Hello,

I observe the same callstack on Ubuntu 20.04.06 LTS after trying to enable monitor mode:
sudo ip link set dev wlp82s0 down
sudo iwconfig wlp82s0 mode monitor
// Callstack visible after that command
sudo ip link set dev wlp82s0 up

When I call those commands again then callstack is not seen, but monitor mode not works and I am unable to do wifi sniffing. Wifi sniffing stopped working today. Reboot of PC does not help.

PC: Lenovo P53
Info about wifi driver:
$ cat dmesg.txt | grep -E "wifi|wlp82s0"
[   29.785225] iwlwifi 0000:52:00.0: enabling device (0000 -> 0002)
[   29.807499] iwlwifi 0000:52:00.0: api flags index 2 larger than supported by driver
[   29.807514] iwlwifi 0000:52:00.0: TLV_FW_FSEQ_VERSION: FSEQ Version: 89.3.35.37
[   29.807735] iwlwifi 0000:52:00.0: loaded firmware version 66.f1c864e0.0 cc-a0-66.ucode op_mode iwlmvm
[   29.971841] iwlwifi 0000:52:00.0: BIOS contains WGDS but no WRDS
[   29.971851] iwlwifi 0000:52:00.0: Detected Intel(R) Wi-Fi 6 AX200 160MHz, REV=0x340
[   30.131778] iwlwifi 0000:52:00.0: Detected RF HR B3, rfid=0x10a100
[   30.201478] iwlwifi 0000:52:00.0: base HW address: f8:e4:e3:d9:d2:ee
[   30.578367] iwlwifi 0000:52:00.0 wlp82s0: renamed from wlan0

callstack:
[  502.483818] ================================================================================
[  502.483829] UBSAN: shift-out-of-bounds in /build/linux-hwe-5.15-x48ylI/linux-hwe-5.15-5.15.0/drivers/net/wireless/intel/iwlwifi/mvm/mac-ctxt.c:669:22
[  502.483841] shift exponent 65535 is too large for 64-bit type 'long unsigned int'
[  502.483851] CPU: 0 PID: 5401 Comm: ip Tainted: P           OE     5.15.0-69-generic #76~20.04.1-Ubuntu
[  502.483862] Hardware name: LENOVO 20QNS1T600/20QNS1T600, BIOS N2NET38W (1.23 ) 06/04/2020
[  502.483866] Call Trace:
[  502.483871]  <TASK>
[  502.483877]  dump_stack_lvl+0x4a/0x63
[  502.483890]  dump_stack+0x10/0x16
[  502.483896]  ubsan_epilogue+0x9/0x49
[  502.483909]  __ubsan_handle_shift_out_of_bounds.cold+0x61/0x10e
[  502.483929]  iwl_mvm_mac_ctxt_cmd_listener.cold+0x20/0x32 [iwlmvm]
[  502.484008]  iwl_mvm_mac_ctx_send+0x8b/0xd0 [iwlmvm]
[  502.484061]  iwl_mvm_mac_ctxt_add+0x44/0xf0 [iwlmvm]
[  502.484108]  iwl_mvm_mac_add_interface+0x133/0x350 [iwlmvm]
[  502.484153]  drv_add_interface+0x47/0x100 [mac80211]
[  502.484266]  ieee80211_add_virtual_monitor+0x11a/0x330 [mac80211]
[  502.484392]  ieee80211_do_open+0x867/0x970 [mac80211]
[  502.484511]  ? ieee80211_check_concurrent_iface+0x158/0x1d0 [mac80211]
[  502.484629]  ieee80211_open+0x70/0x90 [mac80211]
[  502.484744]  __dev_open+0xe5/0x1a0
[  502.484757]  __dev_change_flags+0x190/0x200
[  502.484770]  dev_change_flags+0x26/0x70
[  502.484781]  do_setlink+0x907/0xc40
[  502.484796]  ? __nla_validate_parse+0x4c/0x1a0
[  502.484811]  __rtnl_newlink+0x593/0xa10
[  502.484822]  ? __nla_reserve+0x41/0x60
[  502.484832]  ? __kmalloc_node_track_caller+0x1d0/0x4e0
[  502.484843]  ? skb_free_head+0x69/0x80
[  502.484854]  ? security_sock_rcv_skb+0x2c/0x50
[  502.484868]  ? netlink_deliver_tap+0x3d/0x230
[  502.484876]  ? sk_filter_trim_cap+0xc1/0x230
[  502.484889]  ? skb_queue_tail+0x48/0x60
[  502.484898]  ? sock_def_readable+0x4b/0x80
[  502.484905]  ? __netlink_sendskb+0x3f/0x60
[  502.484913]  ? netlink_unicast+0x21b/0x250
[  502.484924]  ? rtnl_getlink+0x37c/0x400
[  502.484950]  ? __cond_resched+0x19/0x40
[  502.484963]  ? kmem_cache_alloc_trace+0x15a/0x420
[  502.484972]  rtnl_newlink+0x49/0x70
[  502.484982]  rtnetlink_rcv_msg+0x15d/0x410
[  502.484994]  ? __cond_resched+0x19/0x40
[  502.485004]  ? rtnl_calcit.isra.0+0x130/0x130
[  502.485015]  netlink_rcv_skb+0x53/0x100
[  502.485026]  rtnetlink_rcv+0x15/0x20
[  502.485034]  netlink_unicast+0x1ab/0x250
[  502.485043]  netlink_sendmsg+0x23e/0x4a0
[  502.485055]  sock_sendmsg+0x66/0x70
[  502.485067]  ____sys_sendmsg+0x21c/0x290
[  502.485076]  ? copy_msghdr_from_user+0x5c/0x90
[  502.485091]  ___sys_sendmsg+0x81/0xc0
[  502.485103]  ? mntput_no_expire+0x4c/0x260
[  502.485112]  ? __cond_resched+0x19/0x40
[  502.485123]  ? security_file_free+0x54/0x60
[  502.485132]  ? call_rcu+0xa8/0x230
[  502.485144]  ? __fput+0x127/0x280
[  502.485158]  __sys_sendmsg+0x62/0xc0
[  502.485171]  ? handle_mm_fault+0xd9/0x2c0
[  502.485181]  __x64_sys_sendmsg+0x1f/0x30
[  502.485191]  do_syscall_64+0x59/0xc0
[  502.485203]  ? irqentry_exit_to_user_mode+0x9/0x20
[  502.485211]  ? irqentry_exit+0x1d/0x30
[  502.485218]  ? exc_page_fault+0x89/0x170
[  502.485225]  entry_SYSCALL_64_after_hwframe+0x61/0xcb
[  502.485235] RIP: 0033:0x7f342cf485e7
[  502.485245] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
[  502.485252] RSP: 002b:00007ffe89aee5a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  502.485263] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f342cf485e7
[  502.485269] RDX: 0000000000000000 RSI: 00007ffe89aee620 RDI: 0000000000000003
[  502.485273] RBP: 000000006437ce8c R08: 0000000000000001 R09: 000000000000007c
[  502.485278] R10: 00007f342d014be0 R11: 0000000000000246 R12: 0000000000000001
[  502.485283] R13: 00007ffe89aeee00 R14: 00007ffe89aee6f0 R15: 000055702574a020
[  502.485295]  </TASK>
[  502.485299] ================================================================================