[syzbot] [wireless?] UBSAN: array-index-out-of-bounds in ieee80211_request_ibss_scan (2)

[syzbot <syzbot+e834e757bd9b3d3e1251@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    47c84997c686 selftests: net: lib: fix shift count out of r..
git tree:       net
console output: https://syzkaller.appspot.com/x/log.txt?x=16ef60f0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b309c907eaab29da
dashboard link: https://syzkaller.appspot.com/bug?extid=e834e757bd9b3d3e1251
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/10b34cf37026/disk-47c84997.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/953c1fdde5ac/vmlinux-47c84997.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6f870a400c55/bzImage-47c84997.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e834e757bd9b3d3e1251@syzkaller.appspotmail.com

wlan0: No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:1223:5
index 11 is out of range for type 'struct ieee80211_channel *[] __counted_by(n_channels)' (aka 'struct ieee80211_channel *[]')
CPU: 1 UID: 0 PID: 49 Comm: kworker/u8:3 Not tainted 6.16.0-rc5-syzkaller-00159-g47c84997c686 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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_request_ibss_scan+0x600/0x8b0 net/mac80211/scan.c:1223
 ieee80211_sta_merge_ibss net/mac80211/ibss.c:1283 [inline]
 ieee80211_ibss_work+0xd85/0x1060 net/mac80211/ibss.c:1665
 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+0x3fc/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: 1 UID: 0 PID: 49 Comm: kworker/u8:3 Not tainted 6.16.0-rc5-syzkaller-00159-g47c84997c686 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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_request_ibss_scan+0x600/0x8b0 net/mac80211/scan.c:1223
 ieee80211_sta_merge_ibss net/mac80211/ibss.c:1283 [inline]
 ieee80211_ibss_work+0xd85/0x1060 net/mac80211/ibss.c:1665
 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+0x3fc/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..


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