Re: [syzbot] [wireless?] UBSAN: array-index-out-of-bounds in ieee80211_rx_mgmt_beacon

[syzbot <syzbot+6554b492c7008bcd3385@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
UBSAN: array-index-out-of-bounds in ieee80211_rx_mgmt_beacon

------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in net/mac80211/mlme.c:7224:41
index 4 is out of range for type 'u8[0]' (aka 'unsigned char[0]')
CPU: 0 UID: 0 PID: 1041 Comm: kworker/u4:8 Not tainted 6.16.0-rc2-syzkaller-g9afe652958c3-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
 ieee80211_rx_mgmt_beacon+0x24be/0x2f20 net/mac80211/mlme.c:7224
 ieee80211_iface_process_skb net/mac80211/iface.c:1630 [inline]
 ieee80211_iface_work+0x49c/0xfe0 net/mac80211/iface.c:1722
 cfg80211_wiphy_work+0x2df/0x460 net/wireless/core.c:435
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
---[ end trace ]---
Kernel panic - not syncing: UBSAN: panic_on_warn set ...
CPU: 0 UID: 0 PID: 1041 Comm: kworker/u4:8 Not tainted 6.16.0-rc2-syzkaller-g9afe652958c3-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound cfg80211_wiphy_work
Call Trace:
 <TASK>
 dump_stack_lvl+0x99/0x250 lib/dump_stack.c:120
 panic+0x2db/0x790 kernel/panic.c:382
 check_panic_on_warn+0x89/0xb0 kernel/panic.c:273
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
 ieee80211_rx_mgmt_beacon+0x24be/0x2f20 net/mac80211/mlme.c:7224
 ieee80211_iface_process_skb net/mac80211/iface.c:1630 [inline]
 ieee80211_iface_work+0x49c/0xfe0 net/mac80211/iface.c:1722
 cfg80211_wiphy_work+0x2df/0x460 net/wireless/core.c:435
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..


Tested on:

commit:         9afe6529 Merge tag 'x86_urgent_for_6.16-rc3' of git://..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12db1e82580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d11f52d3049c3790
dashboard link: https://syzkaller.appspot.com/bug?extid=6554b492c7008bcd3385
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12ae190c580000