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2017-06-08ila_xlat: add missing hash secret initializationArnd Bergmann
While discussing the possible merits of clang warning about unused initialized functions, I found one function that was clearly meant to be called but never actually is. __ila_hash_secret_init() initializes the hash value for the ila locator, apparently this is intended to prevent hash collision attacks, but this ends up being a read-only zero constant since there is no caller. I could find no indication of why it was never called, the earliest patch submission for the module already was like this. If my interpretation is right, we certainly want to backport the patch to stable kernels as well. I considered adding it to the ila_xlat_init callback, but for best effect the random data is read as late as possible, just before it is first used. The underlying net_get_random_once() is already highly optimized to avoid overhead when called frequently. Fixes: 7f00feaf1076 ("ila: Add generic ILA translation facility") Cc: stable@vger.kernel.org Link: https://www.spinics.net/lists/kernel/msg2527243.html Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08tcp: add TCPMemoryPressuresChrono counterEric Dumazet
DRAM supply shortage and poor memory pressure tracking in TCP stack makes any change in SO_SNDBUF/SO_RCVBUF (or equivalent autotuning limits) and tcp_mem[] quite hazardous. TCPMemoryPressures SNMP counter is an indication of tcp_mem sysctl limits being hit, but only tracking number of transitions. If TCP stack behavior under stress was perfect : 1) It would maintain memory usage close to the limit. 2) Memory pressure state would be entered for short times. We certainly prefer 100 events lasting 10ms compared to one event lasting 200 seconds. This patch adds a new SNMP counter tracking cumulative duration of memory pressure events, given in ms units. $ cat /proc/sys/net/ipv4/tcp_mem 3088 4117 6176 $ grep TCP /proc/net/sockstat TCP: inuse 180 orphan 0 tw 2 alloc 234 mem 4140 $ nstat -n ; sleep 10 ; nstat |grep Pressure TcpExtTCPMemoryPressures 1700 TcpExtTCPMemoryPressuresChrono 5209 v2: Used EXPORT_SYMBOL_GPL() instead of EXPORT_SYMBOL() as David instructed. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08net: ipv6: Release route when device is unregisteringDavid Ahern
Roopa reported attempts to delete a bond device that is referenced in a multipath route is hanging: $ ifdown bond2 # ifupdown2 command that deletes virtual devices unregister_netdevice: waiting for bond2 to become free. Usage count = 2 Steps to reproduce: echo 1 > /proc/sys/net/ipv6/conf/all/ignore_routes_with_linkdown ip link add dev bond12 type bond ip link add dev bond13 type bond ip addr add 2001:db8:2::0/64 dev bond12 ip addr add 2001:db8:3::0/64 dev bond13 ip route add 2001:db8:33::0/64 nexthop via 2001:db8:2::2 nexthop via 2001:db8:3::2 ip link del dev bond12 ip link del dev bond13 The root cause is the recent change to keep routes on a linkdown. Update the check to detect when the device is unregistering and release the route for that case. Fixes: a1a22c12060e4 ("net: ipv6: Keep nexthop of multipath route on admin down") Reported-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08tcp: Namespaceify sysctl_tcp_timestampsEric Dumazet
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08tcp: Namespaceify sysctl_tcp_sackEric Dumazet
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-08tcp: add a struct net parameter to tcp_parse_options()Eric Dumazet
We want to move some TCP sysctls to net namespaces in the future. tcp_window_scaling, tcp_sack and tcp_timestamps being fetched from tcp_parse_options(), we need to pass an extra parameter. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-07net: Fix inconsistent teardown and release of private netdev state.David S. Miller
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>
2017-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Just some simple overlapping changes in marvell PHY driver and the DSA core code. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06net/ipv6: Fix CALIPSO causing GPF with datagram supportRichard Haines
When using CALIPSO with IPPROTO_UDP it is possible to trigger a GPF as the IP header may have moved. Also update the payload length after adding the CALIPSO option. Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Huw Davies <huw@codeweavers.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06Revert "sit: reload iphdr in ipip6_rcv"David S. Miller
This reverts commit b699d0035836f6712917a41e7ae58d84359b8ff9. As per Eric Dumazet, the pskb_may_pull() is a NOP in this particular case, so the 'iph' reload is unnecessary. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04sit: reload iphdr in ipip6_rcvHaishuang Yan
Since iptunnel_pull_header() can call pskb_may_pull(), we must reload any pointer that was related to skb->head. Fixes: a09a4c8dd1ec ("tunnels: Remove encapsulation offloads on decap") Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04ipsec: check return value of skb_to_sgvec alwaysJason A. Donenfeld
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04net: ping: do not abuse udp_poll()Eric Dumazet
Alexander reported various KASAN messages triggered in recent kernels The problem is that ping sockets should not use udp_poll() in the first place, and recent changes in UDP stack finally exposed this old bug. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Sasha Levin <alexander.levin@verizon.com> Cc: Solar Designer <solar@openwall.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Lorenzo Colitti <lorenzo@google.com> Acked-By: Lorenzo Colitti <lorenzo@google.com> Tested-By: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04ipv6: Fix leak in ipv6_gso_segment().David S. Miller
If ip6_find_1stfragopt() fails and we return an error we have to free up 'segs' because nobody else is going to. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-04ip6_tunnel: fix traffic class routing for tunnelsLiam McBirnie
ip6_route_output() requires that the flowlabel contains the traffic class for policy routing. Commit 0e9a709560db ("ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets") removed the code which previously added the traffic class to the flowlabel. The traffic class is added here because only route lookup needs the flowlabel to contain the traffic class. Fixes: 0e9a709560db ("ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets") Signed-off-by: Liam McBirnie <liam.mcbirnie@boeing.com> Acked-by: Peter Dawson <peter.a.dawson@boeing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-02ipv6: xfrm: Handle errors reported by xfrm6_find_1stfragopt()Ben Hutchings
xfrm6_find_1stfragopt() may now return an error code and we must not treat it as a length. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Acked-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30net: add extack arg to lwtunnel build stateDavid Ahern
Pass extack arg down to lwtunnel_build_state and the build_state callbacks. Add messages for failures in lwtunnel_build_state, and add the extarg to nla_parse where possible in the build_state callbacks. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-30net: lwtunnel: Add extack to encap attr validationDavid Ahern
Pass extack down to lwtunnel_valid_encap_type and lwtunnel_valid_encap_type_attr. Add messages for unknown or unsupported encap types. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-29netfilter: conntrack: rename nf_ct_iterate_cleanupFlorian Westphal
There are several places where we needlesly call nf_ct_iterate_cleanup, we should instead iterate the full table at module unload time. This is a leftover from back when the conntrack table got duplicated per net namespace. So rename nf_ct_iterate_cleanup to nf_ct_iterate_cleanup_net. A later patch will then add a non-net variant. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Overlapping changes in drivers/net/phy/marvell.c, bug fix in 'net' restricting a HW workaround alongside cleanups in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packetsPeter Dawson
This fix addresses two problems in the way the DSCP field is formulated on the encapsulating header of IPv6 tunnels. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195661 1) The IPv6 tunneling code was manipulating the DSCP field of the encapsulating packet using the 32b flowlabel. Since the flowlabel is only the lower 20b it was incorrect to assume that the upper 12b containing the DSCP and ECN fields would remain intact when formulating the encapsulating header. This fix handles the 'inherit' and 'fixed-value' DSCP cases explicitly using the extant dsfield u8 variable. 2) The use of INET_ECN_encapsulate(0, dsfield) in ip6_tnl_xmit was incorrect and resulted in the DSCP value always being set to 0. Commit 90427ef5d2a4 ("ipv6: fix flow labels when the traffic class is non-0") caused the regression by masking out the flowlabel which exposed the incorrect handling of the DSCP portion of the flowlabel in ip6_tunnel and ip6_gre. Fixes: 90427ef5d2a4 ("ipv6: fix flow labels when the traffic class is non-0") Signed-off-by: Peter Dawson <peter.a.dawson@boeing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-26net: ipv6: RTM_GETROUTE: return matched fib result when requestedRoopa Prabhu
This patch adds support to return matched fib result when RTM_F_FIB_MATCH flag is specified in RTM_GETROUTE request. This is useful for user-space applications/controllers wanting to query a matching route. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-05-22net: ipv6: Add extack messages for route add failuresDavid Ahern
Add messages for non-obvious errors (e.g, no need to add text for malloc failures or ENODEV failures). This mostly covers the annoying EINVAL errors Some message strings violate the 80-columns but searchable strings need to trump that rule. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22net: ipv6: Plumb extack through route add functionsDavid Ahern
Plumb extack argument down to route add functions. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22ipv6: fix out of bound writes in __ip6_append_data()Eric Dumazet
Andrey Konovalov and idaifish@gmail.com reported crashes caused by one skb shared_info being overwritten from __ip6_append_data() Andrey program lead to following state : copy -4200 datalen 2000 fraglen 2040 maxfraglen 2040 alloclen 2048 transhdrlen 0 offset 0 fraggap 6200 The skb_copy_and_csum_bits(skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); is overwriting skb->head and skb_shared_info Since we apparently detect this rare condition too late, move the code earlier to even avoid allocating skb and risking crashes. Once again, many thanks to Andrey and syzkaller team. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reported-by: <idaifish@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-22ipv6: remove unused variables in esp6Stephen Hemminger
Resolves warnings: net/ipv6/esp6.c: In function ‘esp_ssg_unref’: net/ipv6/esp6.c:121:10: warning: variable ‘seqhi’ set but not used [-Wunused-but-set-variable] net/ipv6/esp6.c: In function ‘esp6_output_head’: net/ipv6/esp6.c:227:21: warning: variable ‘esph’ set but not used [-Wunused-but-set-variable] Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-05-21ipv6: drop unused variables in seg6_genl_dumphacstephen hemminger
THe seg6_pernet_data variable was set but never used. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-21fou: make local function staticstephen hemminger
The build header functions are not used by any other code. net/ipv6/fou6.c:36:5: warning: no previous prototype for ‘fou6_build_header’ [-Wmissing-prototypes] net/ipv6/fou6.c:54:5: warning: no previous prototype for ‘gue6_build_header’ [-Wmissing-prototypes] Need to do some code rearranging to satisfy different Kconfig possiblities. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-21ila: propagate error code in ila_outputstephen hemminger
This warning: net/ipv6/ila/ila_lwt.c: In function ‘ila_output’: net/ipv6/ila/ila_lwt.c:42:6: warning: variable ‘err’ set but not used [-Wunused-but-set-variable] It looks like the code attempts to set propagate different error values, but always returned -EINVAL. Compile tested only. Needs review by original author. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-19sk_buff: remove support for csum_bad in sk_buffDavide Caratti
This bit was introduced with commit 5a21232983aa ("net: Support for csum_bad in skbuff") to reduce the stack workload when processing RX packets carrying a wrong Internet Checksum. Up to now, only one driver and GRO core are setting it. Suggested-by: Tom Herbert <tom@herbertland.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-19ah: use crypto_memneq to check the ICVSabrina Dubroca
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-05-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-05-18udp: make *udp*_queue_rcv_skb() functions staticPaolo Abeni
Since the udp memory accounting refactor, we don't need any more to export the *udp*_queue_rcv_skb(). Make them static and fix a couple of sparse warnings: net/ipv4/udp.c:1615:5: warning: symbol 'udp_queue_rcv_skb' was not declared. Should it be static? net/ipv6/udp.c:572:5: warning: symbol 'udpv6_queue_rcv_skb' was not declared. Should it be static? Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema") Fixes: c915fe13cbaa ("udplite: fix NULL pointer dereference") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17ipv6: Check ip6_find_1stfragopt() return value properly.David S. Miller
Do not use unsigned variables to see if it returns a negative error or not. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17tcp: switch TCP TS option (RFC 7323) to 1ms clockEric Dumazet
TCP Timestamps option is defined in RFC 7323 Traditionally on linux, it has been tied to the internal 'jiffies' variable, because it had been a cheap and good enough generator. For TCP flows on the Internet, 1 ms resolution would be much better than 4ms or 10ms (HZ=250 or HZ=100 respectively) For TCP flows in the DC, Google has used usec resolution for more than two years with great success [1] Receive size autotuning (DRS) is indeed more precise and converges faster to optimal window size. This patch converts tp->tcp_mstamp to a plain u64 value storing a 1 usec TCP clock. This choice will allow us to upstream the 1 usec TS option as discussed in IETF 97. [1] https://www.ietf.org/proceedings/97/slides/slides-97-tcpm-tcp-options-for-low-latency-00.pdf Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-17ipv6: Prevent overrun when parsing v6 header optionsCraig Gallek
The KASAN warning repoted below was discovered with a syzkaller program. The reproducer is basically: int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP); send(s, &one_byte_of_data, 1, MSG_MORE); send(s, &more_than_mtu_bytes_data, 2000, 0); The socket() call sets the nexthdr field of the v6 header to NEXTHDR_HOP, the first send call primes the payload with a non zero byte of data, and the second send call triggers the fragmentation path. The fragmentation code tries to parse the header options in order to figure out where to insert the fragment option. Since nexthdr points to an invalid option, the calculation of the size of the network header can made to be much larger than the linear section of the skb and data is read outside of it. This fix makes ip6_find_1stfrag return an error if it detects running out-of-bounds. [ 42.361487] ================================================================== [ 42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730 [ 42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789 [ 42.366469] [ 42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41 [ 42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 [ 42.368824] Call Trace: [ 42.369183] dump_stack+0xb3/0x10b [ 42.369664] print_address_description+0x73/0x290 [ 42.370325] kasan_report+0x252/0x370 [ 42.370839] ? ip6_fragment+0x11c8/0x3730 [ 42.371396] check_memory_region+0x13c/0x1a0 [ 42.371978] memcpy+0x23/0x50 [ 42.372395] ip6_fragment+0x11c8/0x3730 [ 42.372920] ? nf_ct_expect_unregister_notifier+0x110/0x110 [ 42.373681] ? ip6_copy_metadata+0x7f0/0x7f0 [ 42.374263] ? ip6_forward+0x2e30/0x2e30 [ 42.374803] ip6_finish_output+0x584/0x990 [ 42.375350] ip6_output+0x1b7/0x690 [ 42.375836] ? ip6_finish_output+0x990/0x990 [ 42.376411] ? ip6_fragment+0x3730/0x3730 [ 42.376968] ip6_local_out+0x95/0x160 [ 42.377471] ip6_send_skb+0xa1/0x330 [ 42.377969] ip6_push_pending_frames+0xb3/0xe0 [ 42.378589] rawv6_sendmsg+0x2051/0x2db0 [ 42.379129] ? rawv6_bind+0x8b0/0x8b0 [ 42.379633] ? _copy_from_user+0x84/0xe0 [ 42.380193] ? debug_check_no_locks_freed+0x290/0x290 [ 42.380878] ? ___sys_sendmsg+0x162/0x930 [ 42.381427] ? rcu_read_lock_sched_held+0xa3/0x120 [ 42.382074] ? sock_has_perm+0x1f6/0x290 [ 42.382614] ? ___sys_sendmsg+0x167/0x930 [ 42.383173] ? lock_downgrade+0x660/0x660 [ 42.383727] inet_sendmsg+0x123/0x500 [ 42.384226] ? inet_sendmsg+0x123/0x500 [ 42.384748] ? inet_recvmsg+0x540/0x540 [ 42.385263] sock_sendmsg+0xca/0x110 [ 42.385758] SYSC_sendto+0x217/0x380 [ 42.386249] ? SYSC_connect+0x310/0x310 [ 42.386783] ? __might_fault+0x110/0x1d0 [ 42.387324] ? lock_downgrade+0x660/0x660 [ 42.387880] ? __fget_light+0xa1/0x1f0 [ 42.388403] ? __fdget+0x18/0x20 [ 42.388851] ? sock_common_setsockopt+0x95/0xd0 [ 42.389472] ? SyS_setsockopt+0x17f/0x260 [ 42.390021] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 42.390650] SyS_sendto+0x40/0x50 [ 42.391103] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.391731] RIP: 0033:0x7fbbb711e383 [ 42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383 [ 42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003 [ 42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018 [ 42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad [ 42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00 [ 42.397257] [ 42.397411] Allocated by task 3789: [ 42.397702] save_stack_trace+0x16/0x20 [ 42.398005] save_stack+0x46/0xd0 [ 42.398267] kasan_kmalloc+0xad/0xe0 [ 42.398548] kasan_slab_alloc+0x12/0x20 [ 42.398848] __kmalloc_node_track_caller+0xcb/0x380 [ 42.399224] __kmalloc_reserve.isra.32+0x41/0xe0 [ 42.399654] __alloc_skb+0xf8/0x580 [ 42.400003] sock_wmalloc+0xab/0xf0 [ 42.400346] __ip6_append_data.isra.41+0x2472/0x33d0 [ 42.400813] ip6_append_data+0x1a8/0x2f0 [ 42.401122] rawv6_sendmsg+0x11ee/0x2db0 [ 42.401505] inet_sendmsg+0x123/0x500 [ 42.401860] sock_sendmsg+0xca/0x110 [ 42.402209] ___sys_sendmsg+0x7cb/0x930 [ 42.402582] __sys_sendmsg+0xd9/0x190 [ 42.402941] SyS_sendmsg+0x2d/0x50 [ 42.403273] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.403718] [ 42.403871] Freed by task 1794: [ 42.404146] save_stack_trace+0x16/0x20 [ 42.404515] save_stack+0x46/0xd0 [ 42.404827] kasan_slab_free+0x72/0xc0 [ 42.405167] kfree+0xe8/0x2b0 [ 42.405462] skb_free_head+0x74/0xb0 [ 42.405806] skb_release_data+0x30e/0x3a0 [ 42.406198] skb_release_all+0x4a/0x60 [ 42.406563] consume_skb+0x113/0x2e0 [ 42.406910] skb_free_datagram+0x1a/0xe0 [ 42.407288] netlink_recvmsg+0x60d/0xe40 [ 42.407667] sock_recvmsg+0xd7/0x110 [ 42.408022] ___sys_recvmsg+0x25c/0x580 [ 42.408395] __sys_recvmsg+0xd6/0x190 [ 42.408753] SyS_recvmsg+0x2d/0x50 [ 42.409086] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.409513] [ 42.409665] The buggy address belongs to the object at ffff88000969e780 [ 42.409665] which belongs to the cache kmalloc-512 of size 512 [ 42.410846] The buggy address is located 24 bytes inside of [ 42.410846] 512-byte region [ffff88000969e780, ffff88000969e980) [ 42.411941] The buggy address belongs to the page: [ 42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 42.413298] flags: 0x100000000008100(slab|head) [ 42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c [ 42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000 [ 42.415074] page dumped because: kasan: bad access detected [ 42.415604] [ 42.415757] Memory state around the buggy address: [ 42.416222] ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.416904] ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.418273] ^ [ 42.418588] ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419273] ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419882] ================================================================== Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-16udp: use a separate rx queue for packet receptionPaolo Abeni
under udp flood the sk_receive_queue spinlock is heavily contended. This patch try to reduce the contention on such lock adding a second receive queue to the udp sockets; recvmsg() looks first in such queue and, only if empty, tries to fetch the data from sk_receive_queue. The latter is spliced into the newly added queue every time the receive path has to acquire the sk_receive_queue lock. The accounting of forward allocated memory is still protected with the sk_receive_queue lock, so udp_rmem_release() needs to acquire both locks when the forward deficit is flushed. On specific scenarios we can end up acquiring and releasing the sk_receive_queue lock multiple times; that will be covered by the next patch Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Track alignment in BPF verifier so that legitimate programs won't be rejected on !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS architectures. 2) Make tail calls work properly in arm64 BPF JIT, from Deniel Borkmann. 3) Make the configuration and semantics Generic XDP make more sense and don't allow both generic XDP and a driver specific instance to be active at the same time. Also from Daniel. 4) Don't crash on resume in xen-netfront, from Vitaly Kuznetsov. 5) Fix use-after-free in VRF driver, from Gao Feng. 6) Use netdev_alloc_skb_ip_align() to avoid unaligned IP headers in qca_spi driver, from Stefan Wahren. 7) Always run cleanup routines in BPF samples when we get SIGTERM, from Andy Gospodarek. 8) The mdio phy code should bring PHYs out of reset using the shared GPIO lines before invoking bus->reset(). From Florian Fainelli. 9) Some USB descriptor access endian fixes in various drivers from Johan Hovold. 10) Handle PAUSE advertisements properly in mlx5 driver, from Gal Pressman. 11) Fix reversed test in mlx5e_setup_tc(), from Saeed Mahameed. 12) Cure netdev leak in AF_PACKET when using timestamping via control messages. From Douglas Caetano dos Santos. 13) netcp doesn't support HWTSTAMP_FILTER_ALl, reject it. From Miroslav Lichvar. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (52 commits) ldmvsw: stop the clean timer at beginning of remove ldmvsw: unregistering netdev before disable hardware net: netcp: fix check of requested timestamping filter ipv6: avoid dad-failures for addresses with NODAD qed: Fix uninitialized data in aRFS infrastructure mdio: mux: fix device_node_continue.cocci warnings net/packet: fix missing net_device reference release net/mlx4_core: Use min3 to select number of MSI-X vectors macvlan: Fix performance issues with vlan tagged packets net: stmmac: use correct pointer when printing normal descriptor ring net/mlx5: Use underlay QPN from the root name space net/mlx5e: IPoIB, Only support regular RQ for now net/mlx5e: Fix setup TC ndo net/mlx5e: Fix ethtool pause support and advertise reporting net/mlx5e: Use the correct pause values for ethtool advertising vmxnet3: ensure that adapter is in proper state during force_close sfc: revert changes to NIC revision numbers net: ch9200: add missing USB-descriptor endianness conversions net: irda: irda-usb: fix firmware name on big-endian hosts net: dsa: mv88e6xxx: add default case to switch ...
2017-05-15ipv6: avoid dad-failures for addresses with NODADMahesh Bandewar
Every address gets added with TENTATIVE flag even for the addresses with IFA_F_NODAD flag and dad-work is scheduled for them. During this DAD process we realize it's an address with NODAD and complete the process without sending any probe. However the TENTATIVE flags stays on the address for sometime enough to cause misinterpretation when we receive a NS. While processing NS, if the address has TENTATIVE flag, we mark it DADFAILED and endup with an address that was originally configured as NODAD with DADFAILED. We can't avoid scheduling dad_work for addresses with NODAD but we can avoid adding TENTATIVE flag to avoid this racy situation. Signed-off-by: Mahesh Bandewar <maheshb@google.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-11ipv6/dccp: do not inherit ipv6_mc_list from parentWANG Cong
Like commit 657831ffc38e ("dccp/tcp: do not inherit mc_list from parent") we should clear ipv6_mc_list etc. for IPv6 sockets too. Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-10Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The main changes are: - Debloat RCU headers - Parallelize SRCU callback handling (plus overlapping patches) - Improve the performance of Tree SRCU on a CPU-hotplug stress test - Documentation updates - Miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) rcu: Open-code the rcu_cblist_n_lazy_cbs() function rcu: Open-code the rcu_cblist_n_cbs() function rcu: Open-code the rcu_cblist_empty() function rcu: Separately compile large rcu_segcblist functions srcu: Debloat the <linux/rcu_segcblist.h> header srcu: Adjust default auto-expediting holdoff srcu: Specify auto-expedite holdoff time srcu: Expedite first synchronize_srcu() when idle srcu: Expedited grace periods with reduced memory contention srcu: Make rcutorture writer stalls print SRCU GP state srcu: Exact tracking of srcu_data structures containing callbacks srcu: Make SRCU be built by default srcu: Fix Kconfig botch when SRCU not selected rcu: Make non-preemptive schedule be Tasks RCU quiescent state srcu: Expedite srcu_schedule_cbs_snp() callback invocation srcu: Parallelize callback handling kvm: Move srcu_struct fields to end of struct kvm rcu: Fix typo in PER_RCU_NODE_PERIOD header comment rcu: Use true/false in assignment to bool rcu: Use bool value directly ...
2017-05-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix multiqueue in stmmac driver on PCI, from Andy Shevchenko. 2) cdc_ncm doesn't actually fully zero out the padding area is allocates on TX, from Jim Baxter. 3) Don't leak map addresses in BPF verifier, from Daniel Borkmann. 4) If we randomize TCP timestamps, we have to do it everywhere including SYN cookies. From Eric Dumazet. 5) Fix "ethtool -S" crash in aquantia driver, from Pavel Belous. 6) Fix allocation size for ntp filter bitmap in bnxt_en driver, from Dan Carpenter. 7) Add missing memory allocation return value check to DSA loop driver, from Christophe Jaillet. 8) Fix XDP leak on driver unload in qed driver, from Suddarsana Reddy Kalluru. 9) Don't inherit MC list from parent inet connection sockets, another syzkaller spotted gem. Fix from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits) dccp/tcp: do not inherit mc_list from parent qede: Split PF/VF ndos. qed: Correct doorbell configuration for !4Kb pages qed: Tell QM the number of tasks qed: Fix VF removal sequence qede: Fix XDP memory leak on unload net/mlx4_core: Reduce harmless SRIOV error message to debug level net/mlx4_en: Avoid adding steering rules with invalid ring net/mlx4_en: Change the error print to debug print drivers: net: wimax: i2400m: i2400m-usb: Use time_after for time comparison DECnet: Use container_of() for embedded struct Revert "ipv4: restore rt->fi for reference counting" net: mdio-mux: bcm-iproc: call mdiobus_free() in error path net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf net: cdc_ncm: Fix TX zero padding stmmac: pci: split out common_default_data() helper stmmac: pci: RX queue routing configuration stmmac: pci: TX and RX queue priority configuration stmmac: pci: set default number of rx and tx queues ...
2017-05-08net/ipv6/ila/ila_xlat.c: simplify a strange allocation patternMichal Hocko
alloc_ila_locks seemed to c&p from alloc_bucket_locks allocation pattern which is quite unusual. The default allocation size is 320 * sizeof(spinlock_t) which is sub page unless lockdep is enabled when the performance benefit is really questionable and not worth the subtle code IMHO. Also note that the context when we call ila_init_net (modprobe or a task creating a net namespace) has to be properly configured. Let's just simplify the code and use kvmalloc helper which is a transparent way to use kmalloc with vmalloc fallback. Link: http://lkml.kernel.org/r/20170306103032.2540-5-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Tom Herbert <tom@herbertland.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notfWANG Cong
For each netns (except init_net), we initialize its null entry in 3 places: 1) The template itself, as we use kmemdup() 2) Code around dst_init_metrics() in ip6_route_net_init() 3) ip6_route_dev_notify(), which is supposed to initialize it after loopback registers Unfortunately the last one still happens in a wrong order because we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to net->loopback_dev's idev, thus we have to do that after we add idev to loopback. However, this notifier has priority == 0 same as ipv6_dev_notf, and ipv6_dev_notf is registered after ip6_route_dev_notifier so it is called actually after ip6_route_dev_notifier. This is similar to commit 2f460933f58e ("ipv6: initialize route null entry in addrconf_init()") which fixes init_net. Fix it by picking a smaller priority for ip6_route_dev_notifier. Also, we have to release the refcnt accordingly when unregistering loopback_dev because device exit functions are called before subsys exit functions. Acked-by: David Ahern <dsahern@gmail.com> Tested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-05tcp: randomize timestamps on syncookiesEric Dumazet
Whole point of randomization was to hide server uptime, but an attacker can simply start a syn flood and TCP generates 'old style' timestamps, directly revealing server jiffies value. Also, TSval sent by the server to a particular remote address vary depending on syncookies being sent or not, potentially triggering PAWS drops for innocent clients. Lets implement proper randomization, including for SYNcookies. Also we do not need to export sysctl_tcp_timestamps, since it is not used from a module. In v2, I added Florian feedback and contribution, adding tsoff to tcp_get_cookie_sock(). v3 removed one unused variable in tcp_v4_connect() as Florian spotted. Fixes: 95a22caee396c ("tcp: randomize tcp timestamp offsets for each connection") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Florian Westphal <fw@strlen.de> Tested-by: Florian Westphal <fw@strlen.de> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-04ipv6: initialize route null entry in addrconf_init()WANG Cong
Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev since it is always NULL. This is clearly wrong, we have code to initialize it to loopback_dev, unfortunately the order is still not correct. loopback_dev is registered very early during boot, we lose a chance to re-initialize it in notifier. addrconf_init() is called after ip6_route_init(), which means we have no chance to correct it. Fix it by moving this initialization explicitly after ipv6_add_dev(init_net.loopback_dev) in addrconf_init(). Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-04ipv4, ipv6: ensure raw socket message is big enough to hold an IP headerAlexander Potapenko
raw_send_hdrinc() and rawv6_send_hdrinc() expect that the buffer copied from the userspace contains the IPv4/IPv6 header, so if too few bytes are copied, parts of the header may remain uninitialized. This bug has been detected with KMSAN. For the record, the KMSAN report: ================================================================== BUG: KMSAN: use of unitialized memory in nf_ct_frag6_gather+0xf5a/0x44a0 inter: 0 CPU: 0 PID: 1036 Comm: probe Not tainted 4.11.0-rc5+ #2455 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x143/0x1b0 lib/dump_stack.c:52 kmsan_report+0x16b/0x1e0 mm/kmsan/kmsan.c:1078 __kmsan_warning_32+0x5c/0xa0 mm/kmsan/kmsan_instr.c:510 nf_ct_frag6_gather+0xf5a/0x44a0 net/ipv6/netfilter/nf_conntrack_reasm.c:577 ipv6_defrag+0x1d9/0x280 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:68 nf_hook_entry_hookfn ./include/linux/netfilter.h:102 nf_hook_slow+0x13f/0x3c0 net/netfilter/core.c:310 nf_hook ./include/linux/netfilter.h:212 NF_HOOK ./include/linux/netfilter.h:255 rawv6_send_hdrinc net/ipv6/raw.c:673 rawv6_sendmsg+0x2fcb/0x41a0 net/ipv6/raw.c:919 inet_sendmsg+0x3f8/0x6d0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x6a5/0x7c0 net/socket.c:1696 SyS_sendto+0xbc/0xe0 net/socket.c:1664 do_syscall_64+0x72/0xa0 arch/x86/entry/common.c:285 entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:246 RIP: 0033:0x436e03 RSP: 002b:00007ffce48baf38 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002b0 RCX: 0000000000436e03 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffce48baf90 R08: 00007ffce48baf50 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000401790 R14: 0000000000401820 R15: 0000000000000000 origin: 00000000d9400053 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:362 kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:257 kmsan_poison_shadow+0x6d/0xc0 mm/kmsan/kmsan.c:270 slab_alloc_node mm/slub.c:2735 __kmalloc_node_track_caller+0x1f4/0x390 mm/slub.c:4341 __kmalloc_reserve net/core/skbuff.c:138 __alloc_skb+0x2cd/0x740 net/core/skbuff.c:231 alloc_skb ./include/linux/skbuff.h:933 alloc_skb_with_frags+0x209/0xbc0 net/core/skbuff.c:4678 sock_alloc_send_pskb+0x9ff/0xe00 net/core/sock.c:1903 sock_alloc_send_skb+0xe4/0x100 net/core/sock.c:1920 rawv6_send_hdrinc net/ipv6/raw.c:638 rawv6_sendmsg+0x2918/0x41a0 net/ipv6/raw.c:919 inet_sendmsg+0x3f8/0x6d0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x6a5/0x7c0 net/socket.c:1696 SyS_sendto+0xbc/0xe0 net/socket.c:1664 do_syscall_64+0x72/0xa0 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:246 ================================================================== , triggered by the following syscalls: socket(PF_INET6, SOCK_RAW, IPPROTO_RAW) = 3 sendto(3, NULL, 0, 0, {sa_family=AF_INET6, sin6_port=htons(0), inet_pton(AF_INET6, "ff00::", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = -1 EPERM A similar report is triggered in net/ipv4/raw.c if we use a PF_INET socket instead of a PF_INET6 one. Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller
Pablo Neira Ayuso says: ==================== Netfilter/IPVS/OVS fixes for net The following patchset contains a rather large batch of Netfilter, IPVS and OVS fixes for your net tree. This includes fixes for ctnetlink, the userspace conntrack helper infrastructure, conntrack OVS support, ebtables DNAT target, several leaks in error path among other. More specifically, they are: 1) Fix reference count leak in the CT target error path, from Gao Feng. 2) Remove conntrack entry clashing with a matching expectation, patch from Jarno Rajahalme. 3) Fix bogus EEXIST when registering two different userspace helpers, from Liping Zhang. 4) Don't leak dummy elements in the new bitmap set type in nf_tables, from Liping Zhang. 5) Get rid of module autoload from conntrack update path in ctnetlink, we don't need autoload at this late stage and it is happening with rcu read lock held which is not good. From Liping Zhang. 6) Fix deadlock due to double-acquire of the expect_lock from conntrack update path, this fixes a bug that was introduced when the central spinlock got removed. Again from Liping Zhang. 7) Safe ct->status update from ctnetlink path, from Liping. The expect_lock protection that was selected when the central spinlock was removed was not really protecting anything at all. 8) Protect sequence adjustment under ct->lock. 9) Missing socket match with IPv6, from Peter Tirsek. 10) Adjust skb->pkt_type of DNAT'ed frames from ebtables, from Linus Luessing. 11) Don't give up on evaluating the expression on new entries added via dynset expression in nf_tables, from Liping Zhang. 12) Use skb_checksum() when mangling icmpv6 in IPv6 NAT as this deals with non-linear skbuffs. 13) Don't allow IPv6 service in IPVS if no IPv6 support is available, from Paolo Abeni. 14) Missing mutex release in error path of xt_find_table_lock(), from Dan Carpenter. 15) Update maintainers files, Netfilter section. Add Florian to the file, refer to nftables.org and change project status from Supported to Maintained. 16) Bail out on mismatching extensions in element updates in nf_tables. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03net: ipv6: Do not duplicate DAD on link upDavid Ahern
Andrey reported a warning triggered by the rcu code: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 5911 at lib/debugobjects.c:289 debug_print_object+0x175/0x210 ODEBUG: activate active (active state 1) object type: rcu_head hint: (null) Modules linked in: CPU: 1 PID: 5911 Comm: a.out Not tainted 4.11.0-rc8+ #271 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x192/0x22d lib/dump_stack.c:52 __warn+0x19f/0x1e0 kernel/panic.c:549 warn_slowpath_fmt+0xe0/0x120 kernel/panic.c:564 debug_print_object+0x175/0x210 lib/debugobjects.c:286 debug_object_activate+0x574/0x7e0 lib/debugobjects.c:442 debug_rcu_head_queue kernel/rcu/rcu.h:75 __call_rcu.constprop.76+0xff/0x9c0 kernel/rcu/tree.c:3229 call_rcu_sched+0x12/0x20 kernel/rcu/tree.c:3288 rt6_rcu_free net/ipv6/ip6_fib.c:158 rt6_release+0x1ea/0x290 net/ipv6/ip6_fib.c:188 fib6_del_route net/ipv6/ip6_fib.c:1461 fib6_del+0xa42/0xdc0 net/ipv6/ip6_fib.c:1500 __ip6_del_rt+0x100/0x160 net/ipv6/route.c:2174 ip6_del_rt+0x140/0x1b0 net/ipv6/route.c:2187 __ipv6_ifa_notify+0x269/0x780 net/ipv6/addrconf.c:5520 addrconf_ifdown+0xe60/0x1a20 net/ipv6/addrconf.c:3672 ... Andrey's reproducer program runs in a very tight loop, calling 'unshare -n' and then spawning 2 sets of 14 threads running random ioctl calls. The relevant networking sequence: 1. New network namespace created via unshare -n - ip6tnl0 device is created in down state 2. address added to ip6tnl0 - equivalent to ip -6 addr add dev ip6tnl0 fd00::bb/1 - DAD is started on the address and when it completes the host route is inserted into the FIB 3. ip6tnl0 is brought up - the new fixup_permanent_addr function restarts DAD on the address 4. exit namespace - teardown / cleanup sequence starts - once in a blue moon, lo teardown appears to happen BEFORE teardown of ip6tunl0 + down on 'lo' removes the host route from the FIB since the dst->dev for the route is loobback + host route added to rcu callback list * rcu callback has not run yet, so rt is NOT on the gc list so it has NOT been marked obsolete 5. in parallel to 4. worker_thread runs addrconf_dad_completed - DAD on the address on ip6tnl0 completes - calls ipv6_ifa_notify which inserts the host route All of that happens very quickly. The result is that a host route that has been deleted from the IPv6 FIB and added to the RCU list is re-inserted into the FIB. The exit namespace eventually gets to cleaning up ip6tnl0 which removes the host route from the FIB again, calls the rcu function for cleanup -- and triggers the double rcu trace. The root cause is duplicate DAD on the address -- steps 2 and 3. Arguably, DAD should not be started in step 2. The interface is in the down state, so it can not really send out requests for the address which makes starting DAD pointless. Since the second DAD was introduced by a recent change, seems appropriate to use it for the Fixes tag and have the fixup function only start DAD for addresses in the PREDAD state which occurs in addrconf_ifdown if the address is retained. Big thanks to Andrey for isolating a reliable reproducer for this problem. Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David Ahern <dsahern@gmail.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>