BUG: kernel NULL pointer dereference, address: 00000000000004d0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 800000011671b067 P4D 800000011671b067 PUD 11d7c3067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 UID: 0 PID: 3336 Comm: syz.0.15 Not tainted 6.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:phy_start_cable_test_tdr+0x11/0x1e0 drivers/net/phy/phy.c:888 Code: 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 89 f5 <48> 8b 87 d0 04 00 00 48 85 c0 74 65 48 83 b8 88 01 00 00 00 74 5b RSP: 0018:ffffc90005a178e8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff828d86b8 RCX: 8c88689433416b00 RDX: ffffc90005a17928 RSI: ffffc90005a17ac0 RDI: 0000000000000000 RBP: ffffc90005a17ac0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff81c0aa50 R12: 0000000000000000 R13: ffffc90005a17a38 R14: 00000000ffffffa1 R15: ffff88811d648000 FS: 00007f409d3386c0(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000004d0 CR3: 0000000113860000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ethnl_act_cable_test_tdr+0x32d/0x400 net/ethtool/cabletest.c:350 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x391/0x3d0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0xe0/0x110 net/netlink/af_netlink.c:2550 genl_rcv+0x23/0x30 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x236/0x320 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x32d/0x3c0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x8e/0xb0 net/socket.c:745 ____sys_sendmsg+0x1a7/0x200 net/socket.c:2597 ___sys_sendmsg+0x28f/0x2d0 net/socket.c:2651 __sys_sendmsg net/socket.c:2680 [inline] __do_sys_sendmsg net/socket.c:2689 [inline] __se_sys_sendmsg+0xf7/0x140 net/socket.c:2687 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x8d/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f409d8b9e79 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:00007f409d338038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f409da55f80 RCX: 00007f409d8b9e79 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003 RBP: 00007f409d92793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f409da55f80 R15: 00007ffd9c4ec8b8 Modules linked in: CR2: 00000000000004d0 ---[ end trace 0000000000000000 ]--- RIP: 0010:phy_start_cable_test_tdr+0x11/0x1e0 drivers/net/phy/phy.c:888 Code: 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 89 f5 <48> 8b 87 d0 04 00 00 48 85 c0 74 65 48 83 b8 88 01 00 00 00 74 5b RSP: 0018:ffffc90005a178e8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff828d86b8 RCX: 8c88689433416b00 RDX: ffffc90005a17928 RSI: ffffc90005a17ac0 RDI: 0000000000000000 RBP: ffffc90005a17ac0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff81c0aa50 R12: 0000000000000000 R13: ffffc90005a17a38 R14: 00000000ffffffa1 R15: ffff88811d648000 FS: 00007f409d3386c0(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000004d0 CR3: 0000000113860000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 7: 00 00 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: f3 0f 1e fa endbr64 1d: 55 push %rbp 1e: 41 57 push %r15 20: 41 56 push %r14 22: 41 55 push %r13 24: 41 54 push %r12 26: 53 push %rbx 27: 48 89 f5 mov %rsi,%rbp * 2a: 48 8b 87 d0 04 00 00 mov 0x4d0(%rdi),%rax <-- trapping instruction 31: 48 85 c0 test %rax,%rax 34: 74 65 je 0x9b 36: 48 83 b8 88 01 00 00 cmpq $0x0,0x188(%rax) 3d: 00 3e: 74 5b je 0x9b