Re: next-20180605 - BUG in ipv6_add_addr

From: David Ahern
Date: Thu Jun 07 2018 - 19:49:22 EST


On 6/7/18 1:17 PM, valdis.kletnieks@xxxxxx wrote:
> Hit the following, after which my network connection was pretty much hosed
>
> This ring any bells? I don't have a reproducer for this, so bisecting is problematic....
>
> [ 1820.832682] BUG: unable to handle kernel NULL pointer dereference at 0000000000000209
> [ 1820.832728] RIP: 0010:ipv6_add_addr+0x280/0xd10
> [ 1820.832732] Code: 49 8b 1f 0f 84 6a 0a 00 00 48 85 db 0f 84 4e 0a 00 00 48 8b 03 48 8b 53 08 49 89 45 00 49 8b 47 10
> 49 89 55 08 48 85 c0 74 15 <48> 8b 50 08 48 8b 00 49 89 95 b8 01 00 00 49 89 85 b0 01 00 00 4c
> [ 1820.832847] RSP: 0018:ffffaa07c2fd7880 EFLAGS: 00010202
> [ 1820.832853] RAX: 0000000000000201 RBX: ffffaa07c2fd79b0 RCX: 0000000000000000
> [ 1820.832858] RDX: a4cfbfba2cbfa64c RSI: 0000000000000000 RDI: ffffffff8a8e9fa0
> [ 1820.832862] RBP: ffffaa07c2fd7920 R08: 000000000000017a R09: ffffffff8a555300
> [ 1820.832866] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888d18e71c00
> [ 1820.832871] R13: ffff888d0a9b1200 R14: 0000000000000000 R15: ffffaa07c2fd7980
> [ 1820.832876] FS: 00007faa51bdb800(0000) GS:ffff888d1d400000(0000) knlGS:0000000000000000
> [ 1820.832880] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 1820.832885] CR2: 0000000000000209 CR3: 000000021e8f8001 CR4: 00000000001606e0
> [ 1820.832888] Call Trace:
> [ 1820.832898] ? __local_bh_enable_ip+0x119/0x260
> [ 1820.832904] ? ipv6_create_tempaddr+0x259/0x5a0
> [ 1820.832912] ? __local_bh_enable_ip+0x139/0x260
> [ 1820.832921] ipv6_create_tempaddr+0x2da/0x5a0
> [ 1820.832926] ? ipv6_create_tempaddr+0x2da/0x5a0
> [ 1820.832941] manage_tempaddrs+0x1a5/0x240
> [ 1820.832951] inet6_addr_del+0x20b/0x3b0
> [ 1820.832959] ? nla_parse+0xce/0x1e0
> [ 1820.832968] inet6_rtm_deladdr+0xd9/0x210
> [ 1820.832981] rtnetlink_rcv_msg+0x1d4/0x5f0

I am the most likely guilty party. I have been staring at the code for
this stack trace for a while and nothing jumps out. Can you send me the
kernel config?