This bug is responsible for causing the infamous "Treason uncloaked"
messages that's been popping up everywhere since the printk was added.
It has usually been blamed on foreign operating systems. However,
some of those reports implicate Linux as both systems are running
Linux or the TCP connection is going across the loopback interface.
In fact, there really is a bug in the Linux TCP header prediction code
that's been there since at least 2.1.8. This bug was tracked down with
help from Dale Blount.
The effect of this bug ranges from harmless "Treason uncloaked"
messages to hung/aborted TCP connections. The details of the bug
and fix is as follows.
When snd_wnd is updated, we only update pred_flags if
tcp_fast_path_check succeeds. When it fails (for example,
when our rcvbuf is used up), we will leave pred_flags with
an out-of-date snd_wnd value.
When the out-of-date pred_flags happens to match the next incoming
packet we will again hit the fast path and use the current snd_wnd
which will be wrong.
In the case of the treason messages, it just happens that the snd_wnd
cached in pred_flags is zero while tp->snd_wnd is non-zero. Therefore
when a zero-window packet comes in we incorrectly conclude that the
window is non-zero.
In fact if the peer continues to send us zero-window pure ACKs we
will continue making the same mistake. It's only when the peer
transmits a zero-window packet with data attached that we get a
chance to snap out of it. This is what triggers the treason
message at the next retransmit timeout.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Although this message is having the intended effect of causing wireless
driver maintainers to upgrade their code, I never should have merged this
patch in its present form. Leading to tons of bug reports and unhappy
users.
Some wireless apps poll for statistics regularly, which leads to a printk()
every single time they ask for stats. That's a little bit _too_ much of a
reminder that the driver is using an old API.
Change this to printing out the message once, per kernel boot.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
James Ketrenos wrote:
> [3/4] Use the tx_headroom and reserve requested space.
This patch introduced a compile problem; patch below corrects this.
Fixed compilation error due to not passing tx_headroom in
ieee80211_tx_frame.
Signed-off-by: James Ketrenos <jketreno@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Fix setting of the broadcast address when the netmask is set via
SIOCSIFNETMASK in Linux 2.6. The code wanted the old value of
ifa->ifa_mask but used it after it had already been overwritten with
the new value.
Signed-off-by: David Engel <gigem@comcast.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Add kernel-doc to skbuff.h, skbuff.c to eliminate kernel-doc warnings.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
skb_prev is assigned from skb, which cannot be NULL. This patch removes the
unnecessary NULL check.
Signed-off-by: Jayachandran C. <c.jayachandran at gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Remove the variable nlk & call to nlk_sk as it does not have any side effect.
Signed-off-by: Jayachandran C. <c.jayachandran at gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Now that we've switched over to storing MTUs in the xfrm_dst entries,
we no longer need the dst's get_mss methods. This patch gets rid of
them.
It also documents the fact that our MTU calculation is not optimal
for ESP.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This patch kills a redundant rcu_dereference on fa->fa_info in fib_trie.c.
As this dereference directly follows a list_for_each_entry_rcu line, we
have already taken a read barrier with respect to getting an entry from
the list.
This read barrier guarantees that all values read out of fa are valid.
In particular, the contents of structure pointed to by fa->fa_info is
initialised before fa->fa_info is actually set (see fn_trie_insert);
the setting of fa->fa_info itself is further separated with a write
barrier from the insertion of fa into the list.
Therefore by taking a read barrier after obtaining fa from the list
(which is given by list_for_each_entry_rcu), we can be sure that
fa->fa_info contains a valid pointer, as well as the fact that the
data pointed to by fa->fa_info is itself valid.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
It's fairly simple to resize the hash table, but currently you need to
remove and reinsert the module. That's bad (we lose connection
state). Harald has even offered to write a daemon which sets this
based on load.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
The code to handle the /proc interface can be cleaned up in several places:
* use seq_file for read
* don't need to remember all the filenames separately
* use for_online_cpu's
* don't vmalloc a buffer for small command from user.
Committer note:
This patch clashed with John Hawkes's "[NET]: Wider use of for_each_*cpu()",
so I fixed it up manually.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
These are cleanup patches for pktgen that can go in 2.6.15
Can use kzalloc in a couple of places.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
pktgen is calling kmalloc GFP_KERNEL and vmalloc with lock held.
The simplest fix is to turn the lock into a semaphore, since the
thread lock is only used for admin control from user context.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
