This patch moves some common code that conceptually belongs to the xfrm core
from af_key/xfrm_user into xfrm_alloc_spi.
In particular, the spin lock on the state is now taken inside xfrm_alloc_spi.
Previously it also protected the construction of the response PF_KEY/XFRM
messages to user-space. This is inconsistent as other identical constructions
are not protected by the state lock. This is bad because they in fact should
be protected but only in certain spots (so as not to hold the lock for too
long which may cause packet drops).
The SPI byte order conversion has also been moved.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no point in waking people up when creating/updating larval states
because they'll just go back to sleep again as larval states by definition
cannot be found by xfrm_state_find.
We should only wake them up when the larvals mature or die.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current the x->mode->output functions store the IPv6 nh pointer in the
skb network header. This is inconvenient because the network header then
has to be fixed up before the packet can leave the IPsec stack. The mac
header field is unused on output so we can use that to store this instead.
This patch does that and removes the network header fix-up in xfrm_output.
It also uses ipv6_hdr where appropriate in the x->type->output functions.
There is also a minor clean-up in esp4 to make it use the same code as
esp6 to help any subsequent effort to merge the two.
Lastly it kills two redundant skb_set_* statements in BEET that were
simply copied over from transport mode.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Constructs of the form
xfrm_state_hold(x);
foo(x);
xfrm_state_put(x);
tend to be broken because foo is either synchronous where this is totally
unnecessary or if foo is asynchronous then the reference count is in the
wrong spot.
In the case of xfrm_secpath_reject, the function is synchronous and therefore
we should just kill the reference count.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The lastused update check in xfrm_output can be done just as well in
the mode output function which is specific to RO.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that the only callers of xfrm_replay_notify are in xfrm, we can remove
the export.
This patch also removes xfrm_aevent_doreplay since it's now called in just
one spot.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The replay counter is one of only two remaining things in the output code
that requires a lock on the xfrm state (the other being the crypto). This
patch moves it into the generic xfrm_output so we can remove the lock from
the transforms themselves.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The functions xfrm_state_check and xfrm_state_check_space are only used by
the output code in xfrm_output.c so we can move them over.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most of the code in xfrm4_output_one and xfrm6_output_one are identical so
this patch moves them into a common xfrm_output function which will live
in net/xfrm.
In fact this would seem to fix a bug as on IPv4 we never reset the network
header after a transform which may upset netfilter later on.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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 replaces all occurences to the static variable
loopback_dev to a pointer loopback_dev. That provides the
mindless, trivial, uninteressting change part for the dynamic
allocation for the loopback.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-By: Kirill Korotaev <dev@sw.ru>
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
I was looking at Patrick's fix to inet_diag and it occured
to me that we're using a pointer argument to return values
unnecessarily in netlink_run_queue. Changing it to return
the value will allow the compiler to generate better code
since the value won't have to be memory-backed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Each netlink socket will live in exactly one network namespace,
this includes the controlling kernel sockets.
This patch updates all of the existing netlink protocols
to only support the initial network namespace. Request
by clients in other namespaces will get -ECONREFUSED.
As they would if the kernel did not have the support for
that netlink protocol compiled in.
As each netlink protocol is updated to be multiple network
namespace safe it can register multiple kernel sockets
to acquire a presence in the rest of the network namespaces.
The implementation in af_netlink is a simple filter implementation
at hash table insertion and hash table look up time.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every user of the network device notifiers is either a protocol
stack or a pseudo device. If a protocol stack that does not have
support for multiple network namespaces receives an event for a
device that is not in the initial network namespace it quite possibly
can get confused and do the wrong thing.
To avoid problems until all of the protocol stacks are converted
this patch modifies all netdev event handlers to ignore events on
devices that are not in the initial network namespace.
As the rest of the code is made network namespace aware these
checks can be removed.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch modifies the current ipsec audit layer
by breaking it up into purpose driven audit calls.
So far, the only audit calls made are when add/delete
an SA/policy. It had been discussed to give each
key manager it's own calls to do this, but I found
there to be much redundnacy since they did the exact
same things, except for how they got auid and sid, so I
combined them. The below audit calls can be made by any
key manager. Hopefully, this is ok.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These functions are only used once and are a lot easier to understand if
inlined directly into the function.
Fixes by Masahide NAKAMURA.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
nlmsg_parse() puts attributes at array[type] so the indexing
method can be simpilfied by removing the obscuring "- 1".
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds a policy defining the minimal payload lengths for all the attributes
allowing for most attribute validation checks to be removed from in
the middle of the code path. Makes updates more consistent as many format
errors are recognised earlier, before any changes have been attempted.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Uses nlmsg_parse() to parse the attributes. This actually changes
behaviour as unknown attributes (type > MAXTYPE) no longer cause
an error. Instead unknown attributes will be ignored henceforth
to keep older kernels compatible with more recent userspace tools.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Moves all complex message size calculation into own inlined helper
functions and makes use of the type-safe netlink interface.
Using nlmsg_new() simplifies the calculation itself as it takes care
of the netlink header length by itself.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Moves all of the SUB_POLICY ifdefs related to the attribute size
calculation into a function.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds alg_len() to calculate the properly padded length of an
algorithm attribute to simplify the code.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also makes use of copy_sec_ctx() in another place and removes
duplicated code.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch cleans up duplicate includes in
net/xfrm/
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The security_secid_to_secctx() function returns memory that must be freed
by a call to security_release_secctx() which was not always happening. This
patch fixes two of these problems (all that I could find in the kernel source
at present).
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch modifies the xfrm state selection logic to use the inner
addresses where the outer have been (incorrectly) used. This is
required for beet mode in general and interfamily setups in both
tunnel and beet mode.
Signed-off-by: Joakim Koskela <jookos@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Diego Beltrami <diego.beltrami@gmail.com>
Signed-off-by: Miika Komu <miika@iki.fi>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to the issue we had with template families which
specified the inner families of policies, we need to set
the inner families of states as the main xfrm user Openswan
leaves it as zero.
af_key is unaffected because the inner family is set by it
and not the KM.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
XFRM expects xfrm_dst->u.next to be same pointer as dst->next, which
was broken by the dst_entry reordering in commit 1e19e02c~, causing
an oops in xfrm_bundle_ok when walking the bundle upwards.
Kill xfrm_dst->u.next and change the only user to use dst->next instead.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This allows other in-kernel functions to do SAD lookups.
The only known user at the moment is pktgen.
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
My IPsec MTU optimization patch introduced a regression in MTU calculation
for non-ESP SAs, the SA's header_len needs to be subtracted from the MTU if
the transform doesn't provide a ->get_mtu() function.
Reported-and-tested-by: Marco Berizzi <pupilla@hotmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we check for permission before deleting entries from SAD and
SPD, (see security_xfrm_policy_delete() security_xfrm_state_delete())
However we are not checking for authorization when flushing the SPD and
the SAD completely. It was perhaps missed in the original security hooks
patch.
This patch adds a security check when flushing entries from the SAD and
SPD. It runs the entire database and checks each entry for a denial.
If the process attempting the flush is unable to remove all of the
entries a denial is logged the the flush function returns an error
without removing anything.
This is particularly useful when a process may need to create or delete
its own xfrm entries used for things like labeled networking but that
same process should not be able to delete other entries or flush the
entire database.
Signed-off-by: Joy Latten<latten@austin.ibm.com>
Signed-off-by: Eric Paris <eparis@parisplace.org>
Signed-off-by: James Morris <jmorris@namei.org>
The current IPSEC rule resolution behavior we have does not work for a
lot of people, even though technically it's an improvement from the
-EAGAIN buisness we had before.
Right now we'll block until the key manager resolves the route. That
works for simple cases, but many folks would rather packets get
silently dropped until the key manager resolves the IPSEC rules.
We can't tell these folks to "set the socket non-blocking" because
they don't have control over the non-block setting of things like the
sockets used to resolve DNS deep inside of the resolver libraries in
libc.
With that in mind I coded up the patch below with some help from
Herbert Xu which provides packet-drop behavior during larval state
resolution, controllable via sysctl and off by default.
This lays the framework to either:
1) Make this default at some point or...
2) Move this logic into xfrm{4,6}_policy.c and implement the
ARP-like resolution queue we've all been dreaming of.
The idea would be to queue packets to the policy, then
once the larval state is resolved by the key manager we
re-resolve the route and push the packets out. The
packets would timeout if the rule didn't get resolved
in a certain amount of time.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds some casts to shut up the warnings introduced by my
last patch that added a common interator function for xfrm algorightms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a natural extension of the changeset
[XFRM]: Probe selected algorithm only.
which only removed the probe call for xfrm_user. This patch does exactly
the same thing for af_key. In other words, we load the algorithm requested
by the user rather than everything when adding xfrm states in af_key.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Multi-page allocations are always likely to fail. Since such failures
are expected and non-critical in xfrm_hash_alloc, we shouldn't warn about
them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function xfrm_policy_byid takes a dir argument but finds the policy
using the index instead. We only use the dir argument to update the
policy count for that direction. Since the user can supply any value
for dir, this can corrupt our policy count.
I know this is the problem because a few days ago I was deleting
policies by hand using indicies and accidentally typed in the wrong
direction. It still deleted the policy and at the time I thought
that was cool. In retrospect it isn't such a good idea :)
I decided against letting it delete the policy anyway just in case
we ever remove the connection between indicies and direction.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Aggregate the SPD info TLVs.
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Aggregate the SAD info TLVs.
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
On MIPv6 usage, XFRM sub policy is enabled.
When main (IPsec) and sub (MIPv6) policy selectors have the same
address set but different upper layer information (i.e. protocol
number and its ports or type/code), multiple bundle should be created.
However, currently we have issue to use the same bundle created for
the first time with all flows covered by the case.
It is useful for the bundle to have the upper layer information
to be restructured correctly if it does not match with the flow.
1. Bundle was created by two policies
Selector from another policy is added to xfrm_dst.
If the flow does not match the selector, it goes to slow path to
restructure new bundle by single policy.
2. Bundle was created by one policy
Flow cache is added to xfrm_dst as originated one. If the flow does
not match the cache, it goes to slow path to try searching another
policy.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
With this patch you can use iproute2 in user space to efficiently see
how many policies exist in different directions.
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts eefa390628
The simplification made in that change works with the assumption that
the 'offset' parameter to these functions is always positive or zero,
which is not true. It can be and often is negative in order to access
SKB header values in front of skb->data.
Signed-off-by: David S. Miller <davem@davemloft.net>
This brings the SAD info in sync with net-2.6.22/net-2.6
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
I noticed recently that, in skb_checksum(), "offset" and "start" are
essentially the same thing and have the same value throughout the
function, despite being computed differently. Using a single variable
allows some cleanups and makes the skb_checksum() function smaller,
more readable, and presumably marginally faster.
We appear to have many other "sk_buff walker" functions built on the
exact same model, so the cleanup applies to them, too. Here is a list
of the functions I found to be affected:
net/appletalk/ddp.c:atalk_sum_skb()
net/core/datagram.c:skb_copy_datagram_iovec()
net/core/datagram.c:skb_copy_and_csum_datagram()
net/core/skbuff.c:skb_copy_bits()
net/core/skbuff.c:skb_store_bits()
net/core/skbuff.c:skb_checksum()
net/core/skbuff.c:skb_copy_and_csum_bit()
net/core/user_dma.c:dma_skb_copy_datagram_iovec()
net/xfrm/xfrm_algo.c:skb_icv_walk()
net/xfrm/xfrm_algo.c:skb_to_sgvec()
OTOH, I admit I'm a bit surprised, the cleanup is rather obvious so I'm
really wondering if I am missing something. Can anyone please comment
on this?
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
On a system with a lot of SAs, counting SAD entries chews useful
CPU time since you need to dump the whole SAD to user space;
i.e something like ip xfrm state ls | grep -i src | wc -l
I have seen taking literally minutes on a 40K SAs when the system
is swapping.
With this patch, some of the SAD info (that was already being tracked)
is exposed to user space. i.e you do:
ip xfrm state count
And you get the count; you can also pass -s to the command line and
get the hash info.
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Spring cleaning time...
There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch cb_lock to mutex and allow netlink kernel users to override it
with a subsystem specific mutex for consistent locking in dump callbacks.
All netlink_dump_start users have been audited not to rely on any
side-effects of the previously used spinlock.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the probing based MTU estimation, which usually takes 2-3 iterations
to find a fitting value and may underestimate the MTU, by an exact calculation.
Also fix underestimation of the XFRM trailer_len, which causes unnecessary
reallocations.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move generic skbuff stuff from XFRM code to generic code so that
AF_RXRPC can use it too.
The kdoc comments I've attached to the functions needs to be checked
by whoever wrote them as I had to make some guesses about the workings
of these functions.
Signed-off-By: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that all users of netlink_dump_start() use netlink_run_queue()
to process the receive queue, it is possible to return -EINTR from
netlink_dump_start() directly, therefore simplying the callers.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The error pointer argument in netlink message handlers is used
to signal the special case where processing has to be interrupted
because a dump was started but no error happened. Instead it is
simpler and more clear to return -EINTR and have netlink_run_queue()
deal with getting the queue right.
nfnetlink passed on this error pointer to its subsystem handlers
but only uses it to signal the start of a netlink dump. Therefore
it can be removed there as well.
This patch also cleans up the error handling in the affected
message handlers to be consistent since it had to be touched anyway.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changes netlink_rcv_skb() to skip netlink controll messages and don't
pass them on to the message handler.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
netlink_rcv_skb() is changed to skip messages which don't have the
NLM_F_REQUEST bit to avoid every netlink family having to perform this
check on their own.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)
Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the places where we need a pointer to the transport header, it is
still legal to touch skb->h.raw directly if just adding to,
subtracting from or setting it to another layer header.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Where appropriate, convert references to xtime.tv_sec to the
get_seconds() helper function.
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When sending a security context of 50+ characters in an ACQUIRE
message, following kernel panic occurred.
kernel BUG in xfrm_send_acquire at net/xfrm/xfrm_user.c:1781!
cpu 0x3: Vector: 700 (Program Check) at [c0000000421bb2e0]
pc: c00000000033b074: .xfrm_send_acquire+0x240/0x2c8
lr: c00000000033b014: .xfrm_send_acquire+0x1e0/0x2c8
sp: c0000000421bb560
msr: 8000000000029032
current = 0xc00000000fce8f00
paca = 0xc000000000464b00
pid = 2303, comm = ping
kernel BUG in xfrm_send_acquire at net/xfrm/xfrm_user.c:1781!
enter ? for help
3:mon> t
[c0000000421bb650] c00000000033538c .km_query+0x6c/0xec
[c0000000421bb6f0] c000000000337374 .xfrm_state_find+0x7f4/0xb88
[c0000000421bb7f0] c000000000332350 .xfrm_tmpl_resolve+0xc4/0x21c
[c0000000421bb8d0] c0000000003326e8 .xfrm_lookup+0x1a0/0x5b0
[c0000000421bba00] c0000000002e6ea0 .ip_route_output_flow+0x88/0xb4
[c0000000421bbaa0] c0000000003106d8 .ip4_datagram_connect+0x218/0x374
[c0000000421bbbd0] c00000000031bc00 .inet_dgram_connect+0xac/0xd4
[c0000000421bbc60] c0000000002b11ac .sys_connect+0xd8/0x120
[c0000000421bbd90] c0000000002d38d0 .compat_sys_socketcall+0xdc/0x214
[c0000000421bbe30] c00000000000869c syscall_exit+0x0/0x40
--- Exception: c00 (System Call) at 0000000007f0ca9c
SP (fc0ef8f0) is in userspace
We are using size of security context from xfrm_policy to determine
how much space to alloc skb and then putting security context from
xfrm_state into skb. Should have been using size of security context
from xfrm_state to alloc skb. Following fix does that
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Up until this point we've accepted replay window settings greater than
32 but our bit mask can only accomodate 32 packets. Thus any packet
with a sequence number within the window but outside the bit mask would
be accepted.
This patch causes those packets to be rejected instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Turning up the warnings on gcc makes it emit warnings
about the placement of 'inline' in function declarations.
Here's everything that was under net/
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a space between printing of the src and dst ipv6 addresses.
Otherwise, audit or other test tools may fail to process the audit
record properly because they cannot find the dst address.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I noticed that in xfrm_state_add we look for the larval SA in a few
places without checking for protocol match. So when using both
AH and ESP, whichever one gets added first, deletes the larval SA.
It seems AH always gets added first and ESP is always the larval
SA's protocol since the xfrm->tmpl has it first. Thus causing the
additional km_query()
Adding the check eliminates accidental double SA creation.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Inside pfkey_delete and xfrm_del_sa the audit hooks were not called if
there was any permission/security failures in attempting to do the del
operation (such as permission denied from security_xfrm_state_delete).
This patch moves the audit hook to the exit path such that all failures
(and successes) will actually get audited.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Venkat Yekkirala <vyekkirala@trustedcs.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The security hooks to check permissions to remove an xfrm_policy were
actually done after the policy was removed. Since the unlinking and
deletion are done in xfrm_policy_by* functions this moves the hooks
inside those 2 functions. There we have all the information needed to
do the security check and it can be done before the deletion. Since
auditing requires the result of that security check err has to be passed
back and forth from the xfrm_policy_by* functions.
This patch also fixes a bug where a deletion that failed the security
check could cause improper accounting on the xfrm_policy
(xfrm_get_policy didn't have a put on the exit path for the hold taken
by xfrm_policy_by*)
It also fixes the return code when no policy is found in
xfrm_add_pol_expire. In old code (at least back in the 2.6.18 days) err
wasn't used before the return when no policy is found and so the
initialization would cause err to be ENOENT. But since err has since
been used above when we don't get a policy back from the xfrm_policy_by*
function we would always return 0 instead of the intended ENOENT. Also
fixed some white space damage in the same area.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Venkat Yekkirala <vyekkirala@trustedcs.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As noted by Kent Yoder, this function will always return an
error. Make sure it returns zero on success.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the address family to refer encap_family
when comparing with a kernel generated xfrm_state
Signed-off-by: Kazunori MIYAZAWA <miyazawa@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure that this function is called correctly, and
add BUG() checking to ensure the arguments are sane.
Based upon a patch by Joy Latten.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add CONFIG_NET_KEY_MIGRATE option which makes it possible for user
application to send or receive MIGRATE message to/from PF_KEY socket.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add CONFIG_XFRM_MIGRATE option which makes it possible for for user
application to send or receive MIGRATE message to/from netlink socket.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add user interface for handling XFRM_MSG_MIGRATE. The message is issued
by user application. When kernel receives the message, procedure of
updating XFRM databases will take place.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend the XFRM framework so that endpoint address(es) in the XFRM
databases could be dynamically updated according to a request (MIGRATE
message) from user application. Target XFRM policy is first identified
by the selector in the MIGRATE message. Next, the endpoint addresses
of the matching templates and XFRM states are updated according to
the MIGRATE message.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exports xfrm_state_afinfo.
Signed-off-by: Miika Komu <miika@iki.fi>
Signed-off-by: Diego Beltrami <Diego.Beltrami@hiit.fi>
Signed-off-by: Kazunori Miyazawa <miyazawa@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the entry of Camellia cipher algorithm to ealg_list[].
Signed-off-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The recent hashing introduced an off-by-one bug in policy list insertion.
Instead of adding after the last entry with a lesser or equal priority,
we're adding after the successor of that entry.
This patch fixes this and also adds a warning if we detect a duplicate
entry in the policy list. This should never happen due to this if clause.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
All ->doit handlers want a struct rtattr **, so pass down the right
type.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Installing an IPsec SA using old algorithm names (.compat) does not work
if the algorithm is not already loaded. When not using the PF_KEY
interface, algorithms are not preloaded in xfrm_probe_algs() and
installing a IPsec SA fails.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_ATOMIC is an alias of GFP_ATOMIC
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Disables auditing in ipsec when CONFIG_AUDITSYSCALL is
disabled in the kernel.
Also includes a bug fix for xfrm_state.c as a result of
original ipsec audit patch.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
An audit message occurs when an ipsec SA
or ipsec policy is created/deleted.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change optimizes the dumping of Security policies.
1) Before this change ..
speedopolis:~# time ./ip xf pol
real 0m22.274s
user 0m0.000s
sys 0m22.269s
2) Turn off sub-policies
speedopolis:~# ./ip xf pol
real 0m13.496s
user 0m0.000s
sys 0m13.493s
i suppose the above is to be expected
3) With this change ..
speedopolis:~# time ./ip x policy
real 0m7.901s
user 0m0.008s
sys 0m7.896s
Conflicts:
drivers/ata/libata-scsi.c
include/linux/libata.h
Futher merge of Linus's head and compilation fixups.
Signed-Off-By: David Howells <dhowells@redhat.com>
Conflicts:
drivers/infiniband/core/iwcm.c
drivers/net/chelsio/cxgb2.c
drivers/net/wireless/bcm43xx/bcm43xx_main.c
drivers/net/wireless/prism54/islpci_eth.c
drivers/usb/core/hub.h
drivers/usb/input/hid-core.c
net/core/netpoll.c
Fix up merge failures with Linus's head and fix new compilation failures.
Signed-Off-By: David Howells <dhowells@redhat.com>
Since we never checked the ->family value of templates
before, many applications simply leave it at zero.
Detect this and fix it up to be the pol->family value.
Also, do not clobber xp->family while reading in templates,
that is not necessary.
Signed-off-by: David S. Miller <davem@davemloft.net>
aevents can not uniquely identify an SA. We break the ABI with this
patch, but consensus is that since it is not yet utilized by any
(known) application then it is fine (better do it now than later).
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Miika Komu <miika@iki.fi>
Signed-off-by: Diego Beltrami <Diego.Beltrami@hiit.fi>
Signed-off-by: Kazunori Miyazawa <miyazawa@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Miika Komu <miika@iki.fi>
Signed-off-by: Diego Beltrami <Diego.Beltrami@hiit.fi>
Signed-off-by: Kazunori Miyazawa <miyazawa@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Might as well make flush notifier prettier when subpolicy used
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
The destination PID is passed directly to netlink_unicast()
respectively netlink_multicast().
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make copy_to_user_policy_type take a type instead a policy and
fix its users to pass the type
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the selection of an SA for an outgoing packet to be at the same
context as the originating socket/flow. This eliminates the SELinux
policy's ability to use/sendto SAs with contexts other than the socket's.
With this patch applied, the SELinux policy will require one or more of the
following for a socket to be able to communicate with/without SAs:
1. To enable a socket to communicate without using labeled-IPSec SAs:
allow socket_t unlabeled_t:association { sendto recvfrom }
2. To enable a socket to communicate with labeled-IPSec SAs:
allow socket_t self:association { sendto };
allow socket_t peer_sa_t:association { recvfrom };
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
When application uses XFRM_MSG_GETSA to get state entry through
netlink socket and kernel has no matching one, the application expects
reply message with error status by kernel.
Kernel doesn't send the message back in the case of Mobile IPv6 route
optimization protocols (i.e. routing header or destination options
header). This is caused by incorrect return code "0" from
net/xfrm/xfrm_user.c(xfrm_user_state_lookup) and it makes kernel skip
to acknowledge at net/netlink/af_netlink.c(netlink_rcv_skb).
This patch fix to reply ESRCH to application.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: TAKAMIYA Noriaki <takamiya@po.ntts.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
I actually dont have a test case for these; i just found them by
inspection. Refer to patch "[XFRM]: Sub-policies broke policy events"
for more info
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Acked-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
XFRM policy events are broken when sub-policy feature is turned on.
A simple test to verify this:
run ip xfrm mon on one window and add then delete a policy on another
window ..
Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Acked-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use memcpy() to move xfrm_address_t objects in and out
of netlink messages. The vast majority of xfrm_user was
doing this properly, except for copy_from_user_state()
and copy_to_user_state().
Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm_state_num needs to be increased for XFRM_STATE_ACQ states created
by xfrm_state_find() to prevent the counter from going negative when
the state is destroyed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Missing counter bump when hashing in a new ACQ
xfrm_state.
Now that we have two spots to do the hash grow
check, break it out into a helper function.
Signed-off-by: David S. Miller <davem@davemloft.net>
This treats the security errors encountered in the case of
socket policy matching, the same as how these are treated in
the case of main/sub policies, which is to return a full lookup
failure.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
Currently when an IPSec policy rule doesn't specify a security
context, it is assumed to be "unlabeled" by SELinux, and so
the IPSec policy rule fails to match to a flow that it would
otherwise match to, unless one has explicitly added an SELinux
policy rule allowing the flow to "polmatch" to the "unlabeled"
IPSec policy rules. In the absence of such an explicitly added
SELinux policy rule, the IPSec policy rule fails to match and
so the packet(s) flow in clear text without the otherwise applicable
xfrm(s) applied.
The above SELinux behavior violates the SELinux security notion of
"deny by default" which should actually translate to "encrypt by
default" in the above case.
This was first reported by Evgeniy Polyakov and the way James Morris
was seeing the problem was when connecting via IPsec to a
confined service on an SELinux box (vsftpd), which did not have the
appropriate SELinux policy permissions to send packets via IPsec.
With this patch applied, SELinux "polmatching" of flows Vs. IPSec
policy rules will only come into play when there's a explicit context
specified for the IPSec policy rule (which also means there's corresponding
SELinux policy allowing appropriate domains/flows to polmatch to this context).
Secondly, when a security module is loaded (in this case, SELinux), the
security_xfrm_policy_lookup() hook can return errors other than access denied,
such as -EINVAL. We were not handling that correctly, and in fact
inverting the return logic and propagating a false "ok" back up to
xfrm_lookup(), which then allowed packets to pass as if they were not
associated with an xfrm policy.
The solution for this is to first ensure that errno values are
correctly propagated all the way back up through the various call chains
from security_xfrm_policy_lookup(), and handled correctly.
Then, flow_cache_lookup() is modified, so that if the policy resolver
fails (typically a permission denied via the security module), the flow
cache entry is killed rather than having a null policy assigned (which
indicates that the packet can pass freely). This also forces any future
lookups for the same flow to consult the security module (e.g. SELinux)
for current security policy (rather than, say, caching the error on the
flow cache entry).
This patch: Fix the selinux side of things.
This makes sure SELinux polmatching of flow contexts to IPSec policy
rules comes into play only when an explicit context is associated
with the IPSec policy rule.
Also, this no longer defaults the context of a socket policy to
the context of the socket since the "no explicit context" case
is now handled properly.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
When a security module is loaded (in this case, SELinux), the
security_xfrm_policy_lookup() hook can return an access denied permission
(or other error). We were not handling that correctly, and in fact
inverting the return logic and propagating a false "ok" back up to
xfrm_lookup(), which then allowed packets to pass as if they were not
associated with an xfrm policy.
The way I was seeing the problem was when connecting via IPsec to a
confined service on an SELinux box (vsftpd), which did not have the
appropriate SELinux policy permissions to send packets via IPsec.
The first SYNACK would be blocked, because of an uncached lookup via
flow_cache_lookup(), which would fail to resolve an xfrm policy because
the SELinux policy is checked at that point via the resolver.
However, retransmitted SYNACKs would then find a cached flow entry when
calling into flow_cache_lookup() with a null xfrm policy, which is
interpreted by xfrm_lookup() as the packet not having any associated
policy and similarly to the first case, allowing it to pass without
transformation.
The solution presented here is to first ensure that errno values are
correctly propagated all the way back up through the various call chains
from security_xfrm_policy_lookup(), and handled correctly.
Then, flow_cache_lookup() is modified, so that if the policy resolver
fails (typically a permission denied via the security module), the flow
cache entry is killed rather than having a null policy assigned (which
indicates that the packet can pass freely). This also forces any future
lookups for the same flow to consult the security module (e.g. SELinux)
for current security policy (rather than, say, caching the error on the
flow cache entry).
Signed-off-by: James Morris <jmorris@namei.org>
This patch introduces the BEET mode (Bound End-to-End Tunnel) with as
specified by the ietf draft at the following link:
http://www.ietf.org/internet-drafts/draft-nikander-esp-beet-mode-06.txt
The patch provides only single family support (i.e. inner family =
outer family).
Signed-off-by: Diego Beltrami <diego.beltrami@gmail.com>
Signed-off-by: Miika Komu <miika@iki.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Abhinav Pathak <abhinav.pathak@hiit.fi>
Signed-off-by: Jeff Ahrenholz <ahrenholz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we flush policies, we do a type match so we might not
actually delete all policies matching a certain direction.
So keep track of how many policies we actually kill and
subtract that number from xfrm_policy_count[dir] at the
end.
Based upon a patch by Masahide NAKAMURA.
Signed-off-by: David S. Miller <davem@davemloft.net>
Src hash is introduced for Mobile IPv6 route optimization usage.
On current kenrel code it is calculated with source address only.
It results we uses the same hash value for outbound state (when
the node has only one address for Mobile IPv6).
This patch use also destination address as peer information for
src hash to be dispersed.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SPI=0 is used for acquired IPsec SA and MIPv6 RO state.
Such state should not be added to the SPI hash
because we do not care about it on deleting path.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
spi argument of xfrm_state_lookup() is net-endian
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hashing SAs by source address breaks templates with wildcards as tunnel
source since the source address used for hashing/lookup is still 0/0.
Move source address lookup to xfrm_tmpl_resolve_one() so we can use the
real address in the lookup.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems that during the MIPv6 respin, some code which was originally
conditionally compiled around CONFIG_XFRM_ADVANCED was accidently left
in after the config option was removed.
This patch removes an extraneous pointer (xerr_idxp) which is no
longer needed.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even if we find an exact match in the hash table,
we must inspect the inexact list to look for a match
with a better priority.
Noticed by Masahide NAKAMURA <nakam@linux-ipv6.org>.
Signed-off-by: David S. Miller <davem@davemloft.net>
This idea is from Alexey Kuznetsov.
It is common for policies to be non-prefixed. And for
that case we can optimize lookups, insert, etc. quite
a bit.
For each direction, we have a dynamically sized policy
hash table for non-prefixed policies. We also have a
hash table on policy->index.
For prefixed policies, we have a list per-direction which
we will consult on lookups when a non-prefix hashtable
lookup fails.
This still isn't as efficient as I would like it. There
are four immediate problems:
1) Lots of excessive refcounting, which can be fixed just
like xfrm_state was
2) We do 2 hash probes on insert, one to look for dups and
one to allocate a unique policy->index. Althought I wonder
how much this matters since xfrm_state inserts do up to
3 hash probes and that seems to perform fine.
3) xfrm_policy_insert() is very complex because of the priority
ordering and entry replacement logic.
4) Lots of counter bumping, in addition to policy refcounts,
in the form of xfrm_policy_count[]. This is merely used
to let code path(s) know that some IPSEC rules exist. So
this count is indexed per-direction, maybe that is overkill.
Signed-off-by: David S. Miller <davem@davemloft.net>
The source address is always non-prefixed so we should use
it to help give entropy to the bydst hash.
Signed-off-by: David S. Miller <davem@davemloft.net>
The refcounting done for timers and hash table insertions
are just wasted cycles. We can eliminate all of this
refcounting because:
1) The implicit refcount when the xfrm_state object is active
will always be held while the object is in the hash tables.
We never kfree() the xfrm_state until long after we've made
sure that it has been unhashed.
2) Timers are even easier. Once we mark that x->km.state as
anything other than XFRM_STATE_VALID (__xfrm_state_delete
sets it to XFRM_STATE_DEAD), any timer that fires will
do nothing and return without rearming the timer.
Therefore we can defer the del_timer calls until when the
object is about to be freed up during GC. We have to use
del_timer_sync() and defer it to GC because we can't do
a del_timer_sync() while holding x->lock which all callers
of __xfrm_state_delete hold.
This makes SA changes even more light-weight.
Signed-off-by: David S. Miller <davem@davemloft.net>
Just let GC and other normal mechanisms take care of getting
rid of DST cache references to deleted xfrm_state objects
instead of walking all the policy bundles.
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead, simply set all potentially aliasing existing xfrm_state
objects to have the current generation counter value.
This will make routes get relooked up the next time an existing
route mentioning these aliased xfrm_state objects gets used,
via xfrm_dst_check().
Signed-off-by: David S. Miller <davem@davemloft.net>
Each xfrm_state inserted gets a new generation counter
value. When a bundle is created, the xfrm_dst objects
get the current generation counter of the xfrm_state
they will attach to at dst->xfrm.
xfrm_bundle_ok() will return false if it sees an
xfrm_dst with a generation count different from the
generation count of the xfrm_state that dst points to.
This provides a facility by which to passively and
cheaply invalidate cached IPSEC routes during SA
database changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
The grow algorithm is simple, we grow if:
1) we see a hash chain collision at insert, and
2) we haven't hit the hash size limit (currently 1*1024*1024 slots), and
3) the number of xfrm_state objects is > the current hash mask
All of this needs some tweaking.
Remove __initdata from "hashdist" so we can use it safely at run time.
Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu