linux-stable.git/include/linux/netfilter.h, branch linux-2.6.24.y

[NETFILTER]: Replace sk_buff ** with sk_buff *

2007-10-15T19:26:29+00:00

With all the users of the double pointers removed, this patch mops up by
finally replacing all occurances of sk_buff ** in the netfilter API by
sk_buff *.

Signed-off-by: Herbert Xu 
Signed-off-by: David S. Miller

[NETFILTER]: Do not copy skb in skb_make_writable

2007-10-15T19:26:27+00:00

Now that all callers of netfilter can guarantee that the skb is not shared,
we no longer have to copy the skb in skb_make_writable.

Signed-off-by: Herbert Xu 
Signed-off-by: David S. Miller

[NETFILTER]: Fix/improve deadlock condition on module removal netfilter

2007-09-11T09:28:26+00:00

So I've had a deadlock reported to me.  I've found that the sequence of
events goes like this:

1) process A (modprobe) runs to remove ip_tables.ko

2) process B (iptables-restore) runs and calls setsockopt on a netfilter socket,
increasing the ip_tables socket_ops use count

3) process A acquires a file lock on the file ip_tables.ko, calls remove_module
in the kernel, which in turn executes the ip_tables module cleanup routine,
which calls nf_unregister_sockopt

4) nf_unregister_sockopt, seeing that the use count is non-zero, puts the
calling process into uninterruptible sleep, expecting the process using the
socket option code to wake it up when it exits the kernel

4) the user of the socket option code (process B) in do_ipt_get_ctl, calls
ipt_find_table_lock, which in this case calls request_module to load
ip_tables_nat.ko

5) request_module forks a copy of modprobe (process C) to load the module and
blocks until modprobe exits.

6) Process C. forked by request_module process the dependencies of
ip_tables_nat.ko, of which ip_tables.ko is one.

7) Process C attempts to lock the request module and all its dependencies, it
blocks when it attempts to lock ip_tables.ko (which was previously locked in
step 3)

Theres not really any great permanent solution to this that I can see, but I've
developed a two part solution that corrects the problem

Part 1) Modifies the nf_sockopt registration code so that, instead of using a
use counter internal to the nf_sockopt_ops structure, we instead use a pointer
to the registering modules owner to do module reference counting when nf_sockopt
calls a modules set/get routine.  This prevents the deadlock by preventing set 4
from happening.

Part 2) Enhances the modprobe utilty so that by default it preforms non-blocking
remove operations (the same way rmmod does), and add an option to explicity
request blocking operation.  So if you select blocking operation in modprobe you
can still cause the above deadlock, but only if you explicity try (and since
root can do any old stupid thing it would like....  :)  ).

Signed-off-by: Neil Horman 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: nfnetlink_queue: don't unregister handler of other subsystem

2007-07-11T05:18:21+00:00

The queue handlers registered by ip[6]_queue.ko at initialization should
not be unregistered according to requests from userland program
using nfnetlink_queue. If we allow that, there is no way to register
the handlers of built-in ip[6]_queue again.

Signed-off-by: Yasuyuki Kozakai 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: nf_conntrack: kill destroy() in struct nf_conntrack for diet

2007-04-26T05:27:45+00:00

The destructor per conntrack is unnecessary, then this replaces it with
system wide destructor.

Signed-off-by: Yasuyuki Kozakai 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: nf_conntrack: don't use nfct in skb if conntrack is disabled

2007-04-26T05:27:44+00:00

Signed-off-by: Yasuyuki Kozakai 
Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: nf_log: minor cleanups

2007-02-12T19:11:55+00:00

- rename nf_logging to nf_loggers since its an array of registered loggers

- rename nf_log_unregister_logger() to nf_log_unregister() to make it
  symetrical to nf_log_register() and convert all users

Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[NETFILTER]: nf_log: make nf_log_unregister_pf return void

2007-02-12T19:11:24+00:00

Since the only user of nf_log_unregister_pf (nfnetlink_log) doesn't
check the return value, change it to void and bail out silently when
a non-existant address family is supplied.

Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller

[PATCH] fix fallout from header dependency trimming

2006-12-04T20:45:29+00:00

OK, that seems to be enough to deal with the mess.

Signed-off-by: Al Viro 
Signed-off-by: Linus Torvalds

netfilter.h needs rcuupdate.h for RCU locking functions

2006-12-04T18:52:29+00:00

This was exposed by Al's recent header file dependency reduction
patches..

Cc: Al Viro 
Cc: David S. Miller 
Signed-off-by: Linus Torvalds