CVE-2022-49505: In the Linux kernel, the following vulnerability has been resolved:  NFC: NULL out the dev->rfkill to prevent UAF  Commit 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device") assumes the device_is_registered() in function nfc_dev_up() will help to check when the rfkill is unregistered. However, this check only take effect when device_del(&dev->dev) is done in nfc_unregister_device(). Hence, the rfkill object is still possible be dereferenced.  The crash trace in latest kernel (5.18-rc2):  [   68.760105] ================================================================== [   68.760330] BUG: KASAN: use-after-free in __lock_acquire+0x3ec1/0x6750 [   68.760756] Read of size 8 at addr ffff888009c93018 by task fuzz/313 [   68.760756] [   68.760756] CPU: 0 PID: 313 Comm: fuzz Not tainted 5.18.0-rc2 #4 [   68.760756] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [   68.760756] Call Trace: [   68.760756]  <TASK> [   68.760756]  dump_stack_lvl+0x57/0x7d [   68.760756]  print_report.cold+0x5e/0x5db [   68.760756]  ? __lock_acquire+0x3ec1/0x6750 [   68.760756]  kasan_report+0xbe/0x1c0 [   68.760756]  ? __lock_acquire+0x3ec1/0x6750 [   68.760756]  __lock_acquire+0x3ec1/0x6750 [   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410 [   68.760756]  ? register_lock_class+0x18d0/0x18d0 [   68.760756]  lock_acquire+0x1ac/0x4f0 [   68.760756]  ? rfkill_blocked+0xe/0x60 [   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410 [   68.760756]  ? mutex_lock_io_nested+0x12c0/0x12c0 [   68.760756]  ? nla_get_range_signed+0x540/0x540 [   68.760756]  ? _raw_spin_lock_irqsave+0x4e/0x50 [   68.760756]  _raw_spin_lock_irqsave+0x39/0x50 [   68.760756]  ? rfkill_blocked+0xe/0x60 [   68.760756]  rfkill_blocked+0xe/0x60 [   68.760756]  nfc_dev_up+0x84/0x260 [   68.760756]  nfc_genl_dev_up+0x90/0xe0 [   68.760756]  genl_family_rcv_msg_doit+0x1f4/0x2f0 [   68.760756]  ? genl_family_rcv_msg_attrs_parse.constprop.0+0x230/0x230 [   68.760756]  ? security_capable+0x51/0x90 [   68.760756]  genl_rcv_msg+0x280/0x500 [   68.760756]  ? genl_get_cmd+0x3c0/0x3c0 [   68.760756]  ? lock_acquire+0x1ac/0x4f0 [   68.760756]  ? nfc_genl_dev_down+0xe0/0xe0 [   68.760756]  ? lockdep_hardirqs_on_prepare+0x410/0x410 [   68.760756]  netlink_rcv_skb+0x11b/0x340 [   68.760756]  ? genl_get_cmd+0x3c0/0x3c0 [   68.760756]  ? netlink_ack+0x9c0/0x9c0 [   68.760756]  ? netlink_deliver_tap+0x136/0xb00 [   68.760756]  genl_rcv+0x1f/0x30 [   68.760756]  netlink_unicast+0x430/0x710 [   68.760756]  ? memset+0x20/0x40 [   68.760756]  ? netlink_attachskb+0x740/0x740 [   68.760756]  ? __build_skb_around+0x1f4/0x2a0 [   68.760756]  netlink_sendmsg+0x75d/0xc00 [   68.760756]  ? netlink_unicast+0x710/0x710 [   68.760756]  ? netlink_unicast+0x710/0x710 [   68.760756]  sock_sendmsg+0xdf/0x110 [   68.760756]  __sys_sendto+0x19e/0x270 [   68.760756]  ? __ia32_sys_getpeername+0xa0/0xa0 [   68.760756]  ? fd_install+0x178/0x4c0 [   68.760756]  ? fd_install+0x195/0x4c0 [   68.760756]  ? kernel_fpu_begin_mask+0x1c0/0x1c0 [   68.760756]  __x64_sys_sendto+0xd8/0x1b0 [   68.760756]  ? lockdep_hardirqs_on+0xbf/0x130 [   68.760756]  ? syscall_enter_from_user_mode+0x1d/0x50 [   68.760756]  do_syscall_64+0x3b/0x90 [   68.760756]  entry_SYSCALL_64_after_hwframe+0x44/0xae [   68.760756] RIP: 0033:0x7f67fb50e6b3 ... [   68.760756] RSP: 002b:00007f67fa91fe90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [   68.760756] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f67fb50e6b3 [   68.760756] RDX: 000000000000001c RSI: 0000559354603090 RDI: 0000000000000003 [   68.760756] RBP: 00007f67fa91ff00 R08: 00007f67fa91fedc R09: 000000000000000c [   68.760756] R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe824d496e [   68.760756] R13: 00007ffe824d496f R14: 00007f67fa120000 R15: 0000000000000003  [   68.760756]  </TASK> [   68.760756] [   68.760756] Allocated by task 279: [   68.760756]  kasan_save_stack+0x1e/0x40 [ ---truncated---