linux-stable.git/net/ipv4, branch v4.9.22 Linux kernel stable tree tcp: initialize icsk_ack.lrcvtime at session start time 2017-03-30T07:41:22+00:00 Eric Dumazet edumazet@google.com 2017-03-22T15:10:21+00:00 9e13bcef24691b44c4de1257ba1ab6d2b8a43440 [ Upstream commit 15bb7745e94a665caf42bfaabf0ce062845b533b ] icsk_ack.lrcvtime has a 0 value at socket creation time. tcpi_last_data_recv can have bogus value if no payload is ever received. This patch initializes icsk_ack.lrcvtime for active sessions in tcp_finish_connect(), and for passive sessions in tcp_create_openreq_child() Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 15bb7745e94a665caf42bfaabf0ce062845b533b ]

icsk_ack.lrcvtime has a 0 value at socket creation time.

tcpi_last_data_recv can have bogus value if no payload is ever received.

This patch initializes icsk_ack.lrcvtime for active sessions
in tcp_finish_connect(), and for passive sessions in
tcp_create_openreq_child()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4: provide stronger user input validation in nl_fib_input() 2017-03-30T07:41:22+00:00 Eric Dumazet edumazet@google.com 2017-03-22T02:22:28+00:00 62e85fe590721acf19dfc7f8fcdd0f3eb8fc6ac5 [ Upstream commit c64c0b3cac4c5b8cb093727d2c19743ea3965c0b ] Alexander reported a KMSAN splat caused by reads of uninitialized field (tb_id_in) from user provided struct fib_result_nl It turns out nl_fib_input() sanity tests on user input is a bit wrong : User can pretend nlh->nlmsg_len is big enough, but provide at sendmsg() time a too small buffer. Reported-by: Alexander Potapenko <glider@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit c64c0b3cac4c5b8cb093727d2c19743ea3965c0b ]

Alexander reported a KMSAN splat caused by reads of uninitialized
field (tb_id_in) from user provided struct fib_result_nl

It turns out nl_fib_input() sanity tests on user input is a bit
wrong :

User can pretend nlh->nlmsg_len is big enough, but provide
at sendmsg() time a too small buffer.

Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dccp/tcp: fix routing redirect race 2017-03-22T11:43:34+00:00 Jon Maxwell jmaxwell37@gmail.com 2017-03-10T05:40:33+00:00 98933eb36dd25cb6797768bafb9b67af84e80a70 [ Upstream commit 45caeaa5ac0b4b11784ac6f932c0ad4c6b67cda0 ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320610d6 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 45caeaa5ac0b4b11784ac6f932c0ad4c6b67cda0 ]

As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.

We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:

 #8 [] page_fault at ffffffff8163e648
    [exception RIP: __tcp_ack_snd_check+74]
.
.
 #9 [] tcp_rcv_established at ffffffff81580b64
#10 [] tcp_v4_do_rcv at ffffffff8158b54a
#11 [] tcp_v4_rcv at ffffffff8158cd02
#12 [] ip_local_deliver_finish at ffffffff815668f4
#13 [] ip_local_deliver at ffffffff81566bd9
#14 [] ip_rcv_finish at ffffffff8156656d
#15 [] ip_rcv at ffffffff81566f06
#16 [] __netif_receive_skb_core at ffffffff8152b3a2
#17 [] __netif_receive_skb at ffffffff8152b608
#18 [] netif_receive_skb at ffffffff8152b690
#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
#21 [] net_rx_action at ffffffff8152bac2
#22 [] __do_softirq at ffffffff81084b4f
#23 [] call_softirq at ffffffff8164845c
#24 [] do_softirq at ffffffff81016fc5
#25 [] irq_exit at ffffffff81084ee5
#26 [] do_IRQ at ffffffff81648ff8

Of course it may happen with other NIC drivers as well.

It's found the freed dst_entry here:

 224 static bool tcp_in_quickack_mode(struct sock *sk)↩
 225 {↩
 226 ▹       const struct inet_connection_sock *icsk = inet_csk(sk);↩
 227 ▹       const struct dst_entry *dst = __sk_dst_get(sk);↩
 228 ↩
 229 ▹       return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
 230 ▹       ▹       (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
 231 }↩

But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.

All the vmcores showed 2 significant clues:

- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.

- All vmcores showed a postitive LockDroppedIcmps value, e.g:

LockDroppedIcmps                  267

A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:

do_redirect()->__sk_dst_check()-> dst_release().

Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.

To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.

The dccp/IPv6 code is very similar in this respect, so fixing it there too.

As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().

Fixes: ceb3320610d6 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/tunnel: set inner protocol in network gro hooks 2017-03-22T11:43:34+00:00 Paolo Abeni pabeni@redhat.com 2017-03-07T17:33:31+00:00 b07eed8f7119d43cbfe4d2d66241bd04099e6585 [ Upstream commit 294acf1c01bace5cea5d30b510504238bf5f7c25 ] The gso code of several tunnels type (gre and udp tunnels) takes for granted that the skb->inner_protocol is properly initialized and drops the packet elsewhere. On the forwarding path no one is initializing such field, so gro encapsulated packets are dropped on forward. Since commit 38720352412a ("gre: Use inner_proto to obtain inner header protocol"), this can be reproduced when the encapsulated packets use gre as the tunneling protocol. The issue happens also with vxlan and geneve tunnels since commit 8bce6d7d0d1e ("udp: Generalize skb_udp_segment"), if the forwarding host's ingress nic has h/w offload for such tunnel and a vxlan/geneve device is configured on top of it, regardless of the configured peer address and vni. To address the issue, this change initialize the inner_protocol field for encapsulated packets in both ipv4 and ipv6 gro complete callbacks. Fixes: 38720352412a ("gre: Use inner_proto to obtain inner header protocol") Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 294acf1c01bace5cea5d30b510504238bf5f7c25 ]

The gso code of several tunnels type (gre and udp tunnels)
takes for granted that the skb->inner_protocol is properly
initialized and drops the packet elsewhere.

On the forwarding path no one is initializing such field,
so gro encapsulated packets are dropped on forward.

Since commit 38720352412a ("gre: Use inner_proto to obtain
inner header protocol"), this can be reproduced when the
encapsulated packets use gre as the tunneling protocol.

The issue happens also with vxlan and geneve tunnels since
commit 8bce6d7d0d1e ("udp: Generalize skb_udp_segment"), if the
forwarding host's ingress nic has h/w offload for such tunnel
and a vxlan/geneve device is configured on top of it, regardless
of the configured peer address and vni.

To address the issue, this change initialize the inner_protocol
field for encapsulated packets in both ipv4 and ipv6 gro complete
callbacks.

Fixes: 38720352412a ("gre: Use inner_proto to obtain inner header protocol")
Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: fix various issues for sockets morphing to listen state 2017-03-22T11:43:33+00:00 Eric Dumazet edumazet@google.com 2017-03-03T22:08:21+00:00 07753bc6a2816c1c3b9f7bff133251f623c7bc91 [ Upstream commit 02b2faaf0af1d85585f6d6980e286d53612acfc2 ] Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting tcp_disconnect() path that was never really considered and/or used before syzkaller ;) I was not able to reproduce the bug, but it seems issues here are the three possible actions that assumed they would never trigger on a listener. 1) tcp_write_timer_handler 2) tcp_delack_timer_handler 3) MTU reduction Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN states from tcp_v6_mtu_reduced() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 02b2faaf0af1d85585f6d6980e286d53612acfc2 ]

Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting
tcp_disconnect() path that was never really considered and/or used
before syzkaller ;)

I was not able to reproduce the bug, but it seems issues here are the
three possible actions that assumed they would never trigger on a
listener.

1) tcp_write_timer_handler
2) tcp_delack_timer_handler
3) MTU reduction

Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN
 states from tcp_v6_mtu_reduced()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp/dccp: block BH for SYN processing 2017-03-22T11:43:32+00:00 Eric Dumazet edumazet@google.com 2017-03-01T16:39:49+00:00 bbaeb9b73fa890dd7a6fa379a7e4822687643a4e [ Upstream commit 449809a66c1d0b1563dee84493e14bf3104d2d7e ] SYN processing really was meant to be handled from BH. When I got rid of BH blocking while processing socket backlog in commit 5413d1babe8f ("net: do not block BH while processing socket backlog"), I forgot that a malicious user could transition to TCP_LISTEN from a state that allowed (SYN) packets to be parked in the socket backlog while socket is owned by the thread doing the listen() call. Sure enough syzkaller found this and reported the bug ;) ================================= [ INFO: inconsistent lock state ] 4.10.0+ #60 Not tainted --------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. syz-executor0/5090 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at: [<ffffffff83a6a370>] spin_lock include/linux/spinlock.h:299 [inline] (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at: [<ffffffff83a6a370>] inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407 {IN-SOFTIRQ-W} state was registered at: mark_irqflags kernel/locking/lockdep.c:2923 [inline] __lock_acquire+0xbcf/0x3270 kernel/locking/lockdep.c:3295 lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline] inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764 tcp_conn_request+0x25cc/0x3310 net/ipv4/tcp_input.c:6399 tcp_v4_conn_request+0x157/0x220 net/ipv4/tcp_ipv4.c:1262 tcp_rcv_state_process+0x802/0x4130 net/ipv4/tcp_input.c:5889 tcp_v4_do_rcv+0x56b/0x940 net/ipv4/tcp_ipv4.c:1433 tcp_v4_rcv+0x2e12/0x3210 net/ipv4/tcp_ipv4.c:1711 ip_local_deliver_finish+0x4ce/0xc40 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:257 [inline] ip_local_deliver+0x1ce/0x710 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:492 [inline] ip_rcv_finish+0xb1d/0x2110 net/ipv4/ip_input.c:396 NF_HOOK include/linux/netfilter.h:257 [inline] ip_rcv+0xd90/0x19c0 net/ipv4/ip_input.c:487 __netif_receive_skb_core+0x1ad1/0x3400 net/core/dev.c:4179 __netif_receive_skb+0x2a/0x170 net/core/dev.c:4217 netif_receive_skb_internal+0x1d6/0x430 net/core/dev.c:4245 napi_skb_finish net/core/dev.c:4602 [inline] napi_gro_receive+0x4e6/0x680 net/core/dev.c:4636 e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4033 [inline] e1000_clean_rx_irq+0x5e0/0x1490 drivers/net/ethernet/intel/e1000/e1000_main.c:4489 e1000_clean+0xb9a/0x2910 drivers/net/ethernet/intel/e1000/e1000_main.c:3834 napi_poll net/core/dev.c:5171 [inline] net_rx_action+0xe70/0x1900 net/core/dev.c:5236 __do_softirq+0x2fb/0xb7d kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x19e/0x1d0 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:658 [inline] do_IRQ+0x81/0x1a0 arch/x86/kernel/irq.c:250 ret_from_intr+0x0/0x20 native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53 arch_safe_halt arch/x86/include/asm/paravirt.h:98 [inline] default_idle+0x8f/0x410 arch/x86/kernel/process.c:271 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:262 default_idle_call+0x36/0x60 kernel/sched/idle.c:96 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x348/0x440 kernel/sched/idle.c:243 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:345 start_secondary+0x344/0x440 arch/x86/kernel/smpboot.c:272 verify_cpu+0x0/0xfc irq event stamp: 1741 hardirqs last enabled at (1741): [<ffffffff84d49d77>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (1741): [<ffffffff84d49d77>] _raw_spin_unlock_irqrestore+0xf7/0x1a0 kernel/locking/spinlock.c:191 hardirqs last disabled at (1740): [<ffffffff84d4a732>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (1740): [<ffffffff84d4a732>] _raw_spin_lock_irqsave+0xa2/0x110 kernel/locking/spinlock.c:159 softirqs last enabled at (1738): [<ffffffff84d4deff>] __do_softirq+0x7cf/0xb7d kernel/softirq.c:310 softirqs last disabled at (1571): [<ffffffff84d4b92c>] do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&hashinfo->ehash_locks[i])->rlock); <Interrupt> lock(&(&hashinfo->ehash_locks[i])->rlock); *** DEADLOCK *** 1 lock held by syz-executor0/5090: #0: (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>] lock_sock include/net/sock.h:1460 [inline] #0: (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>] sock_setsockopt+0x233/0x1e40 net/core/sock.c:683 stack backtrace: CPU: 1 PID: 5090 Comm: syz-executor0 Not tainted 4.10.0+ #60 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:15 [inline] dump_stack+0x292/0x398 lib/dump_stack.c:51 print_usage_bug+0x3ef/0x450 kernel/locking/lockdep.c:2387 valid_state kernel/locking/lockdep.c:2400 [inline] mark_lock_irq kernel/locking/lockdep.c:2602 [inline] mark_lock+0xf30/0x1410 kernel/locking/lockdep.c:3065 mark_irqflags kernel/locking/lockdep.c:2941 [inline] __lock_acquire+0x6dc/0x3270 kernel/locking/lockdep.c:3295 lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:299 [inline] inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline] inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764 dccp_v6_conn_request+0xada/0x11b0 net/dccp/ipv6.c:380 dccp_rcv_state_process+0x51e/0x1660 net/dccp/input.c:606 dccp_v6_do_rcv+0x213/0x350 net/dccp/ipv6.c:632 sk_backlog_rcv include/net/sock.h:896 [inline] __release_sock+0x127/0x3a0 net/core/sock.c:2052 release_sock+0xa5/0x2b0 net/core/sock.c:2539 sock_setsockopt+0x60f/0x1e40 net/core/sock.c:1016 SYSC_setsockopt net/socket.c:1782 [inline] SyS_setsockopt+0x2fb/0x3a0 net/socket.c:1765 entry_SYSCALL_64_fastpath+0x1f/0xc2 RIP: 0033:0x4458b9 RSP: 002b:00007fe8b26c2b58 EFLAGS: 00000292 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004458b9 RDX: 000000000000001a RSI: 0000000000000001 RDI: 0000000000000006 RBP: 00000000006e2110 R08: 0000000000000010 R09: 0000000000000000 R10: 00000000208c3000 R11: 0000000000000292 R12: 0000000000708000 R13: 0000000020000000 R14: 0000000000001000 R15: 0000000000000000 Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 449809a66c1d0b1563dee84493e14bf3104d2d7e ]

SYN processing really was meant to be handled from BH.

When I got rid of BH blocking while processing socket backlog
in commit 5413d1babe8f ("net: do not block BH while processing socket
backlog"), I forgot that a malicious user could transition to TCP_LISTEN
from a state that allowed (SYN) packets to be parked in the socket
backlog while socket is owned by the thread doing the listen() call.

Sure enough syzkaller found this and reported the bug ;)

=================================
[ INFO: inconsistent lock state ]
4.10.0+ #60 Not tainted
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
syz-executor0/5090 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at:
[<ffffffff83a6a370>] spin_lock include/linux/spinlock.h:299 [inline]
 (&(&hashinfo->ehash_locks[i])->rlock){+.?...}, at:
[<ffffffff83a6a370>] inet_ehash_insert+0x240/0xad0
net/ipv4/inet_hashtables.c:407
{IN-SOFTIRQ-W} state was registered at:
  mark_irqflags kernel/locking/lockdep.c:2923 [inline]
  __lock_acquire+0xbcf/0x3270 kernel/locking/lockdep.c:3295
  lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
  spin_lock include/linux/spinlock.h:299 [inline]
  inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407
  reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline]
  inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764
  tcp_conn_request+0x25cc/0x3310 net/ipv4/tcp_input.c:6399
  tcp_v4_conn_request+0x157/0x220 net/ipv4/tcp_ipv4.c:1262
  tcp_rcv_state_process+0x802/0x4130 net/ipv4/tcp_input.c:5889
  tcp_v4_do_rcv+0x56b/0x940 net/ipv4/tcp_ipv4.c:1433
  tcp_v4_rcv+0x2e12/0x3210 net/ipv4/tcp_ipv4.c:1711
  ip_local_deliver_finish+0x4ce/0xc40 net/ipv4/ip_input.c:216
  NF_HOOK include/linux/netfilter.h:257 [inline]
  ip_local_deliver+0x1ce/0x710 net/ipv4/ip_input.c:257
  dst_input include/net/dst.h:492 [inline]
  ip_rcv_finish+0xb1d/0x2110 net/ipv4/ip_input.c:396
  NF_HOOK include/linux/netfilter.h:257 [inline]
  ip_rcv+0xd90/0x19c0 net/ipv4/ip_input.c:487
  __netif_receive_skb_core+0x1ad1/0x3400 net/core/dev.c:4179
  __netif_receive_skb+0x2a/0x170 net/core/dev.c:4217
  netif_receive_skb_internal+0x1d6/0x430 net/core/dev.c:4245
  napi_skb_finish net/core/dev.c:4602 [inline]
  napi_gro_receive+0x4e6/0x680 net/core/dev.c:4636
  e1000_receive_skb drivers/net/ethernet/intel/e1000/e1000_main.c:4033 [inline]
  e1000_clean_rx_irq+0x5e0/0x1490
drivers/net/ethernet/intel/e1000/e1000_main.c:4489
  e1000_clean+0xb9a/0x2910 drivers/net/ethernet/intel/e1000/e1000_main.c:3834
  napi_poll net/core/dev.c:5171 [inline]
  net_rx_action+0xe70/0x1900 net/core/dev.c:5236
  __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
  invoke_softirq kernel/softirq.c:364 [inline]
  irq_exit+0x19e/0x1d0 kernel/softirq.c:405
  exiting_irq arch/x86/include/asm/apic.h:658 [inline]
  do_IRQ+0x81/0x1a0 arch/x86/kernel/irq.c:250
  ret_from_intr+0x0/0x20
  native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:53
  arch_safe_halt arch/x86/include/asm/paravirt.h:98 [inline]
  default_idle+0x8f/0x410 arch/x86/kernel/process.c:271
  arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:262
  default_idle_call+0x36/0x60 kernel/sched/idle.c:96
  cpuidle_idle_call kernel/sched/idle.c:154 [inline]
  do_idle+0x348/0x440 kernel/sched/idle.c:243
  cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:345
  start_secondary+0x344/0x440 arch/x86/kernel/smpboot.c:272
  verify_cpu+0x0/0xfc
irq event stamp: 1741
hardirqs last  enabled at (1741): [<ffffffff84d49d77>]
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160
[inline]
hardirqs last  enabled at (1741): [<ffffffff84d49d77>]
_raw_spin_unlock_irqrestore+0xf7/0x1a0 kernel/locking/spinlock.c:191
hardirqs last disabled at (1740): [<ffffffff84d4a732>]
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (1740): [<ffffffff84d4a732>]
_raw_spin_lock_irqsave+0xa2/0x110 kernel/locking/spinlock.c:159
softirqs last  enabled at (1738): [<ffffffff84d4deff>]
__do_softirq+0x7cf/0xb7d kernel/softirq.c:310
softirqs last disabled at (1571): [<ffffffff84d4b92c>]
do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&hashinfo->ehash_locks[i])->rlock);
  <Interrupt>
    lock(&(&hashinfo->ehash_locks[i])->rlock);

 *** DEADLOCK ***

1 lock held by syz-executor0/5090:
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>] lock_sock
include/net/sock.h:1460 [inline]
 #0:  (sk_lock-AF_INET6){+.+.+.}, at: [<ffffffff83406b43>]
sock_setsockopt+0x233/0x1e40 net/core/sock.c:683

stack backtrace:
CPU: 1 PID: 5090 Comm: syz-executor0 Not tainted 4.10.0+ #60
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:15 [inline]
 dump_stack+0x292/0x398 lib/dump_stack.c:51
 print_usage_bug+0x3ef/0x450 kernel/locking/lockdep.c:2387
 valid_state kernel/locking/lockdep.c:2400 [inline]
 mark_lock_irq kernel/locking/lockdep.c:2602 [inline]
 mark_lock+0xf30/0x1410 kernel/locking/lockdep.c:3065
 mark_irqflags kernel/locking/lockdep.c:2941 [inline]
 __lock_acquire+0x6dc/0x3270 kernel/locking/lockdep.c:3295
 lock_acquire+0x241/0x580 kernel/locking/lockdep.c:3753
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x33/0x50 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:299 [inline]
 inet_ehash_insert+0x240/0xad0 net/ipv4/inet_hashtables.c:407
 reqsk_queue_hash_req net/ipv4/inet_connection_sock.c:753 [inline]
 inet_csk_reqsk_queue_hash_add+0x1b7/0x2a0 net/ipv4/inet_connection_sock.c:764
 dccp_v6_conn_request+0xada/0x11b0 net/dccp/ipv6.c:380
 dccp_rcv_state_process+0x51e/0x1660 net/dccp/input.c:606
 dccp_v6_do_rcv+0x213/0x350 net/dccp/ipv6.c:632
 sk_backlog_rcv include/net/sock.h:896 [inline]
 __release_sock+0x127/0x3a0 net/core/sock.c:2052
 release_sock+0xa5/0x2b0 net/core/sock.c:2539
 sock_setsockopt+0x60f/0x1e40 net/core/sock.c:1016
 SYSC_setsockopt net/socket.c:1782 [inline]
 SyS_setsockopt+0x2fb/0x3a0 net/socket.c:1765
 entry_SYSCALL_64_fastpath+0x1f/0xc2
RIP: 0033:0x4458b9
RSP: 002b:00007fe8b26c2b58 EFLAGS: 00000292 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00000000004458b9
RDX: 000000000000001a RSI: 0000000000000001 RDI: 0000000000000006
RBP: 00000000006e2110 R08: 0000000000000010 R09: 0000000000000000
R10: 00000000208c3000 R11: 0000000000000292 R12: 0000000000708000
R13: 0000000020000000 R14: 0000000000001000 R15: 0000000000000000

Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv4: mask tos for input route 2017-03-22T11:43:32+00:00 Julian Anastasov ja@ssi.bg 2017-02-26T15:14:35+00:00 36931eb015ee44fe2c8f220b46500b25f7282442 [ Upstream commit 6e28099d38c0e50d62c1afc054e37e573adf3d21 ] Restore the lost masking of TOS in input route code to allow ip rules to match it properly. Problem [1] noticed by Shmulik Ladkani <shmulik.ladkani@gmail.com> [1] http://marc.info/?t=137331755300040&r=1&w=2 Fixes: 89aef8921bfb ("ipv4: Delete routing cache.") Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 6e28099d38c0e50d62c1afc054e37e573adf3d21 ]

Restore the lost masking of TOS in input route code to
allow ip rules to match it properly.

Problem [1] noticed by Shmulik Ladkani <shmulik.ladkani@gmail.com>

[1] http://marc.info/?t=137331755300040&r=1&w=2

Fixes: 89aef8921bfb ("ipv4: Delete routing cache.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ip: fix IP_CHECKSUM handling 2017-02-26T10:10:51+00:00 Paolo Abeni pabeni@redhat.com 2017-02-21T08:33:18+00:00 481aedf869fbf2d4503ca0005dbd68b78422955a [ Upstream commit ca4ef4574f1ee5252e2cd365f8f5d5bafd048f32 ] The skbs processed by ip_cmsg_recv() are not guaranteed to be linear e.g. when sending UDP packets over loopback with MSGMORE. Using csum_partial() on [potentially] the whole skb len is dangerous; instead be on the safe side and use skb_checksum(). Thanks to syzkaller team to detect the issue and provide the reproducer. v1 -> v2: - move the variable declaration in a tighter scope Fixes: ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv") Reported-by: Andrey Konovalov <andreyknvl@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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit ca4ef4574f1ee5252e2cd365f8f5d5bafd048f32 ]

The skbs processed by ip_cmsg_recv() are not guaranteed to
be linear e.g. when sending UDP packets over loopback with
MSGMORE.
Using csum_partial() on [potentially] the whole skb len
is dangerous; instead be on the safe side and use skb_checksum().

Thanks to syzkaller team to detect the issue and provide the
reproducer.

v1 -> v2:
 - move the variable declaration in a tighter scope

Fixes: ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv")
Reported-by: Andrey Konovalov <andreyknvl@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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: fix mark propagation with fwmark_reflect enabled 2017-02-18T14:11:43+00:00 Pau Espin Pedrol pespin.shar@gmail.com 2017-01-06T19:33:28+00:00 7c4c32a2976e061f3cc9cecf54ad20dd8861a212 commit bf99b4ded5f8a4767dbb9d180626f06c51f9881f upstream. Otherwise, RST packets generated by the TCP stack for non-existing sockets always have mark 0. The mark from the original packet is assigned to the netns_ipv4/6 socket used to send the response so that it can get copied into the response skb when the socket sends it. Fixes: e110861f8609 ("net: add a sysctl to reflect the fwmark on replies") Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Pau Espin Pedrol <pau.espin@tessares.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bf99b4ded5f8a4767dbb9d180626f06c51f9881f upstream.

Otherwise, RST packets generated by the TCP stack for non-existing
sockets always have mark 0.
The mark from the original packet is assigned to the netns_ipv4/6
socket used to send the response so that it can get copied into the
response skb when the socket sends it.

Fixes: e110861f8609 ("net: add a sysctl to reflect the fwmark on replies")
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Pau Espin Pedrol <pau.espin@tessares.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
igmp, mld: Fix memory leak in igmpv3/mld_del_delrec() 2017-02-18T14:11:43+00:00 Hangbin Liu liuhangbin@gmail.com 2017-02-08T13:16:45+00:00 16a3fbe5239a5ca054b0544abdd661076ec4f1c5 [ Upstream commit 9c8bb163ae784be4f79ae504e78c862806087c54 ] In function igmpv3/mld_add_delrec() we allocate pmc and put it in idev->mc_tomb, so we should free it when we don't need it in del_delrec(). But I removed kfree(pmc) incorrectly in latest two patches. Now fix it. Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when ...") Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when ...") Reported-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 9c8bb163ae784be4f79ae504e78c862806087c54 ]

In function igmpv3/mld_add_delrec() we allocate pmc and put it in
idev->mc_tomb, so we should free it when we don't need it in del_delrec().
But I removed kfree(pmc) incorrectly in latest two patches. Now fix it.

Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when ...")
Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when ...")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>