It was first reported and reproduced by Petr (thanks!) in
https://bugzilla.kernel.org/show_bug.cgi?id=119581
free_percpu(rt->rt6i_pcpu) used to always happen in ip6_dst_destroy().
However, after fixing a deadlock bug in
commit 9c7370a166 ("ipv6: Fix a potential deadlock when creating pcpu rt"),
free_percpu() is not called before setting non_pcpu_rt->rt6i_pcpu to NULL.
It is worth to note that rt6i_pcpu is protected by table->tb6_lock.
kmemleak somehow did not report it. We nailed it down by
observing the pcpu entries in /proc/vmallocinfo (first suggested
by Hannes, thanks!).
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Fixes: 9c7370a166 ("ipv6: Fix a potential deadlock when creating pcpu rt")
Reported-by: Petr Novopashenniy <pety@rusnet.ru>
Tested-by: Petr Novopashenniy <pety@rusnet.ru>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Petr Novopashenniy <pety@rusnet.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tables have to exist for VRFs to function. Ensure they exist
when VRF device is created.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One of our customers observed issues with FIB6 garbage collectors
running in different network namespaces blocking each other, resulting
in soft lockups (fib6_run_gc() initiated from timer runs always in
forced mode).
Now that FIB6 walkers are separated per namespace, there is no more need
for instances of fib6_run_gc() in different namespaces blocking each
other. There is still a call to icmp6_dst_gc() which operates on shared
data but this function is protected by its own shared lock.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IPv6 FIB data structures are separated per network namespace but
there is still only one global walkers list and one global walker list
lock. This means changes in one namespace unnecessarily interfere with
walkers in other namespaces.
Replace the global list with per-netns lists (and give each its own
lock).
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Global variable gc_args is only used in fib6_run_gc() and functions
called from it. As fib6_run_gc() makes sure there is at most one
instance of fib6_clean_all() running at any moment, we can replace
gc_args with a local variable which will be needed once multiple
instances (per netns) of garbage collector are allowed.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/ipv6/xfrm6_output.c
net/openvswitch/flow_netlink.c
net/openvswitch/vport-gre.c
net/openvswitch/vport-vxlan.c
net/openvswitch/vport.c
net/openvswitch/vport.h
The openvswitch conflicts were overlapping changes. One was
the egress tunnel info fix in 'net' and the other was the
vport ->send() op simplification in 'net-next'.
The xfrm6_output.c conflicts was also a simplification
overlapping a bug fix.
Signed-off-by: David S. Miller <davem@davemloft.net>
The error condition -EAGAIN, which is signaled by throw routes, tells
the rules framework to walk on searching for next matches. If the walk
ends and we stop walking the rules with the result of a throw route we
have to translate the error conditions to -ENETUNREACH.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds NLM_F_REPLACE flag to ipv6 route replace notifications.
This makes nlm_flags in ipv6 replace notifications consistent
with ipv4.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch uses a seqlock to ensure consistency between idst->dst and
idst->cookie. It also makes dst freeing from fib tree to undergo a
rcu grace period.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is a prep work to get dst freeing from fib tree undergo
a rcu grace period.
The following is a common paradigm:
if (ip6_del_rt(rt))
dst_free(rt)
which means, if rt cannot be deleted from the fib tree, dst_free(rt) now.
1. We don't know the ip6_del_rt(rt) failure is because it
was not managed by fib tree (e.g. DST_NOCACHE) or it had already been
removed from the fib tree.
2. If rt had been managed by the fib tree, ip6_del_rt(rt) failure means
dst_free(rt) has been called already. A second
dst_free(rt) is not always obviously safe. The rt may have
been destroyed already.
3. If rt is a DST_NOCACHE, dst_free(rt) should not be called.
4. It is a stopper to make dst freeing from fib tree undergo a
rcu grace period.
This patch is to use a DST_NOCACHE flag to indicate a rt is
not managed by the fib tree.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the lwtunnel state resides in per-protocol data. This is
a problem if we encapsulate ipv6 traffic in an ipv4 tunnel (or vice versa).
The xmit function of the tunnel does not know whether the packet has been
routed to it by ipv4 or ipv6, yet it needs the lwtstate data. Moving the
lwtstate data to dst_entry makes such inter-protocol tunneling possible.
As a bonus, this brings a nice diffstat.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
It saves some lines and simplify a bit the code when the state is returning
by this function. It's also useful to handle a NULL entry.
To avoid too long lines, I've also renamed lwtunnel_state_get() and
lwtunnel_state_put() to lwtstate_get() and lwtstate_put().
CC: Thomas Graf <tgraf@suug.ch>
CC: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support in ipv6 fib functions to parse Netlink
RTA encap attributes and attach encap state data to rt6_info.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After the patch
'ipv6: Only create RTF_CACHE routes after encountering pmtu exception',
we need to compensate the performance hit (bouncing dst->__refcnt).
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch creates a RTF_CACHE routes only after encountering a pmtu
exception.
After ip6_rt_update_pmtu() has inserted the RTF_CACHE route to the fib6
tree, the rt->rt6i_node->fn_sernum is bumped which will fail the
ip6_dst_check() and trigger a relookup.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
When replacing an IPv6 multipath route with "ip route replace", i.e.
NLM_F_CREATE | NLM_F_REPLACE, fib6_add_rt2node() replaces only first
matching route without fixing its siblings, resulting in corrupted
siblings linked list; removing one of the siblings can then end in an
infinite loop.
IPv6 ECMP implementation is a bit different from IPv4 so that route
replacement cannot work in exactly the same way. This should be a
reasonable approximation:
1. If the new route is ECMP-able and there is a matching ECMP-able one
already, replace it and all its siblings (if any).
2. If the new route is ECMP-able and no matching ECMP-able route exists,
replace first matching non-ECMP-able (if any) or just add the new one.
3. If the new route is not ECMP-able, replace first matching
non-ECMP-able route (if any) or add the new route.
We also need to remove the NLM_F_REPLACE flag after replacing old
route(s) by first nexthop of an ECMP route so that each subsequent
nexthop does not replace previous one.
Fixes: 51ebd31815 ("ipv6: add support of equal cost multipath (ECMP)")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x != NULL and sometimes as x. x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.
No changes detected by objdiff.
Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
arch/arm/boot/dts/imx6sx-sdb.dts
net/sched/cls_bpf.c
Two simple sets of overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Lubomir Rintel reported that during replacing a route the interface
reference counter isn't correctly decremented.
To quote bug <https://bugzilla.kernel.org/show_bug.cgi?id=91941>:
| [root@rhel7-5 lkundrak]# sh -x lal
| + ip link add dev0 type dummy
| + ip link set dev0 up
| + ip link add dev1 type dummy
| + ip link set dev1 up
| + ip addr add 2001:db8:8086::2/64 dev dev0
| + ip route add 2001:db8:8086::/48 dev dev0 proto static metric 20
| + ip route add 2001:db8:8088::/48 dev dev1 proto static metric 10
| + ip route replace 2001:db8:8086::/48 dev dev1 proto static metric 20
| + ip link del dev0 type dummy
| Message from syslogd@rhel7-5 at Jan 23 10:54:41 ...
| kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2
|
| Message from syslogd@rhel7-5 at Jan 23 10:54:51 ...
| kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2
During replacement of a rt6_info we must walk all parent nodes and check
if the to be replaced rt6_info got propagated. If so, replace it with
an alive one.
Fixes: 4a287eba2d ("IPv6 routing, NLM_F_* flag support: REPLACE and EXCL flags support, warn about missing CREATE flag")
Reported-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Tested-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.
This makes the very common pattern of
if (genlmsg_end(...) < 0) { ... }
be a whole bunch of dead code. Many places also simply do
return nlmsg_end(...);
and the caller is expected to deal with it.
This also commonly (at least for me) causes errors, because it is very
common to write
if (my_function(...))
/* error condition */
and if my_function() does "return nlmsg_end()" this is of course wrong.
Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.
Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did
- return nlmsg_end(...);
+ nlmsg_end(...);
+ return 0;
I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.
One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do the nla validation earlier, outside the write lock.
This is needed by followup patch which needs to be able to call
request_module (which can sleep) if needed.
Joint work with Daniel Borkmann.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
When IPv6 host routes with metrics attached are being added, we fetch
the metrics store from the dst via COW through dst_metrics_write_ptr(),
added through commit e5fd387ad5.
One remaining problem here is that we actually call into inet_getpeer()
and may end up allocating/creating a new peer from the kmemcache, which
may fail.
Example trace from perf probe (inet_getpeer:41) where create is 1:
ip 6877 [002] 4221.391591: probe:inet_getpeer: (ffffffff8165e293)
85e294 inet_getpeer.part.7 (<- kmem_cache_alloc())
85e578 inet_getpeer
8eb333 ipv6_cow_metrics
8f10ff fib6_commit_metrics
Therefore, a check for NULL on the return of dst_metrics_write_ptr()
is necessary here.
Joint work with Florian Westphal.
Fixes: e5fd387ad5 ("ipv6: do not overwrite inetpeer metrics prematurely")
Cc: Michal Kubeček <mkubecek@suse.cz>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Try to reduce number of possible fn_sernum mutation by constraining them
to their namespace.
Also remove rt_genid which I forgot to remove in 705f1c869d ("ipv6:
remove rt6i_genid").
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also renamed struct fib6_walker_t to fib6_walker and enum fib_walk_state_t
to fib6_walk_state as recommended by Cong Wang.
Cc: Cong Wang <cwang@twopensource.com>
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet noticed that all no-nonexthop or no-gateway routes which
are already marked DST_HOST (e.g. input routes routes) will always be
invalidated during sk_dst_check. Thus per-socket dst caching absolutely
had no effect and early demuxing had no effect.
Thus this patch removes rt6i_genid: fn_sernum already gets modified during
add operations, so we only must ensure we mutate fn_sernum during ipv6
address remove operations. This is a fairly cost extensive operations,
but address removal should not happen that often. Also our mtu update
functions do the same and we heard no complains so far. xfrm policy
changes also cause a call into fib6_flush_trees. Also plug a hole in
rt6_info (no cacheline changes).
I verified via tracing that this change has effect.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: YOSHIFUJI Hideaki <hideaki@yoshifuji.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/altera/altera_sgdma.c
net/netlink/af_netlink.c
net/sched/cls_api.c
net/sched/sch_api.c
The netlink conflict dealt with moving to netlink_capable() and
netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations
in non-init namespaces. These were simple transformations from
netlink_capable to netlink_ns_capable.
The Altera driver conflict was simply code removal overlapping some
void pointer cast cleanups in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
the parameter rt will be assigned to c.arg in function fib6_clean_tree(),
but function fib6_prune_clone() doesn't use c.arg, so we can remove it
safely.
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the ipv6 fib changes during a table dump, the walk is
restarted and the number of nodes dumped are skipped. But the existing
code doesn't advance to the next node after a node is skipped. This can
cause the dump to loop or produce lots of duplicates when the fib
is modified during the dump.
This change advances the walk to the next node if the current node is
skipped after a restart.
Signed-off-by: Kumar Sundararajan <kumar@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ERROR: "(foo*)" should be "(foo *)"
ERROR: "foo * bar" should be "foo *bar"
Suggested-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ERROR: open brace '{' following enum go on the same line
ERROR: open brace '{' following struct go on the same line
ERROR: trailing statements should be on next line
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WARNING: please, no space before tabs
WARNING: please, no spaces at the start of a line
ERROR: spaces required around that ':' (ctx:VxW)
ERROR: spaces required around that '>' (ctx:VxV)
ERROR: spaces required around that '>=' (ctx:VxV)
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an IPv6 host route with metrics exists, an attempt to add a
new route for the same target with different metrics fails but
rewrites the metrics anyway:
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 rto_min lock 1s
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1500
RTNETLINK answers: File exists
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 rto_min lock 1.5s
This is caused by all IPv6 host routes using the metrics in
their inetpeer (or the shared default). This also holds for the
new route created in ip6_route_add() which shares the metrics
with the already existing route and thus ip6_route_add()
rewrites the metrics even if the new route ends up not being
used at all.
Another problem is that old metrics in inetpeer can reappear
unexpectedly for a new route, e.g.
12sp0:~ # ip route add fec0::1 dev eth0 rto_min 1000
12sp0:~ # ip route del fec0::1
12sp0:~ # ip route add fec0::1 dev eth0
12sp0:~ # ip route change fec0::1 dev eth0 hoplimit 10
12sp0:~ # ip -6 route show
fe80::/64 dev eth0 proto kernel metric 256
fec0::1 dev eth0 metric 1024 hoplimit 10 rto_min lock 1s
Resolve the first problem by moving the setting of metrics down
into fib6_add_rt2node() to the point we are sure we are
inserting the new route into the tree. Second problem is
addressed by introducing new flag DST_METRICS_FORCE_OVERWRITE
which is set for a new host route in ip6_route_add() and makes
ipv6_cow_metrics() always overwrite the metrics in inetpeer
(even if they are not "new"); it is reset after that.
v5: use a flag in _metrics member rather than one in flags
v4: fix a typo making a condition always true (thanks to Hannes
Frederic Sowa)
v3: rewritten based on David Miller's idea to move setting the
metrics (and allocation in non-host case) down to the point we
already know the route is to be inserted. Also rebased to
net-next as it is quite late in the cycle.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
since the prune parameter for fib6_clean_all always is 0, remove it.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch provides an additional safety net against NULL
pointer dereferences while walking the fib trie for the new
/proc/net/ipv6_route walkers. I never needed it myself and am unsure
if it is needed at all, but the same checks where introduced in
2bec5a369e ("ipv6: fib: fix crash when
changing large fib while dumping it") to fix NULL pointer bugs.
This patch is separated from the first patch to make it easier to revert
if we are sure we can drop this logic.
Cc: Ben Greear <greearb@candelatech.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dumping routes on a system with lots rt6_infos in the fibs causes up to
11-order allocations in seq_file (which fail). While we could switch
there to vmalloc we could just implement the streaming interface for
/proc/net/ipv6_route. This patch switches /proc/net/ipv6_route from
single_open_net to seq_open_net.
loff_t *pos tracks dst entries.
Also kill never used struct rt6_proc_arg and now unused function
fib6_clean_all_ro.
Cc: Ben Greear <greearb@candelatech.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the kernel is compiled with CONFIG_IPV6_SUBTREES, and we return
with an error in fn = fib6_add_1(), then error codes are encoded into
the return pointer e.g. ERR_PTR(-ENOENT). In such an error case, we
write the error code into err and jump to out, hence enter the if(err)
condition. Now, if CONFIG_IPV6_SUBTREES is enabled, we check for:
if (pn != fn && pn->leaf == rt)
...
if (pn != fn && !pn->leaf && !(pn->fn_flags & RTN_RTINFO))
...
Since pn is NULL and fn is f.e. ERR_PTR(-ENOENT), then pn != fn
evaluates to true and causes a NULL-pointer dereference on further
checks on pn. Fix it, by setting both NULL in error case, so that
pn != fn already evaluates to false and no further dereference
takes place.
This was first correctly implemented in 4a287eba2 ("IPv6 routing,
NLM_F_* flag support: REPLACE and EXCL flags support, warn about
missing CREATE flag"), but the bug got later on introduced by
188c517a0 ("ipv6: return errno pointers consistently for fib6_add_1()").
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Lin Ming <mlin@ss.pku.edu.cn>
Cc: Matti Vaittinen <matti.vaittinen@nsn.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Matti Vaittinen <matti.vaittinen@nsn.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case a subtree did not match we currently stop backtracking and return
NULL (root table from fib_lookup). This could yield in invalid routing
table lookups when using subtrees.
Instead continue to backtrack until a valid subtree or node is found
and return this match.
Also remove unneeded NULL check.
Reported-by: Teco Boot <teco@inf-net.nl>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: David Lamparter <equinox@diac24.net>
Cc: <boutier@pps.univ-paris-diderot.fr>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As pointed out by Eric Dumazet, net->ipv6.ip6_rt_last_gc should
hold the last time garbage collector was run so that we should
update it whenever fib6_run_gc() calls fib6_clean_all(), not only
if we got there from ip6_dst_gc().
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
On a high-traffic router with many processors and many IPv6 dst
entries, soft lockup in fib6_run_gc() can occur when number of
entries reaches gc_thresh.
This happens because fib6_run_gc() uses fib6_gc_lock to allow
only one thread to run the garbage collector but ip6_dst_gc()
doesn't update net->ipv6.ip6_rt_last_gc until fib6_run_gc()
returns. On a system with many entries, this can take some time
so that in the meantime, other threads pass the tests in
ip6_dst_gc() (ip6_rt_last_gc is still not updated) and wait for
the lock. They then have to run the garbage collector one after
another which blocks them for quite long.
Resolve this by replacing special value ~0UL of expire parameter
to fib6_run_gc() by explicit "force" parameter to choose between
spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with
force=false if gc_thresh is reached but not max_size.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "int addrlen" in fib6_add_1 is rebundant, as we can get it from
parameter "struct in6_addr *addr" once we modified its type.
And also fix some coding style issues in fib6_add_1
Signed-off-by: Fan Du <fan.du@windriver.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Static routes in this case are non-expiring routes which did not get
configured by autoconf or by icmpv6 redirects.
To make sure we actually get an ecmp route while searching for the first
one in this fib6_node's leafs, also make sure it matches the ecmp route
assumptions.
v2:
a) Removed RTF_EXPIRE check in dst.from chain. The check of RTF_ADDRCONF
already ensures that this route, even if added again without
RTF_EXPIRES (in case of a RA announcement with infinite timeout),
does not cause the rt6i_nsiblings logic to go wrong if a later RA
updates the expiration time later.
v3:
a) Allow RTF_EXPIRES routes to enter the ecmp route set. We have to do so,
because an pmtu event could update the RTF_EXPIRES flag and we would
not count this route, if another route joins this set. We now filter
only for RTF_GATEWAY|RTF_ADDRCONF|RTF_DYNAMIC, which are flags that
don't get changed after rt6_info construction.
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>