Re: [B.A.T.M.A.N.] kernel BUG at net/core/skbuff.c:100

Philipp Psurek
2014-11-24T22:26:13Z

[-- Attachment #1: Type: text/plain, Size: 9442 bytes --]

Hi all,

it's me again. There is another back-trace.

I can't help myself. Now I switch to 3.17.3 with your patch:

# cd net/batman-adv/
# patch < /usr/src/frag_debug_size.patch
patching file fragmentation.c
Hunk #1 succeeded at 250 (offset 1 line).
# cd /usr/src/linux
# make
CHK include/config/kernel.release
CHK include/generated/uapi/linux/version.h
CHK include/generated/utsrelease.h
CALL scripts/checksyscalls.sh
CHK include/generated/compile.h
CC [M] net/batman-adv/fragmentation.o
LD [M] net/batman-adv/batman-adv.o
Kernel: arch/x86/boot/bzImage is ready (#1)
Building modules, stage 2.
MODPOST 29 modules
CC net/batman-adv/batman-adv.mod.o
LD [M] net/batman-adv/batman-adv.ko
# make modules_install
[ … ]

3.17.4 compiles now for the next crash.

Best regards

Philipp

________________________
Freifunk Rheinland e. V.
– Funkzelle Wuppertal –

SYSTEM MAP: /boot/System.map
DEBUG KERNEL: /usr/src/linux-3.16.7-gentoo/vmlinux (3.16.7-gentoo)
DUMPFILE: vmcore_20141124222013
CPUS: 1
DATE: Mon Nov 24 22:15:06 2014
UPTIME: 00:46:49
LOAD AVERAGE: 0.14, 0.16, 0.14
TASKS: 137
NODENAME: wolke
RELEASE: 3.16.7-gentoo
VERSION: #1 SMP Mon Nov 17 03:44:22 CET 2014
MACHINE: x86_64 (2593 Mhz)
MEMORY: 511.6 MB
PANIC: "kernel BUG at net/core/skbuff.c:100!"
PID: 1971
COMMAND: "fastd"
TASK: ffff88001a31e0f0 [THREAD_INFO: ffff880019c5c000]
CPU: 0
STATE: TASK_RUNNING (PANIC)

crash> bt
PID: 1971 TASK: ffff88001a31e0f0 CPU: 0 COMMAND: "fastd"
#0 [ffff88001fc03980] machine_kexec at ffffffff8103a34e
#1 [ffff88001fc039e0] crash_kexec at ffffffff810be503
#2 [ffff88001fc03ab0] oops_end at ffffffff81005fc8
#3 [ffff88001fc03ae0] die at ffffffff81006463
#4 [ffff88001fc03b10] do_trap at ffffffff81002e12
#5 [ffff88001fc03b70] do_error_trap at ffffffff8100316d
#6 [ffff88001fc03c30] do_invalid_op at ffffffff8100394b
#7 [ffff88001fc03c40] invalid_op at ffffffff817f385e
[exception RIP: skb_panic+94]
RIP: ffffffff817eb99d RSP: ffff88001fc03cf8 RFLAGS: 00010296
RAX: 000000000000008b RBX: ffff8800057c9860 RCX: 0000000000000092
RDX: 000000000000003c RSI: 0000000000000046 RDI: 0000000000000246
RBP: ffff88001fc03d18 R8: 0000000000000000 R9: 0000000000000000
R10: 00000000000001a5 R11: 0000000000000006 R12: 0000000000000564
R13: ffff88001fc03da0 R14: ffff8800191def00 R15: ffff880019200062
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#8 [ffff88001fc03d20] skb_put at ffffffff81611bb1
#9 [ffff88001fc03d30] batadv_frag_skb_buffer at ffffffffa001be12 [batman_adv]
#10 [ffff88001fc03d90] batadv_recv_frag_packet at ffffffffa0026273 [batman_adv]
#11 [ffff88001fc03dd0] batadv_batman_skb_recv at ffffffffa001fef5 [batman_adv]
#12 [ffff88001fc03e10] __netif_receive_skb_core at ffffffff81621962
#13 [ffff88001fc03e80] __netif_receive_skb at ffffffff81621e91
#14 [ffff88001fc03ea0] process_backlog at ffffffff81621f7e
#15 [ffff88001fc03ef0] net_rx_action at ffffffff81622731
#16 [ffff88001fc03f50] __do_softirq at ffffffff81053ef8
#17 [ffff88001fc03fb0] do_softirq_own_stack at ffffffff817f3a5c
--- <IRQ stack> ---
#18 [ffff880019c5fd10] do_softirq_own_stack at ffffffff817f3a5c
[exception RIP: tun_get_user+1056]
RIP: ffffffffa00098f0 RSP: 0000000000000001 RFLAGS: 7fff00000586
RAX: ffffffff816210b4 RBX: ffff880019c5fd58 RCX: ffff8800192f0780
RDX: 0000000000000000 RSI: ffff8800192f0780 RDI: 0000000000000586
RBP: ffffffff81620de4 R8: ffff880019c5fd88 R9: ffff8800192f0780
R10: ffff8800192f0780 R11: ffffffff81054135 R12: ffff880019c5fd58
R13: 0000000000000586 R14: ffff8800191de000 R15: 0000000000000000
ORIG_RAX: ffff880019c5fe38 CS: 7fff4026c120 SS: 0000
bt: WARNING: possibly bogus exception frame
#19 [ffff880019c5fe40] tun_chr_aio_write at ffffffffa0009e0b [tun]
#20 [ffff880019c5fe70] do_sync_write at ffffffff8115c665
#21 [ffff880019c5ff00] vfs_write at ffffffff8115d38a
#22 [ffff880019c5ff40] sys_write at ffffffff8115d89a
#23 [ffff880019c5ff80] system_call_fastpath at ffffffff817f1f29
RIP: 00007fcaf8b9537d RSP: 00007fff4026c3a8 RFLAGS: 00010202
RAX: 0000000000000001 RBX: ffffffff817f1f29 RCX: 0000000000000084
RDX: 0000000000000586 RSI: 00000000013e2f00 RDI: 0000000000000009
RBP: 0000000000000586 R8: 00007fcaf8b7e400 R9: 00007fff4026b868
R10: 00007fff4026bfaf R11: 0000000000000293 R12: 00000000013d64d8
R13: 0000000000000001 R14: 00000000013e2ef0 R15: 00000000013c46e0
ORIG_RAX: 0000000000000001 CS: 0033 SS: 002b

crash> log
[ 81.953301] tun: Universal TUN/TAP device driver, 1.6
[ 81.953305] tun: (C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>
[ 83.183042] batman_adv: B.A.T.M.A.N. advanced 2014.3.0 (compatibility version 15) loaded
[ 83.444516] batman_adv: bat0: Adding interface: fastd0
[ 83.444520] batman_adv: bat0: The MTU of interface fastd0 is too small (1426) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
[ 83.444524] batman_adv: bat0: Interface activated: fastd0
[ 83.445515] batman_adv: bat0: orig_interval: Changing from: 1000 to: 5000
[ 83.446957] batman_adv: bat0: bridge_loop_avoidance: Changing from: disabled to: enabled
[ 83.447682] batman_adv: bat0: Changing gw mode from: off to: client
[ 132.723904] ipip: IPv4 over IPv4 tunneling driver
[ 188.931093] batman_adv: bat0: Changing gw mode from: client to: server
[ 188.931117] batman_adv: bat0: Changing gateway bandwidth from: '10.0/2.0 MBit' to: '100.0/100.0 MBit'
[ 317.574742] nf_conntrack: automatic helper assignment is deprecated and it will be removed soon. Use the iptables CT target to attach helpers instead.
[ 2809.763665] skbuff: skb_over_panic: text:ffffffffa001be12 len:1472 put:1380 head:ffff88000719b400 data:ffff88000719b462 tail:0x622 end:0x2c0 dev:fastd0
[ 2809.763978] ------------[ cut here ]------------
[ 2809.764097] kernel BUG at net/core/skbuff.c:100!
[ 2809.764195] invalid opcode: 0000 [#1] SMP
[ 2809.764297] Modules linked in: xt_nat iptable_nat nf_nat_ipv4 nf_nat ipip batman_adv libcrc32c tun crc32c_intel
[ 2809.764604] CPU: 0 PID: 1971 Comm: fastd Not tainted 3.16.7-gentoo #1
[ 2809.764604] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 2809.764604] task: ffff88001a31e0f0 ti: ffff880019c5c000 task.ti: ffff880019c5c000
[ 2809.764604] RIP: 0010:[<ffffffff817eb99d>] [<ffffffff817eb99d>] skb_panic+0x5e/0x60
[ 2809.764604] RSP: 0018:ffff88001fc03cf8 EFLAGS: 00010296
[ 2809.764604] RAX: 000000000000008b RBX: ffff8800057c9860 RCX: 0000000000000092
[ 2809.764604] RDX: 000000000000003c RSI: 0000000000000046 RDI: 0000000000000246
[ 2809.764604] RBP: ffff88001fc03d18 R08: 0000000000000000 R09: 0000000000000000
[ 2809.764604] R10: 00000000000001a5 R11: 0000000000000006 R12: 0000000000000564
[ 2809.764604] R13: ffff88001fc03da0 R14: ffff8800191def00 R15: ffff880019200062
[ 2809.764604] FS: 00007fcaf9841700(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[ 2809.764604] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2809.764604] CR2: 00007f0953452000 CR3: 00000000191da000 CR4: 00000000000006f0
[ 2809.764604] Stack:
[ 2809.764604] ffff88000719b462 0000000000000622 00000000000002c0 ffff8800192f0000
[ 2809.764604] ffff88001fc03d28 ffffffff81611bb1 ffff88001fc03d88 ffffffffa001be12
[ 2809.764604] ffff88001f33d168 ffff88001920004e ffff88001fc03d78 ffff8800057c9860
[ 2809.764604] Call Trace:
[ 2809.764604] <IRQ>
[ 2809.764604]
[ 2809.764604] [<ffffffff81611bb1>] skb_put+0x41/0x50
[ 2809.764604] [<ffffffffa001be12>] batadv_frag_skb_buffer+0x272/0x470 [batman_adv]
[ 2809.764604] [<ffffffffa0026273>] batadv_recv_frag_packet+0x183/0x200 [batman_adv]
[ 2809.764604] [<ffffffffa001fef5>] batadv_batman_skb_recv+0xd5/0x110 [batman_adv]
[ 2809.764604] [<ffffffff81621962>] __netif_receive_skb_core+0x222/0x730
[ 2809.764604] [<ffffffff81621e91>] __netif_receive_skb+0x21/0x70
[ 2809.764604] [<ffffffff81621f7e>] process_backlog+0x9e/0x170
[ 2809.764604] [<ffffffff81622731>] net_rx_action+0x141/0x240
[ 2809.764604] [<ffffffff81053ef8>] __do_softirq+0xe8/0x280
[ 2809.764604] [<ffffffff817f3a5c>] do_softirq_own_stack+0x1c/0x30
[ 2809.764604] <EOI>
[ 2809.764604]
[ 2809.764604] [<ffffffff81054135>] do_softirq+0x55/0x60
[ 2809.764604] [<ffffffff816210b4>] netif_rx_ni+0x34/0x70
[ 2809.764604] [<ffffffffa00098f0>] tun_get_user+0x420/0x840 [tun]
[ 2809.764604] [<ffffffffa0009e0b>] tun_chr_aio_write+0x7b/0xa0 [tun]
[ 2809.764604] [<ffffffff8115c665>] do_sync_write+0x55/0x90
[ 2809.764604] [<ffffffff8115d38a>] vfs_write+0xba/0x1f0
[ 2809.764604] [<ffffffff8115d89a>] SyS_write+0x4a/0xa0
[ 2809.764604] [<ffffffff817f1f29>] system_call_fastpath+0x16/0x1b
[ 2809.764604] Code: 00 00 48 89 44 24 10 8b 87 c0 00 00 00 48 89 44 24 08 48 8b 87 d0 00 00 00 48 c7 c7 30 67 a3 81 48 89 04 24 31 c0 e8 0d 8b ff ff <0f> 0b 55 48 89 f8 48 8b 57 30 48 89 e5 48 8b 0f 5d 80 e5 80 48
[ 2809.764604] RIP [<ffffffff817eb99d>] skb_panic+0x5e/0x60
[ 2809.764604] RSP <ffff88001fc03cf8>