Re: [syzbot] general protection fault in hwsim_new_edge_nl

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    2a2b6e3640c4 devlink: Fix port_type_set function pointer c..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11abd8a1300000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8075b2614f3db143
dashboard link: https://syzkaller.appspot.com/bug?extid=fafb46da3f65fdbacd16
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13371f79300000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16fabc4a300000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fafb46da3f65fdbacd16@xxxxxxxxxxxxxxxxxxxxxxxxx

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 8442 Comm: syz-executor760 Not tainted 5.14.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:nla_len include/net/netlink.h:1148 [inline]
RIP: 0010:nla_parse_nested_deprecated include/net/netlink.h:1231 [inline]
RIP: 0010:hwsim_new_edge_nl+0xf4/0x8c0 drivers/net/ieee802154/mac802154_hwsim.c:425
Code: 00 0f 85 76 07 00 00 4d 85 ed 48 8b 5b 10 0f 84 5e 05 00 00 e8 0d e3 40 fc 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 87
RSP: 0018:ffffc9000178f568 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8534cab3 RDI: ffff88801dd72a10
RBP: ffffc9000178f678 R08: 0000000000000001 R09: ffffc9000178f6a8
R10: fffff520002f1ed6 R11: 0000000000000000 R12: ffffc9000178f698
R13: ffff888025fbd014 R14: ffff8880278afb40 R15: 0000000000000000
FS:  00000000013a1300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000744 CR3: 0000000031221000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2403
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2457
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43ef39
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff22c3c298 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ef39
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 0000000000402f20 R08: 0000000000000000 R09: 0000000000400488
R10: 00000000004ac018 R11: 0000000000000246 R12: 0000000000402fb0
R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488
Modules linked in:
---[ end trace 63fa4e15cfb16ac5 ]---
RIP: 0010:nla_len include/net/netlink.h:1148 [inline]
RIP: 0010:nla_parse_nested_deprecated include/net/netlink.h:1231 [inline]
RIP: 0010:hwsim_new_edge_nl+0xf4/0x8c0 drivers/net/ieee802154/mac802154_hwsim.c:425
Code: 00 0f 85 76 07 00 00 4d 85 ed 48 8b 5b 10 0f 84 5e 05 00 00 e8 0d e3 40 fc 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 87
RSP: 0018:ffffc9000178f568 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8534cab3 RDI: ffff88801dd72a10
RBP: ffffc9000178f678 R08: 0000000000000001 R09: ffffc9000178f6a8
R10: fffff520002f1ed6 R11: 0000000000000000 R12: ffffc9000178f698
R13: ffff888025fbd014 R14: ffff8880278afb40 R15: 0000000000000000
FS:  00000000013a1300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000744 CR3: 0000000031221000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400