syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc001fffe1ac: 0000 [#1] SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x00000000ffff0d60-0x00000000ffff0d67]
CPU: 0 UID: 0 PID: 17795 Comm: syz.0.4054 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:ip_mc_hash_remove net/ipv4/igmp.c:1431 [inline]
RIP: 0010:__ip_mc_dec_group+0x25a/0x5b0 net/ipv4/igmp.c:1774
Code: 5c db 0d f8 69 43 08 47 86 c8 61 49 bd 00 00 00 00 00 fc ff df c1 e8 17 4d 8d 24 c4 eb 2d e8 cd 75 a8 f7 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 0f 85 1e 03 00 00 4d 8b 34 24 4c 39 f3 0f 84 ef 00
RSP: 0018:ffffc900030d6da0 EFLAGS: 00010216
RAX: 000000001fffe1ac RBX: ffff88807e015200 RCX: ffffc900215b9000
RDX: 0000000000080000 RSI: ffffffff8a131583 RDI: 0000000000000001
RBP: ffff8880505b4020 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000ffff0d60
R13: dffffc0000000000 R14: 0000000000000001 R15: 00000000010000e0
FS:  00007f9a169696c0(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e310ff8 CR3: 00000000674a0000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 inetdev_event+0x3b2/0x18a0 net/ipv4/devinet.c:1642
 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2229
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 __dev_notify_flags+0x1f7/0x2e0 net/core/dev.c:9590
 netif_change_flags+0x108/0x160 net/core/dev.c:9617
 do_setlink.constprop.0+0xb53/0x4380 net/core/rtnetlink.c:3143
 rtnl_group_changelink net/core/rtnetlink.c:3775 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3929 [inline]
 rtnl_newlink+0x18e0/0x2000 net/core/rtnetlink.c:4057
 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6946
 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a15b8ebe9
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:00007f9a16969038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9a15db6180 RCX: 00007f9a15b8ebe9
RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000003
RBP: 00007f9a15c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9a15db6218 R14: 00007f9a15db6180 R15: 00007ffce16cb3d8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ip_mc_hash_remove net/ipv4/igmp.c:1431 [inline]
RIP: 0010:__ip_mc_dec_group+0x25a/0x5b0 net/ipv4/igmp.c:1774
Code: 5c db 0d f8 69 43 08 47 86 c8 61 49 bd 00 00 00 00 00 fc ff df c1 e8 17 4d 8d 24 c4 eb 2d e8 cd 75 a8 f7 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 0f 85 1e 03 00 00 4d 8b 34 24 4c 39 f3 0f 84 ef 00
RSP: 0018:ffffc900030d6da0 EFLAGS: 00010216
RAX: 000000001fffe1ac RBX: ffff88807e015200 RCX: ffffc900215b9000
RDX: 0000000000080000 RSI: ffffffff8a131583 RDI: 0000000000000001
RBP: ffff8880505b4020 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000ffff0d60
R13: dffffc0000000000 R14: 0000000000000001 R15: 00000000010000e0
FS:  00007f9a169696c0(0000) GS:ffff8881247bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000001c000 CR3: 00000000674a0000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	f8                   	clc
   1:	69 43 08 47 86 c8 61 	imul   $0x61c88647,0x8(%rbx),%eax
   8:	49 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%r13
   f:	fc ff df
  12:	c1 e8 17             	shr    $0x17,%eax
  15:	4d 8d 24 c4          	lea    (%r12,%rax,8),%r12
  19:	eb 2d                	jmp    0x48
  1b:	e8 cd 75 a8 f7       	call   0xf7a875ed
  20:	4c 89 e0             	mov    %r12,%rax
  23:	48 c1 e8 03          	shr    $0x3,%rax
* 27:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2c:	0f 85 1e 03 00 00    	jne    0x350
  32:	4d 8b 34 24          	mov    (%r12),%r14
  36:	4c 39 f3             	cmp    %r14,%rbx
  39:	0f                   	.byte 0xf
  3a:	84 ef                	test   %ch,%bh