Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
CPU: 0 UID: 0 PID: 63 Comm: kworker/u8:4 Not tainted 6.15.0-rc4-syzkaller-00189-g2bfcee565c3a #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: netns cleanup_net
RIP: 0010:__fib6_drop_pcpu_from+0x1f0/0x3b0 net/ipv6/ip6_fib.c:980
Code: 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ef e8 57 ee 15 f8 49 8b 6d 00 48 85 ed 74 2f 48 81 c5 90 00 00 00 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 31 ee 15 f8 48 8b 45 00 48 3b 44
RSP: 0018:ffffc90001556e28 EFLAGS: 00010206
RAX: 0000000000000012 RBX: ffffffff8d958c10 RCX: ffff88801afe3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000091 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8a099eb6 R12: 0000000000000000
R13: ffffe8ffffc30f50 R14: dffffc0000000000 R15: ffff88805dab1110
FS:  0000000000000000(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe4964db26 CR3: 0000000063db4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1024 [inline]
 fib6_purge_rt+0x143/0x830 net/ipv6/ip6_fib.c:1035
 fib6_del_route net/ipv6/ip6_fib.c:1995 [inline]
 fib6_del+0xee1/0x1550 net/ipv6/ip6_fib.c:2040
 fib6_clean_node+0x29f/0x590 net/ipv6/ip6_fib.c:2202
 fib6_walk_continue+0x678/0x910 net/ipv6/ip6_fib.c:2124
 fib6_walk+0x149/0x290 net/ipv6/ip6_fib.c:2172
 fib6_clean_tree net/ipv6/ip6_fib.c:2252 [inline]
 __fib6_clean_all+0x234/0x380 net/ipv6/ip6_fib.c:2268
 rt6_sync_down_dev net/ipv6/route.c:4951 [inline]
 rt6_disable_ip+0x120/0x720 net/ipv6/route.c:4956
 addrconf_ifdown+0x15d/0x1880 net/ipv6/addrconf.c:3854
 addrconf_notify+0x1bc/0x1010 net/ipv6/addrconf.c:-1
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 dev_close_many+0x29c/0x410 net/core/dev.c:1731
 unregister_netdevice_many_notify+0x834/0x2330 net/core/dev.c:11952
 cleanup_net+0x6a3/0xbd0 net/core/net_namespace.c:649
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__fib6_drop_pcpu_from+0x1f0/0x3b0 net/ipv6/ip6_fib.c:980
Code: 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ef e8 57 ee 15 f8 49 8b 6d 00 48 85 ed 74 2f 48 81 c5 90 00 00 00 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 31 ee 15 f8 48 8b 45 00 48 3b 44
RSP: 0018:ffffc90001556e28 EFLAGS: 00010206
RAX: 0000000000000012 RBX: ffffffff8d958c10 RCX: ffff88801afe3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000091 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8a099eb6 R12: 0000000000000000
R13: ffffe8ffffc30f50 R14: dffffc0000000000 R15: ffff88805dab1110
FS:  0000000000000000(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe4964db26 CR3: 0000000063db4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 c1 e8 03          	shr    $0x3,%rax
   4:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
   9:	74 08                	je     0x13
   b:	4c 89 ef             	mov    %r13,%rdi
   e:	e8 57 ee 15 f8       	call   0xf815ee6a
  13:	49 8b 6d 00          	mov    0x0(%r13),%rbp
  17:	48 85 ed             	test   %rbp,%rbp
  1a:	74 2f                	je     0x4b
  1c:	48 81 c5 90 00 00 00 	add    $0x90,%rbp
  23:	48 89 e8             	mov    %rbp,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 ef             	mov    %rbp,%rdi
  34:	e8 31 ee 15 f8       	call   0xf815ee6a
  39:	48 8b 45 00          	mov    0x0(%rbp),%rax
  3d:	48                   	rex.W
  3e:	3b                   	.byte 0x3b
  3f:	44                   	rex.R