It is a followup after the fix in
commit 9c69a13205 ("route: Avoid crash from dereferencing NULL rt->from")
rt6_do_redirect():
1. NULL checking is needed on rt->from because a parallel
fib6_info delete could happen that sets rt->from to NULL.
(e.g. rt6_remove_exception() and fib6_drop_pcpu_from()).
2. fib6_info_hold() is not enough. Same reason as (1).
Meaning, holding dst->__refcnt cannot ensure
rt->from is not NULL or rt->from->fib6_ref is not 0.
Instead of using fib6_info_hold_safe() which ip6_rt_cache_alloc()
is already doing, this patch chooses to extend the rcu section
to keep "from" dereference-able after checking for NULL.
inet6_rtm_getroute():
1. NULL checking is also needed on rt->from for a similar reason.
Note that inet6_rtm_getroute() is using RTNL_FLAG_DOIT_UNLOCKED.
Fixes: a68886a691 ("net/ipv6: Make from in rt6_info rcu protected")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Wei Wang <weiwan@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When there is no route to an IPv6 dest addr, skb_dst(skb) points
to loopback dev in the case of that the IP6CB(skb)->iif is
enslaved to a vrf. This causes Ip6InNoRoutes to be incremented on the
loopback dev. This also causes the lookup to fail on icmpv6_send() and
the dest unreachable to not sent and Ip6OutNoRoutes gets incremented on
the loopback dev.
To reproduce:
* Gateway configuration:
ip link add dev vrf_258 type vrf table 258
ip link set dev enp0s9 master vrf_258
ip addr add 66:1/64 dev enp0s9
ip -6 route add unreachable default metric 8192 table 258
sysctl -w net.ipv6.conf.all.forwarding=1
sysctl -w net.ipv6.conf.enp0s9.forwarding=1
* Sender configuration:
ip addr add 66::2/64 dev enp0s9
ip -6 route add default via 66::1
and ping 67::1 for example from the sender.
Fix this by counting on the original netdev and reset the skb dst to
force a fresh lookup.
v2: Fix typo of destination address in the repro steps.
v3: Simplify the loopback check (per David Ahern) and use reverse
Christmas tree format (per David Miller).
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently have two levels of strict validation:
1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size
The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().
Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.
We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated
Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)
@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)
@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)
For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.
Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.
Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.
In effect then, this adds fully strict validation for any new command.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.
Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().
Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:
@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)
@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nhc_flags holds the RTNH_F flags for a given nexthop (fib{6}_nh).
All of the RTNH_F_ flags fit in an unsigned char, and since the API to
userspace (rtnh_flags and lower byte of rtm_flags) is 1 byte it can not
grow. Make nhc_flags in fib_nh_common an unsigned char and shrink the
size of the struct by 8, from 56 to 48 bytes.
Update the flags arguments for up netdevice events and fib_nexthop_info
which determines the RTNH_F flags to return on a dump/event. The RTNH_F
flags are passed in the lower byte of rtm_flags which is an unsigned int
so use a temp variable for the flags to fib_nexthop_info and combine
with rtm_flags in the caller.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We suspect some issues involving fib6_ref 0 -> 1 transitions might
cause strange syzbot reports.
Lets convert fib6_ref to refcount_t to catch them earlier.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The header contains rtnh_ macros so rename the file accordingly.
Allows a later patch to use the nexthop.h name for the new
nexthop code.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the fib6_flags and fib6_type to fib6_result. Update the lookup helpers
to set them and update post fib lookup users to use the version from the
result.
This allows nexthop objects to have blackhole nexthop.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change fib6_lookup and fib6_table_lookup to take a fib6_result and set
f6i and nh rather than returning a fib6_info. For now both always
return 0.
A later patch set can make these more like the IPv4 counterparts and
return EINVAL, EACCESS, etc based on fib6_type.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change fib6_table_lookup tracepoint to take the fib6_result and use
the fib6_info and fib6_nh from it.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass fib6_result to rt6_select. Instead of returning the fib entry, it
will set f6i and nh based on the lookup.
find_rr_leaf is changed to remove the match option in favor of taking
fib6_result and having __find_rr_leaf set f6i in the result.
In the process, update fib6_info references in __find_rr_leaf to f6i names.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass fib6_result to rt6_device_match with f6i set. rt6_device_match
updates f6i in the result if it finds a better match and sets nh.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ip6_mtu_from_fib6 and fib6_mtu to take a fib6_result over a
fib6_info. Update both to use the fib6_nh from fib6_result.
Since the signature of ip6_mtu_from_fib6 is already changing, add const
to daddr and saddr.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update rt6_insert_exception to take a fib6_result over a fib6_info.
Change ort to f6i from the fib6_result and rename to better reflect
what it references (a fib6_info).
Since this function is already getting changed, update the comments
to reference fib6_info variables rather than the older rt6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that all callers are update to have a fib6_result, pass it down
to ip6_rt_get_dev_rcu, ip6_rt_copy_init, and ip6_rt_init_dst.
In the process, change ort to f6i in ip6_rt_copy_init to make it
clear it is a reference to a fib6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update ip6_rt_pcpu_alloc, rt6_get_pcpu_route and rt6_make_pcpu_route
to a fib6_result over a fib6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ip6_create_rt_rcu to take fib6_result over a fib6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ip6_rt_cache_alloc to take a fib6_result over a fib6_info.
Since ip6_rt_cache_alloc is only the caller, update the
rt6_is_gw_or_nonexthop helper to take fib6_result.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simplify rt6_find_cached_rt for the fast path cases and pass fib6_result
to rt6_find_cached_rt. Rename the local return variable to ret to maintain
consisting with fib6_result name.
Update the comment in rt6_find_cached_rt to reference the new names in
a fib6_info vs the old name when fib entries were an rt6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 'struct fib6_result' to hold the fib entry and fib6_nh from a fib
lookup as separate entries, similar to what IPv4 now has with fib_result.
Rename fib6_multipath_select to fib6_select_path, pass fib6_result to
it, and set f6i and nh in the result once a path selection is done.
Call fib6_select_path unconditionally for path selection which means
moving the sibling and oif check to fib6_select_path. To handle the two
different call paths (2 only call multipath_select if flowi6_oif == 0 and
the other always calls it), add a new have_oif_match that controls the
sibling walk if relevant.
Update callers of fib6_multipath_select accordingly and have them use the
fib6_info and fib6_nh from the result.
This is needed for multipath nexthop objects where a single f6i can
point to multiple fib6_nh (similar to IPv4).
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the review of 0b34eb0043 ("ipv6: Refactor __ip6_route_redirect"),
Martin noted that the flowi6_oif compare is moved to the new helper and
should be removed from __ip6_route_redirect. Fix the oversight.
Fixes: 0b34eb0043 ("ipv6: Refactor __ip6_route_redirect")
Reported-by: Martin Lau <kafai@fb.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the nexthop evaluation of a fib entry to a helper that can be
leveraged for each fib6_nh in a multipath nexthop object.
In the move, 'continue' statements means the helper returns false
(loop should continue) and 'break' means return true (found the entry
of interest).
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the device and gateway checks in the fib6_next loop to a helper
that can be called per fib6_nh entry.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the siblings and fib6_multipath_select after the null entry check
since a null entry can not have siblings.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clean up the fib6_null_entry handling in ip6_pol_route_lookup.
rt6_device_match can return fib6_null_entry, but fib6_multipath_select
can not. Consolidate the fib6_null_entry handling and on the final
null_entry check set rt and goto out - no need to defer to a second
check after rt6_find_cached_rt.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
find_rr_leaf has 3 loops over fib_entries calling find_match. The loops
are very similar with differences in start point and whether the metric
is evaluated:
1. start at rr_head, no extra loop compare, check fib metric
2. start at leaf, compare rt against rr_head, check metric
3. start at cont (potential saved point from earlier loops), no
extra loop compare, no metric check
Create 1 loop that is called 3 different times. This will make a
later change with multipath nexthop objects much simpler.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
find_match primarily needs a fib6_nh (and fib6_flags which it passes
through to rt6_score_route). Move fib6_check_expired up to the call
sites so find_match is only called for relevant entries. Remove the
match argument which is mostly a pass through and use the return
boolean to decide if match gets set in the call sites.
The end result is a helper that can be called per fib6_nh struct
which is needed once fib entries reference nexthop objects that
have more than one fib6_nh.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rt6_score_route only needs the fib6_flags and nexthop data. Change
it accordingly. Allows re-use later for nexthop based fib6_nh.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rt6_probe sends probes for gateways in a nexthop. As such it really
depends on a fib6_nh, not a fib entry. Move last_probe to fib6_nh and
update rt6_probe to a fib6_nh struct.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rt6_check_dev is a simpler helper with only 1 caller. Fold the code
into rt6_score_route.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change rt6_check_neigh to take a fib6_nh instead of a fib entry.
Move the check on fib_flags and whether the nexthop has a gateway
up to the one caller.
Remove the inline from the definition as well. Not necessary.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow the gateway in a fib_nh_common to be from a different address
family than the outer fib{6}_nh. To that end, replace nhc_has_gw with
nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family.
Now nhc_family is used to know if the nh_common is part of a fib_nh
or fib6_nh (used for container_of to get to route family specific data),
and nhc_gw_family represents the address family for the gateway.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Export fib_nexthop_info and fib_add_nexthop for use by IPv6 code.
Remove rt6_nexthop_info and rt6_add_nexthop in favor of the IPv4
versions. Update fib_nexthop_info for IPv6 linkdown check and
RTA_GATEWAY for AF_INET6.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With fib_nh_common in place, move common initialization and release
code into helpers used by both ipv4 and ipv6. For the moment, the init
is just the lwt encap and the release is both the netdev reference and
the the lwt state reference. More will be added later.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add fib_nh_common struct with common nexthop attributes. Convert
fib_nh and fib6_nh to use it. Use macros to move existing
fib_nh_* references to the new nh_common.nhc_*.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename fib6_nh entries that will be moved to a fib_nh_common struct.
Specifically, the device, gateway, flags, and lwtstate are common
with all nexthop definitions. In some places new temporary variables
are declared or local variables renamed to maintain line lengths.
Rename only; no functional change intended.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rt6_add_nexthop and rt6_nexthop_info only need the fib6_info for the
gateway flag and the nexthop weight, and the presence of a gateway is now
per-nexthop. Update the signatures to take a fib6_nh and nexthop weight
and better align with the ipv4 versions.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib6_ignore_linkdown takes a fib6_info but only looks at the net_device
and its IPv6 config. Change it to take a net_device over a fib6_info as
its input argument.
In addition, move it to a header file to make the check inline and usable
later with IPv4 code without going through the ipv6 stub, and rename to
ip6_ignore_linkdown since it is only checking the setting based on the
ipv6 struct on a device.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The gateway setting is not per fib6_info entry but per-fib6_nh. Add a new
fib_nh_has_gw flag to fib6_nh and convert references to RTF_GATEWAY to
the new flag. For IPv6 address the flag is cheaper than checking that
nh_gw is non-0 like IPv4 does.
While this increases fib6_nh by 8-bytes, the effective allocation size of
a fib6_info is unchanged. The 8 bytes is recovered later with a
fib_nh_common change.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the fib6_nh cleanup code to a new helper, fib6_nh_release.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to IPv4, consolidate the fib6_nh initialization into a helper.
As a new standalone function, add a cleanup path to put lwtstate on
error.
To avoid modifying fib6_config flags, move the reject check to a helper
that is invoked once by fib6_nh_init to reset the device and then
again in ip6_route_info_create to set the fib6_flags.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net and null_fallback are redundant. Remove null_fallback in favor of
!net check.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change addrconf_f6i_alloc to generate a fib6_config and call
ip6_route_info_create. addrconf_f6i_alloc is the last caller to
fib6_info_alloc besides ip6_route_info_create, and there is no
reason for it to do its own initialization on a fib6_info.
Host routes need to be created even if the device is down, so add a
new flag, fc_ignore_dev_down, to fib6_config and update fib6_nh_init
to not error out if device is not up.
Notes on the conversion:
- ip_fib_metrics_init is the same as fib6_config has fc_mx set to NULL
and fc_mx_len set to 0
- dst_nocount is handled by the RTF_ADDRCONF flag
- dst_host is handled by fc_dst_len = 128
nh_gw does not get set after the conversion to ip6_route_info_create
but it should not be set in addrconf_f6i_alloc since this is a host
route not a gateway route.
Everything else is a straight forward map between fib6_info and
fib6_config.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ip6_route_info_create is a low level function for ensuring fc_metric is
set. Move the check and default setting to the 2 locations that do not
already set fc_metric before calling ip6_route_info_create. This is
required for the next patch which moves addrconf allocations to
ip6_route_info_create and want the metric for host routes to be 0.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jianlin reported a crash:
[ 381.484332] BUG: unable to handle kernel NULL pointer dereference at 0000000000000068
[ 381.619802] RIP: 0010:fib6_rule_lookup+0xa3/0x160
[ 382.009615] Call Trace:
[ 382.020762] <IRQ>
[ 382.030174] ip6_route_redirect.isra.52+0xc9/0xf0
[ 382.050984] ip6_redirect+0xb6/0xf0
[ 382.066731] icmpv6_notify+0xca/0x190
[ 382.083185] ndisc_redirect_rcv+0x10f/0x160
[ 382.102569] ndisc_rcv+0xfb/0x100
[ 382.117725] icmpv6_rcv+0x3f2/0x520
[ 382.133637] ip6_input_finish+0xbf/0x460
[ 382.151634] ip6_input+0x3b/0xb0
[ 382.166097] ipv6_rcv+0x378/0x4e0
It was caused by the lookup function __ip6_route_redirect() returns NULL in
fib6_rule_lookup() when ip6_create_rt_rcu() returns NULL.
So we fix it by simply making ip6_create_rt_rcu() return ip6_null_entry
instead of NULL.
v1->v2:
- move down 'fallback:' to make it more readable.
Fixes: e873e4b9cc ("ipv6: use fib6_info_hold_safe() when necessary")
Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
