[Android 6.1] KASAN: use-after-free Read in rcu_cblist_dequeue

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: bf32db543281 ANDROID: GKI: update xiaomi symbol list
git tree: android14-6.1
console output: https://syzkaller.appspot.com/x/log.txt?x=10ff33d2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=69841d35933a4e41
dashboard link: https://syzkaller.appspot.com/bug?extid=9da04cc1c19a8165b176
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=128a03b6580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=125218ae580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b0af0e459d63/disk-bf32db54.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/99d96ebb58b6/vmlinux-bf32db54.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cb45eb366201/bzImage-bf32db54.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9da04c...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
Read of size 8 at addr ffff88810cfccd90 by task ksoftirqd/0/13

CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
<TASK>
__dump_stack+0x21/0x24 lib/dump_stack.c:88
dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
print_address_description+0x71/0x200 mm/kasan/report.c:316
print_report+0x4a/0x60 mm/kasan/report.c:420
kasan_report+0x122/0x150 mm/kasan/report.c:524
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
rcu_do_batch+0x4bb/0xbc0 kernel/rcu/tree.c:2285
rcu_core+0x5c3/0xe80 kernel/rcu/tree.c:2557
rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
handle_softirqs+0x1d7/0x600 kernel/softirq.c:642


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