From: Eric Dumazet <eric.dumazet@gmail.com>
To: syzbot <syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com>,
davem@davemloft.net, jhs@mojatatu.com, jiri@resnulli.us,
kuba@kernel.org, linux-kernel@vger.kernel.org,
netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com,
xiyou.wangcong@gmail.com, Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [syzbot] general protection fault in fq_codel_enqueue (3)
Date: Fri, 29 Oct 2021 08:59:44 -0700 [thread overview]
Message-ID: <67075233-6110-dd44-c69f-eddc2e6f3d82@gmail.com> (raw)
In-Reply-To: <000000000000c3a2af05cf7fda31@google.com>
On 10/29/21 8:55 AM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 1fc596a56b33 Merge tag 'trace-v5.15-rc6' of git://git.kern..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1453dc04b00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=b160d0631c7a8f26
> dashboard link: https://syzkaller.appspot.com/bug?extid=7a12909485b94426aceb
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=154a0b64b00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=177eec86b00000
>
> Bisection is inconclusive: the issue happens on the oldest tested release.
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=154fc86ab00000
> final oops: https://syzkaller.appspot.com/x/report.txt?x=174fc86ab00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=134fc86ab00000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7a12909485b94426aceb@syzkaller.appspotmail.com
>
> general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
> KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
> CPU: 1 PID: 6542 Comm: syz-executor965 Not tainted 5.15.0-rc7-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline]
> RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
> RIP: 0010:fq_codel_enqueue+0x83e/0x10c0 net/sched/sch_fq_codel.c:230
> Code: f8 e2 25 fa 45 39 ec 0f 83 cb 00 00 00 e8 1a dc 25 fa 48 8b 44 24 10 80 38 00 0f 85 9a 06 00 00 49 8b 07 48 89 c2 48 c1 ea 03 <42> 80 3c 32 00 0f 85 6e 06 00 00 48 8b 10 48 8d 78 28 49 89 17 48
> RSP: 0018:ffffc90001187310 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff87504776 RDI: 0000000000000003
> RBP: ffffc900011874e0 R08: 0000000000000400 R09: 0000000000000001
> R10: ffffffff875046d6 R11: 0000000000000000 R12: 0000000000000400
> R13: 0000000000000000 R14: dffffc0000000000 R15: ffff888071660000
> FS: 0000555556b21300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f9c09885040 CR3: 0000000021c77000 CR4: 00000000003506e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3771
> __dev_xmit_skb net/core/dev.c:3855 [inline]
> __dev_queue_xmit+0x1f0e/0x36e0 net/core/dev.c:4170
> __bpf_tx_skb net/core/filter.c:2114 [inline]
> __bpf_redirect_no_mac net/core/filter.c:2139 [inline]
> __bpf_redirect+0x5ba/0xd20 net/core/filter.c:2162
> ____bpf_clone_redirect net/core/filter.c:2429 [inline]
> bpf_clone_redirect+0x2ae/0x420 net/core/filter.c:2401
> ___bpf_prog_run+0x3592/0x77d0 kernel/bpf/core.c:1548
> __bpf_prog_run512+0x91/0xd0 kernel/bpf/core.c:1776
> bpf_dispatcher_nop_func include/linux/bpf.h:718 [inline]
> __bpf_prog_run include/linux/filter.h:624 [inline]
> bpf_prog_run include/linux/filter.h:631 [inline]
> bpf_test_run+0x37c/0xa20 net/bpf/test_run.c:119
> bpf_prog_test_run_skb+0xa7c/0x1cb0 net/bpf/test_run.c:662
> bpf_prog_test_run kernel/bpf/syscall.c:3307 [inline]
> __sys_bpf+0x2137/0x5df0 kernel/bpf/syscall.c:4605
> __do_sys_bpf kernel/bpf/syscall.c:4691 [inline]
> __se_sys_bpf kernel/bpf/syscall.c:4689 [inline]
> __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4689
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x44/0xae
> RIP: 0033:0x7fef7c1e24d9
> Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffc95c98158 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fef7c1e24d9
> RDX: 0000000000000048 RSI: 0000000020000140 RDI: 000000000000000a
> RBP: 00007fef7c1a64c0 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007fef7c1a6550
> R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> Modules linked in:
> ---[ end trace 0597f54336b28fa4 ]---
> RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline]
> RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline]
> RIP: 0010:fq_codel_enqueue+0x83e/0x10c0 net/sched/sch_fq_codel.c:230
> Code: f8 e2 25 fa 45 39 ec 0f 83 cb 00 00 00 e8 1a dc 25 fa 48 8b 44 24 10 80 38 00 0f 85 9a 06 00 00 49 8b 07 48 89 c2 48 c1 ea 03 <42> 80 3c 32 00 0f 85 6e 06 00 00 48 8b 10 48 8d 78 28 49 89 17 48
> RSP: 0018:ffffc90001187310 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff87504776 RDI: 0000000000000003
> RBP: ffffc900011874e0 R08: 0000000000000400 R09: 0000000000000001
> R10: ffffffff875046d6 R11: 0000000000000000 R12: 0000000000000400
> R13: 0000000000000000 R14: dffffc0000000000 R15: ffff888071660000
> FS: 0000555556b21300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f9c09885040 CR3: 0000000021c77000 CR4: 00000000003506e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> ----------------
> Code disassembly (best guess):
> 0: f8 clc
> 1: e2 25 loop 0x28
> 3: fa cli
> 4: 45 39 ec cmp %r13d,%r12d
> 7: 0f 83 cb 00 00 00 jae 0xd8
> d: e8 1a dc 25 fa callq 0xfa25dc2c
> 12: 48 8b 44 24 10 mov 0x10(%rsp),%rax
> 17: 80 38 00 cmpb $0x0,(%rax)
> 1a: 0f 85 9a 06 00 00 jne 0x6ba
> 20: 49 8b 07 mov (%r15),%rax
> 23: 48 89 c2 mov %rax,%rdx
> 26: 48 c1 ea 03 shr $0x3,%rdx
> * 2a: 42 80 3c 32 00 cmpb $0x0,(%rdx,%r14,1) <-- trapping instruction
> 2f: 0f 85 6e 06 00 00 jne 0x6a3
> 35: 48 8b 10 mov (%rax),%rdx
> 38: 48 8d 78 28 lea 0x28(%rax),%rdi
> 3c: 49 89 17 mov %rdx,(%r15)
> 3f: 48 rex.W
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
> syzbot can test patches for this issue, for details see:
> https://goo.gl/tpsmEJ#testing-patches
>
This is the bug I mentioned in https://marc.info/?l=linux-netdev&m=163552087226957&w=2
prev parent reply other threads:[~2021-10-29 15:59 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-29 15:55 [syzbot] general protection fault in fq_codel_enqueue (3) syzbot
2021-10-29 15:59 ` Eric Dumazet [this message]
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