Miguel reported an skb use after free / double free in vrf_finish_output
when neigh_output returns an error. The vrf driver should return after
the call to neigh_output as it takes over the skb on error path as well.
Patch is a simplified version of Miguel's patch which was written for 4.9,
and updated to top of tree.
Fixes: 8f58336d3f ("net: Add ethernet header for pass through VRF device")
Signed-off-by: Miguel Fadon Perlines <mfadon@teldat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sukumar reported that sends to the local broadcast address
(255.255.255.255) are broken. Check for the address in vrf driver
and do not redirect to the VRF device - similar to multicast
packets.
With this change sockets can use SO_BINDTODEVICE to specify an
egress interface and receive responses. Note: the egress interface
can not be a VRF device but needs to be the enslaved device.
https://bugzilla.kernel.org/show_bug.cgi?id=198521
Reported-by: Sukumar Gopalakrishnan <sukumarg1973@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Files removed in 'net-next' had their license header updated
in 'net'. We take the remove from 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
FRA_L3MDEV is defined as U8, but is being added as a U32 attribute. On
big endian architecture, this results in the l3mdev entry not being
added to the FIB rules.
Fixes: 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add extack arg to netdev_upper_dev_link and netdev_master_upper_dev_link
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass extack to do_set_master and down to ndo_add_slave
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_dst_set(skb, dst) installs a normal (refcounted) dst, there is no
point using skb_dst_force(skb)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When building an allmodconfig kernel with gcc-4.6, we get a rather
odd warning:
drivers/net/vrf.c: In function ‘vrf_ip6_input_dst’:
drivers/net/vrf.c:964:3: error: initialized field with side-effects overwritten [-Werror]
drivers/net/vrf.c:964:3: error: (near initialization for ‘fl6’) [-Werror]
I have no idea what this warning is even trying to say, but it does
seem like a false positive. Reordering the initialization in to match
the structure definition gets rid of the warning, and might also avoid
whatever gcc thinks is wrong here.
Fixes: 9ff7438460 ("net: vrf: Handle ipv6 multicast and link-local addresses")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VRF cached rtable and rt6_info for local traffic are no longer
needed and actually prevent local traffic through enslaved devices.
Remove them.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add extack error messages for failure paths creating vrf devices. Once
extack support is added to iproute2, we go from the unhelpful:
$ ip li add foobar type vrf
RTNETLINK answers: Invalid argument
to:
$ ip li add foobar type vrf
Error: VRF table id is missing
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David 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: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In IPv6 routing code, struct rt6_info is created for each static route
and RTF_CACHE route and inserted into fib6 tree. In both cases, dst
ref count is not taken.
As explained in the previous patch, this leads to the need of the dst
garbage collector.
This patch holds ref count of dst before inserting the route into fib6
tree and properly releases the dst when deleting it from the fib6 tree
as a preparation in order to fully get rid of dst gc later.
Also, correct fib6_age() logic to check dst->__refcnt to be 1 to indicate
no user is referencing the dst.
And remove dst_hold() in vrf_rt6_create() as ip6_dst_alloc() already puts
dst->__refcnt to 1.
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
@@
expression SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- fn(SKB, LEN)[0]
+ *(u8 *)fn(SKB, LEN)
Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
adds the l3mdev FIB rule the first time a VRF device is created. However,
it only creates the rule once and only in the namespace the first device
is created - which may not be init_net. Fix by using the net_generic
capability to make the add_fib_rules flag per network namespace.
Fixes: 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
Reported-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Network devices can allocate reasources and private memory using
netdev_ops->ndo_init(). However, the release of these resources
can occur in one of two different places.
Either netdev_ops->ndo_uninit() or netdev->destructor().
The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.
netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.
netdev->destructor(), on the other hand, does not run until the
netdev references all go away.
Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().
This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.
If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit(). But
it is not able to invoke netdev->destructor().
This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.
However, this means that the resources that would normally be released
by netdev->destructor() will not be.
Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.
Many drivers do not try to deal with this, and instead we have leaks.
Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().
netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().
netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().
Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().
And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codes only deal with the case that the skb is dropped, it
may meet one use-after-free issue when NF_HOOK returns 0 that means
the skb is stolen by one netfilter rule or hook.
When one netfilter rule or hook stoles the skb and return NF_STOLEN,
it means the skb is taken by the rule, and other modules should not
touch this skb ever. Maybe the skb is queued or freed directly by the
rule.
Now uses the nf_hook instead of NF_HOOK to get the result of netfilter,
and check the return value of nf_hook. Only when its value equals 1, it
means the skb could go ahead. Or reset the skb as NULL.
BTW, because vrf_rcv_finish is empty function, so needn't invoke it
even though nf_hook returns 1. But we need to modify vrf_rcv_finish
to deal with the NF_STOLEN case.
There are two cases when skb is stolen.
1. The skb is stolen and freed directly.
There is nothing we need to do, and vrf_rcv_finish isn't invoked.
2. The skb is queued and reinjected again.
The vrf_rcv_finish would be invoked as okfn, so need to free the
skb in it.
Signed-off-by: Gao Feng <gfree.wind@vip.163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Moving the loopback into a VRF breaks networking for the default VRF.
Since the VRF device is the loopback for VRF domains, there is no
reason to move the loopback. Given the repercussions, block attempts
to set lo into a VRF.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A function in kernel/bpf/syscall.c which got a bug fix in 'net'
was moved to kernel/bpf/verifier.c in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add netlink_ext_ack arg to rtnl_doit_func. Pass extack arg to nlmsg_parse
for doit functions that call it directly.
This is the first step to using extended error reporting in rtnetlink.
>From here individual subsystems can be updated to set netlink_ext_ack as
needed.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only need 1 l3mdev FIB rule. Fix setting NLM_F_EXCL in the nlmsghdr.
Fixes: 1aa6c4f6b8 ("net: vrf: Add l3mdev rules on first device create")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/broadcom/genet/bcmmii.c
drivers/net/hyperv/netvsc.c
kernel/bpf/hashtab.c
Almost entirely overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
The VRF driver allows users to implement device based features for an
entire domain. For example, a qdisc or netfilter rules can be attached
to a VRF device or tcpdump can be used to view packets for all devices
in the L3 domain.
The device-based features come with a performance penalty, most
notably in the Tx path. The VRF driver uses the l3mdev_l3_out hook
to switch the dst on an skb to its private dst. This allows the skb
to traverse the xmit stack with the device set to the VRF device
which in turn enables the netfilter and qdisc features. The VRF
driver then performs the FIB lookup again and reinserts the packet.
This patch avoids the redirect for IPv6 packets if a qdisc has not
been attached to a VRF device which is the default config. In this
case the netfilter hooks and network taps are directly traversed in
the l3mdev_l3_out handler. If a qdisc is attached to a VRF device,
then the redirect using the vrf dst is done.
Additional overhead is removed by only checking packet taps if a
socket is open on the device (vrf_dev->ptype_all list is not empty).
Packet sockets bound to any device will still get a copy of the
packet via the real ingress or egress interface.
The end result of this change is a decrease in the overhead of VRF
for the default, baseline case (ie., no netfilter rules, no packet
sockets, no qdisc) from a +3% improvement for UDP which has a lookup
per packet (VRF being better than no l3mdev) to ~2% loss for TCP_CRR
which connects a socket for each request-response.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VRF driver allows users to implement device based features for an
entire domain. For example, a qdisc or netfilter rules can be attached
to a VRF device or tcpdump can be used to view packets for all devices
in the L3 domain.
The device-based features come with a performance penalty, most
notably in the Tx path. The VRF driver uses the l3mdev_l3_out hook
to switch the dst on an skb to its private dst. This allows the skb
to traverse the xmit stack with the device set to the VRF device
which in turn enables the netfilter and qdisc features. The VRF
driver then performs the FIB lookup again and reinserts the packet.
This patch avoids the redirect for IPv4 packets if a qdisc has not
been attached to a VRF device which is the default config. In this
case the netfilter hooks and network taps are directly traversed in
the l3mdev_l3_out handler. If a qdisc is attached to a VRF device,
then the redirect using the vrf dst is done.
Additional overhead is removed by only checking packet taps if a
socket is open on the device (vrf_dev->ptype_all list is not empty).
Packet sockets bound to any device will still get a copy of the
packet via the real ingress or egress interface.
The end result of this change is a decrease in the overhead of VRF
for the default, baseline case (ie., no netfilter rules, no packet
sockets, no qdisc) to ~3% for UDP which has a lookup per packet and
< 1% overhead for connected sockets that leverage early demux and
avoid FIB lookups.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VRF driver takes a reference to the inet6_dev on the VRF device for
its rt6_local dst when handling local traffic through the VRF device as
a loopback. When the device is deleted the driver does a put on the idev
but does not reset rt6i_idev in the rt6_info struct. When the dst is
destroyed, dst_destroy calls ip6_dst_destroy which does a second put for
what is essentially the same reference causing it to be prematurely freed.
Reset rt6i_idev after the put in the vrf driver.
Fixes: b4869aa2f8 ("net: vrf: ipv6 support for local traffic to
local addresses")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow listeners of the subsequent CHANGEUPPER notification to retrieve
the VRF's table ID by calling l3mdev_fib_table() with the slave netdev.
Without this change, the netdev won't be considered an L3 slave and the
function would return 0.
This is consistent with other master device such as bridge and bond that
set the slave's private flag before linking. It also makes
do_vrf_{add,del}_slave() symmetric.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the dst->pending_confirm flag was removed, we do not
need anymore to provide dst arg to dst_neigh_output.
So, rename it to neigh_output as before commit 5110effee8
("net: Do delayed neigh confirmation.").
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add new skbuff flag to allow protocols to confirm neighbour.
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
Add sock_confirm_neigh() helper to confirm the neighbour and
use it for IPv4, IPv6 and VRF before dst_neigh_output.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Frank reported that vrf devices can be created with a table id of 0.
This breaks many of the run time table id checks and should not be
allowed. Detect this condition at create time and fail with EINVAL.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Reported-by: Frank Kellermann <frank.kellermann@atos.net>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib_select_path does not call fib_select_multipath if oif is set in the
flow struct. For VRF use cases oif is always set, so multipath route
selection is bypassed. Use the FLOWI_FLAG_SKIP_NH_OIF to skip the oif
check similar to what is done in fib_table_lookup.
Add saddr and proto to the flow struct for the fib lookup done by the
VRF driver to better match hash computation for a flow.
Fixes: 613d09b30f ("net: Use VRF device index for lookups on TX")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The network device operation for reading statistics is only called
in one place, and it ignores the return value. Having a structure
return value is potentially confusing because some future driver could
incorrectly assume that the return value was used.
Fix all drivers with ndo_get_stats64 to have a void function.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The move from rx-handler to L3 receive handler inadvertantly dropped the
rx counters. Restore them.
Fixes: 74b20582ac ("net: l3mdev: Add hook in ip and ipv6")
Reported-by: Dinesh Dutt <ddutt@cumulusnetworks.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Locally originated traffic in a VRF fails in the presence of a POSTROUTING
rule. For example,
$ iptables -t nat -A POSTROUTING -s 11.1.1.0/24 -j MASQUERADE
$ ping -I red -c1 11.1.1.3
ping: Warning: source address might be selected on device other than red.
PING 11.1.1.3 (11.1.1.3) from 11.1.1.2 red: 56(84) bytes of data.
ping: sendmsg: Operation not permitted
Worse, the above causes random corruption resulting in a panic in random
places (I have not seen a consistent backtrace).
Call nf_reset to drop the conntrack info following the pass through the
VRF device. The nf_reset is needed on Tx but not Rx because of the order
in which NF_HOOK's are hit: on Rx the VRF device is after the real ingress
device and on Tx it is is before the real egress device. Connection
tracking should be tied to the real egress device and not the VRF device.
Fixes: 8f58336d3f ("net: Add ethernet header for pass through VRF device")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Connection tracking with VRF is broken because the pass through the VRF
device drops the connection tracking info. Removing the call to nf_reset
allows DNAT and MASQUERADE to work across interfaces within a VRF.
Fixes: 73e20b761a ("net: vrf: Add support for PREROUTING rules on vrf device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Enable support for IPv4 multicast:
- similar to unicast the flow struct is updated to L3 master device
if relevant prior to calling fib_rules_lookup. The table id is saved
to the lookup arg so the rule action for ipmr can return the table
associated with the device.
- ip_mr_forward needs to check for master device mismatch as well
since the skb->dev is set to it
- allow multicast address on VRF device for Rx by checking for the
daddr in the VRF device as well as the original ingress device
- on Tx need to drop to __mkroute_output when FIB lookup fails for
multicast destination address.
- if CONFIG_IP_MROUTE_MULTIPLE_TABLES is enabled VRF driver creates
IPMR FIB rules on first device create similar to FIB rules. In
addition the VRF driver does not divert IPv4 multicast packets:
it breaks on Tx since the fib lookup fails on the mcast address.
With this patch, ipmr forwarding and local rx/tx work.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.
skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10eca1, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.
The flags field in inet_skb_parm struct needs to be increased to add
another flag. There is currently a 1-byte hole following the flags,
so it can be expanded to u16 without increasing the size of the struct.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No longer used after d66f6c0a8f ("net: ipv4: Remove l3mdev_get_saddr")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Flip the IPv6 output path to use the l3mdev tx out hook. The VRF dst
is not returned on the first FIB lookup. Instead, the dst on the
skb is switched at the beginning of the IPv6 output processing to
send the packet to the VRF driver on xmit.
Link scope addresses (linklocal and multicast) need special handling:
specifically the oif the flow struct can not be changed because we
want the lookup tied to the enslaved interface. ie., the source address
and the returned route MUST point to the interface scope passed in.
Convert the existing vrf_get_rt6_dst to handle only link scope addresses.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Flip the IPv4 output path to use the l3mdev tx out hook. The VRF dst
is not returned on the first FIB lookup. Instead, the dst on the
skb is switched at the beginning of the IPv4 output processing to
send the packet to the VRF driver on xmit.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for PREROUTING rules with skb->dev set to the vrf device.
INPUT rules are already allowed. Provides symmetry with the output path
which allows POSTROUTING rules.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv6 source address selection needs to consider the real egress route.
Similar to IPv4 implement a get_saddr6 method which is called if
source address has not been set. The get_saddr6 method does a full
lookup which means pulling a route from the VRF FIB table and properly
considering linklocal/multicast destination addresses. Lookup failures
(eg., unreachable) then cause the source address selection to fail
which gets propagated back to the caller.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
