linux.git/net/tipc, branch v4.13 Linux kernel source tree tipc: permit bond slave as bearer 2017-08-29T22:07:33+00:00 Parthasarathy Bhuvaragan parthasarathy.bhuvaragan@ericsson.com 2017-08-28T15:57:02+00:00 d55c60eba0ef44ec21831ce26db300763eafd865 For a bond slave device as a tipc bearer, the dev represents the bond interface and orig_dev represents the slave in tipc_l2_rcv_msg(). Since we decode the tipc_ptr from bonding device (dev), we fail to find the bearer and thus tipc links are not established. In this commit, we register the tipc protocol callback per device and look for tipc bearer from both the devices. Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
For a bond slave device as a tipc bearer, the dev represents the bond
interface and orig_dev represents the slave in tipc_l2_rcv_msg().
Since we decode the tipc_ptr from bonding device (dev), we fail to
find the bearer and thus tipc links are not established.

In this commit, we register the tipc protocol callback per device and
look for tipc bearer from both the devices.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: context imbalance at node read unlock 2017-08-25T04:54:34+00:00 Parthasarathy Bhuvaragan parthasarathy.bhuvaragan@ericsson.com 2017-08-24T14:31:24+00:00 991ca84daa001193066554fa49f3a934746317d6 If we fail to find a valid bearer in tipc_node_get_linkname(), node_read_unlock() is called without holding the node read lock. This commit fixes this error. Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
If we fail to find a valid bearer in tipc_node_get_linkname(),
node_read_unlock() is called without holding the node read lock.

This commit fixes this error.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: reassign pointers after skb reallocation / linearization 2017-08-25T04:54:34+00:00 Parthasarathy Bhuvaragan parthasarathy.bhuvaragan@ericsson.com 2017-08-24T14:31:23+00:00 60d1d93664a0bb3d5af722ed38c57ee165a45bf7 In tipc_msg_reverse(), we assign skb attributes to local pointers in stack at startup. This is followed by skb_linearize() and for cloned buffers we perform skb relocation using pskb_expand_head(). Both these methods may update the skb attributes and thus making the pointers incorrect. In this commit, we fix this error by ensuring that the pointers are re-assigned after any of these skb operations. Fixes: 29042e19f2c60 ("tipc: let function tipc_msg_reverse() expand header when needed") Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
In tipc_msg_reverse(), we assign skb attributes to local pointers
in stack at startup. This is followed by skb_linearize() and for
cloned buffers we perform skb relocation using pskb_expand_head().
Both these methods may update the skb attributes and thus making
the pointers incorrect.

In this commit, we fix this error by ensuring that the pointers
are re-assigned after any of these skb operations.

Fixes: 29042e19f2c60 ("tipc: let function tipc_msg_reverse() expand header
when needed")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: perform skb_linearize() before parsing the inner header 2017-08-25T04:54:34+00:00 Parthasarathy Bhuvaragan parthasarathy.bhuvaragan@ericsson.com 2017-08-24T14:31:22+00:00 27163138b4d80e36f2006273d66b6c122d241f30 In tipc_rcv(), we linearize only the header and usually the packets are consumed as the nodes permit direct reception. However, if the skb contains tunnelled message due to fail over or synchronization we parse it in tipc_node_check_state() without performing linearization. This will cause link disturbances if the skb was non linear. In this commit, we perform linearization for the above messages. Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
In tipc_rcv(), we linearize only the header and usually the packets
are consumed as the nodes permit direct reception. However, if the
skb contains tunnelled message due to fail over or synchronization
we parse it in tipc_node_check_state() without performing
linearization. This will cause link disturbances if the skb was
non linear.

In this commit, we perform linearization for the above messages.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: Fix tipc_sk_reinit handling of -EAGAIN 2017-08-24T21:02:26+00:00 Bob Peterson rpeterso@redhat.com 2017-08-23T14:43:02+00:00 6c7e983b220f89e03286dc70a41c7ef3a8b409df In 9dbbfb0ab6680c6a85609041011484e6658e7d3c function tipc_sk_reinit had additional logic added to loop in the event that function rhashtable_walk_next() returned -EAGAIN. No worries. However, if rhashtable_walk_start returns -EAGAIN, it does "continue", and therefore skips the call to rhashtable_walk_stop(). That has the effect of calling rcu_read_lock() without its paired call to rcu_read_unlock(). Since rcu_read_lock() may be nested, the problem may not be apparent for a while, especially since resize events may be rare. But the comments to rhashtable_walk_start() state: * ...Note that we take the RCU lock in all * cases including when we return an error. So you must always call * rhashtable_walk_stop to clean up. This patch replaces the continue with a goto and label to ensure a matching call to rhashtable_walk_stop(). Signed-off-by: Bob Peterson <rpeterso@redhat.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> 
In 9dbbfb0ab6680c6a85609041011484e6658e7d3c function tipc_sk_reinit
had additional logic added to loop in the event that function
rhashtable_walk_next() returned -EAGAIN. No worries.

However, if rhashtable_walk_start returns -EAGAIN, it does "continue",
and therefore skips the call to rhashtable_walk_stop(). That has
the effect of calling rcu_read_lock() without its paired call to
rcu_read_unlock(). Since rcu_read_lock() may be nested, the problem
may not be apparent for a while, especially since resize events may
be rare. But the comments to rhashtable_walk_start() state:

 * ...Note that we take the RCU lock in all
 * cases including when we return an error.  So you must always call
 * rhashtable_walk_stop to clean up.

This patch replaces the continue with a goto and label to ensure a
matching call to rhashtable_walk_stop().

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: fix a race condition of releasing subscriber object 2017-08-22T21:25:02+00:00 Ying Xue ying.xue@windriver.com 2017-08-22T10:28:41+00:00 fd849b7c41f0fabfe783d0691a63c5518e8ebc99 No matter whether a request is inserted into workqueue as a work item to cancel a subscription or to delete a subscription's subscriber asynchronously, the work items may be executed in different workers. As a result, it doesn't mean that one request which is raised prior to another request is definitely handled before the latter. By contrast, if the latter request is executed before the former request, below error may happen: [ 656.183644] BUG: spinlock bad magic on CPU#0, kworker/u8:0/12117 [ 656.184487] general protection fault: 0000 [#1] SMP [ 656.185160] Modules linked in: tipc ip6_udp_tunnel udp_tunnel 9pnet_virtio 9p 9pnet virtio_net virtio_pci virtio_ring virtio [last unloaded: ip6_udp_tunnel] [ 656.187003] CPU: 0 PID: 12117 Comm: kworker/u8:0 Not tainted 4.11.0-rc7+ #6 [ 656.187920] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 656.188690] Workqueue: tipc_rcv tipc_recv_work [tipc] [ 656.189371] task: ffff88003f5cec40 task.stack: ffffc90004448000 [ 656.190157] RIP: 0010:spin_bug+0xdd/0xf0 [ 656.190678] RSP: 0018:ffffc9000444bcb8 EFLAGS: 00010202 [ 656.191375] RAX: 0000000000000034 RBX: ffff88003f8d1388 RCX: 0000000000000000 [ 656.192321] RDX: ffff88003ba13708 RSI: ffff88003ba0cd08 RDI: ffff88003ba0cd08 [ 656.193265] RBP: ffffc9000444bcd0 R08: 0000000000000030 R09: 000000006b6b6b6b [ 656.194208] R10: ffff8800bde3e000 R11: 00000000000001b4 R12: 6b6b6b6b6b6b6b6b [ 656.195157] R13: ffffffff81a3ca64 R14: ffff88003f8d1388 R15: ffff88003f8d13a0 [ 656.196101] FS: 0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000 [ 656.197172] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 656.197935] CR2: 00007f0b3d2e6000 CR3: 000000003ef9e000 CR4: 00000000000006f0 [ 656.198873] Call Trace: [ 656.199210] do_raw_spin_lock+0x66/0xa0 [ 656.199735] _raw_spin_lock_bh+0x19/0x20 [ 656.200258] tipc_subscrb_subscrp_delete+0x28/0xf0 [tipc] [ 656.200990] tipc_subscrb_rcv_cb+0x45/0x260 [tipc] [ 656.201632] tipc_receive_from_sock+0xaf/0x100 [tipc] [ 656.202299] tipc_recv_work+0x2b/0x60 [tipc] [ 656.202872] process_one_work+0x157/0x420 [ 656.203404] worker_thread+0x69/0x4c0 [ 656.203898] kthread+0x138/0x170 [ 656.204328] ? process_one_work+0x420/0x420 [ 656.204889] ? kthread_create_on_node+0x40/0x40 [ 656.205527] ret_from_fork+0x29/0x40 [ 656.206012] Code: 48 8b 0c 25 00 c5 00 00 48 c7 c7 f0 24 a3 81 48 81 c1 f0 05 00 00 65 8b 15 61 ef f5 7e e8 9a 4c 09 00 4d 85 e4 44 8b 4b 08 74 92 <45> 8b 84 24 40 04 00 00 49 8d 8c 24 f0 05 00 00 eb 8d 90 0f 1f [ 656.208504] RIP: spin_bug+0xdd/0xf0 RSP: ffffc9000444bcb8 [ 656.209798] ---[ end trace e2a800e6eb0770be ]--- In above scenario, the request of deleting subscriber was performed earlier than the request of canceling a subscription although the latter was issued before the former, which means tipc_subscrb_delete() was called before tipc_subscrp_cancel(). As a result, when tipc_subscrb_subscrp_delete() called by tipc_subscrp_cancel() was executed to cancel a subscription, the subscription's subscriber refcnt had been decreased to 1. After tipc_subscrp_delete() where the subscriber was freed because its refcnt was decremented to zero, but the subscriber's lock had to be released, as a consequence, panic happened. By contrast, if we increase subscriber's refcnt before tipc_subscrb_subscrp_delete() is called in tipc_subscrp_cancel(), the panic issue can be avoided. Fixes: d094c4d5f5c7 ("tipc: add subscription refcount to avoid invalid delete") Reported-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
No matter whether a request is inserted into workqueue as a work item
to cancel a subscription or to delete a subscription's subscriber
asynchronously, the work items may be executed in different workers.
As a result, it doesn't mean that one request which is raised prior to
another request is definitely handled before the latter. By contrast,
if the latter request is executed before the former request, below
error may happen:

[  656.183644] BUG: spinlock bad magic on CPU#0, kworker/u8:0/12117
[  656.184487] general protection fault: 0000 [#1] SMP
[  656.185160] Modules linked in: tipc ip6_udp_tunnel udp_tunnel 9pnet_virtio 9p 9pnet virtio_net virtio_pci virtio_ring virtio [last unloaded: ip6_udp_tunnel]
[  656.187003] CPU: 0 PID: 12117 Comm: kworker/u8:0 Not tainted 4.11.0-rc7+ #6
[  656.187920] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  656.188690] Workqueue: tipc_rcv tipc_recv_work [tipc]
[  656.189371] task: ffff88003f5cec40 task.stack: ffffc90004448000
[  656.190157] RIP: 0010:spin_bug+0xdd/0xf0
[  656.190678] RSP: 0018:ffffc9000444bcb8 EFLAGS: 00010202
[  656.191375] RAX: 0000000000000034 RBX: ffff88003f8d1388 RCX: 0000000000000000
[  656.192321] RDX: ffff88003ba13708 RSI: ffff88003ba0cd08 RDI: ffff88003ba0cd08
[  656.193265] RBP: ffffc9000444bcd0 R08: 0000000000000030 R09: 000000006b6b6b6b
[  656.194208] R10: ffff8800bde3e000 R11: 00000000000001b4 R12: 6b6b6b6b6b6b6b6b
[  656.195157] R13: ffffffff81a3ca64 R14: ffff88003f8d1388 R15: ffff88003f8d13a0
[  656.196101] FS:  0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000
[  656.197172] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  656.197935] CR2: 00007f0b3d2e6000 CR3: 000000003ef9e000 CR4: 00000000000006f0
[  656.198873] Call Trace:
[  656.199210]  do_raw_spin_lock+0x66/0xa0
[  656.199735]  _raw_spin_lock_bh+0x19/0x20
[  656.200258]  tipc_subscrb_subscrp_delete+0x28/0xf0 [tipc]
[  656.200990]  tipc_subscrb_rcv_cb+0x45/0x260 [tipc]
[  656.201632]  tipc_receive_from_sock+0xaf/0x100 [tipc]
[  656.202299]  tipc_recv_work+0x2b/0x60 [tipc]
[  656.202872]  process_one_work+0x157/0x420
[  656.203404]  worker_thread+0x69/0x4c0
[  656.203898]  kthread+0x138/0x170
[  656.204328]  ? process_one_work+0x420/0x420
[  656.204889]  ? kthread_create_on_node+0x40/0x40
[  656.205527]  ret_from_fork+0x29/0x40
[  656.206012] Code: 48 8b 0c 25 00 c5 00 00 48 c7 c7 f0 24 a3 81 48 81 c1 f0 05 00 00 65 8b 15 61 ef f5 7e e8 9a 4c 09 00 4d 85 e4 44 8b 4b 08 74 92 <45> 8b 84 24 40 04 00 00 49 8d 8c 24 f0 05 00 00 eb 8d 90 0f 1f
[  656.208504] RIP: spin_bug+0xdd/0xf0 RSP: ffffc9000444bcb8
[  656.209798] ---[ end trace e2a800e6eb0770be ]---

In above scenario, the request of deleting subscriber was performed
earlier than the request of canceling a subscription although the
latter was issued before the former, which means tipc_subscrb_delete()
was called before tipc_subscrp_cancel(). As a result, when
tipc_subscrb_subscrp_delete() called by tipc_subscrp_cancel() was
executed to cancel a subscription, the subscription's subscriber
refcnt had been decreased to 1. After tipc_subscrp_delete() where
the subscriber was freed because its refcnt was decremented to zero,
but the subscriber's lock had to be released, as a consequence, panic
happened.

By contrast, if we increase subscriber's refcnt before
tipc_subscrb_subscrp_delete() is called in tipc_subscrp_cancel(),
the panic issue can be avoided.

Fixes: d094c4d5f5c7 ("tipc: add subscription refcount to avoid invalid delete")
Reported-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: remove subscription references only for pending timers 2017-08-22T21:25:02+00:00 Parthasarathy Bhuvaragan parthasarathy.bhuvaragan@ericsson.com 2017-08-22T10:28:40+00:00 458be024ef5f72f1697d5d55289c4ed45f8ee910 In commit, 139bb36f754a ("tipc: advance the time of deleting subscription from subscriber->subscrp_list"), we delete the subscription from the subscribers list and from nametable unconditionally. This leads to the following bug if the timer running tipc_subscrp_timeout() in another CPU accesses the subscription list after the subscription delete request. [39.570] general protection fault: 0000 [#1] SMP :: [39.574] task: ffffffff81c10540 task.stack: ffffffff81c00000 [39.575] RIP: 0010:tipc_subscrp_timeout+0x32/0x80 [tipc] [39.576] RSP: 0018:ffff88003ba03e90 EFLAGS: 00010282 [39.576] RAX: dead000000000200 RBX: ffff88003f0f3600 RCX: 0000000000000101 [39.577] RDX: dead000000000100 RSI: 0000000000000201 RDI: ffff88003f0d7948 [39.578] RBP: ffff88003ba03ea0 R08: 0000000000000001 R09: ffff88003ba03ef8 [39.579] R10: 000000000000014f R11: 0000000000000000 R12: ffff88003f0d7948 [39.580] R13: ffff88003f0f3618 R14: ffffffffa006c250 R15: ffff88003f0f3600 [39.581] FS: 0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000 [39.582] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [39.583] CR2: 00007f831c6e0714 CR3: 000000003d3b0000 CR4: 00000000000006f0 [39.584] Call Trace: [39.584] <IRQ> [39.585] call_timer_fn+0x3d/0x180 [39.585] ? tipc_subscrb_rcv_cb+0x260/0x260 [tipc] [39.586] run_timer_softirq+0x168/0x1f0 [39.586] ? sched_clock_cpu+0x16/0xc0 [39.587] __do_softirq+0x9b/0x2de [39.587] irq_exit+0x60/0x70 [39.588] smp_apic_timer_interrupt+0x3d/0x50 [39.588] apic_timer_interrupt+0x86/0x90 [39.589] RIP: 0010:default_idle+0x20/0xf0 [39.589] RSP: 0018:ffffffff81c03e58 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 [39.590] RAX: 0000000000000000 RBX: ffffffff81c10540 RCX: 0000000000000000 [39.591] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [39.592] RBP: ffffffff81c03e68 R08: 0000000000000000 R09: 0000000000000000 [39.593] R10: ffffc90001cbbe00 R11: 0000000000000000 R12: 0000000000000000 [39.594] R13: ffffffff81c10540 R14: 0000000000000000 R15: 0000000000000000 [39.595] </IRQ> :: [39.603] RIP: tipc_subscrp_timeout+0x32/0x80 [tipc] RSP: ffff88003ba03e90 [39.604] ---[ end trace 79ce94b7216cb459 ]--- Fixes: 139bb36f754a ("tipc: advance the time of deleting subscription from subscriber->subscrp_list") Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
In commit, 139bb36f754a ("tipc: advance the time of deleting
subscription from subscriber->subscrp_list"), we delete the
subscription from the subscribers list and from nametable
unconditionally. This leads to the following bug if the timer
running tipc_subscrp_timeout() in another CPU accesses the
subscription list after the subscription delete request.

[39.570] general protection fault: 0000 [#1] SMP
::
[39.574] task: ffffffff81c10540 task.stack: ffffffff81c00000
[39.575] RIP: 0010:tipc_subscrp_timeout+0x32/0x80 [tipc]
[39.576] RSP: 0018:ffff88003ba03e90 EFLAGS: 00010282
[39.576] RAX: dead000000000200 RBX: ffff88003f0f3600 RCX: 0000000000000101
[39.577] RDX: dead000000000100 RSI: 0000000000000201 RDI: ffff88003f0d7948
[39.578] RBP: ffff88003ba03ea0 R08: 0000000000000001 R09: ffff88003ba03ef8
[39.579] R10: 000000000000014f R11: 0000000000000000 R12: ffff88003f0d7948
[39.580] R13: ffff88003f0f3618 R14: ffffffffa006c250 R15: ffff88003f0f3600
[39.581] FS:  0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000
[39.582] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39.583] CR2: 00007f831c6e0714 CR3: 000000003d3b0000 CR4: 00000000000006f0
[39.584] Call Trace:
[39.584]  <IRQ>
[39.585]  call_timer_fn+0x3d/0x180
[39.585]  ? tipc_subscrb_rcv_cb+0x260/0x260 [tipc]
[39.586]  run_timer_softirq+0x168/0x1f0
[39.586]  ? sched_clock_cpu+0x16/0xc0
[39.587]  __do_softirq+0x9b/0x2de
[39.587]  irq_exit+0x60/0x70
[39.588]  smp_apic_timer_interrupt+0x3d/0x50
[39.588]  apic_timer_interrupt+0x86/0x90
[39.589] RIP: 0010:default_idle+0x20/0xf0
[39.589] RSP: 0018:ffffffff81c03e58 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
[39.590] RAX: 0000000000000000 RBX: ffffffff81c10540 RCX: 0000000000000000
[39.591] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[39.592] RBP: ffffffff81c03e68 R08: 0000000000000000 R09: 0000000000000000
[39.593] R10: ffffc90001cbbe00 R11: 0000000000000000 R12: 0000000000000000
[39.594] R13: ffffffff81c10540 R14: 0000000000000000 R15: 0000000000000000
[39.595]  </IRQ>
::
[39.603] RIP: tipc_subscrp_timeout+0x32/0x80 [tipc] RSP: ffff88003ba03e90
[39.604] ---[ end trace 79ce94b7216cb459 ]---

Fixes: 139bb36f754a ("tipc: advance the time of deleting subscription from subscriber->subscrp_list")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: fix use-after-free 2017-08-18T22:59:29+00:00 Eric Dumazet edumazet@google.com 2017-08-16T16:41:54+00:00 5bfd37b4de5c98e86b12bd13be5aa46c7484a125 syszkaller reported use-after-free in tipc [1] When msg->rep skb is freed, set the pointer to NULL, so that caller does not free it again. [1] ================================================================== BUG: KASAN: use-after-free in skb_push+0xd4/0xe0 net/core/skbuff.c:1466 Read of size 8 at addr ffff8801c6e71e90 by task syz-executor5/4115 CPU: 1 PID: 4115 Comm: syz-executor5 Not tainted 4.13.0-rc4+ #32 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 skb_push+0xd4/0xe0 net/core/skbuff.c:1466 tipc_nl_compat_recv+0x833/0x18f0 net/tipc/netlink_compat.c:1209 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:898 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4512e9 RSP: 002b:00007f3bc8184c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004512e9 RDX: 0000000000000020 RSI: 0000000020fdb000 RDI: 0000000000000006 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b5e76 R13: 00007f3bc8184b48 R14: 00000000004b5e86 R15: 0000000000000000 Allocated by task 4115: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc_node+0x13d/0x750 mm/slab.c:3651 __alloc_skb+0xf1/0x740 net/core/skbuff.c:219 alloc_skb include/linux/skbuff.h:903 [inline] tipc_tlv_alloc+0x26/0xb0 net/tipc/netlink_compat.c:148 tipc_nl_compat_dumpit+0xf2/0x3c0 net/tipc/netlink_compat.c:248 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline] tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:898 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 4115: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x77/0x280 mm/slab.c:3763 kfree_skbmem+0x1a1/0x1d0 net/core/skbuff.c:622 __kfree_skb net/core/skbuff.c:682 [inline] kfree_skb+0x165/0x4c0 net/core/skbuff.c:699 tipc_nl_compat_dumpit+0x36a/0x3c0 net/tipc/netlink_compat.c:260 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline] tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline] netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 sock_write_iter+0x31a/0x5d0 net/socket.c:898 call_write_iter include/linux/fs.h:1743 [inline] new_sync_write fs/read_write.c:457 [inline] __vfs_write+0x684/0x970 fs/read_write.c:470 vfs_write+0x189/0x510 fs/read_write.c:518 SYSC_write fs/read_write.c:565 [inline] SyS_write+0xef/0x220 fs/read_write.c:557 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801c6e71dc0 which belongs to the cache skbuff_head_cache of size 224 The buggy address is located 208 bytes inside of 224-byte region [ffff8801c6e71dc0, ffff8801c6e71ea0) The buggy address belongs to the page: page:ffffea00071b9c40 count:1 mapcount:0 mapping:ffff8801c6e71000 index:0x0 flags: 0x200000000000100(slab) raw: 0200000000000100 ffff8801c6e71000 0000000000000000 000000010000000c raw: ffffea0007224a20 ffff8801d98caf48 ffff8801d9e79040 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c6e71d80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801c6e71e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c6e71e80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801c6e71f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801c6e71f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Jon Maloy <jon.maloy@ericsson.com> Cc: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
syszkaller reported use-after-free in tipc [1]

When msg->rep skb is freed, set the pointer to NULL,
so that caller does not free it again.

[1]

==================================================================
BUG: KASAN: use-after-free in skb_push+0xd4/0xe0 net/core/skbuff.c:1466
Read of size 8 at addr ffff8801c6e71e90 by task syz-executor5/4115

CPU: 1 PID: 4115 Comm: syz-executor5 Not tainted 4.13.0-rc4+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x24e/0x340 mm/kasan/report.c:409
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 skb_push+0xd4/0xe0 net/core/skbuff.c:1466
 tipc_nl_compat_recv+0x833/0x18f0 net/tipc/netlink_compat.c:1209
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512e9
RSP: 002b:00007f3bc8184c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004512e9
RDX: 0000000000000020 RSI: 0000000020fdb000 RDI: 0000000000000006
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b5e76
R13: 00007f3bc8184b48 R14: 00000000004b5e86 R15: 0000000000000000

Allocated by task 4115:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc_node+0x13d/0x750 mm/slab.c:3651
 __alloc_skb+0xf1/0x740 net/core/skbuff.c:219
 alloc_skb include/linux/skbuff.h:903 [inline]
 tipc_tlv_alloc+0x26/0xb0 net/tipc/netlink_compat.c:148
 tipc_nl_compat_dumpit+0xf2/0x3c0 net/tipc/netlink_compat.c:248
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline]
 tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 4115:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x77/0x280 mm/slab.c:3763
 kfree_skbmem+0x1a1/0x1d0 net/core/skbuff.c:622
 __kfree_skb net/core/skbuff.c:682 [inline]
 kfree_skb+0x165/0x4c0 net/core/skbuff.c:699
 tipc_nl_compat_dumpit+0x36a/0x3c0 net/tipc/netlink_compat.c:260
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline]
 tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe

The buggy address belongs to the object at ffff8801c6e71dc0
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 208 bytes inside of
 224-byte region [ffff8801c6e71dc0, ffff8801c6e71ea0)
The buggy address belongs to the page:
page:ffffea00071b9c40 count:1 mapcount:0 mapping:ffff8801c6e71000 index:0x0
flags: 0x200000000000100(slab)
raw: 0200000000000100 ffff8801c6e71000 0000000000000000 000000010000000c
raw: ffffea0007224a20 ffff8801d98caf48 ffff8801d9e79040 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c6e71d80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8801c6e71e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c6e71e80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8801c6e71f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c6e71f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov  <dvyukov@google.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: avoid inheriting msg_non_seq flag when message is returned 2017-08-14T18:20:36+00:00 Jon Paul Maloy jon.maloy@ericsson.com 2017-08-14T16:28:49+00:00 59a361bc6f6e91d57f25ff0aebb0e646beb3b41d In the function msg_reverse(), we reverse the header while trying to reuse the original buffer whenever possible. Those rejected/returned messages are always transmitted as unicast, but the msg_non_seq field is not explicitly set to zero as it should be. We have seen cases where multicast senders set the message type to "NOT dest_droppable", meaning that a multicast message shorter than one MTU will be returned, e.g., during receive buffer overflow, by reusing the original buffer. This has the effect that even the 'msg_non_seq' field is inadvertently inherited by the rejected message, although it is now sent as a unicast message. This again leads the receiving unicast link endpoint to steer the packet toward the broadcast link receive function, where it is dropped. The affected unicast link is thereafter (after 100 failed retransmissions) declared 'stale' and reset. We fix this by unconditionally setting the 'msg_non_seq' flag to zero for all rejected/returned messages. Reported-by: Canh Duc Luu <canh.d.luu@dektech.com.au> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
In the function msg_reverse(), we reverse the header while trying to
reuse the original buffer whenever possible. Those rejected/returned
messages are always transmitted as unicast, but the msg_non_seq field
is not explicitly set to zero as it should be.

We have seen cases where multicast senders set the message type to
"NOT dest_droppable", meaning that a multicast message shorter than
one MTU will be returned, e.g., during receive buffer overflow, by
reusing the original buffer. This has the effect that even the
'msg_non_seq' field is inadvertently inherited by the rejected message,
although it is now sent as a unicast message. This again leads the
receiving unicast link endpoint to steer the packet toward the broadcast
link receive function, where it is dropped. The affected unicast link is
thereafter (after 100 failed retransmissions) declared 'stale' and
reset.

We fix this by unconditionally setting the 'msg_non_seq' flag to zero
for all rejected/returned messages.

Reported-by: Canh Duc Luu <canh.d.luu@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tipc: accept PACKET_MULTICAST packets 2017-08-14T18:19:25+00:00 Jon Paul Maloy jon.maloy@ericsson.com 2017-08-14T15:55:56+00:00 fed5f5718c4989a03b1b4cdc0c7f273c3c74ee9e On L2 bearers, the TIPC broadcast function is sending out packets using the corresponding L2 broadcast address. At reception, we filter such packets under the assumption that they will also be delivered as broadcast packets. This assumption doesn't always hold true. Under high load, we have seen that a switch may convert the destination address and deliver the packet as a PACKET_MULTICAST, something leading to inadvertently dropped packets and a stale and reset broadcast link. We fix this by extending the reception filtering to accept packets of type PACKET_MULTICAST. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
On L2 bearers, the TIPC broadcast function is sending out packets using
the corresponding L2 broadcast address. At reception, we filter such
packets under the assumption that they will also be delivered as
broadcast packets.

This assumption doesn't always hold true. Under high load, we have seen
that a switch may convert the destination address and deliver the packet
as a PACKET_MULTICAST, something leading to inadvertently dropped
packets and a stale and reset broadcast link.

We fix this by extending the reception filtering to accept packets of
type PACKET_MULTICAST.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>