syzbot

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add_uevent_var: buffer size too small
WARNING: CPU: 1 PID: 4470 at lib/kobject_uevent.c:594 add_uevent_var+0x2aa/0x2d0 lib/kobject_uevent.c:594
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 4470 Comm: syzkaller765082 Not tainted 4.16.0+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x1f4/0x2b0 lib/bug.c:186
 fixup_bug.part.10+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:986
RIP: 0010:add_uevent_var+0x2aa/0x2d0 lib/kobject_uevent.c:594
RSP: 0018:ffff8801ad91e810 EFLAGS: 00010286
RAX: dffffc0000000008 RBX: ffff8801d95d6340 RCX: ffffffff815b193e
RDX: 0000000000000000 RSI: 1ffff10035b23cb2 RDI: 1ffff10035b23c87
RBP: ffff8801ad91e8d8 R08: 1ffff10035b23c49 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000000 R12: 1ffff10035b23d03
R13: ffff8801d95d6458 R14: 00000000000003e6 R15: 0000000000000438
 rfkill_dev_uevent+0x31/0x170 net/rfkill/core.c:813
 dev_uevent+0x2b6/0x7e0 drivers/base/core.c:913
 kobject_uevent_env+0x3fe/0xd30 lib/kobject_uevent.c:476
 kobject_uevent+0x1f/0x30 lib/kobject_uevent.c:565
 device_add+0xd04/0x1650 drivers/base/core.c:1834
 rfkill_register+0x254/0xd60 net/rfkill/core.c:1019
 wiphy_register+0x19d1/0x2050 net/wireless/core.c:872
 ieee80211_register_hw+0x1162/0x3100 net/mac80211/main.c:1041
 mac80211_hwsim_new_radio+0x1d06/0x2fb0 drivers/net/wireless/mac80211_hwsim.c:2757
 hwsim_new_radio_nl+0x67a/0x8c0 drivers/net/wireless/mac80211_hwsim.c:3214
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:599
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624
 netlink_rcv_skb+0x14b/0x380 net/netlink/af_netlink.c:2447
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:635
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x4c4/0x6b0 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2046
 __sys_sendmsg+0xe5/0x210 net/socket.c:2080
 SYSC_sendmsg net/socket.c:2091 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2087
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x43fda9
RSP: 002b:00007fffa3f95a48 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9
RDX: 0000000000000000 RSI: 0000000020b3dfc8 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 00000000004016d0
R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..