general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 7351 Comm: syz.5.635 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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+0xd71/0x1600 net/sched/sch_fq_codel.c:230
Code: 24 08 48 8b 44 24 20 80 3c 10 00 74 12 4c 89 ef e8 24 cd ab f9 48 ba 00 00 00 00 00 fc ff df 4d 8b 65 00 4c 89 e0 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 e7 e8 01 cd ab f9 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc9000340f660 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff92000681f1c RCX: 1ffff110045e585a
RDX: dffffc0000000000 RSI: 0000000000000125 RDI: 0000000000000126
RBP: ffffc9000340f7b8 R08: ffffffff901d518f R09: 1ffffffff203aa31
R10: dffffc0000000000 R11: fffffbfff203aa32 R12: 0000000000000000
R13: ffff888022f2f800 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f3657b546c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3011eff8 CR3: 0000000018182000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
dev_qdisc_enqueue+0x48/0x210 net/core/dev.c:3865
__dev_xmit_skb net/core/dev.c:3949 [inline]
__dev_queue_xmit+0xc25/0x2f80 net/core/dev.c:4266
packet_snd net/packet/af_packet.c:3089 [inline]
packet_sendmsg+0x3dba/0x5060 net/packet/af_packet.c:3120
sock_sendmsg_nosec net/socket.c:706 [inline]
__sock_sendmsg net/socket.c:718 [inline]
__sys_sendto+0x46d/0x620 net/socket.c:2072
__do_sys_sendto net/socket.c:2084 [inline]
__se_sys_sendto net/socket.c:2080 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2080
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f36598fadd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3657b54028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3659b73fa0 RCX: 00007f36598fadd9
RDX: 000000000000000e RSI: 00002000000008c0 RDI: 0000000000000004
RBP: 00007f3659990d69 R08: 0000200000000140 R09: 0000000000000014
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3659b74038 R14: 00007f3659b73fa0 R15: 00007ffcd8e9f808
</TASK>
Modules linked in:
---[ end trace 244334a0216750d7 ]---
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+0xd71/0x1600 net/sched/sch_fq_codel.c:230
Code: 24 08 48 8b 44 24 20 80 3c 10 00 74 12 4c 89 ef e8 24 cd ab f9 48 ba 00 00 00 00 00 fc ff df 4d 8b 65 00 4c 89 e0 48 c1 e8 03 <80> 3c 10 00 74 12 4c 89 e7 e8 01 cd ab f9 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc9000340f660 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff92000681f1c RCX: 1ffff110045e585a
RDX: dffffc0000000000 RSI: 0000000000000125 RDI: 0000000000000126
RBP: ffffc9000340f7b8 R08: ffffffff901d518f R09: 1ffffffff203aa31
R10: dffffc0000000000 R11: fffffbfff203aa32 R12: 0000000000000000
R13: ffff888022f2f800 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f3657b546c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3011eff8 CR3: 0000000018182000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 24 08 and $0x8,%al
2: 48 8b 44 24 20 mov 0x20(%rsp),%rax
7: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1)
b: 74 12 je 0x1f
d: 4c 89 ef mov %r13,%rdi
10: e8 24 cd ab f9 call 0xf9abcd39
15: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
1c: fc ff df
1f: 4d 8b 65 00 mov 0x0(%r13),%r12
23: 4c 89 e0 mov %r12,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) <-- trapping instruction
2e: 74 12 je 0x42
30: 4c 89 e7 mov %r12,%rdi
33: e8 01 cd ab f9 call 0xf9abcd39
38: 48 rex.W
39: ba 00 00 00 00 mov $0x0,%edx
3e: 00 fc add %bh,%ah