-
由 Erik Hugne 提交于
When link statistics is dumped over netlink, we iterate over the list of peer nodes and append each links statistics to the netlink msg. In the case where the dump is resumed after filling up a nlmsg, the node refcnt is decremented without having been incremented previously which may cause the node reference to be freed. When this happens, the following info/stacktrace will be generated, followed by a crash or undefined behavior. We fix this by removing the erroneous call to tipc_node_put inside the loop that iterates over nodes. [ 384.312303] INFO: trying to register non-static key. [ 384.313110] the code is fine but needs lockdep annotation. [ 384.313290] turning off the locking correctness validator. [ 384.313290] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.0.0+ #13 [ 384.313290] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 384.313290] ffff88003c6d0290 ffff88003cc03ca8 ffffffff8170adf1 0000000000000007 [ 384.313290] ffffffff82728730 ffff88003cc03d38 ffffffff810a6a6d 00000000001d7200 [ 384.313290] ffff88003c6d0ab0 ffff88003cc03ce8 0000000000000285 0000000000000001 [ 384.313290] Call Trace: [ 384.313290] <IRQ> [<ffffffff8170adf1>] dump_stack+0x4c/0x65 [ 384.313290] [<ffffffff810a6a6d>] __lock_acquire+0xf3d/0xf50 [ 384.313290] [<ffffffff810a7375>] lock_acquire+0xd5/0x290 [ 384.313290] [<ffffffffa0043e8c>] ? link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffffa0043e70>] ? link_state_event+0x4e0/0x4e0 [tipc] [ 384.313290] [<ffffffff81712890>] _raw_spin_lock_bh+0x40/0x80 [ 384.313290] [<ffffffffa0043e8c>] ? link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffffa0043e8c>] link_timeout+0x1c/0x170 [tipc] [ 384.313290] [<ffffffff810c4698>] call_timer_fn+0xb8/0x490 [ 384.313290] [<ffffffff810c45e0>] ? process_timeout+0x10/0x10 [ 384.313290] [<ffffffff810c5a2c>] run_timer_softirq+0x21c/0x420 [ 384.313290] [<ffffffffa0043e70>] ? link_state_event+0x4e0/0x4e0 [tipc] [ 384.313290] [<ffffffff8105a954>] __do_softirq+0xf4/0x630 [ 384.313290] [<ffffffff8105afdd>] irq_exit+0x5d/0x60 [ 384.313290] [<ffffffff8103ade1>] smp_apic_timer_interrupt+0x41/0x50 [ 384.313290] [<ffffffff817144a0>] apic_timer_interrupt+0x70/0x80 [ 384.313290] <EOI> [<ffffffff8100db10>] ? default_idle+0x20/0x210 [ 384.313290] [<ffffffff8100db0e>] ? default_idle+0x1e/0x210 [ 384.313290] [<ffffffff8100e61a>] arch_cpu_idle+0xa/0x10 [ 384.313290] [<ffffffff81099803>] cpu_startup_entry+0x2c3/0x530 [ 384.313290] [<ffffffff810d2893>] ? clockevents_register_device+0x113/0x200 [ 384.313290] [<ffffffff81038b0f>] start_secondary+0x13f/0x170 Fixes: 8a0f6ebe ("tipc: involve reference counter for node structure") Signed-off-by: NErik Hugne <erik.hugne@ericsson.com> Signed-off-by: NJon Maloy <jon.maloy@ericsson.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
73a31737