KASAN: slab-out-of-bounds Write in __internal_add_timer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f9b9ab8d ANDROID: GKI: update abi xml file
git tree: android-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=10288cd7100000
kernel config: https://syzkaller.appspot.com/x/.config?x=8ca81bdbe6485bee
dashboard link: https://syzkaller.appspot.com/bug?extid=9e9b4b1174f911484cbe
compiler: Android (6032204 based on r370808) clang version 10.0.1 (https://android.googlesource.com/toolchain/llvm-project 6e765c10313d15c02ab29977a82938f66742c3a9)

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9e9b4b...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-out-of-bounds in hlist_add_head include/linux/list.h:787 [inline]
BUG: KASAN: slab-out-of-bounds in enqueue_timer kernel/time/timer.c:540 [inline]
BUG: KASAN: slab-out-of-bounds in __internal_add_timer+0x28d/0x490 kernel/time/timer.c:553
Write of size 8 at addr ffff88819aa13188 by task syz-executor.0/21771

CPU: 1 PID: 21771 Comm: syz-executor.0 Not tainted 5.4.51-syzkaller-00151-gf9b9ab8db435 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x14a/0x1ce lib/dump_stack.c:118
print_address_description+0x93/0x620 mm/kasan/report.c:374
__kasan_report+0x16d/0x1e0 mm/kasan/report.c:506
kasan_report+0x36/0x60 mm/kasan/common.c:634
hlist_add_head include/linux/list.h:787 [inline]
enqueue_timer kernel/time/timer.c:540 [inline]
__internal_add_timer+0x28d/0x490 kernel/time/timer.c:553
internal_add_timer kernel/time/timer.c:595 [inline]
__mod_timer+0xbf4/0x1af0 kernel/time/timer.c:1053
mod_delayed_work_on+0x105/0x190 kernel/workqueue.c:1717
mod_delayed_work include/linux/workqueue.h:530 [inline]
addrconf_mod_dad_work net/ipv6/addrconf.c:327 [inline]
addrconf_dad_kick net/ipv6/addrconf.c:3961 [inline]
addrconf_dad_run+0x4d4/0x6f0 net/ipv6/addrconf.c:4262
addrconf_notify+0x1d12/0x3790 net/ipv6/addrconf.c:3598
notifier_call_chain kernel/notifier.c:95 [inline]
__raw_notifier_call_chain kernel/notifier.c:396 [inline]
raw_notifier_call_chain+0x9e/0x100 kernel/notifier.c:403
call_netdevice_notifiers_info net/core/dev.c:1663 [inline]
__dev_notify_flags+0x3b4/0x510 net/core/dev.c:7929
dev_change_flags+0xe3/0x190 net/core/dev.c:7953
dev_ifsioc+0xff/0xb60 net/core/dev_ioctl.c:237
dev_ioctl+0x460/0xb90 net/core/dev_ioctl.c:489
sock_do_ioctl+0x26a/0x370 net/socket.c:1062
sock_ioctl+0x4cf/0x760 net/socket.c:1190
do_vfs_ioctl+0x770/0x1750 fs/ioctl.c:47
ksys_ioctl fs/ioctl.c:714 [inline]
__do_sys_ioctl fs/ioctl.c:721 [inline]
__se_sys_ioctl fs/ioctl.c:719 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:719
do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cba9
Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f937c387c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004f6020 RCX: 000000000045cba9
RDX: 0000000020000000 RSI: 0000000000008914 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000006fc R14: 00000000004c9efc R15: 00007f937c3886d4

The buggy address belongs to the page:
page:ffffea00066a8400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0
flags: 0x8000000000010000(head)
raw: 8000000000010000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88819aa13080: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
ffff88819aa13100: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
>ffff88819aa13180: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
^
ffff88819aa13200: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
ffff88819aa13280: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.