general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 0 PID: 31235 Comm: syz-executor.5 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:pcpu_get_page_chunk mm/percpu.c:267 [inline]
RIP: 0010:pcpu_chunk_addr_search mm/percpu.c:1626 [inline]
RIP: 0010:free_percpu mm/percpu.c:2285 [inline]
RIP: 0010:free_percpu+0x182/0x10b0 mm/percpu.c:2268
Code: 80 3c 02 00 0f 85 8e 0e 00 00 48 8b 3b 48 01 ef e8 c3 1f 0a 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 20 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 36 0e 00 00 48 8b 58 20 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc9000233fc18 EFLAGS: 00010002
RAX: 0000000000000000 RBX: ffff88823ffe3c00 RCX: 0000000000000004
RDX: dffffc0000000000 RSI: ffffffff81afee9f RDI: 0000000000000020
RBP: ffffe8ffff000000 R08: 0000000000000000 R09: 0000000000000003
R10: ffffffff81aff020 R11: 0000000000000002 R12: ffff8880b9c53000
R13: 0000607f45400000 R14: ffff88823ffe3a08 R15: 0000000000000003
FS:  00007fd2a4786700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e4bc2 CR3: 00000000208af000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 tun_free_netdev+0x78/0x140 drivers/net/tun.c:2203
 netdev_run_todo+0x6b4/0xa80 net/core/dev.c:10643
 __tun_chr_ioctl.isra.0+0x9c4/0x4270 drivers/net/tun.c:3297
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl fs/ioctl.c:1055 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055
 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: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd2a4786188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000005
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 00007ffdc74f728f R14: 00007fd2a4786300 R15: 0000000000022000
Modules linked in:
---[ end trace 98e0db4d47118eb9 ]---
RIP: 0010:pcpu_get_page_chunk mm/percpu.c:267 [inline]
RIP: 0010:pcpu_chunk_addr_search mm/percpu.c:1626 [inline]
RIP: 0010:free_percpu mm/percpu.c:2285 [inline]
RIP: 0010:free_percpu+0x182/0x10b0 mm/percpu.c:2268
Code: 80 3c 02 00 0f 85 8e 0e 00 00 48 8b 3b 48 01 ef e8 c3 1f 0a 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 20 48 89 f9 48 c1 e9 03 <80> 3c 11 00 0f 85 36 0e 00 00 48 8b 58 20 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc9000233fc18 EFLAGS: 00010002
RAX: 0000000000000000 RBX: ffff88823ffe3c00 RCX: 0000000000000004
RDX: dffffc0000000000 RSI: ffffffff81afee9f RDI: 0000000000000020
RBP: ffffe8ffff000000 R08: 0000000000000000 R09: 0000000000000003
R10: ffffffff81aff020 R11: 0000000000000002 R12: ffff8880b9c53000
R13: 0000607f45400000 R14: ffff88823ffe3a08 R15: 0000000000000003
FS:  00007fd2a4786700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e4bc2 CR3: 00000000208af000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
----------------
Code disassembly (best guess):
   0:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   4:	0f 85 8e 0e 00 00    	jne    0xe98
   a:	48 8b 3b             	mov    (%rbx),%rdi
   d:	48 01 ef             	add    %rbp,%rdi
  10:	e8 c3 1f 0a 00       	callq  0xa1fd8
  15:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  1c:	fc ff df
  1f:	48 8d 78 20          	lea    0x20(%rax),%rdi
  23:	48 89 f9             	mov    %rdi,%rcx
  26:	48 c1 e9 03          	shr    $0x3,%rcx
* 2a:	80 3c 11 00          	cmpb   $0x0,(%rcx,%rdx,1) <-- trapping instruction
  2e:	0f 85 36 0e 00 00    	jne    0xe6a
  34:	48 8b 58 20          	mov    0x20(%rax),%rbx
  38:	48                   	rex.W
  39:	b8 00 00 00 00       	mov    $0x0,%eax
  3e:	00 fc                	add    %bh,%ah