[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAL4Wiirsyi8vvx1=joFM5F-Q6JvhTaSAvQ5Fs6mtJPzVkpYwCg@mail.gmail.com>
Date: Sat, 8 Dec 2012 18:04:17 -0800
From: Eric Dumazet <eric.dumazet@...il.com>
To: Dave Jones <davej@...hat.com>
Cc: netdev@...r.kernel.org
Subject: Re: GPF in ip6_dst_lookup_tail
On Fri, Dec 7, 2012 at 6:15 AM, Dave Jones <davej@...hat.com> wrote:
> I just hit this gpf in overnight testing.
>
> general protection fault: 0000 [#1] PREEMPT SMP
> Modules linked in: sctp libcrc32c ipt_ULOG fuse binfmt_misc nfnetlink nfc caif_socket caif phonet bluetooth rfkill can llc2 pppoe pppox ppp_generic slhc irda crc_ccitt rds af_key decnet rose x25 atm netrom appletalk ipx p8023 psnap p8022 llc ax25 nfsv3 nfs_acl nfs fscache lockd sunrpc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_conntrack nf_conntrack ip6table_filter ip6_tables usb_debug microcode serio_raw pcspkr i2c_piix4 i2c_core r8169 mii vhost_net tun macvtap macvlan kvm_amd kvm
> CPU 3
> Pid: 19371, comm: trinity-child3 Not tainted 3.7.0-rc8+ #6 Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H
> RIP: 0010:[<ffffffff815fe038>] [<ffffffff815fe038>] ip6_dst_lookup_tail+0xe8/0x200
> RSP: 0018:ffff880046277968 EFLAGS: 00010206
> RAX: 2000000000000011 RBX: 0000000000000000 RCX: 0000000000000000
> RDX: ffff880046277b00 RSI: ffff880070a6cd80 RDI: ffff8800bb22d000
> RBP: ffff8800462779f8 R08: 0000000000000001 R09: 0000000000000000
> R10: 0000000000000001 R11: 0000000000000000 R12: ffff880046277a10
> R13: ffff880046277b00 R14: ffff8800bb22d000 R15: ffffffff81cb40c0
> FS: 00007f0817b3f740(0000) GS:ffff88012b400000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000000004 CR3: 00000000a7dfb000 CR4: 00000000000007e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> Process trinity-child3 (pid: 19371, threadinfo ffff880046276000, task ffff880044dca450)
> Stack:
> ffff8800bb22d000 0000000000000002 0000000000000001 0000000000000000
> ffff880046277998 ffffffff81335b56 ffff8800462779b8 ffffffff81074cec
> 0000000000000001 ffff880070a6cd80 ffff8800462779f8 00000000ae4317df
> Call Trace:
> [<ffffffff81335b56>] ? __const_udelay+0x36/0x40
> [<ffffffff81074cec>] ? __rcu_read_unlock+0x5c/0xa0
> [<ffffffff81527945>] ? sk_dst_check+0x5/0x260
> [<ffffffff815fe3fb>] ip6_sk_dst_lookup_flow+0xcb/0x1b0
> [<ffffffff8161f45e>] udpv6_sendmsg+0x66e/0xb90
> [<ffffffff81335b56>] ? __const_udelay+0x36/0x40
> [<ffffffff81074cec>] ? __rcu_read_unlock+0x5c/0xa0
> [<ffffffff815bd4e4>] inet_sendmsg+0x114/0x230
> [<ffffffff815bd3d5>] ? inet_sendmsg+0x5/0x230
> [<ffffffff815261e9>] ? sock_update_classid+0xa9/0x2d0
> [<ffffffff81526270>] ? sock_update_classid+0x130/0x2d0
> [<ffffffff81520d1c>] sock_sendmsg+0xbc/0xf0
> [<ffffffff810b7ab2>] ? get_lock_stats+0x22/0x70
> [<ffffffff810bd037>] ? lock_release_non_nested+0x2b7/0x2f0
> [<ffffffff815210fc>] __sys_sendmsg+0x3ac/0x3c0
> [<ffffffff810b7b88>] ? trace_hardirqs_off_caller+0x28/0xc0
> [<ffffffff810b7ab2>] ? get_lock_stats+0x22/0x70
> [<ffffffff810b7f1e>] ? put_lock_stats.isra.23+0xe/0x40
> [<ffffffff8100a136>] ? native_sched_clock+0x26/0x90
> [<ffffffff810b7b88>] ? trace_hardirqs_off_caller+0x28/0xc0
> [<ffffffff81055e54>] ? do_setitimer+0x1c4/0x300
> [<ffffffff810b7f1e>] ? put_lock_stats.isra.23+0xe/0x40
> [<ffffffff811d6bea>] ? fget_light+0x3ca/0x500
> [<ffffffff810bdf9d>] ? trace_hardirqs_on+0xd/0x10
> [<ffffffff815237d9>] sys_sendmsg+0x49/0x90
> [<ffffffff81684b42>] system_call_fastpath+0x16/0x1b
> Code: 00 00 48 8b 5d d8 4c 8b 65 e0 4c 8b 6d e8 4c 8b 75 f0 4c 8b 7d f8 c9 c3 0f 1f 00 49 8b 34 24 48 8b 86 98 00 00 00 48 85 c0 74 c2 <f6> 80 6d 01 00 00 de 75 b9 48 8b 56 18 49 8d 75 24 b9 01 00 00
> RIP [<ffffffff815fe038>] ip6_dst_lookup_tail+0xe8/0x200
> RSP <ffff880046277968>
> ---[ end trace f7dde22e5674fdd6 ]---
>
>
>
> 0000000000000000 <.text>:
> 0: 00 00 add %al,(%rax)
> 2: 48 8b 5d d8 mov -0x28(%rbp),%rbx
> 6: 4c 8b 65 e0 mov -0x20(%rbp),%r12
> a: 4c 8b 6d e8 mov -0x18(%rbp),%r13
> e: 4c 8b 75 f0 mov -0x10(%rbp),%r14
> 12: 4c 8b 7d f8 mov -0x8(%rbp),%r15
> 16: c9 leaveq
> 17: c3 retq
> 18: 0f 1f 00 nopl (%rax)
> 1b: 49 8b 34 24 mov (%r12),%rsi
> 1f: 48 8b 86 98 00 00 00 mov 0x98(%rsi),%rax
> 26: 48 85 c0 test %rax,%rax
> 29: 74 c2 je 0xffffffffffffffed
>
> /home/davej/tmp/tmp.YOesIDyrIr.o: file format elf64-x86-64
>
>
> Disassembly of section .text:
>
> 0000000000000000 <.text>:
> 0: f6 80 6d 01 00 00 de testb $0xde,0x16d(%rax)
> 7: 75 b9 jne 0xffffffffffffffc2
> 9: 48 8b 56 18 mov 0x18(%rsi),%rdx
> d: 49 8d 75 24 lea 0x24(%r13),%rsi
> 11: b9 .byte 0xb9
> 12: 01 00 add %eax,(%rax)
> ...
>
>
> which looks like an inlined copy of ipv6_addr_any
>
> * marked as OPTIMISTIC, we release the found
> * dst entry and replace it instead with the
> * dst entry of the nexthop router
> */
> rt = (struct rt6_info *) *dst;
> n = rt->n;
> dc: 48 8b 86 98 00 00 00 mov 0x98(%rsi),%rax
> if (n && !(n->nud_state & NUD_VALID)) {
> e3: 48 85 c0 test %rax,%rax
> e6: 74 c2 je aa <ip6_dst_lookup_tail+0xaa>
> e8: f6 80 6d 01 00 00 de testb $0xde,0x16d(%rax)
> ef: 75 b9 jne aa <ip6_dst_lookup_tail+0xaa>
>
>
> RAX here is 2000000000000011 , which clearly isn't a valid rt address to dereference.
>
More exactly rt was fine, but n (rt->n) contains garbage
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists