CVE-2023-53028 – Linux Kernel WiFi mac80211 Null Pointer Dereference Vulnerability

Revert “wifi: mac80211: fix memory leak in ieee80211_if_add()”

This reverts commit 13e5afd3d773c6fc6ca2b89027befaaaa1ea7293.

ieee80211_if_free() is already called from free_netdev(ndev)
because ndev->priv_destructor == ieee80211_if_free

syzbot reported:

general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 0 PID: 10041 Comm: syz-executor.0 Not tainted 6.2.0-rc2-syzkaller-00388-g55b98837e37d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:pcpu_get_page_chunk mm/percpu.c:262 [inline]
RIP: 0010:pcpu_chunk_addr_search mm/percpu.c:1619 [inline]
RIP: 0010:free_percpu mm/percpu.c:2271 [inline]
RIP: 0010:free_percpu+0x186/0x10f0 mm/percpu.c:2254
Code: 80 3c 02 00 0f 85 f5 0e 00 00 48 8b 3b 48 01 ef e8 cf b3 0b 00 48 ba 00 00 00 00 00 fc ff df 48 8d 78 20 48 89 f9 48 c1 e9 03 3c 11 00 0f 85 3b 0e 00 00 48 8b 58 20 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90004ba7068 EFLAGS: 00010002
RAX: 0000000000000000 RBX: ffff88823ffe2b80 RCX: 0000000000000004
RDX: dffffc0000000000 RSI: ffffffff81c1f4e7 RDI: 0000000000000020
RBP: ffffe8fffe8fc220 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 1ffffffff2179ab2 R12: ffff8880b983d000
R13: 0000000000000003 R14: 0000607f450fc220 R15: ffff88823ffe2988
FS: 00007fcb349de700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32220000 CR3: 000000004914f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

netdev_run_todo+0x6bf/0x1100 net/core/dev.c:10352
ieee80211_register_hw+0x2663/0x4040 net/mac80211/main.c:1411
mac80211_hwsim_new_radio+0x2537/0x4d80 drivers/net/wireless/mac80211_hwsim.c:4583
hwsim_new_radio_nl+0xa09/0x10f0 drivers/net/wireless/mac80211_hwsim.c:5176
genl_family_rcv_msg_doit.isra.0+0x1e6/0x2d0 net/netlink/genetlink.c:968
genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline]
genl_rcv_msg+0x4ff/0x7e0 net/netlink/genetlink.c:1065
netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356
netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xd3/0x120 net/socket.c:734
____sys_sendmsg+0x712/0x8c0 net/socket.c:2476
___sys_sendmsg+0x110/0x1b0 net/socket.c:2530
__sys_sendmsg+0xf7/0x1c0 net/socket.c:2559
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd