[moderation] [sound?] KASAN: vmalloc-out-of-bounds Write in copy_play_buf

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e0cce98fe279 Merge tag 'tpmdd-next-6.10-rc2' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1414bc9a980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b9016f104992d69c
dashboard link: https://syzkaller.appspot.com/bug?extid=14e710f8ffc87a461683
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [linux-...@vger.kernel.org linux...@vger.kernel.org pe...@perex.cz ti...@suse.com]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/95b83b8b8ae7/disk-e0cce98f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/32dac8e3cf35/vmlinux-e0cce98f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d2d8cd0ff617/bzImage-e0cce98f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+14e710...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: vmalloc-out-of-bounds in copy_play_buf+0x4d1/0x9a0 sound/drivers/aloop.c:603
Write of size 4096 at addr ffffc90012a5cd20 by task kworker/u8:12/2849

CPU: 1 PID: 2849 Comm: kworker/u8:12 Not tainted 6.10.0-rc1-syzkaller-00021-ge0cce98fe279 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
__asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
copy_play_buf+0x4d1/0x9a0 sound/drivers/aloop.c:603
loopback_jiffies_timer_pos_update+0xd19/0x1630 sound/drivers/aloop.c:693
loopback_jiffies_timer_function+0x64/0x240 sound/drivers/aloop.c:706
call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers kernel/time/timer.c:2417 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428
run_timer_base kernel/time/timer.c:2437 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447
handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
do_softirq+0x11b/0x1e0 kernel/softirq.c:455
</IRQ>
<TASK>
__local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:851 [inline]
__dev_queue_xmit+0x16c9/0x3d30 net/core/dev.c:4420
neigh_output include/net/neighbour.h:542 [inline]
ip6_finish_output2+0xff8/0x1670 net/ipv6/ip6_output.c:137
ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:222
NF_HOOK include/linux/netfilter.h:314 [inline]
ndisc_send_skb+0xab0/0x1380 net/ipv6/ndisc.c:509
ndisc_send_ns+0xcc/0x160 net/ipv6/ndisc.c:667
addrconf_dad_work+0xb45/0x16f0 net/ipv6/addrconf.c:4281
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

Memory state around the buggy address:
ffffc90012a5cc00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90012a5cc80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90012a5cd00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
^
ffffc90012a5cd80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90012a5ce00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================


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