538-1-weiyongjun@huaweicloud.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-15 20:22:19 -08:00
Martin Schiller 944e594cfa net/x25: fix call timeouts in blocking connects
When a userspace application starts a blocking connect(), a CALL REQUEST
is sent, the t21 timer is started and the connect is waiting in
x25_wait_for_connection_establishment(). If then for some reason the t21
timer expires before any reaction on the assigned logical channel (e.g.
CALL ACCEPT, CLEAR REQUEST), there is sent a CLEAR REQUEST and timer
t23 is started waiting for a CLEAR confirmation. If we now receive a
CLEAR CONFIRMATION from the peer, x25_disconnect() is called in
x25_state2_machine() with reason "0", which means "normal" call
clearing. This is ok, but the parameter "reason" is used as sk->sk_err
in x25_disconnect() and sock_error(sk) is evaluated in
x25_wait_for_connection_establishment() to check if the call is still
pending. As "0" is not rated as an error, the connect will stuck here
forever.

To fix this situation, also check if the sk->sk_state changed form
TCP_SYN_SENT to TCP_CLOSE in the meantime, which is also done by
x25_disconnect().

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Link: https://lore.kernel.org/r/20220805061810.10824-1-ms@dev.tdt.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-08 20:48:51 -07:00
Colin Ian King ecd17a87eb x25: remove redundant pointer dev
Pointer dev is being assigned a value that is never used, the assignment
and the variable are redundant and can be removed. Also replace null check
with the preferred !ptr idiom.

Cleans up clang scan warning:
net/x25/x25_proc.c:94:26: warning: Although the value stored to 'dev' is
used in the enclosing expression, the value is never actually read
from 'dev' [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220508214500.60446-1-colin.i.king@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-05-10 11:59:22 +02:00
Oliver Hartkopp f4b41f062c net: remove noblock parameter from skb_recv_datagram()
skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-06 13:45:26 +01:00
Duoming Zhou 7781607938 net/x25: Fix null-ptr-deref caused by x25_disconnect
When the link layer is terminating, x25->neighbour will be set to NULL
in x25_disconnect(). As a result, it could cause null-ptr-deref bugs in
x25_sendmsg(),x25_recvmsg() and x25_connect(). One of the bugs is
shown below.

    (Thread 1)                 |  (Thread 2)
x25_link_terminated()          | x25_recvmsg()
 x25_kill_by_neigh()           |  ...
  x25_disconnect()             |  lock_sock(sk)
   ...                         |  ...
   x25->neighbour = NULL //(1) |
   ...                         |  x25->neighbour->extended //(2)

The code sets NULL to x25->neighbour in position (1) and dereferences
x25->neighbour in position (2), which could cause null-ptr-deref bug.

This patch adds lock_sock() in x25_kill_by_neigh() in order to synchronize
with x25_sendmsg(), x25_recvmsg() and x25_connect(). What`s more, the
sock held by lock_sock() is not NULL, because it is extracted from x25_list
and uses x25_list_lock to synchronize.

Fixes: 4becb7ee5b ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-26 11:48:16 -07:00
Jean Sacren 9745177c94 net: x25: drop harmless check of !more
'more' is checked first.  When !more is checked immediately after that,
it is always true.  We should drop this check.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Acked-by: Martin Schiller <ms@dev.tdt.de>
Link: https://lore.kernel.org/r/20211208024732.142541-5-sakiwit@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09 18:35:11 -08:00
Wang Hai bc831facf8 net: x25: Use list_for_each_entry() to simplify code in x25_route.c
Convert list_for_each() to list_for_each_entry() where
applicable. This simplifies the code.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-10 14:08:09 -07:00
gushengxian db67f24934 net/x25: fix a mistake in grammar
Fix a mistake in grammar.

Signed-off-by: gushengxian <gushengxian@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-09 13:54:26 -07:00
Wang Hai 96bffe7023 net: x25: Use list_for_each_entry() to simplify code in x25_forward.c
Convert list_for_each() to list_for_each_entry() where
applicable. This simplifies the code.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 16:31:25 -07:00
Wang Hai 3835a6614a net: x25: Use list_for_each_entry() to simplify code in x25_link.c
Convert list_for_each() to list_for_each_entry() where
applicable. This simplifies the code.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 16:31:24 -07:00
Zheng Yongjun d773695866 net/x25: Return the correct errno code
When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 15:13:56 -07:00
Bhaskar Chowdhury 8406d38fde af_x25.c: Fix a spello
s/facilties/facilities/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-28 17:31:13 -07:00
Xie He 13458ffe0a net: x25: Remove unimplemented X.25-over-LLC code stubs
According to the X.25 documentation, there was a plan to implement
X.25-over-802.2-LLC. It never finished but left various code stubs in the
X.25 code. At this time it is unlikely that it would ever finish so it
may be better to remove those code stubs.

Also change the documentation to make it clear that this is not a ongoing
plan anymore. Change words like "will" to "could", "would", etc.

Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Link: https://lore.kernel.org/r/20201209033346.83742-1-xie.he.0141@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-12 17:15:33 -08:00
Xie He 6b21c0bb3a net: x25: Fix handling of Restart Request and Restart Confirmation
1. When the x25 module gets loaded, layer 2 may already be running and
connected. In this case, although we are in X25_LINK_STATE_0, we still
need to handle the Restart Request received, rather than ignore it.

2. When we are in X25_LINK_STATE_2, we have already sent a Restart Request
and is waiting for the Restart Confirmation with t20timer. t20timer will
restart itself repeatedly forever so it will always be there, as long as we
are in State 2. So we don't need to check x25_t20timer_pending again.

Fixes: d023b2b9cc ("net/x25: fix restart request/confirm handling")
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Acked-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-09 19:34:25 -08:00
Jakub Kicinski 55fd59b003 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:
	drivers/net/ethernet/ibm/ibmvnic.c

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-03 15:44:09 -08:00
Dan Carpenter 6ee50c8e26 net/x25: prevent a couple of overflows
The .x25_addr[] address comes from the user and is not necessarily
NUL terminated.  This leads to a couple problems.  The first problem is
that the strlen() in x25_bind() can read beyond the end of the buffer.

The second problem is more subtle and could result in memory corruption.
The call tree is:
  x25_connect()
  --> x25_write_internal()
      --> x25_addr_aton()

The .x25_addr[] buffers are copied to the "addresses" buffer from
x25_write_internal() so it will lead to stack corruption.

Verify that the strings are NUL terminated and return -EINVAL if they
are not.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Fixes: a9288525d2 ("X25: Dont let x25_bind use addresses containing characters")
Reported-by: "kiyin(尹亮)" <kiyin@tencent.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Martin Schiller <ms@dev.tdt.de>
Link: https://lore.kernel.org/r/X8ZeAKm8FnFpN//B@mwanda
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-02 17:26:36 -08:00
Martin Schiller 139d6eb149 net/x25: remove x25_kill_by_device()
Remove obsolete function x25_kill_by_device(). It's not used any more.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 17:22:51 -08:00
Martin Schiller d023b2b9cc net/x25: fix restart request/confirm handling
We have to take the actual link state into account to handle
restart requests/confirms well.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 17:22:51 -08:00
Martin Schiller 7eed751b3b net/x25: handle additional netdev events
1. Add / remove x25_link_device by NETDEV_REGISTER/UNREGISTER and also
   by NETDEV_POST_TYPE_CHANGE/NETDEV_PRE_TYPE_CHANGE.

   This change is needed so that the x25_neigh struct for an interface
   is already created when it shows up and is kept independently if the
   interface goes UP or DOWN.

   This is used in an upcomming commit, where x25 params of an neighbour
   will get configurable through ioctls.

2. NETDEV_CHANGE event makes it possible to handle carrier loss and
   detection. If carrier is lost, clean up everything related to this
   neighbour by calling x25_link_terminated().

3. Also call x25_link_terminated() for NETDEV_DOWN events and remove the
   call to x25_clear_forward_by_dev() in x25_route_device_down(), as
   this is already called by x25_kill_by_neigh() which gets called by
   x25_link_terminated().

4. Do nothing for NETDEV_UP and NETDEV_GOING_DOWN events, as these will
   be handled in layer 2 (LAPB) and layer3 (X.25) will be informed by
   layer2 when layer2 link is established and layer3 link should be
   initiated.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 17:22:51 -08:00
Xie He 4ee18c179e net: x25: Increase refcnt of "struct x25_neigh" in x25_rx_call_request
The x25_disconnect function in x25_subr.c would decrease the refcount of
"x25->neighbour" (struct x25_neigh) and reset this pointer to NULL.

However, the x25_rx_call_request function in af_x25.c, which is called
when we receive a connection request, does not increase the refcount when
it assigns the pointer.

Fix this issue by increasing the refcount of "struct x25_neigh" in
x25_rx_call_request.

This patch fixes frequent kernel crashes when using AF_X25 sockets.

Fixes: 4becb7ee5b ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Link: https://lore.kernel.org/r/20201112103506.5875-1-xie.he.0141@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-12 18:01:40 -08:00
Martin Schiller 3611823087 net/x25: Fix null-ptr-deref in x25_connect
This fixes a regression for blocking connects introduced by commit
4becb7ee5b ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect").

The x25->neighbour is already set to "NULL" by x25_disconnect() now,
while a blocking connect is waiting in
x25_wait_for_connection_establishment(). Therefore x25->neighbour must
not be accessed here again and x25->state is also already set to
X25_STATE_0 by x25_disconnect().

Fixes: 4becb7ee5b ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Reviewed-by: Xie He <xie.he.0141@gmail.com>
Link: https://lore.kernel.org/r/20201109065449.9014-1-ms@dev.tdt.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-11 14:53:56 -08:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Christoph Hellwig a7b75c5a8c net: pass a sockptr_t into ->setsockopt
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer.  This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24 15:41:54 -07:00
Andrew Lunn 62c89238b1 net: x25: kerneldoc fixes
Simple fixes which require no deep knowledge of the code.

Cc: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-13 17:20:40 -07:00
Alexander A. Klimov 535094a0c9 Replace HTTP links with HTTPS ones: X.25 network layer
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
          If both the HTTP and HTTPS versions
          return 200 OK and serve the same content:
            Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-07 15:44:44 -07:00
Masahiro Yamada a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
David S. Miller 3793faad7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts were all overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 22:10:13 -07:00
Mauro Carvalho Chehab c4ea03fdfd docs: networking: convert x25.txt to ReST
Not much to be done here:
- add SPDX header;
- add a document title;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-01 12:24:40 -07:00
Mauro Carvalho Chehab 883780af72 docs: networking: convert x25-iface.txt to ReST
Not much to be done here:

- add SPDX header;
- adjust title markup;
- remove a tail whitespace;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-01 12:24:40 -07:00
YueHaibing 8999dc8949 net/x25: Fix null-ptr-deref in x25_disconnect
We should check null before do x25_neigh_put in x25_disconnect,
otherwise may cause null-ptr-deref like this:

 #include <sys/socket.h>
 #include <linux/x25.h>

 int main() {
    int sck_x25;
    sck_x25 = socket(AF_X25, SOCK_SEQPACKET, 0);
    close(sck_x25);
    return 0;
 }

BUG: kernel NULL pointer dereference, address: 00000000000000d8
CPU: 0 PID: 4817 Comm: t2 Not tainted 5.7.0-rc3+ #159
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-
RIP: 0010:x25_disconnect+0x91/0xe0
Call Trace:
 x25_release+0x18a/0x1b0
 __sock_release+0x3d/0xc0
 sock_close+0x13/0x20
 __fput+0x107/0x270
 ____fput+0x9/0x10
 task_work_run+0x6d/0xb0
 exit_to_usermode_loop+0x102/0x110
 do_syscall_64+0x23c/0x260
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Reported-by: syzbot+6db548b615e5aeefdce2@syzkaller.appspotmail.com
Fixes: 4becb7ee5b ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28 14:08:59 -07:00
Xiyu Yang 4becb7ee5b net/x25: Fix x25_neigh refcnt leak when x25 disconnect
x25_connect() invokes x25_get_neigh(), which returns a reference of the
specified x25_neigh object to "x25->neighbour" with increased refcnt.

When x25 connect success and returns, the reference still be hold by
"x25->neighbour", so the refcount should be decreased in
x25_disconnect() to keep refcount balanced.

The reference counting issue happens in x25_disconnect(), which forgets
to decrease the refcnt increased by x25_get_neigh() in x25_connect(),
causing a refcnt leak.

Fix this issue by calling x25_neigh_put() before x25_disconnect()
returns.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-27 11:20:30 -07:00
Xiyu Yang f35d12971b net/x25: Fix x25_neigh refcnt leak when receiving frame
x25_lapb_receive_frame() invokes x25_get_neigh(), which returns a
reference of the specified x25_neigh object to "nb" with increased
refcnt.

When x25_lapb_receive_frame() returns, local variable "nb" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one path of
x25_lapb_receive_frame(). When pskb_may_pull() returns false, the
function forgets to decrease the refcnt increased by x25_get_neigh(),
causing a refcnt leak.

Fix this issue by calling x25_neigh_put() when pskb_may_pull() returns
false.

Fixes: cb101ed2c3 ("x25: Handle undersized/fragmented skbs")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23 15:39:39 -07:00
chenqiwu 1e5946f5f7 net: x25: convert to list_for_each_entry_safe()
Use list_for_each_entry_safe() instead of list_for_each_safe()
to simplify the code.

Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-16 18:59:42 -08:00
Martin Schiller e21dba7a4d net/x25: fix nonblocking connect
This patch fixes 2 issues in x25_connect():

1. It makes absolutely no sense to reset the neighbour and the
connection state after a (successful) nonblocking call of x25_connect.
This prevents any connection from being established, since the response
(call accept) cannot be processed.

2. Any further calls to x25_connect() while a call is pending should
simply return, instead of creating new Call Request (on different
logical channels).

This patch should also fix the "KASAN: null-ptr-deref Write in
x25_connect" and "BUG: unable to handle kernel NULL pointer dereference
in x25_connect" bugs reported by syzbot.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Reported-by: syzbot+429c200ffc8772bfe070@syzkaller.appspotmail.com
Reported-by: syzbot+eec0c87f31a7c3b66f7b@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-09 18:39:33 -08:00
Martin Schiller f8fc57e8d7 net/x25: add new state X25_STATE_5
This is needed, because if the flag X25_ACCPT_APPRV_FLAG is not set on a
socket (manual call confirmation) and the channel is cleared by remote
before the manual call confirmation was sent, this situation needs to
be handled.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-09 10:28:43 -08:00
Eric Dumazet 7976a11b30 net: use helpers to change sk_ack_backlog
Writers are holding a lock, but many readers do not.

Following patch will add appropriate barriers in
sk_acceptq_removed() and sk_acceptq_added().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06 16:14:48 -08:00
Eric Dumazet 8265792bf8 net: silence KCSAN warnings around sk_add_backlog() calls
sk_add_backlog() callers usually read sk->sk_rcvbuf without
owning the socket lock. This means sk_rcvbuf value can
be changed by other cpus, and KCSAN complains.

Add READ_ONCE() annotations to document the lockless nature
of these reads.

Note that writes over sk_rcvbuf should also use WRITE_ONCE(),
but this will be done in separate patches to ease stable
backports (if we decide this is relevant for stable trees).

BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg

write to 0xffff88812ab369f8 of 8 bytes by interrupt on cpu 1:
 __sk_add_backlog include/net/sock.h:902 [inline]
 sk_add_backlog include/net/sock.h:933 [inline]
 tcp_add_backlog+0x45a/0xcc0 net/ipv4/tcp_ipv4.c:1737
 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925
 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418

read to 0xffff88812ab369f8 of 8 bytes by task 7271 on cpu 0:
 tcp_recvmsg+0x470/0x1a30 net/ipv4/tcp.c:2047
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_recvmsg+0x92/0xb0 net/socket.c:885
 sock_read_iter+0x15f/0x1e0 net/socket.c:967
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446
 ksys_read+0xd5/0x1b0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x4c/0x60 fs/read_write.c:595
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7271 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-09 21:42:59 -07:00
Thomas Gleixner ee5d8f4d89 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 41
Based on 1 normalized pattern(s):

  this module is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 18 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.008906948@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:12 +02:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Arnd Bergmann c7cbdbf29f net: rework SIOCGSTAMP ioctl handling
The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.

Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-19 14:07:40 -07:00
Eric Dumazet ee74d0bd43 net/x25: reset state in x25_connect()
In case x25_connect() fails and frees the socket neighbour,
we also need to undo the change done to x25->state.

Before my last bug fix, we had use-after-free so this
patch fixes a latent bug.

syzbot report :

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 16137 Comm: syz-executor.1 Not tainted 5.0.0+ #117
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:x25_write_internal+0x1e8/0xdf0 net/x25/x25_subr.c:173
Code: 00 40 88 b5 e0 fe ff ff 0f 85 01 0b 00 00 48 8b 8b 80 04 00 00 48 ba 00 00 00 00 00 fc ff df 48 8d 79 1c 48 89 fe 48 c1 ee 03 <0f> b6 34 16 48 89 fa 83 e2 07 83 c2 03 40 38 f2 7c 09 40 84 f6 0f
RSP: 0018:ffff888076717a08 EFLAGS: 00010207
RAX: ffff88805f2f2292 RBX: ffff8880a0ae6000 RCX: 0000000000000000
kobject: 'loop5' (0000000018d0d0ee): kobject_uevent_env
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: 000000000000001c
RBP: ffff888076717b40 R08: ffff8880950e0580 R09: ffffed100be5e46d
R10: ffffed100be5e46c R11: ffff88805f2f2363 R12: ffff888065579840
kobject: 'loop5' (0000000018d0d0ee): fill_kobj_path: path = '/devices/virtual/block/loop5'
R13: 1ffff1100ece2f47 R14: 0000000000000013 R15: 0000000000000013
FS:  00007fb88cf43700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9a42a41028 CR3: 0000000087a67000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 x25_release+0xd0/0x340 net/x25/af_x25.c:658
 __sock_release+0xd3/0x2b0 net/socket.c:579
 sock_close+0x1b/0x30 net/socket.c:1162
 __fput+0x2df/0x8d0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 get_signal+0x1961/0x1d50 kernel/signal.c:2388
 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457f29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb88cf42c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 0000000000457f29
RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb88cf436d4
R13: 00000000004be462 R14: 00000000004cec98 R15: 00000000ffffffff
Modules linked in:

Fixes: 95d6ebd53c ("net/x25: fix use-after-free in x25_device_event()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: andrew hendry <andrew.hendry@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-11 15:40:14 -07:00
Eric Dumazet 95d6ebd53c net/x25: fix use-after-free in x25_device_event()
In case of failure x25_connect() does a x25_neigh_put(x25->neighbour)
but forgets to clear x25->neighbour pointer, thus triggering use-after-free.

Since the socket is visible in x25_list, we need to hold x25_list_lock
to protect the operation.

syzbot report :

BUG: KASAN: use-after-free in x25_kill_by_device net/x25/af_x25.c:217 [inline]
BUG: KASAN: use-after-free in x25_device_event+0x296/0x2b0 net/x25/af_x25.c:252
Read of size 8 at addr ffff8880a030edd0 by task syz-executor003/7854

CPU: 0 PID: 7854 Comm: syz-executor003 Not tainted 5.0.0+ #97
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 x25_kill_by_device net/x25/af_x25.c:217 [inline]
 x25_device_event+0x296/0x2b0 net/x25/af_x25.c:252
 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:7607
 dev_change_flags+0x10d/0x170 net/core/dev.c:7643
 dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
 dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
 sock_do_ioctl+0x1bd/0x300 net/socket.c:995
 sock_ioctl+0x32b/0x610 net/socket.c:1096
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4467c9
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdbea222d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 00000000004467c9
RDX: 0000000020000340 RSI: 0000000000008914 RDI: 0000000000000003
RBP: 00000000006dbc50 R08: 00007fdbea223700 R09: 0000000000000000
R10: 00007fdbea223700 R11: 0000000000000246 R12: 00000000006dbc5c
R13: 6000030030626669 R14: 0000000000000000 R15: 0000000030626669

Allocated by task 7843:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:509
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3615
 kmalloc include/linux/slab.h:545 [inline]
 x25_link_device_up+0x46/0x3f0 net/x25/x25_link.c:249
 x25_device_event+0x116/0x2b0 net/x25/af_x25.c:242
 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 __dev_notify_flags+0x121/0x2c0 net/core/dev.c:7605
 dev_change_flags+0x10d/0x170 net/core/dev.c:7643
 dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
 dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
 sock_do_ioctl+0x1bd/0x300 net/socket.c:995
 sock_ioctl+0x32b/0x610 net/socket.c:1096
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 7865:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
 __cache_free mm/slab.c:3494 [inline]
 kfree+0xcf/0x230 mm/slab.c:3811
 x25_neigh_put include/net/x25.h:253 [inline]
 x25_connect+0x8d8/0xde0 net/x25/af_x25.c:824
 __sys_connect+0x266/0x330 net/socket.c:1685
 __do_sys_connect net/socket.c:1696 [inline]
 __se_sys_connect net/socket.c:1693 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1693
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a030edc0
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 16 bytes inside of
 256-byte region [ffff8880a030edc0, ffff8880a030eec0)
The buggy address belongs to the page:
page:ffffea000280c380 count:1 mapcount:0 mapping:ffff88812c3f07c0 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea0002806788 ffffea00027f0188 ffff88812c3f07c0
raw: 0000000000000000 ffff8880a030e000 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+04babcefcd396fabec37@syzkaller.appspotmail.com
Cc: andrew hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-10 11:03:59 -07:00
Eric Dumazet 797a22bd52 net/x25: fix a race in x25_bind()
syzbot was able to trigger another soft lockup [1]

I first thought it was the O(N^2) issue I mentioned in my
prior fix (f657d22ee1f "net/x25: do not hold the cpu
too long in x25_new_lci()"), but I eventually found
that x25_bind() was not checking SOCK_ZAPPED state under
socket lock protection.

This means that multiple threads can end up calling
x25_insert_socket() for the same socket, and corrupt x25_list

[1]
watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz-executor.2:10492]
Modules linked in:
irq event stamp: 27515
hardirqs last  enabled at (27514): [<ffffffff81006673>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (27515): [<ffffffff8100668f>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (32): [<ffffffff8632ee73>] x25_get_neigh+0xa3/0xd0 net/x25/x25_link.c:336
softirqs last disabled at (34): [<ffffffff86324bc3>] x25_find_socket+0x23/0x140 net/x25/af_x25.c:341
CPU: 0 PID: 10492 Comm: syz-executor.2 Not tainted 5.0.0-rc7+ #88
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x50 kernel/kcov.c:97
Code: f4 ff ff ff e8 11 9f ea ff 48 c7 05 12 fb e5 08 00 00 00 00 e9 c8 e9 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 <48> 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 38 0c 92 7e 81 e2
RSP: 0018:ffff88806e94fc48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffff1100d84dac5 RBX: 0000000000000001 RCX: ffffc90006197000
RDX: 0000000000040000 RSI: ffffffff86324bf3 RDI: ffff88806c26d628
RBP: ffff88806e94fc48 R08: ffff88806c1c6500 R09: fffffbfff1282561
R10: fffffbfff1282560 R11: ffffffff89412b03 R12: ffff88806c26d628
R13: ffff888090455200 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f3a107e4700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3a107e3db8 CR3: 00000000a5544000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __x25_find_socket net/x25/af_x25.c:327 [inline]
 x25_find_socket+0x7d/0x140 net/x25/af_x25.c:342
 x25_new_lci net/x25/af_x25.c:355 [inline]
 x25_connect+0x380/0xde0 net/x25/af_x25.c:784
 __sys_connect+0x266/0x330 net/socket.c:1662
 __do_sys_connect net/socket.c:1673 [inline]
 __se_sys_connect net/socket.c:1670 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1670
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457e29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3a107e3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e29
RDX: 0000000000000012 RSI: 0000000020000200 RDI: 0000000000000005
RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3a107e46d4
R13: 00000000004be362 R14: 00000000004ceb98 R15: 00000000ffffffff
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10493 Comm: syz-executor.3 Not tainted 5.0.0-rc7+ #88
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
RIP: 0010:queued_write_lock_slowpath+0x143/0x290 kernel/locking/qrwlock.c:86
Code: 4c 8d 2c 01 41 83 c7 03 41 0f b6 45 00 41 38 c7 7c 08 84 c0 0f 85 0c 01 00 00 8b 03 3d 00 01 00 00 74 1a f3 90 41 0f b6 55 00 <41> 38 d7 7c eb 84 d2 74 e7 48 89 df e8 cc aa 4e 00 eb dd be 04 00
RSP: 0018:ffff888085c47bd8 EFLAGS: 00000206
RAX: 0000000000000300 RBX: ffffffff89412b00 RCX: 1ffffffff1282560
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff89412b00
RBP: ffff888085c47c70 R08: 1ffffffff1282560 R09: fffffbfff1282561
R10: fffffbfff1282560 R11: ffffffff89412b03 R12: 00000000000000ff
R13: fffffbfff1282560 R14: 1ffff11010b88f7d R15: 0000000000000003
FS:  00007fdd04086700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd04064db8 CR3: 0000000090be0000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 queued_write_lock include/asm-generic/qrwlock.h:104 [inline]
 do_raw_write_lock+0x1d6/0x290 kernel/locking/spinlock_debug.c:203
 __raw_write_lock_bh include/linux/rwlock_api_smp.h:204 [inline]
 _raw_write_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:312
 x25_insert_socket+0x21/0xe0 net/x25/af_x25.c:267
 x25_bind+0x273/0x340 net/x25/af_x25.c:703
 __sys_bind+0x23f/0x290 net/socket.c:1481
 __do_sys_bind net/socket.c:1492 [inline]
 __se_sys_bind net/socket.c:1490 [inline]
 __x64_sys_bind+0x73/0xb0 net/socket.c:1490
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457e29

Fixes: 90c27297a9 ("X.25 remove bkl in bind")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: andrew hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-23 18:41:06 -08:00
Eric Dumazet cf657d22ee net/x25: do not hold the cpu too long in x25_new_lci()
Due to quadratic behavior of x25_new_lci(), syzbot was able
to trigger an rcu stall.

Fix this by not blocking BH for the whole duration of
the function, and inserting a reschedule point when possible.

If we care enough, using a bitmap could get rid of the quadratic
behavior.

syzbot report :

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu:    0-...!: (10500 ticks this GP) idle=4fa/1/0x4000000000000002 softirq=283376/283376 fqs=0
rcu:     (t=10501 jiffies g=383105 q=136)
rcu: rcu_preempt kthread starved for 10502 jiffies! g383105 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I28928    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803
 rcu_gp_fqs_loop kernel/rcu/tree.c:1948 [inline]
 rcu_gp_kthread+0x956/0x17a0 kernel/rcu/tree.c:2105
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 0
CPU: 0 PID: 8759 Comm: syz-executor2 Not tainted 5.0.0-rc4+ #51
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree.c:1211
 print_cpu_stall kernel/rcu/tree.c:1348 [inline]
 check_cpu_stall kernel/rcu/tree.c:1422 [inline]
 rcu_pending kernel/rcu/tree.c:3018 [inline]
 rcu_check_callbacks.cold+0x500/0xa4a kernel/rcu/tree.c:2521
 update_process_times+0x32/0x80 kernel/time/timer.c:1635
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
 smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline]
RIP: 0010:queued_write_lock_slowpath+0x13e/0x290 kernel/locking/qrwlock.c:86
Code: 00 00 fc ff df 4c 8d 2c 01 41 83 c7 03 41 0f b6 45 00 41 38 c7 7c 08 84 c0 0f 85 0c 01 00 00 8b 03 3d 00 01 00 00 74 1a f3 90 <41> 0f b6 55 00 41 38 d7 7c eb 84 d2 74 e7 48 89 df e8 6c 0f 4f 00
RSP: 0018:ffff88805f117bd8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000300 RBX: ffffffff89413ba0 RCX: 1ffffffff1282774
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff89413ba0
RBP: ffff88805f117c70 R08: 1ffffffff1282774 R09: fffffbfff1282775
R10: fffffbfff1282774 R11: ffffffff89413ba3 R12: 00000000000000ff
R13: fffffbfff1282774 R14: 1ffff1100be22f7d R15: 0000000000000003
 queued_write_lock include/asm-generic/qrwlock.h:104 [inline]
 do_raw_write_lock+0x1d6/0x290 kernel/locking/spinlock_debug.c:203
 __raw_write_lock_bh include/linux/rwlock_api_smp.h:204 [inline]
 _raw_write_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:312
 x25_insert_socket+0x21/0xe0 net/x25/af_x25.c:267
 x25_bind+0x273/0x340 net/x25/af_x25.c:705
 __sys_bind+0x23f/0x290 net/socket.c:1505
 __do_sys_bind net/socket.c:1516 [inline]
 __se_sys_bind net/socket.c:1514 [inline]
 __x64_sys_bind+0x73/0xb0 net/socket.c:1514
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457e39
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fafccd0dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39
RDX: 0000000000000012 RSI: 0000000020000240 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fafccd0e6d4
R13: 00000000004bdf8b R14: 00000000004ce4b8 R15: 00000000ffffffff
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8752 Comm: syz-executor4 Not tainted 5.0.0-rc4+ #51
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__x25_find_socket+0x78/0x120 net/x25/af_x25.c:328
Code: 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 a6 00 00 00 4d 8b 64 24 68 4d 85 e4 74 7f e8 03 97 3d fb 49 83 ec 68 74 74 e8 f8 96 3d fb <49> 8d bc 24 88 04 00 00 48 89 f8 48 c1 e8 03 0f b6 04 18 84 c0 74
RSP: 0018:ffff8880639efc58 EFLAGS: 00000246
RAX: 0000000000040000 RBX: dffffc0000000000 RCX: ffffc9000e677000
RDX: 0000000000040000 RSI: ffffffff863244b8 RDI: ffff88806a764628
RBP: ffff8880639efc80 R08: ffff8880a80d05c0 R09: fffffbfff1282775
R10: fffffbfff1282774 R11: ffffffff89413ba3 R12: ffff88806a7645c0
R13: 0000000000000001 R14: ffff88809f29ac00 R15: 0000000000000000
FS:  00007fe8d0c58700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32823000 CR3: 00000000672eb000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 x25_new_lci net/x25/af_x25.c:357 [inline]
 x25_connect+0x374/0xdf0 net/x25/af_x25.c:786
 __sys_connect+0x266/0x330 net/socket.c:1686
 __do_sys_connect net/socket.c:1697 [inline]
 __se_sys_connect net/socket.c:1694 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1694
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457e39
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe8d0c57c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e39
RDX: 0000000000000012 RSI: 0000000020000200 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8d0c586d4
R13: 00000000004be378 R14: 00000000004ceb00 R15: 00000000ffffffff

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Andrew Hendry <andrew.hendry@gmail.com>
Cc: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-11 13:20:14 -08:00
Martin Schiller b020fcf6bb net/x25: handle call collisions
If a session in X25_STATE_1 (Awaiting Call Accept) receives a call
request, the session will be closed (x25_disconnect), cause=0x01
(Number Busy) and diag=0x48 (Call Collision) will be set and a clear
request will be send.

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-29 14:25:36 -08:00
Martin Schiller 06137619f0 net/x25: fix null_x25_address handling
o x25_find_listener(): the compare for the null_x25_address was wrong.
   We have to check the x25_addr of the listener socket instead of the
   x25_addr of the incomming call.

 o x25_bind(): it was not possible to bind a socket to null_x25_address

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-29 14:25:36 -08:00
Martin Schiller d449ba3d58 net/x25: fix called/calling length calculation in x25_parse_address_block
The length of the called and calling address was not calculated
correctly (BCD encoding).

Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-29 14:25:36 -08:00
Stephen Hemminger 27782f403f x25: remove blank lines at EOF
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-24 14:10:42 -07:00
Linus Torvalds a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00