dlm: fix error return code in sctp_accept_from_sock()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <

dlm: fix error return code in sctp_accept_from_sock()

Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: remove lock_sock to avoid scheduling while atomic

Before this patch, functions save_callbacks and restore_callbacks
called function lock_sock and release_sock to prevent other processes
from me

dlm: remove lock_sock to avoid scheduling while atomic

Before this patch, functions save_callbacks and restore_callbacks
called function lock_sock and release_sock to prevent other processes
from messing with the struct sock while the callbacks were saved and
restored. However, function add_sock calls write_lock_bh prior to
calling it save_callbacks, which disables preempts. So the call to
lock_sock would try to schedule when we can't schedule.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: don't save callbacks after accept

When DLM calls accept() on a socket, the comm code copies the sk
after we've saved its callbacks. Afterward, it calls add_sock which
saves the callbacks a seco

dlm: don't save callbacks after accept

When DLM calls accept() on a socket, the comm code copies the sk
after we've saved its callbacks. Afterward, it calls add_sock which
saves the callbacks a second time. Since the error reporting function
lowcomms_error_report calls the previous callback too, this results
in a recursive call to itself. This patch adds a new parameter to
function add_sock to tell whether to save the callbacks. Function
tcp_accept_from_sock (and its sctp counterpart) then calls it with
false to avoid the recursion.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: free workqueues after the connections

After backporting commit ee44b4bc054a ("dlm: use sctp 1-to-1 API")
series to a kernel with an older workqueue which didn't use RCU yet, it
was noticed that

dlm: free workqueues after the connections

After backporting commit ee44b4bc054a ("dlm: use sctp 1-to-1 API")
series to a kernel with an older workqueue which didn't use RCU yet, it
was noticed that we are freeing the workqueues in dlm_lowcomms_stop()
too early as free_conn() will try to access that memory for canceling
the queued works if any.

This issue was introduced by commit 0d737a8cfd83 as before it such
attempt to cancel the queued works wasn't performed, so the issue was
not present.

This patch fixes it by simply inverting the free order.

Cc: stable@vger.kernel.org
Fixes: 0d737a8cfd83 ("dlm: fix race while closing connections")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: Use kmemdup instead of kmalloc and memcpy

Replace calls to kmalloc followed by a memcpy with a direct call to
kmemdup.

The Coccinelle semantic patch used to make this change is as follows:
@@

dlm: Use kmemdup instead of kmalloc and memcpy

Replace calls to kmalloc followed by a memcpy with a direct call to
kmemdup.

The Coccinelle semantic patch used to make this change is as follows:
@@
expression from,to,size,flag;
statement S;
@@

- to = \(kmalloc\|kzalloc\)(size,flag);
+ to = kmemdup(from,size,flag);
if (to==NULL || ...) S
- memcpy(to, from, size);

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to impleme

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are
not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

DLM: Save and restore socket callbacks properly

This patch fixes the problems with patch b3a5bbfd7.

1. It removes a return statement from lowcomms_error_report
because it needs to call the origi

DLM: Save and restore socket callbacks properly

This patch fixes the problems with patch b3a5bbfd7.

1. It removes a return statement from lowcomms_error_report
because it needs to call the original error report in all paths
through the function.
2. All socket callbacks are saved and restored, not just the
sk_error_report, and that's done so with proper locking like
sunrpc does.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

DLM: Replace nodeid_to_addr with kernel_getpeername

This patch replaces the call to nodeid_to_addr with a call to
kernel_getpeername. This avoids taking a spinlock because it may
potentially be call

DLM: Replace nodeid_to_addr with kernel_getpeername

This patch replaces the call to nodeid_to_addr with a call to
kernel_getpeername. This avoids taking a spinlock because it may
potentially be called from a softirq context.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA

This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct sock

net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA

This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

dlm: print error from kernel_sendpage

Print a dlm-specific error when a socket error occurs
when sending a dlm message.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigla

dlm: print error from kernel_sendpage

Print a dlm-specific error when a socket error occurs
when sending a dlm message.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: sctp_accept_from_sock() can be static

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David Teigland <teigland@redhat.com>

dlm: fix reconnecting but not sending data

There are cases on which lowcomms_connect_sock() is called directly,
which caused the CF_WRITE_PENDING flag to not bet set upon reconnect,
specially on sen

dlm: fix reconnecting but not sending data

There are cases on which lowcomms_connect_sock() is called directly,
which caused the CF_WRITE_PENDING flag to not bet set upon reconnect,
specially on send_to_sock() error handling. On this last, the flag was
already cleared and no further attempt on transmitting would be done.

As dlm tends to connect when it needs to transmit something, it makes
sense to always mark this flag right after the connect.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: replace BUG_ON with a less severe handling

BUG_ON() is a severe action for this case, specially now that DLM with
SCTP will use 1 socket per association. Instead, we can just close the
socket o

dlm: replace BUG_ON with a less severe handling

BUG_ON() is a severe action for this case, specially now that DLM with
SCTP will use 1 socket per association. Instead, we can just close the
socket on this error condition and return from the function.

Also move the check to an earlier stage as it won't change and thus we
can abort as soon as possible.

Although this issue was reported when still using SCTP with 1-to-many
API, this cleanup wouldn't be that simple back then because we couldn't
close the socket and making sure such event would cease would be hard.
And actually, previous code was closing the association, yet SCTP layer
is still raising the new data event. Probably a bug to be fixed in SCTP.

Reported-by: <tan.hu@zte.com.cn>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: use sctp 1-to-1 API

DLM is using 1-to-many API but in a 1-to-1 fashion. That is, it's not
needed but this causes it to use sctp_do_peeloff() to mimic an
kernel_accept() and this causes a symbol

dlm: use sctp 1-to-1 API

DLM is using 1-to-many API but in a 1-to-1 fashion. That is, it's not
needed but this causes it to use sctp_do_peeloff() to mimic an
kernel_accept() and this causes a symbol dependency on sctp module.

By switching it to 1-to-1 API we can avoid this dependency and also
reduce quite a lot of SCTP-specific code in lowcomms.c.

The caveat is that now DLM won't always use the same src port. It will
choose a random one, just like TCP code. This allows the peers to
attempt simultaneous connections, which now are handled just like for
TCP.

Even more sharing between TCP and SCTP code on DLM is possible, but it
is intentionally left for a later commit.

Note that for using nodes with this commit, you have to have at least
the early fixes on this patchset otherwise it will trigger some issues
on old nodes.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: fix not reconnecting on connecting error handling

If we don't clear that bit, lowcomms_connect_sock() will not schedule
another attempt, and no further attempt will be done.

Signed-off-by: Mar

dlm: fix not reconnecting on connecting error handling

If we don't clear that bit, lowcomms_connect_sock() will not schedule
another attempt, and no further attempt will be done.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: fix race while closing connections

When a connection have issues DLM may need to close it. Therefore we
should also cancel pending workqueues for such connection at that time,
and not just whe

dlm: fix race while closing connections

When a connection have issues DLM may need to close it. Therefore we
should also cancel pending workqueues for such connection at that time,
and not just when dlm is not willing to use this connection anymore.

Also, if we don't clear CF_CONNECT_PENDING flag, the error handling
routines won't be able to re-connect as lowcomms_connect_sock() will
check for it.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: fix connection stealing if using SCTP

When using SCTP and accepting a new connection, DLM currently validates
if the peer trying to connect to it is one of the cluster nodes, but it
doesn't che

dlm: fix connection stealing if using SCTP

When using SCTP and accepting a new connection, DLM currently validates
if the peer trying to connect to it is one of the cluster nodes, but it
doesn't check if it already has a connection to it or not.

If it already had a connection, it will be overwritten, and the new one
will be used for writes, possibly causing the node to leave the cluster
due to communication breakage.

Still, one could DoS the node by attempting N connections and keeping
them open.

As said, but being explicit, both situations are only triggerable from
other cluster nodes, but are doable with only user-level perms.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

net: Add a struct net parameter to sock_create_kern

This is long overdue, and is part of cleaning up how we allocate kernel
sockets that don't reference count struct net.

Signed-off-by: "Eric W. Bi

net: Add a struct net parameter to sock_create_kern

This is long overdue, and is part of cleaning up how we allocate kernel
sockets that don't reference count struct net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

dlm: keep listening connection alive with sctp mode

The connection struct with nodeid 0 is the listening socket,
not a connection to another node. The sctp resend function
was not checking that the

dlm: keep listening connection alive with sctp mode

The connection struct with nodeid 0 is the listening socket,
not a connection to another node. The sctp resend function
was not checking that the nodeid was valid (non-zero), so it
would mistakenly get and resend on the listening connection
when nodeid was zero.

Signed-off-by: Lidong Zhong <lzhong@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

net: Fix use after free by removing length arg from sk_data_ready callbacks.

Several spots in the kernel perform a sequence like:

skb_queue_tail(&sk->s_receive_queue, skb);
sk->sk_data_ready(sk,

net: Fix use after free by removing length arg from sk_data_ready callbacks.

Several spots in the kernel perform a sequence like:

skb_queue_tail(&sk->s_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up. So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument. And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

sctp: remove macros sctp_{lock|release}_sock

Redefined {lock|release}_sock to sctp_{lock|release}_sock for user space friendly
code which we haven't use in years, so removing them.

Signed-off-by: W

sctp: remove macros sctp_{lock|release}_sock

Redefined {lock|release}_sock to sctp_{lock|release}_sock for user space friendly
code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...

dlm: set zero linger time on sctp socket

The recovery time for a failed node was taking a long
time because the failed node could not perform the full
shutdown process. Removing the linger time spe

dlm: set zero linger time on sctp socket

The recovery time for a failed node was taking a long
time because the failed node could not perform the full
shutdown process. Removing the linger time speeds this
up. The dlm does not care what happens to messages to
or from the failed node.

Signed-off-by: Dongmao Zhang <dmzhang@suse.com>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: remove duplicated include from lowcomms.c

Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David Teigland <teigland@redhat.com>

dlm: disable nagle for SCTP

For TCP we disable Nagle and I cannot think of why it would be needed
for SCTP. When disabled it seems to improve dlm_lock operations like it
does for TCP.

Signed-off-by

dlm: disable nagle for SCTP

For TCP we disable Nagle and I cannot think of why it would be needed
for SCTP. When disabled it seems to improve dlm_lock operations like it
does for TCP.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...

dlm: retry failed SCTP sends

Currently if a SCTP send fails, we lose the data we were trying
to send because the writequeue_entry is released when we do the send.
When this happens other nodes will

dlm: retry failed SCTP sends

Currently if a SCTP send fails, we lose the data we were trying
to send because the writequeue_entry is released when we do the send.
When this happens other nodes will then hang waiting for a reply.

This adds support for SCTP to retry the send operation.

I also removed the retry limit for SCTP use, because we want
to make sure we try every path during init time and for longer
failures we want to continually retry in case paths come back up
while trying other paths. We will do this until userspace tells us
to stop.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: David Teigland <teigland@redhat.com>

show more ...