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lec:lec_vcc_attach: copy from user failed for 28 bytes
lec:lec_vcc_attach: copy from user failed for 28 bytes
lec:lec_vcc_attach: copy from user failed for 28 bytes
lec:lec_vcc_attach: copy from user failed for 28 bytes
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 12737 Comm: syz.3.1864 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:lec_arp_clear_vccs+0xad/0x380 net/atm/lec.c:1263
Code: e8 03 80 3c 28 00 74 08 4c 89 e7 e8 3d 1f 9c f7 4c 89 74 24 18 49 8b 2c 24 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 15 1f 9c f7 4d 8b 75 00 4d 8d a7 30
RSP: 0018:ffffc9001be4f9a8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff888055875000 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8bc08340 RDI: ffff888055875000
RBP: ffff88807b9b8000 R08: ffffffff8e6a8373 R09: 1ffffffff1cd506e
R10: dffffc0000000000 R11: fffffbfff1cd506f R12: ffff888140b12650
R13: 0000000000000000 R14: ffff888055875030 R15: ffff888140b12000
FS:  00007f3bcfe5d6c0(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e27bb42f8 CR3: 00000000298f6000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lec_vcc_close net/atm/lec.c:2183 [inline]
 lec_push+0x3cb/0x19f0 net/atm/lec.c:594
 vcc_destroy_socket net/atm/common.c:183 [inline]
 vcc_release+0x15f/0x580 net/atm/common.c:205
 __sock_release net/socket.c:662 [inline]
 sock_close+0xc3/0x240 net/socket.c:1455
 __fput+0x44c/0xa70 fs/file_table.c:468
 task_work_run+0x1d4/0x260 kernel/task_work.c:233
 get_signal+0x11ec/0x1340 kernel/signal.c:2807
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4e0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3bcef8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3bcfe5d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f3bcf1e5fa0 RCX: 00007f3bcef8f749
RDX: 0000000000000000 RSI: 00000000000061d1 RDI: 0000000000000004
RBP: 00007f3bcf013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3bcf1e6038 R14: 00007f3bcf1e5fa0 R15: 00007ffc1d22adb8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:lec_arp_clear_vccs+0xad/0x380 net/atm/lec.c:1263
Code: e8 03 80 3c 28 00 74 08 4c 89 e7 e8 3d 1f 9c f7 4c 89 74 24 18 49 8b 2c 24 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ef e8 15 1f 9c f7 4d 8b 75 00 4d 8d a7 30
RSP: 0018:ffffc9001be4f9a8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff888055875000 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8bc08340 RDI: ffff888055875000
RBP: ffff88807b9b8000 R08: ffffffff8e6a8373 R09: 1ffffffff1cd506e
R10: dffffc0000000000 R11: fffffbfff1cd506f R12: ffff888140b12650
R13: 0000000000000000 R14: ffff888055875030 R15: ffff888140b12000
FS:  00007f3bcfe5d6c0(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7e27bb42f8 CR3: 00000000298f6000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	e8 03 80 3c 28       	call   0x283c8008
   5:	00 74 08 4c          	add    %dh,0x4c(%rax,%rcx,1)
   9:	89 e7                	mov    %esp,%edi
   b:	e8 3d 1f 9c f7       	call   0xf79c1f4d
  10:	4c 89 74 24 18       	mov    %r14,0x18(%rsp)
  15:	49 8b 2c 24          	mov    (%r12),%rbp
  19:	4c 89 e8             	mov    %r13,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 ef             	mov    %r13,%rdi
  33:	e8 15 1f 9c f7       	call   0xf79c1f4d
  38:	4d 8b 75 00          	mov    0x0(%r13),%r14
  3c:	4d                   	rex.WRB
  3d:	8d                   	.byte 0x8d
  3e:	a7                   	cmpsl  %es:(%rdi),%ds:(%rsi)
  3f:	30                   	.byte 0x30