netlink: 28 bytes leftover after parsing attributes in process `syz.0.17'. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 5961 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:nla_len include/net/netlink.h:1296 [inline] RIP: 0010:parse_attr net/sched/sch_netem.c:960 [inline] RIP: 0010:netem_quirk_chk+0x8a/0x740 net/sched/sch_netem.c:990 Code: 7c 24 60 49 c1 ef 03 43 c7 04 27 f1 f1 f1 f1 43 c7 44 27 13 f3 f3 f3 f3 43 c6 44 27 17 f3 e8 8d 68 67 f8 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 32 06 00 00 0f b7 03 83 c0 fc 44 0f b7 RSP: 0018:ffffc900032c7140 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88810ff73a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881b82ce000 RBP: ffffc900032c72b8 R08: ffff88810ff73a00 R09: 0000000000000002 R10: 00000000fffffff1 R11: ffffffff89589ab0 R12: dffffc0000000000 R13: ffffffff89589ab0 R14: ffffffff8f7d9580 R15: 1ffff92000658e34 FS: 000055558efa7500(0000) GS:ffff8882a9f35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000100 CR3: 0000000114760000 CR4: 00000000000006f0 Call Trace: qdisc_create+0x73f/0xf10 net/sched/sch_api.c:1319 __tc_modify_qdisc net/sched/sch_api.c:1765 [inline] tc_modify_qdisc+0x1582/0x2140 net/sched/sch_api.c:1829 rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6967 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x830 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1beb98f749 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:00007ffd1afcc778 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f1bebbe5fa0 RCX: 00007f1beb98f749 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000003 RBP: 00007f1beba13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1bebbe5fa0 R14: 00007f1bebbe5fa0 R15: 0000000000000003 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:nla_len include/net/netlink.h:1296 [inline] RIP: 0010:parse_attr net/sched/sch_netem.c:960 [inline] RIP: 0010:netem_quirk_chk+0x8a/0x740 net/sched/sch_netem.c:990 Code: 7c 24 60 49 c1 ef 03 43 c7 04 27 f1 f1 f1 f1 43 c7 44 27 13 f3 f3 f3 f3 43 c6 44 27 17 f3 e8 8d 68 67 f8 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 32 06 00 00 0f b7 03 83 c0 fc 44 0f b7 RSP: 0018:ffffc900032c7140 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88810ff73a00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881b82ce000 RBP: ffffc900032c72b8 R08: ffff88810ff73a00 R09: 0000000000000002 R10: 00000000fffffff1 R11: ffffffff89589ab0 R12: dffffc0000000000 R13: ffffffff89589ab0 R14: ffffffff8f7d9580 R15: 1ffff92000658e34 FS: 000055558efa7500(0000) GS:ffff8882a9f35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000100 CR3: 0000000114760000 CR4: 00000000000006f0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 24 60 and $0x60,%al 2: 49 c1 ef 03 shr $0x3,%r15 6: 43 c7 04 27 f1 f1 f1 movl $0xf1f1f1f1,(%r15,%r12,1) d: f1 e: 43 c7 44 27 13 f3 f3 movl $0xf3f3f3f3,0x13(%r15,%r12,1) 15: f3 f3 17: 43 c6 44 27 17 f3 movb $0xf3,0x17(%r15,%r12,1) 1d: e8 8d 68 67 f8 call 0xf86768af 22: 48 89 d8 mov %rbx,%rax 25: 48 c1 e8 03 shr $0x3,%rax * 29: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 32 06 00 00 jne 0x668 36: 0f b7 03 movzwl (%rbx),%eax 39: 83 c0 fc add $0xfffffffc,%eax 3c: 44 rex.R 3d: 0f .byte 0xf 3e: b7 .byte 0xb7