refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

DST_NOCACHE flag check has been removed from dst_release() and
dst_hold_safe() in a previous patch because all the dst are now ref
counted properly and can be released based on refcnt only.
Looking at the rest of the DST_NOCACHE use, all of them can now be
removed or replaced with other checks.
So this patch gets rid of all the DST_NOCACHE usage and remove this flag
completely.
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that all the components have been changed to release dst based on
refcnt only and not depend on dst gc anymore, we can remove the
temporary flag DST_NOGC.

Note that we also need to remove the DST_NOCACHE check in dst_release()
and dst_hold_safe() because now all the dst are released based on refcnt
and behaves as DST_NOCACHE.
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During the creation of xfrm_dst bundle, always take ref count when
allocating the dst. This way, xfrm_bundle_create() will form a linked
list of dst with dst->child pointing to a ref counted dst child. And
the returned dst pointer is also ref counted. This makes the link from
the flow cache to this dst now ref counted properly.
As the dst is always ref counted properly, we can safely mark
DST_NOGC flag so dst_release() will release dst based on refcnt only.
And dst gc is no longer needed and all dst_free() and its related
function calls should be replaced with dst_release() or
dst_release_immediate().

The special handling logic for dst->child in dst_destroy() can be
replaced with a simple dst_release_immediate() call on the child to
release the whole list linked by dst->child pointer.
Previously used DST_NOHASH flag is not needed anymore as well. The
reason that DST_NOHASH is used in the existing code is mainly to prevent
the dst inserted in the fib tree to be wrongly destroyed during the
deletion of the xfrm_dst bundle. So in the existing code, DST_NOHASH
flag is marked in all the dst children except the one which is in the
fib tree.
However, with this patch series to remove dst gc logic and release dst
only based on ref count, it is safe to release all the children from a
xfrm_dst bundle as long as the dst children are all ref counted
properly which is already the case in the existing code.
So, this patch removes the use of DST_NOHASH flag.
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now we will force to do garbage collection if any policy removed in
xfrm_policy_flush(). But during xfrm_net_exit(). We call flow_cache_fini()
first and set set fc->percpu to NULL. Then after we call xfrm_policy_fini()
-> frxm_policy_flush() -> flow_cache_flush(), we will get NULL pointer
dereference when check percpu_empty. The code path looks like:

flow_cache_fini()
  - fc->percpu = NULL
xfrm_policy_fini()
  - xfrm_policy_flush()
    - xfrm_garbage_collect()
      - flow_cache_flush()
        - flow_cache_percpu_empty()
	  - fcp = per_cpu_ptr(fc->percpu, cpu)

To reproduce, just add ipsec in netns and then remove the netns.

v2:
As Xin Long suggested, since only two other places need to call it. move
xfrm_garbage_collect() outside xfrm_policy_flush().

v3:
Fix subject mismatch after v2 fix.

Fixes: 35db0691 ("xfrm: do the garbage collection after flushing policy")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Reviewed-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Add XFRMA_ENCAP, UDP encapsulation port, to km_migrate announcement
to userland. Only add if XFRMA_ENCAP was in user migrate request.
Signed-off-by: NAntony Antony <antony@phenome.org>
Reviewed-by: NRichard Guy Briggs <rgb@tricolour.ca>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Add UDP encapsulation port to XFRM_MSG_MIGRATE using an optional
netlink attribute XFRMA_ENCAP.

The devices that support IKE MOBIKE extension (RFC-4555 Section 3.8)
could go to sleep for a few minutes and wake up. When it wake up the
NAT mapping could have expired, the device send a MOBIKE UPDATE_SA
message to migrate the IPsec SA. The change could be a change UDP
encapsulation port, IP address, or both.
Reported-by: NPaul Wouters <pwouters@redhat.com>
Signed-off-by: NAntony Antony <antony@phenome.org>
Reviewed-by: NRichard Guy Briggs <rgb@tricolour.ca>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

In commit d77e38e6 ("xfrm: Add an IPsec hardware offloading API") we
make xfrm_device.o only compiled when enable option CONFIG_XFRM_OFFLOAD.
But this will make xfrm_dev_event() missing if we only enable default XFRM
options.

Then if we set down and unregister an interface with IPsec on it. there
will no xfrm_garbage_collect(), which will cause dev usage count hold and
get error like:

unregister_netdevice: waiting for <dev> to become free. Usage count = 4

Fixes: d77e38e6 ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

During xfrm migration copy replay and preplay sequence numbers
from the previous state.

Here is a tcpdump output showing the problem.
10.0.10.46 is running vanilla kernel, is the IKE/IPsec responder.
After the migration it sent wrong sequence number, reset to 1.
The migration is from 10.0.0.52 to 10.0.0.53.

IP 10.0.0.52.4500 > 10.0.10.46.4500: UDP-encap: ESP(spi=0x43ef462d,seq=0x7cf), length 136
IP 10.0.10.46.4500 > 10.0.0.52.4500: UDP-encap: ESP(spi=0xca1c282d,seq=0x7cf), length 136
IP 10.0.0.52.4500 > 10.0.10.46.4500: UDP-encap: ESP(spi=0x43ef462d,seq=0x7d0), length 136
IP 10.0.10.46.4500 > 10.0.0.52.4500: UDP-encap: ESP(spi=0xca1c282d,seq=0x7d0), length 136

IP 10.0.0.53.4500 > 10.0.10.46.4500: NONESP-encap: isakmp: child_sa  inf2[I]
IP 10.0.10.46.4500 > 10.0.0.53.4500: NONESP-encap: isakmp: child_sa  inf2[R]
IP 10.0.0.53.4500 > 10.0.10.46.4500: NONESP-encap: isakmp: child_sa  inf2[I]
IP 10.0.10.46.4500 > 10.0.0.53.4500: NONESP-encap: isakmp: child_sa  inf2[R]

IP 10.0.0.53.4500 > 10.0.10.46.4500: UDP-encap: ESP(spi=0x43ef462d,seq=0x7d1), length 136

NOTE: next sequence is wrong 0x1

IP 10.0.10.46.4500 > 10.0.0.53.4500: UDP-encap: ESP(spi=0xca1c282d,seq=0x1), length 136
IP 10.0.0.53.4500 > 10.0.10.46.4500: UDP-encap: ESP(spi=0x43ef462d,seq=0x7d2), length 136
IP 10.0.10.46.4500 > 10.0.0.53.4500: UDP-encap: ESP(spi=0xca1c282d,seq=0x2), length 136
Signed-off-by: NAntony Antony <antony@phenome.org>
Reviewed-by: NRichard Guy Briggs <rgb@tricolour.ca>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Fixes the following sparse warning:

net/xfrm/xfrm_device.c:141:5: warning:
 symbol 'xfrm_dev_register' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Use memdup_user() helper instead of open-coding to simplify the code.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Upon NETDEV_DOWN event, all xfrm_state objects which are bound to
the device are flushed.

The condition for this is wrong, though, testing dev->hw_features
instead of dev->features. If a device has non-user-modifiable
NETIF_F_HW_ESP, then its xfrm_state objects are not flushed,
causing a crash later on after the device is deleted.

Check dev->features instead of dev->hw_features.

Fixes: d77e38e6 ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

When CONFIG_XFRM_SUB_POLICY=y, xfrm_dst stores a copy of the flowi for
that dst. Unfortunately, the code that allocates and fills this copy
doesn't care about what type of flowi (flowi, flowi4, flowi6) gets
passed. In multiple code paths (from raw_sendmsg, from TCP when
replying to a FIN, in vxlan, geneve, and gre), the flowi that gets
passed to xfrm is actually an on-stack flowi4, so we end up reading
stuff from the stack past the end of the flowi4 struct.

Since xfrm_dst->origin isn't used anywhere following commit
ca116922 ("xfrm: Eliminate "fl" and "pol" args to
xfrm_bundle_ok()."), just get rid of it.  xfrm_dst->partner isn't used
either, so get rid of that too.

Fixes: 9d6ec938 ("ipv4: Use flowi4 in public route lookup interfaces.")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Current code silently ignores driver errors when configuring
IPSec offload xfrm_state, and falls back to host-based crypto.

Fail the xfrm_state creation if the driver has an error, because
the NIC offloading was explicitly requested by the user program.

This will communicate back to the user that there was an error.

Fixes: d77e38e6 ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In xfrm_input() when called from GRO, async == 0, and we end up
skipping the processing in xfrm4_transport_finish(). GRO path will
always skip the NF_HOOK, so we don't need the special-case for
!NETFILTER during GRO processing.

Fixes: 7785bba2 ("esp: Add a software GRO codepath")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Now xfrm garbage collection can be triggered by 'ip xfrm policy del'.
These is no reason not to do it after flushing policies, especially
considering that 'garbage collection deferred' is only triggered
when it reaches gc_thresh.

It's no good that the policy is gone but the xdst still hold there.
The worse thing is that xdst->route/orig_dst is also hold and can
not be released even if the orig_dst is already expired.

This patch is to do the garbage collection if there is any policy
removed in xfrm_policy_flush.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

On IPsec hardware offloading, we already get a secpath with
valid state attached when the packet enters the GRO handlers.
So check for hardware offload and skip the state lookup in this
case.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Both esp4 and esp6 used to assume that the SKB payload is encrypted
and therefore the inner_network and inner_transport offsets are
not relevant.
When doing crypto offload in the NIC, this is no longer the case
and the NIC driver needs these offsets so it can do TX TCP checksum
offloading.
This patch sets the inner_network and inner_transport members of
the SKB, as well as encapsulation, to reflect the actual positions
of these headers, and removes them only once encryption is done
on the payload.
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

When we do IPsec offloading, we need a fallback for
packets that were targeted to be IPsec offloaded but
rerouted to a device that does not support IPsec offload.
For that we add a function that checks the offloading
features of the sending device and and flags the
requirement of a fallback before it calls the IPsec
output function. The IPsec output function adds the IPsec
trailer and does encryption if needed.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch adds functions that handles IPsec sequence
numbers for GSO segments and TSO offloading. We need
to calculate and update the sequence numbers based
on the segments that GSO/TSO will generate. We need
this to keep software and hardware sequence number
counter in sync.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch extends the xfrm_type by an encap function pointer
and implements esp4_gso_encap and esp6_gso_encap. These functions
doing the basic esp encapsulation for a GSO packet. In case the
GSO packet needs to be segmented in software, we add gso_segment
functions. This codepath is going to be used on esp hardware
offloads.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch adds all the bits that are needed to do
IPsec hardware offload for IPsec states and ESP packets.
We add xfrmdev_ops to the net_device. xfrmdev_ops has
function pointers that are needed to manage the xfrm
states in the hardware and to do a per packet
offloading decision.

Joint work with:
Ilan Tayari <ilant@mellanox.com>
Guy Shapiro <guysh@mellanox.com>
Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: NGuy Shapiro <guysh@mellanox.com>
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NYossi Kuperman <yossiku@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This is needed for the upcomming IPsec device offloading.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We add a struct  xfrm_type_offload so that we have the offloaded
codepath separated to the non offloaded codepath. With this the
non offloade and the offloaded codepath can coexist.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This is an add-on to the previous patch that passes the extended ACK
structure where it's already available by existing genl_info or extack
function arguments.

This was done with this spatch (with some manual adjustment of
indentation):

@@
expression A, B, C, D, E;
identifier fn, info;
@@
fn(..., struct genl_info *info, ...) {
...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, info->extack)
...
}

@@
expression A, B, C, D, E;
identifier fn, info;
@@
fn(..., struct genl_info *info, ...) {
<...
-nla_parse_nested(A, B, C, D, NULL)
+nla_parse_nested(A, B, C, D, info->extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_parse(A, B, C, D, E, NULL)
+nla_parse(A, B, C, D, E, extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, extack)
...
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_parse_nested(A, B, C, D, NULL)
+nla_parse_nested(A, B, C, D, extack)
...>
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nlmsg_validate(A, B, C, D, NULL)
+nlmsg_validate(A, B, C, D, extack)
...>
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_validate(A, B, C, D, NULL)
+nla_validate(A, B, C, D, extack)
...>
}

@@
expression A, B, C;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_validate_nested(A, B, C, NULL)
+nla_validate_nested(A, B, C, extack)
...>
}
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the base infrastructure and UAPI for netlink extended ACK
reporting. All "manual" calls to netlink_ack() pass NULL for now and
thus don't get extended ACK reporting.

Big thanks goes to Pablo Neira Ayuso for not only bringing up the
whole topic at netconf (again) but also coming up with the nlattr
passing trick and various other ideas.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Reviewed-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the xfrm_user code to use the actual array size
rather than the hard-coded CRYPTO_MAX_ALG_NAME length.  This is
because the array size is fixed at 64 bytes while we want to increase
the in-kernel CRYPTO_MAX_ALG_NAME value.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NAlexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: NAlexander Sverdlin <alexander.sverdlin@nokia.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>

Kees Cook has pointed out that xfrm_replay_state_esn_len() is subject to
wrapping issues.  To ensure we are correctly ensuring that the two ESN
structures are the same size compare both the overall size as reported
by xfrm_replay_state_esn_len() and the internal length are the same.

CVE-2017-7184
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a new xfrm state is created during an XFRM_MSG_NEWSA call we
validate the user supplied replay_esn to ensure that the size is valid
and to ensure that the replay_window size is within the allocated
buffer.  However later it is possible to update this replay_esn via a
XFRM_MSG_NEWAE call.  There we again validate the size of the supplied
buffer matches the existing state and if so inject the contents.  We do
not at this point check that the replay_window is within the allocated
memory.  This leads to out-of-bounds reads and writes triggered by
netlink packets.  This leads to memory corruption and the potential for
priviledge escalation.

We already attempt to validate the incoming replay information in
xfrm_new_ae() via xfrm_replay_verify_len().  This confirms that the user
is not trying to change the size of the replay state buffer which
includes the replay_esn.  It however does not check the replay_window
remains within that buffer.  Add validation of the contained
replay_window.

CVE-2017-7184
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

x86_64 is zero-extending arch so "unsigned int" is preferred over "int"
for address calculations.

Space savings:

	add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-58 (-58)
	function                                     old     new   delta
	xfrm_hash_resize                            2752    2743      -9
	policy_hash_bysel                            985     973     -12
	policy_hash_direct                          1036     999     -37
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Fix xfrm_neigh_lookup to provide dst->path to the
neigh_lookup dst_ops method.

When skb is provided, the IP address in packet should already
match the dst->path address family. But for the non-skb case,
we should consider the last tunnel address as nexthop address.

Fixes: f894cbf8 ("net: Add optional SKB arg to dst_ops->neigh_lookup().")
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds GRO ifrastructure and callbacks for ESP on
ipv4 and ipv6.

In case the GRO layer detects an ESP packet, the
esp{4,6}_gro_receive() function does a xfrm state lookup
and calls the xfrm input layer if it finds a matching state.
The packet will be decapsulated and reinjected it into layer 2.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We need to keep per packet offloading informations across
the layers. So we extend the sec_path to carry these for
the input and output offload codepath.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We need it in the ESP offload handlers, so export it.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The upcomming IPsec ESP gro callbacks will consume the skb,
so prepare for that.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Add a new helper to set the secpath to the skb.
This avoids code duplication, as this is used
in multiple places.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

On IPv4-mapped IPv6 addresses sk_family is AF_INET6,
but the flow informations are created based on AF_INET.
So the routing set up 'struct flowi4' but we try to
access 'struct flowi6' what leads to an out of bounds
access. Fix this by using the family we get with the
dst_entry, like we do it for the standard policy lookup.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>