SQUASHFS error: Unable to read directory block [115:26]
netlink: 72 bytes leftover after parsing attributes in process `syz-executor.4'.
SQUASHFS error: Unable to read metadata cache entry [115]
==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:704 [inline]
BUG: KASAN: use-after-free in qdisc_class_hash_insert+0x200/0x210 net/sched/sch_api.c:694
Write of size 8 at addr ffff8880aaad1b50 by task syz-executor.2/9495
SQUASHFS error: Unable to read directory block [115:26]

CPU: 1 PID: 9495 Comm: syz-executor.2 Not tainted 4.14.210-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_store8_noabort+0x68/0x70 mm/kasan/report.c:435
 hlist_add_head include/linux/list.h:704 [inline]
 qdisc_class_hash_insert+0x200/0x210 net/sched/sch_api.c:694
 qfq_change_class+0x9db/0x13f0 net/sched/sch_qfq.c:500
 tc_ctl_tclass+0x408/0xa60 net/sched/sch_api.c:1848
 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316
 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433
 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e0f9
RSP: 002b:00007f04fbe52c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e0f9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00007f04fbe52ca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007ffcda8f441f R14: 00007f04fbe539c0 R15: 000000000119bf8c

Allocated by task 9470:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618
 kmalloc include/linux/slab.h:488 [inline]
 kzalloc include/linux/slab.h:661 [inline]
 qfq_change_class+0x79f/0x13f0 net/sched/sch_qfq.c:475
 tc_ctl_tclass+0x408/0xa60 net/sched/sch_api.c:1848
 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316
 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433
 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 9470:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xc9/0x250 mm/slab.c:3815
 qfq_change_class+0xfe5/0x13f0 net/sched/sch_qfq.c:529
 tc_ctl_tclass+0x408/0xa60 net/sched/sch_api.c:1848
 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316
 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433
 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

The buggy address belongs to the object at ffff8880aaad1b40
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 16 bytes inside of
 128-byte region [ffff8880aaad1b40, ffff8880aaad1bc0)
The buggy address belongs to the page:
page:ffffea0002aab440 count:1 mapcount:0 mapping:ffff8880aaad1000 index:0xffff8880aaad13c0
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffff8880aaad1000 ffff8880aaad13c0 000000010000000e
raw: ffffea00029a45a0 ffffea0002c0ad60 ffff88813fe80640 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880aaad1a00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880aaad1a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880aaad1b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                 ^
 ffff8880aaad1b80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880aaad1c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
==================================================================