Assign a unique proc inode to each namespace, and use that
inode number to ensure we only allocate at most one proc
inode for every namespace in proc.
A single proc inode per namespace allows userspace to test
to see if two processes are in the same namespace.
This has been a long requested feature and only blocked because
a naive implementation would put the id in a global space and
would ultimately require having a namespace for the names of
namespaces, making migration and certain virtualization tricks
impossible.
We still don't have per superblock inode numbers for proc, which
appears necessary for application unaware checkpoint/restart and
migrations (if the application is using namespace file descriptors)
but that is now allowd by the design if it becomes important.
I have preallocated the ipc and uts initial proc inode numbers so
their structures can be statically initialized.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
The user namespace which creates a new network namespace owns that
namespace and all resources created in it. This way we can target
capability checks for privileged operations against network resources to
the user_ns which created the network namespace in which the resource
lives. Privilege to the user namespace which owns the network
namespace, or any parent user namespace thereof, provides the same
privilege to the network resource.
This patch is reworked from a version originally by
Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
The copy of copy_net_ns used when the network stack is not
built is broken as it does not return -EINVAL when attempting
to create a new network namespace. We don't even have
a previous network namespace.
Since we need a copy of copy_net_ns in net/net_namespace.h that is
available when the networking stack is not built at all move the
correct version of copy_net_ns from net_namespace.c into net_namespace.h
Leaving us with just 2 versions of copy_net_ns. One version for when
we compile in network namespace suport and another stub for all other
occasions.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Conflicts:
drivers/net/team/team.c
drivers/net/usb/qmi_wwan.c
net/batman-adv/bat_iv_ogm.c
net/ipv4/fib_frontend.c
net/ipv4/route.c
net/l2tp/l2tp_netlink.c
The team, fib_frontend, route, and l2tp_netlink conflicts were simply
overlapping changes.
qmi_wwan and bat_iv_ogm were of the "use HEAD" variety.
With help from Antonio Quartulli.
Signed-off-by: David S. Miller <davem@davemloft.net>
As pointed by Michal, it is necessary to add a new
namespace for nf_conntrack_reasm code, this prepares
for the second patch.
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Michal Kubeček <mkubecek@suse.cz>
Cc: David Miller <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit prepares the use of rt_genid by both IPv4 and IPv6.
Initialization is left in IPv4 part.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Move the address lists into struct net
- Add per network namespace initialization and cleanup
- Pass around struct net so it is everywhere I need it.
- Rename all of the global variable references into references
to the variables moved into struct net
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As pointed out, there are places, that access net->loopback_dev->ifindex
and after ifindex generation is made per-net this value becomes constant
equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use
it where appropriate.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Strictly speaking this is only _really_ required for checkpoint-restore to
make loopback device always have the same index.
This change appears to be safe wrt "ifindex should be unique per-system"
concept, as all the ifindex usage is either already made per net namespace
of is explicitly limited with init_net only.
There are two cool side effects of this. The first one -- ifindices of
devices in container are always small, regardless of how many containers
we've started (and re-started) so far. The second one is -- we can speed
up the loopback ifidex access as shown in the next patch.
v2: Place ifindex right after dev_base_seq : avoid two holes and use the
same cache line, dirtied in list_netdevice()/unlist_netdevice()
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before this patch sock_diag works for init_net only and dumps
information about sockets from all namespaces.
This patch expands sock_diag for all name-spaces.
It creates a netlink kernel socket for each netns and filters
data during dumping.
v2: filter accoding with netns in all places
remove an unused variable.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Pavel Emelyanov <xemul@parallels.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Randy Dunlap <rdunlap@xenotime.net> reported:
> On 04/23/2012 12:07 AM, Stephen Rothwell wrote:
>
>> Hi all,
>>
>> Changes since 20120420:
>
>
>
> ERROR: "unregister_net_sysctl_table" [net/phonet/phonet.ko] undefined!
> ERROR: "register_net_sysctl" [net/phonet/phonet.ko] undefined!
>
> when CONFIG_SYSCTL is not enabled.
Add static inline stub functions to gracefully handle the case when sysctl
support is not present.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
All of the users have been converted to use registera_net_sysctl so we
no longer need register_net_sysctl.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
register_sysctl_rotable never caught on as an interesting way to
register sysctls. My take on the situation is that what we want are
sysctls that we can only see in the initial network namespace. What we
have implemented with register_sysctl_rotable are sysctls that we can
see in all of the network namespaces and can only change in the initial
network namespace.
That is a very silly way to go. Just register the network sysctls
in the initial network namespace and we don't have any weird special
cases to deal with.
The sysctls affected are:
/proc/sys/net/ipv4/ipfrag_secret_interval
/proc/sys/net/ipv4/ipfrag_max_dist
/proc/sys/net/ipv6/ip6frag_secret_interval
/proc/sys/net/ipv6/mld_max_msf
I really don't expect anyone will miss them if they can't read them in a
child user namespace.
CC: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the netfilter code is modified to use register_net_sysctl_table the
kernel fails to boot because the per net sysctl infrasturce is not setup
soon enough. So to avoid races call net_sysctl_init from sock_init().
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Right now all of the networking sysctl registrations are running in a
compatibiity mode. The natvie sysctl registration api takes a cstring
for a path and a simple ctl_table. Implement register_net_sysctl so
that we can register network sysctls without needing to use
compatiblity code in the sysctl core.
Switching from a ctl_path to a cstring results in less boiler plate
and denser code that is a little easier to read.
I would simply have changed the arguments to register_net_sysctl_table
instead of keeping two functions in parallel but gcc will allow a
ctl_path pointer to be passed to a char * pointer with only issuing a
warning resulting in completely incorrect code can be built. Since I
have to change the function name I am taking advantage of the situation
to let both register_net_sysctl and register_net_sysctl_table live for a
short time in parallel which makes clean conversion patches a bit easier
to read and write.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds a change sequence counter to each net namespace
which is bumped whenever a netdevice is added or removed from
the list. If such a change occurred while a link dump took place,
the dump will have the NLM_F_DUMP_INTR flag set in the first
message which has been interrupted and in all subsequent messages
of the same dump.
Note that links may still be modified or renamed while a dump is
taking place but we can guarantee for userspace to receive a
complete list of links and not miss any.
Testing:
I have added 500 VLAN netdevices to make sure the dump is split
over multiple messages. Then while continuously dumping links in
one process I also continuously deleted and re-added a dummy
netdevice in another process. Multiple dumps per seconds have
had the NLM_F_DUMP_INTR flag set.
I guess we can wait for Johannes patch to hit net-next via the
wireless tree. I just wanted to give this some testing right away.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* new refcount in struct net, controlling actual freeing of the memory
* new method in kobj_ns_type_operations (->drop_ns())
* ->current_ns() semantics change - it's supposed to be followed by
corresponding ->drop_ns(). For struct net in case of CONFIG_NET_NS it bumps
the new refcount; net_drop_ns() decrements it and calls net_free() if the
last reference has been dropped. Method renamed to ->grab_current_ns().
* old net_free() callers call net_drop_ns() instead.
* sysfs_exit_ns() is gone, along with a large part of callchain
leading to it; now that the references stored in ->ns[...] stay valid we
do not need to hunt them down and replace them with NULL. That fixes
problems in sysfs_lookup() and sysfs_readdir(), along with getting rid
of sb->s_instances abuse.
Note that struct net *shutdown* logics has not changed - net_cleanup()
is called exactly when it used to be called. The only thing postponed by
having a sysfs instance refering to that struct net is actual freeing of
memory occupied by struct net.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
net: Kill ratelimit.h dependency in linux/net.h
net: Add linux/sysctl.h includes where needed.
net: Kill ether_table[] declaration.
inetpeer: fix race in unused_list manipulations
atm: expose ATM device index in sysfs
IPVS: bug in ip_vs_ftp, same list heaad used in all netns.
bug.h: Move ratelimit warn interfaces to ratelimit.h
bonding: cleanup module option descriptions
net:8021q:vlan.c Fix pr_info to just give the vlan fullname and version.
net: davinci_emac: fix dev_err use at probe
can: convert to %pK for kptr_restrict support
net: fix ETHTOOL_SFEATURES compatibility with old ethtool_ops.set_flags
netfilter: Fix several warnings in compat_mtw_from_user().
netfilter: ipset: fix ip_set_flush return code
netfilter: ipset: remove unused variable from type_pf_tdel()
netfilter: ipset: Use proper timeout value to jiffies conversion
Several networking headers were depending upon the implicit
linux/sysctl.h include they get when including linux/net.h
Add explicit includes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Take advantage of the new abstraction and allow network devices
to be placed in any network namespace that we have a fd to talk
about.
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Remove include/net/netns/ip_vs.h because it depends on
structures from include/net/ip_vs.h. As ipvs is pointer in
struct net it is better to move struct netns_ipvs into
include/net/ip_vs.h, so that we can easily use other structures
in struct netns_ipvs.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Preparation for network name-space init, in this stage
some empty functions exists.
In most files there is a check if it is root ns i.e. init_net
if (!net_eq(net, &init_net))
return ...
this will be removed by the last patch, when enabling name-space.
*v3
ip_vs_conn.c merge error corrected.
net_ipvs #ifdef removed as sugested by Jan Engelhardt
[ horms@verge.net.au: Removed whitespace-change-only hunks ]
Signed-off-by: Hans Schillstrom <hans.schillstrom@ericsson.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
add __rcu annotation to (struct net)->gen, and use
rcu_dereference_protected() in net_assign_generic()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a network bench, I noticed an unfortunate false sharing between
'loopback_dev' and 'count' fields in "struct net".
'count' is written each time a socket is created or destroyed, while
loopback_dev might be often read in routing code.
Move loopback_dev in a read mostly section of "struct net"
Note: struct netns_xfrm is cache line aligned on SMP.
(It contains a "struct dst_ops")
Move it at the end to avoid holes, and reduce sizeof(struct net) by 128
bytes on ia32.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove INIT_NSPROXY(), use C99 initializer.
Remove INIT_IPC_NS(), INIT_NET_NS() while I'm at it.
Note: headers trim will be done later, now it's quite pointless because
results will be invalidated by merge window.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Add exit_list to struct net to support building lists of network
namespaces to cleanup.
- Add exit_batch to pernet_operations to allow running operations only
once during a network namespace exit. Instead of once per network
namespace.
- Factor opt ops_exit_list and ops_exit_free so the logic with cleanup
up a network namespace does not need to be duplicated.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No that all of the callers have been updated to set fields in
struct pernet_operations, and simplified to let the network
namespace core handle the allocation and freeing of the storage
for them, remove the surpurpflous methods and update the docs
to the new style.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To get the full benefit of batched network namespace cleanup netowrk
device deletion needs to be performed by the generic code. When
using register_pernet_gen_device and freeing the data in exit_net
it is impossible to delay allocation until after exit_net has called
as the device uninit methods are no longer safe.
To correct this, and to simplify working with per network namespace data
I have moved allocation and deletion of per network namespace data into
the network namespace core. The core now frees the data only after
all of the network namespace exit routines have run.
Now it is only required to set the new fields .id and .size
in the pernet_operations structure if you want network namespace
data to be managed for you automatically.
This makes the current register_pernet_gen_device and
register_pernet_gen_subsys routines unnecessary. For the moment
I have left them as compatibility wrappers in net_namespace.h
They will be removed once all of the users have been updated.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is fairly common to kill several network namespaces at once. Either
because they are nested one inside the other or because they are cooperating
in multiple machine networking experiments. As the network stack control logic
does not parallelize easily batch up multiple network namespaces existing
together.
To get the full benefit of batching the virtual network devices to be
removed must be all removed in one batch. For that purpose I have added
a loop after the last network device operations have run that batches
up all remaining network devices and deletes them.
An extra benefit is that the reorganization slightly shrinks the size
of the per network namespace data structures replaceing a work_struct
with a list_head.
In a trivial test with 4K namespaces this change reduced the cost of
a destroying 4K namespaces from 7+ minutes (at 12% cpu) to 44 seconds
(at 60% cpu). The bulk of that 44s was spent in inet_twsk_purge.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When handling large number of netdevice, rtnl_dump_ifinfo()
is very slow because it has O(N^2) complexity.
Instead of scanning one single list, we can use the 256 sub lists
of the dev_index hash table.
This considerably speedups "ip link" operations
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Refactor wext to
* split out iwpriv handling
* split out iwspy handling
* split out procfs support
* allow cfg80211 to have wireless extensions compat code
w/o CONFIG_WIRELESS_EXT
After this, drivers need to
- select WIRELESS_EXT - for wext support
- select WEXT_PRIV - for iwpriv support
- select WEXT_SPY - for iwspy support
except cfg80211 -- which gets new hooks in wext-core.c
and can then get wext handlers without CONFIG_WIRELESS_EXT.
Wireless extensions procfs support is auto-selected
based on PROC_FS and anything that requires the wext core
(i.e. WIRELESS_EXT or CFG80211_WEXT).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Eric explained this to me -- and afterwards the comment
made sense, but not before. Add the the critical point
about interfaces having to be gone from the netns before
subsys notifiers are called.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes wireless extensions netns aware. The
tasklet sending the events is converted to a work
struct so that we can rtnl_lock() in it.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function get_net_ns_by_pid(), to get a network
namespace from a pid_t, will be required in cfg80211
as well. Therefore, let's move it to net_namespace.c
and export it. We can't make it a static inline in
the !NETNS case because it needs to verify that the
given pid even exists (and return -ESRCH).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes generic netlink network namespace aware. No
generic netlink families except for the controller family
are made namespace aware, they need to be checked one by
one and then set the family->netnsok member to true.
A new function genlmsg_multicast_netns() is introduced to
allow sending a multicast message in a given namespace,
for example when it applies to an object that lives in
that namespace, a new function genlmsg_multicast_allns()
to send a message to all network namespaces (for objects
that do not have an associated netns).
The function genlmsg_multicast() is changed to multicast
the message in just init_net, which is currently correct
for all generic netlink families since they only work in
init_net right now. Some will later want to work in all
net namespaces because they do not care about the netns
at all -- those will have to be converted to use one of
the new functions genlmsg_multicast_allns() or
genlmsg_multicast_netns() whenever they are made netns
aware in some way.
After this patch families can easily decide whether or
not they should be available in all net namespaces. Many
genl families us it for objects not related to networking
and should therefore be available in all namespaces, but
that will have to be done on a per family basis.
Note that this doesn't touch on the checkpoint/restart
problem where network namespaces could be used, genl
families and multicast groups are numbered globally and
I see no easy way of changing that, especially since it
must be possible to multicast to all network namespaces
for those families that do not care about netns.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
All we need to take care of is using proper RCU list
add/del primitives and inserting a synchronize_rcu()
at one place to make sure the exit notifiers are run
after everybody has stopped iterating the list.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
It turns out that net_alive is unnecessary, and the original problem
that led to it being added was simply that the icmp code thought
it was a network device and wound up being unable to handle packets
while there were still packets in the network namespace.
Now that icmp and tcp have been fixed to properly register themselves
this problem is no longer present and we have a stronger guarantee
that packets will not arrive in a network namespace then that provided
by net_alive in netif_receive_skb. So remove net_alive allowing
packet reception run a little faster.
Additionally document the strong reason why network namespace cleanup
is safe so that if something happens again someone else will have
a chance of figuring it out.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces two helpers that deal with reading and writing
struct net pointers in various network structures.
Their implementation depends on CONFIG_NET_NS
For symmetry, both functions work with "struct net **pnet".
Their usage should reduce the number of #ifdef CONFIG_NET_NS,
without adding many helpers for each network structure
that hold a "struct net *pointer"
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netns ops which are registered with register_pernet_gen_device() are
shutdown strictly before those which are registered with
register_pernet_subsys(). Sometimes this leads to opposite (read: buggy)
shutdown ordering between two modules.
Add register_pernet_gen_subsys()/unregister_pernet_gen_subsys() for modules
which aren't elite enough for entry in struct net, and which can't use
register_pernet_gen_device(). PPTP conntracking module is such one.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
One comment: #ifdefs around #include is necessary to overcome amazing compile
breakages in NOTRACK-in-netns patch (see below).
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
New object: set of sysctls [currently - root and per-net-ns].
Contains: pointer to parent set, list of tables and "should I see this set?"
method (->is_seen(set)).
Current lists of tables are subsumed by that; net-ns contains such a beast.
->lookup() for ctl_table_root returns pointer to ctl_table_set instead of
that to ->list of that ctl_table_set.
[folded compile fixes by rdd for configs without sysctl]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The only structure declared within is the netns_mib, which will
carry all our mibs within. I didn't put the mibs in the existing
netns_xxx structures to make it possible to mark this one as
properly aligned and get in a separate "read-mostly" cache-line.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This one stores all ctl-heads in one list and restricts the
permissions not give write access to non-init net namespaces.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make release_net/hold_net noop for performance-hungry people. This is a debug
staff and should be used in the debug mode only.
Add check for net != NULL in hold/release calls. This will be required
later on.
[ Added minor simplifications suggested by Brian Haley. -DaveM ]
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the elastic array of void * pointer to the struct net.
The access rules are simple:
1. register the ops with register_pernet_gen_device to get
the id of your private pointer
2. call net_assign_generic() to put the private data on the
struct net (most preferably this should be done in the
->init callback of the ops registered)
3. do not store any private reference on the net_generic array;
4. do not change this pointer while the net is alive;
5. use the net_generic() to get the pointer.
When adding a new pointer, I copy the old array, replace it
with a new one and schedule the old for kfree after an RCU
grace period.
Since the net_generic explores the net->gen array inside rcu
read section and once set the net->gen->ptr[x] pointer never
changes, this grants us a safe access to generic pointers.
Quoting Paul: "... RCU is protecting -only- the net_generic
structure that net_generic() is traversing, and the [pointer]
returned by net_generic() is protected by a reference counter
in the upper-level struct net."
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make some per-net generic pointers, we need some way to address
them, i.e. - IDs. This is simple IDA-based IDs generator for pernet
subsystems.
Addressing questions about potential checkpoint/restart problems:
these IDs are "lite-offsets" within the net structure and are by no
means supposed to be exported to the userspace.
Since it will be used in the nearest future by devices only (tun,
vlan, tunnels, bridge, etc), I make it resemble the functionality
of register_pernet_device().
The new ids is stored in the *id pointer _before_ calling the init
callback to make this id available in this callback.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
According to the overall struct net design, it will be
filled with DCCP-related members.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This does not look good, but there is no other choice. The compilation
without CONFIG_NET is broken and can not be fixed with ease.
After that there is no need for the following commits:
1567ca7eec3edf8fa5cc2d38f9a4f8
Revert them.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's already some stuff on the struct net, that should better
be folded into netns_core structure. I'm making the per-proto inuse
counter be per-net also, which is also a candidate for this, so
introduce this structure and populate it a bit.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce an inline net_eq() to compare two namespaces.
Without CONFIG_NET_NS, since no namespace other than &init_net
exists, it is always 1.
We do not need to convert 1) inline vs inline and
2) inline vs &init_net comparisons.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Current /proc/net is done with so called "shadows", but current
implementation is broken and has little chances to get fixed.
The problem is that dentries subtree of /proc/net directory has
fancy revalidation rules to make processes living in different
net namespaces see different entries in /proc/net subtree, but
currently, tasks see in the /proc/net subdir the contents of any
other namespace, depending on who opened the file first.
The proposed fix is to turn /proc/net into a symlink, which points
to /proc/self/net, which in turn shows what previously was in
/proc/net - the network-related info, from the net namespace the
appropriate task lives in.
# ls -l /proc/net
lrwxrwxrwx 1 root root 8 Mar 5 15:17 /proc/net -> self/net
In other words - this behaves like /proc/mounts, but unlike
"mounts", "net" is not a file, but a directory.
Changes from v2:
* Fixed discrepancy of /proc/net nlink count and selinux labeling
screwup pointed out by Stephen.
To get the correct nlink count the ->getattr callback for /proc/net
is overridden to read one from the net->proc_net entry.
To make selinux still work the net->proc_net entry is initialized
properly, i.e. with the "net" name and the proc_net parent.
Selinux fixes are
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Changes from v1:
* Fixed a task_struct leak in get_proc_task_net, pointed out by Paul.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In fact all we want is per-netns set of rules, however doing that will
unnecessary complicate routines such as ipt_hook()/ipt_do_table, so
make full xt_table array per-netns.
Every user stubbed with init_net for a while.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move static rules_ops & rules_mod_lock to the struct net, register the
pernet subsys to init them and enjoy the fact that the core rules
infrastructure works in the namespace.
Real IPv4 fib rules virtualization requires fib tables support in the
namespace and will be done seriously later in the patchset.
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Like the ipv4 part, this patch adds an ipv6 structure in the net
structure to aggregate the different resources to make ipv6 per
namespace.
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ipv4 will store its parameters inside this structure.
This one is empty now, but it will be eventually filled.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recently David Miller and Herbert Xu pointed out that struct net becomes
overbloated and un-maintainable. There are two solutions:
- provide a pointer to a network subsystem definition from struct net.
This costs an additional dereferrence
- place sub-system definition into the structure itself. This will speedup
run-time access at the cost of recompilation time
The second approach looks better for us. Other sub-systems will follow.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just move the variable on the struct net and adjust
its usage.
Others sysctls from sys.net.core table are more
difficult to virtualize (i.e. make them per-namespace),
but I'll look at them as well a bit later.
Signed-off-by: Pavel Emelyanov <xemul@oenvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Making them per-namespace is required for the following
two reasons:
First, some ctl values have a per-namespace meaning.
Second, making them writable from the sub-namespace
is an isolation hole.
So I introduce the pernet operations to create these
tables. For init_net I use the existing statically
declared tables, for sub-namespace they are duplicated
and the write bits are removed from the mode.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the core.
* add the ctl_table_header on the struct net;
* make the unix_sysctl_register and _unregister clone the table;
* moves calls to them into per-net init and exit callbacks;
* move the .data pointer in the proper place.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will make all the sub-namespaces always use the
default value (10) and leave the tuning via sysctl
to the init namespace only.
Per-namespace tuning is coming.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The user interface is: register_net_sysctl_table and
unregister_net_sysctl_table. Very much like the current
interface except there is a network namespace parameter.
With this any sysctl registered with register_net_sysctl_table
will only show up to tasks in the same network namespace.
All other sysctls continue to be globally visible.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is done by making packet_sklist_lock and packet_sklist per
network namespace and adding an additional filter condition on
received packets to ensure they came from the proper network
namespace.
Changes from v1:
- prohibit to call inet_dgram_ops.ioctl in other than init_net
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After this patch none of the netlink callback support anything
except the initial network namespace but the rtnetlink infrastructure
now handles multiple network namespaces.
Changes from v2:
- IPv6 addrlabel processing
Changes from v1:
- no need for special rtnl_unlock handling
- fixed IPv6 ndisc
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reverts Eric's commit 2b008b0a8e
It diets .text & .data section of the kernel if CONFIG_NET_NS is not set.
This is safe after list operations cleanup.
Signed-of-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the CONFIG_NET_NS is n there's no need in refcounting
the initial net namespace. So relax this code by making a
stupid stubs for the "n" case.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is not safe to to place struct pernet_operations in a special section.
We need struct pernet_operations to last until we call unregister_pernet_subsys.
Which doesn't happen until module unload.
So marking struct pernet_operations is a disaster for modules in two ways.
- We discard it before we call the exit method it points to.
- Because I keep struct pernet_operations on a linked list discarding
it for compiled in code removes elements in the middle of a linked
list and does horrible things for linked insert.
So this looks safe assuming __exit_refok is not discarded
for modules.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the net namespaces many code leaved the __init section,
thus making the kernel occupy more memory than it did before.
Since we have a config option that prohibits the namespace
creation, the functions that initialize/finalize some netns
stuff are simply not needed and can be freed after the boot.
Currently, this is almost not noticeable, since few calls
are no longer in __init, but when the namespaces will be
merged it will be possible to free more code. I propose to
use the __net_init, __net_exit and __net_initdata "attributes"
for functions/variables that are not used if the CONFIG_NET_NS
is not set to save more space in memory.
The exiting functions cannot just reside in the __exit section,
as noticed by David, since the init section will have
references on it and the compilation will fail due to modpost
checks. These references can exist, since the init namespace
never dies and the exit callbacks are never called. So I
introduce the __exit_refok attribute just like it is already
done with the __init_refok.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Denis V. Lunev <den@sw.ru> noticed that the locking rules
for the network namespace list are over complicated and broken.
In particular the current register_netdev_notifier currently
does not take any lock making the for_each_net iteration racy
with network namespace creation and destruction. Oops.
The fact that we need to use for_each_net in rtnl_unlock() when
the rtnetlink support becomes per network namespace makes designing
the proper locking tricky. In addition we need to be able to call
rtnl_lock() and rtnl_unlock() when we have the net_mutex held.
After thinking about it and looking at the alternatives carefully
it looks like the simplest and most maintainable solution is
to remove net_list_mutex altogether, and to use the rtnl_mutex instead.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes loopback_dev per network namespace. Adding
code to create a different loopback device for each network
namespace and adding the code to free a loopback device
when a network namespace exits.
This patch modifies all users the loopback_dev so they
access it as init_net.loopback_dev, keeping all of the
code compiling and working. A later pass will be needed to
update the users to use something other than the initial network
namespace.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows you to create a new network namespace
using sys_clone, or sys_unshare.
As the network namespace is still experimental and under development
clone and unshare support is only made available when CONFIG_NET_NS is
selected at compile time.
As this patch introduces network namespace support into code paths
that exist when the CONFIG_NET is not selected there are a few
additions made to net_namespace.h to allow a few more functions
to be used when the networking stack is not compiled in.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The problem: proc_net files remember which network namespace the are
against but do not remember hold a reference count (as that would pin
the network namespace). So we currently have a small window where
the reference count on a network namespace may be incremented when opening
a /proc file when it has already gone to zero.
To fix this introduce maybe_get_net and get_proc_net.
maybe_get_net increments the network namespace reference count only if it is
greater then zero, ensuring we don't increment a reference count after it
has gone to zero.
get_proc_net handles all of the magic to go from a proc inode to the network
namespace instance and call maybe_get_net on it.
PROC_NET the old accessor is removed so that we don't get confused and use
the wrong helper function.
Then I fix up the callers to use get_proc_net and handle the case case
where get_proc_net returns NULL. In that case I return -ENXIO because
effectively the network namespace has already gone away so the files
we are trying to access don't exist anymore.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When CONFIG_NET=no, init_net is unresolved because net_namespace.c
is not compiled and the include pull init_net definition.
This problem was very similar with the ipc namespace where the kernel
can be compiled with SYSV ipc out.
This patch fix that defining a macro which simply remove init_net
initialization from nsproxy namespace aggregator.
Compiled and booted on qemu-i386 with CONFIG_NET=no and CONFIG_NET=yes.
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes most of the generic device layer network
namespace safe. This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables. The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl
were modified to take a network namespace argument, and
deal with it.
vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.
So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces. The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace. This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.
For now the ifindex generator is left global.
Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.
At the same time there are assumptions in the network stack
that the ifindex of a network device won't change. Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes /proc/net per network namespace. It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.
Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the basic infrastructure needed to support network
namespaces. This infrastructure is:
- Registration functions to support initializing per network
namespace data when a network namespaces is created or destroyed.
- struct net. The network namespace data structure.
This structure will grow as variables are made per network
namespace but this is the minimal starting point.
- Functions to grab a reference to the network namespace.
I provide both get/put functions that keep a network namespace
from being freed. And hold/release functions serve as weak references
and will warn if their count is not zero when the data structure
is freed. Useful for dealing with more complicated data structures
like the ipv4 route cache.
- A list of all of the network namespaces so we can iterate over them.
- A slab for the network namespace data structure allowing leaks
to be spotted.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric W. Biederman