mirror of https://gitee.com/openkylin/linux.git
2cf750704b
Since the commit below the ipmr/ip6mr rtnl_unicast() code uses the portid
instead of the previous dst_pid which was copied from in_skb's portid.
Since the skb is new the portid is 0 at that point so the packets are sent
to the kernel and we get scheduling while atomic or a deadlock (depending
on where it happens) by trying to acquire rtnl two times.
Also since this is RTM_GETROUTE, it can be triggered by a normal user.
Here's the sleeping while atomic trace:
[ 7858.212557] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
[ 7858.212748] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/0
[ 7858.212881] 2 locks held by swapper/0/0:
[ 7858.213013] #0: (((&mrt->ipmr_expire_timer))){+.-...}, at: [<ffffffff810fbbf5>] call_timer_fn+0x5/0x350
[ 7858.213422] #1: (mfc_unres_lock){+.....}, at: [<ffffffff8161e005>] ipmr_expire_process+0x25/0x130
[ 7858.213807] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.0-rc7+ #179
[ 7858.213934] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 7858.214108] 0000000000000000 ffff88005b403c50 ffffffff813a7804 0000000000000000
[ 7858.214412] ffffffff81a1338e ffff88005b403c78 ffffffff810a4a72 ffffffff81a1338e
[ 7858.214716] 000000000000026c 0000000000000000 ffff88005b403ca8 ffffffff810a4b9f
[ 7858.215251] Call Trace:
[ 7858.215412] <IRQ> [<ffffffff813a7804>] dump_stack+0x85/0xc1
[ 7858.215662] [<ffffffff810a4a72>] ___might_sleep+0x192/0x250
[ 7858.215868] [<ffffffff810a4b9f>] __might_sleep+0x6f/0x100
[ 7858.216072] [<ffffffff8165bea3>] mutex_lock_nested+0x33/0x4d0
[ 7858.216279] [<ffffffff815a7a5f>] ? netlink_lookup+0x25f/0x460
[ 7858.216487] [<ffffffff8157474b>] rtnetlink_rcv+0x1b/0x40
[ 7858.216687] [<ffffffff815a9a0c>] netlink_unicast+0x19c/0x260
[ 7858.216900] [<ffffffff81573c70>] rtnl_unicast+0x20/0x30
[ 7858.217128] [<ffffffff8161cd39>] ipmr_destroy_unres+0xa9/0xf0
[ 7858.217351] [<ffffffff8161e06f>] ipmr_expire_process+0x8f/0x130
[ 7858.217581] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217785] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217990] [<ffffffff810fbc95>] call_timer_fn+0xa5/0x350
[ 7858.218192] [<ffffffff810fbbf5>] ? call_timer_fn+0x5/0x350
[ 7858.218415] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.218656] [<ffffffff810fde10>] run_timer_softirq+0x260/0x640
[ 7858.218865] [<ffffffff8166379b>] ? __do_softirq+0xbb/0x54f
[ 7858.219068] [<ffffffff816637c8>] __do_softirq+0xe8/0x54f
[ 7858.219269] [<ffffffff8107a948>] irq_exit+0xb8/0xc0
[ 7858.219463] [<ffffffff81663452>] smp_apic_timer_interrupt+0x42/0x50
[ 7858.219678] [<ffffffff816625bc>] apic_timer_interrupt+0x8c/0xa0
[ 7858.219897] <EOI> [<ffffffff81055f16>] ? native_safe_halt+0x6/0x10
[ 7858.220165] [<ffffffff810d64dd>] ? trace_hardirqs_on+0xd/0x10
[ 7858.220373] [<ffffffff810298e3>] default_idle+0x23/0x190
[ 7858.220574] [<ffffffff8102a20f>] arch_cpu_idle+0xf/0x20
[ 7858.220790] [<ffffffff810c9f8c>] default_idle_call+0x4c/0x60
[ 7858.221016] [<ffffffff810ca33b>] cpu_startup_entry+0x39b/0x4d0
[ 7858.221257] [<ffffffff8164f995>] rest_init+0x135/0x140
[ 7858.221469] [<ffffffff81f83014>] start_kernel+0x50e/0x51b
[ 7858.221670] [<ffffffff81f82120>] ? early_idt_handler_array+0x120/0x120
[ 7858.221894] [<ffffffff81f8243f>] x86_64_start_reservations+0x2a/0x2c
[ 7858.222113] [<ffffffff81f8257c>] x86_64_start_kernel+0x13b/0x14a
Fixes:
|
||
|---|---|---|
| .. | ||
| ila | ||
| netfilter | ||
| Kconfig | ||
| Makefile | ||
| addrconf.c | ||
| addrconf_core.c | ||
| addrlabel.c | ||
| af_inet6.c | ||
| ah6.c | ||
| anycast.c | ||
| calipso.c | ||
| datagram.c | ||
| esp6.c | ||
| exthdrs.c | ||
| exthdrs_core.c | ||
| exthdrs_offload.c | ||
| fib6_rules.c | ||
| fou6.c | ||
| icmp.c | ||
| inet6_connection_sock.c | ||
| inet6_hashtables.c | ||
| ip6_checksum.c | ||
| ip6_fib.c | ||
| ip6_flowlabel.c | ||
| ip6_gre.c | ||
| ip6_icmp.c | ||
| ip6_input.c | ||
| ip6_offload.c | ||
| ip6_offload.h | ||
| ip6_output.c | ||
| ip6_tunnel.c | ||
| ip6_udp_tunnel.c | ||
| ip6_vti.c | ||
| ip6mr.c | ||
| ipcomp6.c | ||
| ipv6_sockglue.c | ||
| mcast.c | ||
| mcast_snoop.c | ||
| mip6.c | ||
| ndisc.c | ||
| netfilter.c | ||
| output_core.c | ||
| ping.c | ||
| proc.c | ||
| protocol.c | ||
| raw.c | ||
| reassembly.c | ||
| route.c | ||
| sit.c | ||
| syncookies.c | ||
| sysctl_net_ipv6.c | ||
| tcp_ipv6.c | ||
| tcpv6_offload.c | ||
| tunnel6.c | ||
| udp.c | ||
| udp_impl.h | ||
| udp_offload.c | ||
| udplite.c | ||
| xfrm6_input.c | ||
| xfrm6_mode_beet.c | ||
| xfrm6_mode_ro.c | ||
| xfrm6_mode_transport.c | ||
| xfrm6_mode_tunnel.c | ||
| xfrm6_output.c | ||
| xfrm6_policy.c | ||
| xfrm6_protocol.c | ||
| xfrm6_state.c | ||
| xfrm6_tunnel.c | ||