summaryrefslogtreecommitdiff
path: root/net/ipv6/route.c
AgeCommit message (Collapse)Author
2019-05-25ipv6: prevent possible fib6 leaksEric Dumazet
[ Upstream commit 61fb0d01680771f72cc9d39783fb2c122aaad51e ] At ipv6 route dismantle, fib6_drop_pcpu_from() is responsible for finding all percpu routes and set their ->from pointer to NULL, so that fib6_ref can reach its expected value (1). The problem right now is that other cpus can still catch the route being deleted, since there is no rcu grace period between the route deletion and call to fib6_drop_pcpu_from() This can leak the fib6 and associated resources, since no notifier will take care of removing the last reference(s). I decided to add another boolean (fib6_destroying) instead of reusing/renaming exception_bucket_flushed to ease stable backports, and properly document the memory barriers used to implement this fix. This patch has been co-developped with Wei Wang. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Wei Wang <weiwan@google.com> Cc: David Ahern <dsahern@gmail.com> Cc: Martin Lau <kafai@fb.com> Acked-by: Wei Wang <weiwan@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25ipv6: fix src addr routing with the exception tableWei Wang
[ Upstream commit 510e2ceda031eed97a7a0f9aad65d271a58b460d ] When inserting route cache into the exception table, the key is generated with both src_addr and dest_addr with src addr routing. However, current logic always assumes the src_addr used to generate the key is a /128 host address. This is not true in the following scenarios: 1. When the route is a gateway route or does not have next hop. (rt6_is_gw_or_nonexthop() == false) 2. When calling ip6_rt_cache_alloc(), saddr is passed in as NULL. This means, when looking for a route cache in the exception table, we have to do the lookup twice: first time with the passed in /128 host address, second time with the src_addr stored in fib6_info. This solves the pmtu discovery issue reported by Mikael Magnusson where a route cache with a lower mtu info is created for a gateway route with src addr. However, the lookup code is not able to find this route cache. Fixes: 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache") Reported-by: Mikael Magnusson <mikael.kernel@lists.m7n.se> Bisected-by: David Ahern <dsahern@gmail.com> Signed-off-by: Wei Wang <weiwan@google.com> Cc: Martin Lau <kafai@fb.com> Cc: Eric Dumazet <edumazet@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-05ipv6: fix races in ip6_dst_destroy()Eric Dumazet
[ Upstream commit 0e2338749192ce0e52e7174c5352f627632f478a ] We had many syzbot reports that seem to be caused by use-after-free of struct fib6_info. ip6_dst_destroy(), fib6_drop_pcpu_from() and rt6_remove_exception() are writers vs rt->from, and use non consistent synchronization among themselves. Switching to xchg() will solve the issues with no possible lockdep issues. BUG: KASAN: user-memory-access in atomic_dec_and_test include/asm-generic/atomic-instrumented.h:747 [inline] BUG: KASAN: user-memory-access in fib6_info_release include/net/ip6_fib.h:294 [inline] BUG: KASAN: user-memory-access in fib6_info_release include/net/ip6_fib.h:292 [inline] BUG: KASAN: user-memory-access in fib6_drop_pcpu_from net/ipv6/ip6_fib.c:927 [inline] BUG: KASAN: user-memory-access in fib6_purge_rt+0x4f6/0x670 net/ipv6/ip6_fib.c:960 Write of size 4 at addr 0000000000ffffb4 by task syz-executor.1/7649 CPU: 0 PID: 7649 Comm: syz-executor.1 Not tainted 5.1.0-rc6+ #183 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 kasan_report.cold+0x5/0x40 mm/kasan/report.c:321 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_write+0x14/0x20 mm/kasan/common.c:108 atomic_dec_and_test include/asm-generic/atomic-instrumented.h:747 [inline] fib6_info_release include/net/ip6_fib.h:294 [inline] fib6_info_release include/net/ip6_fib.h:292 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:927 [inline] fib6_purge_rt+0x4f6/0x670 net/ipv6/ip6_fib.c:960 fib6_del_route net/ipv6/ip6_fib.c:1813 [inline] fib6_del+0xac2/0x10a0 net/ipv6/ip6_fib.c:1844 fib6_clean_node+0x3a8/0x590 net/ipv6/ip6_fib.c:2006 fib6_walk_continue+0x495/0x900 net/ipv6/ip6_fib.c:1928 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:1976 fib6_clean_tree+0xe0/0x120 net/ipv6/ip6_fib.c:2055 __fib6_clean_all+0x118/0x2a0 net/ipv6/ip6_fib.c:2071 fib6_clean_all+0x2b/0x40 net/ipv6/ip6_fib.c:2082 rt6_sync_down_dev+0x134/0x150 net/ipv6/route.c:4057 rt6_disable_ip+0x27/0x5f0 net/ipv6/route.c:4062 addrconf_ifdown+0xa2/0x1220 net/ipv6/addrconf.c:3705 addrconf_notify+0x19a/0x2260 net/ipv6/addrconf.c:3630 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1753 call_netdevice_notifiers_extack net/core/dev.c:1765 [inline] call_netdevice_notifiers net/core/dev.c:1779 [inline] dev_close_many+0x33f/0x6f0 net/core/dev.c:1522 rollback_registered_many+0x43b/0xfd0 net/core/dev.c:8177 rollback_registered+0x109/0x1d0 net/core/dev.c:8242 unregister_netdevice_queue net/core/dev.c:9289 [inline] unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9282 unregister_netdevice include/linux/netdevice.h:2658 [inline] __tun_detach+0xd5b/0x1000 drivers/net/tun.c:727 tun_detach drivers/net/tun.c:744 [inline] tun_chr_close+0xe0/0x180 drivers/net/tun.c:3443 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:876 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffeafc2a6a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001c RCX: 0000000000458da9 RDX: 0000000000412a80 RSI: 0000000000a54ef0 RDI: 0000000000000043 RBP: 00000000004be552 R08: 000000000000000c R09: 000000000004c0d1 R10: 0000000002341940 R11: 0000000000000246 R12: 00000000ffffffff R13: 00007ffeafc2a7f0 R14: 000000000004c065 R15: 00007ffeafc2a800 Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: David Ahern <dsahern@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-05ipv6: A few fixes on dereferencing rt->fromMartin KaFai Lau
[ Upstream commit 886b7a50100a50f1cbd08a6f8ec5884dfbe082dc ] It is a followup after the fix in commit 9c69a1320515 ("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: a68886a69180 ("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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27route: Avoid crash from dereferencing NULL rt->fromJonathan Lemon
[ Upstream commit 9c69a13205151c0d801de9f9d83a818e6e8f60ec ] When __ip6_rt_update_pmtu() is called, rt->from is RCU dereferenced, but is never checked for null - rt6_flush_exceptions() may have removed the entry. [ 1913.989004] RIP: 0010:ip6_rt_cache_alloc+0x13/0x170 [ 1914.209410] Call Trace: [ 1914.214798] <IRQ> [ 1914.219226] __ip6_rt_update_pmtu+0xb0/0x190 [ 1914.228649] ip6_tnl_xmit+0x2c2/0x970 [ip6_tunnel] [ 1914.239223] ? ip6_tnl_parse_tlv_enc_lim+0x32/0x1a0 [ip6_tunnel] [ 1914.252489] ? __gre6_xmit+0x148/0x530 [ip6_gre] [ 1914.262678] ip6gre_tunnel_xmit+0x17e/0x3c7 [ip6_gre] [ 1914.273831] dev_hard_start_xmit+0x8d/0x1f0 [ 1914.283061] sch_direct_xmit+0xfa/0x230 [ 1914.291521] __qdisc_run+0x154/0x4b0 [ 1914.299407] net_tx_action+0x10e/0x1f0 [ 1914.307678] __do_softirq+0xca/0x297 [ 1914.315567] irq_exit+0x96/0xa0 [ 1914.322494] smp_apic_timer_interrupt+0x68/0x130 [ 1914.332683] apic_timer_interrupt+0xf/0x20 [ 1914.341721] </IRQ> Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Reviewed-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-03ipv6: make ip6_create_rt_rcu return ip6_null_entry instead of NULLXin Long
[ Upstream commit 1c87e79a002f6a159396138cd3f3ab554a2a8887 ] 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: e873e4b9cc7e ("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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-01ipv4: Add ICMPv6 support when parse route ipprotoHangbin Liu
For ip rules, we need to use 'ipproto ipv6-icmp' to match ICMPv6 headers. But for ip -6 route, currently we only support tcp, udp and icmp. Add ICMPv6 support so we can match ipv6-icmp rules for route lookup. v2: As David Ahern and Sabrina Dubroca suggested, Add an argument to rtm_getroute_parse_ip_proto() to handle ICMP/ICMPv6 with different family. Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: eacb9384a3fe ("ipv6: support sport, dport and ip_proto in RTM_GETROUTE") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-26ipv6: Return error for RTA_VIA attributeDavid Ahern
IPv6 currently does not support nexthops outside of the AF_INET6 family. Specifically, it does not handle RTA_VIA attribute. If it is passed in a route add request, the actual route added only uses the device which is clearly not what the user intended: $ ip -6 ro add 2001:db8:2::/64 via inet 172.16.1.1 dev eth0 $ ip ro ls ... 2001:db8:2::/64 dev eth0 metric 1024 pref medium Catch this and fail the route add: $ ip -6 ro add 2001:db8:2::/64 via inet 172.16.1.1 dev eth0 Error: IPv6 does not support RTA_VIA attribute. Fixes: 03c0566542f4c ("mpls: Netlink commands to add, remove, and dump routes") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22net: Set rtm_table to RT_TABLE_COMPAT for ipv6 for tables > 255Kalash Nainwal
Set rtm_table to RT_TABLE_COMPAT for ipv6 for tables > 255 to keep legacy software happy. This is similar to what was done for ipv4 in commit 709772e6e065 ("net: Fix routing tables with id > 255 for legacy software"). Signed-off-by: Kalash Nainwal <kalash@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22ipv6: route: purge exception on removalPaolo Abeni
When a netdevice is unregistered, we flush the relevant exception via rt6_sync_down_dev() -> fib6_ifdown() -> fib6_del() -> fib6_del_route(). Finally, we end-up calling rt6_remove_exception(), where we release the relevant dst, while we keep the references to the related fib6_info and dev. Such references should be released later when the dst will be destroyed. There are a number of caches that can keep the exception around for an unlimited amount of time - namely dst_cache, possibly even socket cache. As a result device registration may hang, as demonstrated by this script: ip netns add cl ip netns add rt ip netns add srv ip netns exec rt sysctl -w net.ipv6.conf.all.forwarding=1 ip link add name cl_veth type veth peer name cl_rt_veth ip link set dev cl_veth netns cl ip -n cl link set dev cl_veth up ip -n cl addr add dev cl_veth 2001::2/64 ip -n cl route add default via 2001::1 ip -n cl link add tunv6 type ip6tnl mode ip6ip6 local 2001::2 remote 2002::1 hoplimit 64 dev cl_veth ip -n cl link set tunv6 up ip -n cl addr add 2013::2/64 dev tunv6 ip link set dev cl_rt_veth netns rt ip -n rt link set dev cl_rt_veth up ip -n rt addr add dev cl_rt_veth 2001::1/64 ip link add name rt_srv_veth type veth peer name srv_veth ip link set dev srv_veth netns srv ip -n srv link set dev srv_veth up ip -n srv addr add dev srv_veth 2002::1/64 ip -n srv route add default via 2002::2 ip -n srv link add tunv6 type ip6tnl mode ip6ip6 local 2002::1 remote 2001::2 hoplimit 64 dev srv_veth ip -n srv link set tunv6 up ip -n srv addr add 2013::1/64 dev tunv6 ip link set dev rt_srv_veth netns rt ip -n rt link set dev rt_srv_veth up ip -n rt addr add dev rt_srv_veth 2002::2/64 ip netns exec srv netserver & sleep 0.1 ip netns exec cl ping6 -c 4 2013::1 ip netns exec cl netperf -H 2013::1 -t TCP_STREAM -l 3 & sleep 1 ip -n rt link set dev rt_srv_veth mtu 1400 wait %2 ip -n cl link del cl_veth This commit addresses the issue purging all the references held by the exception at time, as we currently do for e.g. ipv6 pcpu dst entries. v1 -> v2: - re-order the code to avoid accessing dst and net after dst_dev_put() Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-21ipv6: route: enforce RCU protection in ip6_route_check_nh_onlink()Paolo Abeni
We need a RCU critical section around rt6_info->from deference, and proper annotation. Fixes: 4ed591c8ab44 ("net/ipv6: Allow onlink routes to have a device mismatch if it is the default route") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-21ipv6: route: enforce RCU protection in rt6_update_exception_stamp_rt()Paolo Abeni
We must access rt6_info->from under RCU read lock: move the dereference under such lock, with proper annotation. v1 -> v2: - avoid using multiple, racy, fetch operations for rt->from Fixes: a68886a69180 ("net/ipv6: Make from in rt6_info rcu protected") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16ipv6: route: place a warning with duplicated string with correct extackJakub Kicinski
"IPv6: " prefix is already added by pr_fmt, no need to include it again in the pr_warn() format. The message predates extack support, we can replace the whole thing with an extack message. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-02ipv6: route: Fix return value of ip6_neigh_lookup() on neigh_create() errorStefano Brivio
In ip6_neigh_lookup(), we must not return errors coming from neigh_create(): if creation of a neighbour entry fails, the lookup should return NULL, in the same way as it's done in __neigh_lookup(). Otherwise, callers legitimately checking for a non-NULL return value of the lookup function might dereference an invalid pointer. For instance, on neighbour table overflow, ndisc_router_discovery() crashes ndisc_update() by passing ERR_PTR(-ENOBUFS) as 'neigh' argument. Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: f8a1b43b709d ("net/ipv6: Create a neigh_lookup for FIB entries") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-27ipv6/route: Add a missing check on proc_dointvecAditya Pakki
While flushing the cache via ipv6_sysctl_rtcache_flush(), the call to proc_dointvec() may fail. The fix adds a check that returns the error, on failure. Signed-off-by: Aditya Pakki <pakki001@umn.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-11-18ipv6: Fix PMTU updates for UDP/raw sockets in presence of VRFDavid Ahern
Preethi reported that PMTU discovery for UDP/raw applications is not working in the presence of VRF when the socket is not bound to a device. The problem is that ip6_sk_update_pmtu does not consider the L3 domain of the skb device if the socket is not bound. Update the function to set oif to the L3 master device if relevant. Fixes: ca254490c8df ("net: Add VRF support to IPv6 stack") Reported-by: Preethi Ramachandra <preethir@juniper.net> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16ipv6: fix a dst leak when removing its exceptionXin Long
These is no need to hold dst before calling rt6_remove_exception_rt(). The call to dst_hold_safe() in ip6_link_failure() was for ip6_del_rt(), which has been removed in Commit 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes"). Otherwise, it will cause a dst leak. This patch is to simply remove the dst_hold_safe() call before calling rt6_remove_exception_rt() and also do the same in ip6_del_cached_rt(). It's safe, because the removal of the exception that holds its dst's refcnt is protected by rt6_exception_lock. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Fixes: 23fb93a4d3f1 ("net/ipv6: Cleanup exception and cache route handling") Reported-by: Li Shuang <shuali@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-06net: Add extack argument to ip_fib_metrics_initDavid Ahern
Add extack argument to ip_fib_metrics_init and add messages for invalid metrics. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-24net/ipv6: Allow onlink routes to have a device mismatch if it is the default ↵David Ahern
route The intent of ip6_route_check_nh_onlink is to make sure the gateway given for an onlink route is not actually on a connected route for a different interface (e.g., 2001:db8:1::/64 is on dev eth1 and then an onlink route has a via 2001:db8:1::1 dev eth2). If the gateway lookup hits the default route then it most likely will be a different interface than the onlink route which is ok. Update ip6_route_check_nh_onlink to disregard the device mismatch if the gateway lookup hits the default route. Turns out the existing onlink tests are passing because there is no default route or it is an unreachable default, so update the onlink tests to have a default route other than unreachable. Fixes: fc1e64e1092f6 ("net/ipv6: Add support for onlink flag") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
net/sched/cls_api.c has overlapping changes to a call to nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL to the 5th argument, and another (from 'net-next') added cb->extack instead of NULL to the 6th argument. net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to code which moved (to mr_table_dump)) in 'net-next'. Thanks to David Ahern for the heads up. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16net/ipv6: Plumb support for filtering route dumpsDavid Ahern
Implement kernel side filtering of routes by table id, egress device index, protocol, and route type. If the table id is given in the filter, lookup the table and call fib6_dump_table directly for it. Move the existing route flags check for prefix only routes to the new filter. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15ipv6: rate-limit probes for neighbourless routesSabrina Dubroca
When commit 270972554c91 ("[IPV6]: ROUTE: Add Router Reachability Probing (RFC4191).") introduced router probing, the rt6_probe() function required that a neighbour entry existed. This neighbour entry is used to record the timestamp of the last probe via the ->updated field. Later, commit 2152caea7196 ("ipv6: Do not depend on rt->n in rt6_probe().") removed the requirement for a neighbour entry. Neighbourless routes skip the interval check and are not rate-limited. This patch adds rate-limiting for neighbourless routes, by recording the timestamp of the last probe in the fib6_info itself. Fixes: 2152caea7196 ("ipv6: Do not depend on rt->n in rt6_probe().") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12net/ipv6: Add knob to skip DELROUTE message on device downDavid Ahern
Another difference between IPv4 and IPv6 is the generation of RTM_DELROUTE notifications when a device is taken down (admin down) or deleted. IPv4 does not generate a message for routes evicted by the down or delete; IPv6 does. A NOS at scale really needs to avoid these messages and have IPv4 and IPv6 behave similarly, relying on userspace to handle link notifications and evict the routes. At this point existing user behavior needs to be preserved. Since notifications are a global action (not per app) the only way to preserve existing behavior and allow the messages to be skipped is to add a new sysctl (net/ipv6/route/skip_notify_on_dev_down) which can be set to disable the notificatioons. IPv6 route code already supports the option to skip the message (it is used for multipath routes for example). Besides the new sysctl we need to pass the skip_notify setting through the generic fib6_clean and fib6_walk functions to fib6_clean_node and to set skip_notify on calls to __ip_del_rt for the addrconf_ifdown path. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10net/ipv6: Make ipv6_route_table_template staticDavid Ahern
ipv6_route_table_template is exported but there are no users outside of route.c. Make it static. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08net: Add extack to nlmsg_parseDavid Ahern
Make sure extack is passed to nlmsg_parse where easy to do so. Most of these are dump handlers and leveraging the extack in the netlink_callback. Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Christian Brauner <christian@brauner.io> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05ipv6: do not leave garbage in rt->fib6_metricsEric Dumazet
In case ip_fib_metrics_init() returns an error, we better rewrite rt->fib6_metrics with &dst_default_metrics so that we do not crash later in ip_fib_metrics_put() Fixes: 767a2217533f ("net: common metrics init helper for FIB entries") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-04net: Move free of dst_metrics to helperDavid Ahern
Move the refcounting and potential free of dst metrics associated for ipv4 and ipv6 to a common helper. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-04net: common metrics init helper for dst_entryDavid Ahern
ipv4 and ipv6 both use refcounted metrics if FIB entries have metrics set. Move the common initialization code to a helper and use for both protocols. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-04net: common metrics init helper for FIB entriesDavid Ahern
Consolidate initialization of ipv4 and ipv6 metrics when fib entries are created into a single helper, ip_fib_metrics_init, that handles the call to ip_metrics_convert. If no metrics are defined for the fib entry, then the metrics is set to dst_default_metrics. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net' overlapped the renaming of a netlink attribute in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: inet6_rtm_getroute() - use new style struct initializer instead of memsetMaciej Żenczykowski
Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: rtm_to_fib6_config() - use new style struct initializer instead of memsetMaciej Żenczykowski
(allows for better compiler optimization) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: rtmsg_to_fib6_config() - use new style struct initializer instead of memsetMaciej Żenczykowski
(allows for better compiler optimization) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: ip6_update_pmtu() - use new style struct initializer instead of memsetMaciej Żenczykowski
(allows for better compiler optimization) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: remove 1 always zero parameter from ip6_redirect_no_header()Maciej Żenczykowski
(the parameter in question is mark) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: ip6_redirect_no_header() - use new style struct initializer instead of ↵Maciej Żenczykowski
memset (allows for better compiler optimization) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: ip6_redirect() - use new style struct initializer instead of memsetMaciej Żenczykowski
(allows for better compiler optimization) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26net/ipv6: Remove extra call to ip6_convert_metrics for multipath caseDavid Ahern
The change to move metrics from the dst to rt6_info moved the call to ip6_convert_metrics from ip6_route_add to ip6_route_info_create. In doing so it makes the call in ip6_route_info_append redundant and actually leaks the metrics installed as part of the ip6_route_info_create. Remove the now unnecessary call. Fixes: d4ead6b34b67f ("net/ipv6: move metrics from dst to rt6_info") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Version bump conflict in batman-adv, take what's in net-next. iavf conflict, adjustment of netdev_ops in net-next conflicting with poll controller method removal in net. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-19ipv6: Allow the l3mdev to be a loopbackRobert Shearman
There is no way currently for an IPv6 client connect using a loopback address in a VRF, whereas for IPv4 the loopback address can be added: $ sudo ip addr add dev vrfred 127.0.0.1/8 $ sudo ip -6 addr add ::1/128 dev vrfred RTNETLINK answers: Cannot assign requested address So allow ::1 to be configured on an L3 master device. In order for this to be usable ip_route_output_flags needs to not consider ::1 to be a link scope address (since oif == l3mdev and so it would be dropped), and ipv6_rcv needs to consider the l3mdev to be a loopback device so that it doesn't drop the packets. Signed-off-by: Robert Shearman <rshearma@vyatta.att-mail.com> Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-18ipv6: fix memory leak on dst->_metricsWei Wang
When dst->_metrics and f6i->fib6_metrics share the same memory, both take reference count on the dst_metrics structure. However, when dst is destroyed, ip6_dst_destroy() only invokes dst_destroy_metrics_generic() which does not take care of READONLY metrics and does not release refcnt. This causes memory leak. Similar to ipv4 logic, the fix is to properly release refcnt and free the memory space pointed by dst->_metrics if refcnt becomes 0. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-18Revert "ipv6: fix double refcount of fib6_metrics"Wei Wang
This reverts commit e70a3aad44cc8b24986687ffc98c4a4f6ecf25ea. This change causes use-after-free on dst->_metrics. The crash trace looks like this: [ 97.763269] BUG: KASAN: use-after-free in ip6_mtu+0x116/0x140 [ 97.769038] Read of size 4 at addr ffff881781d2cf84 by task svw_NetThreadEv/8801 [ 97.777954] CPU: 76 PID: 8801 Comm: svw_NetThreadEv Not tainted 4.15.0-smp-DEV #11 [ 97.777956] Hardware name: Default string Default string/Indus_QC_02, BIOS 5.46.4 03/29/2018 [ 97.777957] Call Trace: [ 97.777971] [<ffffffff895709db>] dump_stack+0x4d/0x72 [ 97.777985] [<ffffffff881651df>] print_address_description+0x6f/0x260 [ 97.777997] [<ffffffff88165747>] kasan_report+0x257/0x370 [ 97.778001] [<ffffffff894488e6>] ? ip6_mtu+0x116/0x140 [ 97.778004] [<ffffffff881658b9>] __asan_report_load4_noabort+0x19/0x20 [ 97.778008] [<ffffffff894488e6>] ip6_mtu+0x116/0x140 [ 97.778013] [<ffffffff892bb91e>] tcp_current_mss+0x12e/0x280 [ 97.778016] [<ffffffff892bb7f0>] ? tcp_mtu_to_mss+0x2d0/0x2d0 [ 97.778022] [<ffffffff887b45b8>] ? depot_save_stack+0x138/0x4a0 [ 97.778037] [<ffffffff87c38985>] ? __mmdrop+0x145/0x1f0 [ 97.778040] [<ffffffff881643b1>] ? save_stack+0xb1/0xd0 [ 97.778046] [<ffffffff89264c82>] tcp_send_mss+0x22/0x220 [ 97.778059] [<ffffffff89273a49>] tcp_sendmsg_locked+0x4f9/0x39f0 [ 97.778062] [<ffffffff881642b4>] ? kasan_check_write+0x14/0x20 [ 97.778066] [<ffffffff89273550>] ? tcp_sendpage+0x60/0x60 [ 97.778070] [<ffffffff881cb359>] ? rw_copy_check_uvector+0x69/0x280 [ 97.778075] [<ffffffff8873c65f>] ? import_iovec+0x9f/0x430 [ 97.778078] [<ffffffff88164be7>] ? kasan_slab_free+0x87/0xc0 [ 97.778082] [<ffffffff8873c5c0>] ? memzero_page+0x140/0x140 [ 97.778085] [<ffffffff881642b4>] ? kasan_check_write+0x14/0x20 [ 97.778088] [<ffffffff89276f6c>] tcp_sendmsg+0x2c/0x50 [ 97.778092] [<ffffffff89276f6c>] ? tcp_sendmsg+0x2c/0x50 [ 97.778098] [<ffffffff89352d43>] inet_sendmsg+0x103/0x480 [ 97.778102] [<ffffffff89352c40>] ? inet_gso_segment+0x15b0/0x15b0 [ 97.778105] [<ffffffff890294da>] sock_sendmsg+0xba/0xf0 [ 97.778108] [<ffffffff8902ab6a>] ___sys_sendmsg+0x6ca/0x8e0 [ 97.778113] [<ffffffff87dccac1>] ? hrtimer_try_to_cancel+0x71/0x3b0 [ 97.778116] [<ffffffff8902a4a0>] ? copy_msghdr_from_user+0x3d0/0x3d0 [ 97.778119] [<ffffffff881646d1>] ? memset+0x31/0x40 [ 97.778123] [<ffffffff87a0cff5>] ? schedule_hrtimeout_range_clock+0x165/0x380 [ 97.778127] [<ffffffff87a0ce90>] ? hrtimer_nanosleep_restart+0x250/0x250 [ 97.778130] [<ffffffff87dcc700>] ? __hrtimer_init+0x180/0x180 [ 97.778133] [<ffffffff87dd1f82>] ? ktime_get_ts64+0x172/0x200 [ 97.778137] [<ffffffff8822b8ec>] ? __fget_light+0x8c/0x2f0 [ 97.778141] [<ffffffff8902d5c6>] __sys_sendmsg+0xe6/0x190 [ 97.778144] [<ffffffff8902d5c6>] ? __sys_sendmsg+0xe6/0x190 [ 97.778147] [<ffffffff8902d4e0>] ? SyS_shutdown+0x20/0x20 [ 97.778152] [<ffffffff87cd4370>] ? wake_up_q+0xe0/0xe0 [ 97.778155] [<ffffffff8902d670>] ? __sys_sendmsg+0x190/0x190 [ 97.778158] [<ffffffff8902d683>] SyS_sendmsg+0x13/0x20 [ 97.778162] [<ffffffff87a1600c>] do_syscall_64+0x2ac/0x430 [ 97.778166] [<ffffffff87c17515>] ? do_page_fault+0x35/0x3d0 [ 97.778171] [<ffffffff8960131f>] ? page_fault+0x2f/0x50 [ 97.778174] [<ffffffff89600071>] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [ 97.778177] RIP: 0033:0x7f83fa36000d [ 97.778178] RSP: 002b:00007f83ef9229e0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e [ 97.778180] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f83fa36000d [ 97.778182] RDX: 0000000000004000 RSI: 00007f83ef922f00 RDI: 0000000000000036 [ 97.778183] RBP: 00007f83ef923040 R08: 00007f83ef9231f8 R09: 00007f83ef923168 [ 97.778184] R10: 0000000000000000 R11: 0000000000000293 R12: 00007f83f69c5b40 [ 97.778185] R13: 000000000000001c R14: 0000000000000001 R15: 0000000000004000 [ 97.779684] Allocated by task 5919: [ 97.783185] save_stack+0x46/0xd0 [ 97.783187] kasan_kmalloc+0xad/0xe0 [ 97.783189] kmem_cache_alloc_trace+0xdf/0x580 [ 97.783190] ip6_convert_metrics.isra.79+0x7e/0x190 [ 97.783192] ip6_route_info_create+0x60a/0x2480 [ 97.783193] ip6_route_add+0x1d/0x80 [ 97.783195] inet6_rtm_newroute+0xdd/0xf0 [ 97.783198] rtnetlink_rcv_msg+0x641/0xb10 [ 97.783200] netlink_rcv_skb+0x27b/0x3e0 [ 97.783202] rtnetlink_rcv+0x15/0x20 [ 97.783203] netlink_unicast+0x4be/0x720 [ 97.783204] netlink_sendmsg+0x7bc/0xbf0 [ 97.783205] sock_sendmsg+0xba/0xf0 [ 97.783207] ___sys_sendmsg+0x6ca/0x8e0 [ 97.783208] __sys_sendmsg+0xe6/0x190 [ 97.783209] SyS_sendmsg+0x13/0x20 [ 97.783211] do_syscall_64+0x2ac/0x430 [ 97.783213] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 [ 97.784709] Freed by task 0: [ 97.785056] knetbase: Error: /proc/sys/net/core/txcs_enable does not exist [ 97.794497] save_stack+0x46/0xd0 [ 97.794499] kasan_slab_free+0x71/0xc0 [ 97.794500] kfree+0x7c/0xf0 [ 97.794501] fib6_info_destroy_rcu+0x24f/0x310 [ 97.794504] rcu_process_callbacks+0x38b/0x1730 [ 97.794506] __do_softirq+0x1c8/0x5d0 Reported-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-18Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Two new tls tests added in parallel in both net and net-next. Used Stephen Rothwell's linux-next resolution. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17net/ipv6: do not copy dst flags on rt initPeter Oskolkov
DST_NOCOUNT in dst_entry::flags tracks whether the entry counts toward route cache size (net->ipv6.sysctl.ip6_rt_max_size). If the flag is NOT set, dst_ops::pcpuc_entries counter is incremented in dist_init() and decremented in dst_destroy(). This flag is tied to allocation/deallocation of dst_entry and should not be copied from another dst/route. Otherwise it can happen that dst_ops::pcpuc_entries counter grows until no new routes can be allocated because the counter reached ip6_rt_max_size due to DST_NOCOUNT not set and thus no counter decrements on gc-ed routes. Fixes: 3b6761d18bc1 ("net/ipv6: Move dst flags to booleans in fib entries") Cc: David Ahern <dsahern@gmail.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: Peter Oskolkov <posk@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-13ipv6: use rt6_info members when dst is set in rt6_fill_nodeXin Long
In inet6_rtm_getroute, since Commit 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes"), it has used rt->from to dump route info instead of rt. However for some route like cache, some of its information like flags or gateway is not the same as that of the 'from' one. It caused 'ip route get' to dump the wrong route information. In Jianlin's testing, the output information even lost the expiration time for a pmtu route cache due to the wrong fib6_flags. So change to use rt6_info members for dst addr, src addr, flags and gateway when it tries to dump a route entry without fibmatch set. v1->v2: - not use rt6i_prefsrc. - also fix the gw dump issue. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-10net/ipv6: Remove rt6i_prefsrcDavid Ahern
After the conversion to fib6_info, rt6i_prefsrc has a single user that reads the value and otherwise it is only set. The one reader can be converted to use rt->from so rt6i_prefsrc can be removed, reducing rt6_info by another 20 bytes. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-09-01ipv6: don't get lwtstate twice in ip6_rt_copy_init()Alexey Kodanev
Commit 80f1a0f4e0cd ("net/ipv6: Put lwtstate when destroying fib6_info") partially fixed the kmemleak [1], lwtstate can be copied from fib6_info, with ip6_rt_copy_init(), and it should be done only once there. rt->dst.lwtstate is set by ip6_rt_init_dst(), at the start of the function ip6_rt_copy_init(), so there is no need to get it again at the end. With this patch, lwtstate also isn't copied from RTF_REJECT routes. [1]: unreferenced object 0xffff880b6aaa14e0 (size 64): comm "ip", pid 10577, jiffies 4295149341 (age 1273.903s) hex dump (first 32 bytes): 01 00 04 00 04 00 00 00 10 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<0000000018664623>] lwtunnel_build_state+0x1bc/0x420 [<00000000b73aa29a>] ip6_route_info_create+0x9f7/0x1fd0 [<00000000ee2c5d1f>] ip6_route_add+0x14/0x70 [<000000008537b55c>] inet6_rtm_newroute+0xd9/0xe0 [<000000002acc50f5>] rtnetlink_rcv_msg+0x66f/0x8e0 [<000000008d9cd381>] netlink_rcv_skb+0x268/0x3b0 [<000000004c893c76>] netlink_unicast+0x417/0x5a0 [<00000000f2ab1afb>] netlink_sendmsg+0x70b/0xc30 [<00000000890ff0aa>] sock_sendmsg+0xb1/0xf0 [<00000000a2e7b66f>] ___sys_sendmsg+0x659/0x950 [<000000001e7426c8>] __sys_sendmsg+0xde/0x170 [<00000000fe411443>] do_syscall_64+0x9f/0x4a0 [<000000001be7b28b>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<000000006d21f353>] 0xffffffffffffffff Fixes: 6edb3c96a5f0 ("net/ipv6: Defer initialization of dst to data path") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-31net/ipv6: Do not reset nl_net in ip6_route_info_createDavid Ahern
nl_net is set on entry to ip6_route_info_create. Only devices within that namespace are considered so no need to reset it before returning. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>