Because of rounding, in certain conditions, i.e. when in congestion
avoidance state rho is smaller than 1/128 of the current cwnd, TCP
Hybla congestion control starves and the cwnd is kept constant
forever.
This patch forces an increment by one segment after #send_cwnd calls
without increments(newreno behavior).
Signed-off-by: Daniele Lacamera <root@danielinux.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Benjamin Thery tracked down a bug that explains many instances
of the error
unregister_netdevice: waiting for %s to become free. Usage count = %d
It turns out that netdev_run_todo can dead-lock with itself if
a second instance of it is run in a thread that will then free
a reference to the device waited on by the first instance.
The problem is really quite silly. We were trying to create
parallelism where none was required. As netdev_run_todo always
follows a RTNL section, and that todo tasks can only be added
with the RTNL held, by definition you should only need to wait
for the very ones that you've added and be done with it.
There is no need for a second mutex or spinlock.
This is exactly what the following patch does.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Ali Saidi <saidi@engin.umich.edu>
When TCP receive copy offload is enabled it's possible that
tcp_rcv_established() will cause two acks to be sent for a single
packet. In the case that a tcp_dma_early_copy() is successful,
copied_early is set to true which causes tcp_cleanup_rbuf() to be
called early which can send an ack. Further along in
tcp_rcv_established(), __tcp_ack_snd_check() is called and will
schedule a delayed ACK. If no packets are processed before the delayed
ack timer expires the packet will be acked twice.
Signed-off-by: David S. Miller <davem@davemloft.net>
Jesper Dangaard Brouer <hawk@comx.dk> reported a bug when setting a VLAN
device down that is in promiscous mode:
When the VLAN device is set down, the promiscous count on the real
device is decremented by one by vlan_dev_stop(). When removing the
promiscous flag from the VLAN device afterwards, the promiscous
count on the real device is decremented a second time by the
vlan_change_rx_flags() callback.
The root cause for this is that the ->change_rx_flags() callback is
invoked while the device is down. The synchronization is meant to mirror
the behaviour of the ->set_rx_mode callbacks, meaning the ->open function
is responsible for doing a full sync on open, the ->close() function is
responsible for doing full cleanup on ->stop() and ->change_rx_flags()
is meant to do incremental changes while the device is UP.
Only invoke ->change_rx_flags() while the device is UP to provide the
intended behaviour.
Tested-by: Jesper Dangaard Brouer <jdb@comx.dk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
While debugging another bug it was found that NetRom socks
are sometimes seen unorphaned in sk_free(). This patch moves
sock_orphan() in nr_release() to the beginning (like in ax25,
or rose).
Reported-and-tested-by: Bernard Pidoux f6bvp <f6bvp@free.fr>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since we reverted 30902dc3cb ("ax25: Fix
std timer socket destroy handling.") we have to put some kind of fix
in to cure the issue whereby unaccepted connections do not get destroyed.
The approach used here is from Tihomir Heidelberg - 9a4gl
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 30902dc3cb.
It causes all kinds of problems, based upon a report by
Bernard (f6bvp) and analysis by Jarek Poplawski.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a xfrm_{state,policy}_walk leak if pfkey socket is closed while
dumping is on-going.
Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following actions are possible:
tcp_v6_rcv
skb->dev = NULL;
tcp_v6_do_rcv
tcp_v6_hnd_req
tcp_check_req
req->rsk_ops->send_ack == tcp_v6_send_ack
So, skb->dev can be NULL in tcp_v6_send_ack. We must obtain namespace
from dst entry.
Thanks to Vitaliy Gusev <vgusev@openvz.org> for initial problem finding
in IPv4 code.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since call to function sctp_sf_abort_violation() need paramter 'arg' with
'struct sctp_chunk' type, it will read the chunk type and chunk length from
the chunk_hdr member of chunk. But call to sctp_sf_violation_paramlen()
always with 'struct sctp_paramhdr' type's parameter, it will be passed to
sctp_sf_abort_violation(). This may cause kernel panic.
sctp_sf_violation_paramlen()
|-- sctp_sf_abort_violation()
|-- sctp_make_abort_violation()
This patch fixed this problem. This patch also fix two place which called
sctp_sf_violation_paramlen() with wrong paramter type.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We're never supposed to shrink the headroom or tailroom. In fact,
shrinking the headroom is a fatal action.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code ignores rules for internal options in HBH/DST options
header in packet processing if 'Not strict' mode is specified (which is not
implemented). Clearly it is not expected by user.
Kernel should reject HBH/DST rule insertion with 'Not strict' mode
in the first place.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
9p: fix put_data error handling
9p: use an IS_ERR test rather than a NULL test
9p: introduce missing kfree
9p-trans_fd: fix and clean up module init/exit paths
9p-trans_fd: don't do fs segment mangling in p9_fd_poll()
9p-trans_fd: clean up p9_conn_create()
9p-trans_fd: fix trans_fd::p9_conn_destroy()
9p: implement proper trans module refcounting and unregistration
Abhishek Kulkarni pointed out an inconsistency in the way
errors are returned from p9_put_data. On deeper exploration it
seems the error handling for this path was completely wrong.
This patch adds checks for allocation problems and propagates
errors correctly.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Error handling code following a kmalloc should free the allocated data.
The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,l;
position p1,p2;
expression *ptr != NULL;
@@
(
if ((x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...)) == NULL) S
|
x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
)
<... when != x
when != if (...) { <+...x...+> }
x->f = E
...>
(
return \(0\|<+...x...+>\|ptr\);
|
return@p2 ...;
)
@script:python@
p1 << r.p1;
p2 << r.p2;
@@
print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
trans_fd leaked p9_mux_wq on module unload. Fix it. While at it,
collapse p9_mux_global_init() into p9_trans_fd_init(). It's easier to
follow this way and the global poll_tasks array is about to removed
anyway.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
p9_fd_poll() is never called with user pointers and f_op->poll()
doesn't expect its arguments to be from userland. There's no need to
set kernel ds before calling f_op->poll() from p9_fd_poll(). Remove
it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
* Use kzalloc() to allocate p9_conn and remove 0/NULL initializations.
* Clean up error return paths.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
p9_conn_destroy() first kills all current requests by calling
p9_conn_cancel(), then waits for the request list to be cleared by
waiting on p9_conn->equeue. After that, polling is stopped and the
trans is destroyed. This sequence has a few problems.
* Read and write works were never cancelled and the p9_conn can be
destroyed while the works are running as r/w works remove requests
from the list and dereference the p9_conn from them.
* The list emptiness wait using p9_conn->equeue wouldn't trigger
because p9_conn_cancel() always clears all the lists and the only
way the wait can be triggered is to have another task to issue a
request between the slim window between p9_conn_cancel() and the
wait, which isn't safe under the current implementation with or
without the wait.
This patch fixes the problem by first stopping poll, which can
schedule r/w works, first and cancle r/w works which guarantees that
r/w works are not and will not run from that point and then calling
p9_conn_cancel() and do the rest of destruction.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
9p trans modules aren't refcounted nor were they unregistered
properly. Fix it.
* Add 9p_trans_module->owner and reference the module on each trans
instance creation and put it on destruction.
* Protect v9fs_trans_list with a spinlock. This isn't strictly
necessary as the list is manipulated only during module loading /
unloading but it's a good idea to make the API safe.
* Unregister trans modules when the corresponding module is being
unloaded.
* While at it, kill unnecessary EXPORT_SYMBOL on p9_trans_fd_init().
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
The reasons for disabling paccept() are as follows:
* The API is more complex than needed. There is AFAICS no demonstrated
use case that the sigset argument of this syscall serves that couldn't
equally be served by the use of pselect/ppoll/epoll_pwait + traditional
accept(). Roland seems to concur with this opinion
(http://thread.gmane.org/gmane.linux.kernel/723953/focus=732255). I
have (more than once) asked Ulrich to explain otherwise
(http://thread.gmane.org/gmane.linux.kernel/723952/focus=731018), but he
does not respond, so one is left to assume that he doesn't know of such
a case.
* The use of a sigset argument is not consistent with other I/O APIs
that can block on a single file descriptor (e.g., read(), recv(),
connect()).
* The behavior of paccept() when interrupted by a signal is IMO strange:
the kernel restarts the system call if SA_RESTART was set for the
handler. I think that it should not do this -- that it should behave
consistently with paccept()/ppoll()/epoll_pwait(), which never restart,
regardless of SA_RESTART. The reasoning here is that the very purpose
of paccept() is to wait for a connection or a signal, and that
restarting in the latter case is probably never useful. (Note: Roland
disagrees on this point, believing that rather paccept() should be
consistent with accept() in its behavior wrt EINTR
(http://thread.gmane.org/gmane.linux.kernel/723953/focus=732255).)
I believe that instead, a simpler API, consistent with Ulrich's other
recent additions, is preferable:
accept4(int fd, struct sockaddr *sa, socklen_t *salen, ind flags);
(This simpler API was originally proposed by Ulrich:
http://thread.gmane.org/gmane.linux.network/92072)
If this simpler API is added, then if we later decide that the sigset
argument really is required, then a suitable bit in 'flags' could be added
to indicate the presence of the sigset argument.
At this point, I am hoping we either will get a counter-argument from
Ulrich about why we really do need paccept()'s sigset argument, or that he
will resubmit the original accept4() patch.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Alan Cox <alan@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
