syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 1 UID: 0 PID: 6005 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:generic_hwtstamp_ioctl_lower+0x185/0x380 net/core/dev_ioctl.c:447
Code: 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 e1 01 00 00 48 be 00 00 00 00 00 fc ff df 49 8b 45 10 48 8d 78 10 48 89 fa 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 27 49 89 d0 83 e2 07 49 c1 e8 03 41 0f b6 34
RSP: 0018:ffffc900030b7270 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 1ffff92000616e50 RCX: 0000000000000000
RDX: 0000000000000002 RSI: dffffc0000000000 RDI: 0000000000000010
RBP: ffffc900030b7348 R08: 0000000000000001 R09: 0000000000000003
R10: ffffc900030b72bb R11: 0000000000000000 R12: ffffc900030b7438
R13: ffffc900030b7428 R14: ffff88807962e000 R15: ffffc900030b72b0
FS:  00005555812eb500(0000) GS:ffff888124f6f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000002080 CR3: 00000000752ca000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 generic_hwtstamp_get_lower net/core/dev_ioctl.c:478 [inline]
 generic_hwtstamp_get_lower+0x269/0x360 net/core/dev_ioctl.c:459
 dev_get_hwtstamp_phylib+0x181/0x610 net/core/dev_ioctl.c:278
 tsconfig_prepare_data+0x15e/0x620 net/ethtool/tsconfig.c:51
 ethnl_default_doit+0x3ce/0xed0 net/ethtool/netlink.c:529
 genl_family_rcv_msg_doit+0x209/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5a7/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0xa95/0xc70 net/socket.c:2630
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2684
 __sys_sendmsg+0x16d/0x220 net/socket.c:2716
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc6ad8eec9
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:00007ffdd0f15188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fcc6afe5fa0 RCX: 00007fcc6ad8eec9
RDX: 0000000000000000 RSI: 0000200000002080 RDI: 0000000000000003
RBP: 00007fcc6ae11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcc6afe5fa0 R14: 00007fcc6afe5fa0 R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:generic_hwtstamp_ioctl_lower+0x185/0x380 net/core/dev_ioctl.c:447
Code: 4c 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 e1 01 00 00 48 be 00 00 00 00 00 fc ff df 49 8b 45 10 48 8d 78 10 48 89 fa 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 27 49 89 d0 83 e2 07 49 c1 e8 03 41 0f b6 34
RSP: 0018:ffffc900030b7270 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 1ffff92000616e50 RCX: 0000000000000000
RDX: 0000000000000002 RSI: dffffc0000000000 RDI: 0000000000000010
RBP: ffffc900030b7348 R08: 0000000000000001 R09: 0000000000000003
R10: ffffc900030b72bb R11: 0000000000000000 R12: ffffc900030b7438
R13: ffffc900030b7428 R14: ffff88807962e000 R15: ffffc900030b72b0
FS:  00005555812eb500(0000) GS:ffff888124e6f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe57368f08 CR3: 00000000752ca000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	4c 89 e2             	mov    %r12,%rdx
   3:	48 c1 ea 03          	shr    $0x3,%rdx
   7:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   b:	0f 85 e1 01 00 00    	jne    0x1f2
  11:	48 be 00 00 00 00 00 	movabs $0xdffffc0000000000,%rsi
  18:	fc ff df
  1b:	49 8b 45 10          	mov    0x10(%r13),%rax
  1f:	48 8d 78 10          	lea    0x10(%rax),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	0f b6 0c 32          	movzbl (%rdx,%rsi,1),%ecx <-- trapping instruction
  2e:	48 8d 50 27          	lea    0x27(%rax),%rdx
  32:	49 89 d0             	mov    %rdx,%r8
  35:	83 e2 07             	and    $0x7,%edx
  38:	49 c1 e8 03          	shr    $0x3,%r8
  3c:	41                   	rex.B
  3d:	0f                   	.byte 0xf
  3e:	b6 34                	mov    $0x34,%dh