EXT4-fs (loop2): mounting ext2 file system using the ext4 subsystem
EXT4-fs (loop2): ext4_check_descriptors: Block bitmap for group 0 overlaps superblock
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x2c57/0x3f20 kernel/locking/lockdep.c:3369
Read of size 8 at addr ffff888049746a60 by task syz-executor.0/17787

CPU: 0 PID: 17787 Comm: syz-executor.0 Not tainted 4.14.232-syzkaller #0
EXT4-fs (loop2): group descriptors corrupted!
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+0x1b2/0x281 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430
 __lock_acquire+0x2c57/0x3f20 kernel/locking/lockdep.c:3369
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176
 spin_lock_bh include/linux/spinlock.h:322 [inline]
 lock_sock_nested+0x39/0x100 net/core/sock.c:2788
 l2cap_sock_teardown_cb+0x93/0x650 net/bluetooth/l2cap_sock.c:1341
 l2cap_chan_del+0xaf/0x950 net/bluetooth/l2cap_core.c:599
 l2cap_conn_del+0x36e/0x690 net/bluetooth/l2cap_core.c:1729
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7441 [inline]
 l2cap_disconn_cfm+0x7c/0xb0 net/bluetooth/l2cap_core.c:7434
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1226 [inline]
 hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1393
 hci_dev_do_close+0x535/0xca0 net/bluetooth/hci_core.c:1622
 hci_unregister_dev+0x17f/0x8c0 net/bluetooth/hci_core.c:3193
 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354
 __fput+0x25f/0x7a0 fs/file_table.c:210
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa44/0x2850 kernel/exit.c:868
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 get_signal+0x38d/0x1ca0 kernel/signal.c:2423
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665d9
RSP: 002b:00007f6679ec5188 EFLAGS: 00000246 ORIG_RAX: 0000000000000129
RAX: 0000000000000000 RBX: 000000000056bf60 RCX: 00000000004665d9
RDX: 0000000000000016 RSI: 000000000000042d RDI: 000000000000042d
RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff305a23df R14: 00007f6679ec5300 R15: 0000000000022000

Allocated by task 7944:
 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
 __do_kmalloc_node mm/slab.c:3682 [inline]
 __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3696
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 pskb_expand_head+0x128/0xd30 net/core/skbuff.c:1471
 skb_unclone include/linux/skbuff.h:1477 [inline]
 tcp_trim_head+0x109/0x460 net/ipv4/tcp_output.c:1412
 tcp_tso_acked net/ipv4/tcp_input.c:3063 [inline]
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3128 [inline]
 tcp_ack+0x2d53/0x4580 net/ipv4/tcp_input.c:3687
 tcp_rcv_established+0x4fe/0x1810 net/ipv4/tcp_input.c:5572
 tcp_v4_do_rcv+0x541/0x7d0 net/ipv4/tcp_ipv4.c:1476
 tcp_v4_rcv+0x275c/0x3560 net/ipv4/tcp_ipv4.c:1750
 ip_local_deliver_finish+0x3f2/0xab0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_local_deliver+0x167/0x460 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:476 [inline]
 ip_rcv_finish+0x6e3/0x19f0 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_rcv+0x8a7/0xf10 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x15ee/0x2a30 net/core/dev.c:4474
 __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
 netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
 napi_skb_finish net/core/dev.c:4946 [inline]
 napi_gro_receive+0x2e2/0x400 net/core/dev.c:4977
 receive_buf+0xaef/0x4b90 drivers/net/virtio_net.c:852
 virtnet_receive drivers/net/virtio_net.c:1098 [inline]
 virtnet_poll+0x4b7/0x960 drivers/net/virtio_net.c:1189
 napi_poll net/core/dev.c:5596 [inline]
 net_rx_action+0x466/0xfd0 net/core/dev.c:5662
 __do_softirq+0x24d/0x9ff kernel/softirq.c:288

Freed by task 7944:
 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
 skb_free_head net/core/skbuff.c:563 [inline]
 skb_release_data+0x5f6/0x820 net/core/skbuff.c:583
 skb_release_all net/core/skbuff.c:640 [inline]
 __kfree_skb+0x46/0x60 net/core/skbuff.c:654
 sk_wmem_free_skb include/net/sock.h:1425 [inline]
 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3187 [inline]
 tcp_ack+0x187b/0x4580 net/ipv4/tcp_input.c:3687
 tcp_rcv_established+0x4fe/0x1810 net/ipv4/tcp_input.c:5572
 tcp_v4_do_rcv+0x541/0x7d0 net/ipv4/tcp_ipv4.c:1476
 tcp_v4_rcv+0x275c/0x3560 net/ipv4/tcp_ipv4.c:1750
 ip_local_deliver_finish+0x3f2/0xab0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_local_deliver+0x167/0x460 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:476 [inline]
 ip_rcv_finish+0x6e3/0x19f0 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_rcv+0x8a7/0xf10 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x15ee/0x2a30 net/core/dev.c:4474
 __netif_receive_skb+0x27/0x1a0 net/core/dev.c:4512
 netif_receive_skb_internal+0xd7/0x580 net/core/dev.c:4585
 napi_skb_finish net/core/dev.c:4946 [inline]
 napi_gro_receive+0x2e2/0x400 net/core/dev.c:4977
 receive_buf+0xaef/0x4b90 drivers/net/virtio_net.c:852
 virtnet_receive drivers/net/virtio_net.c:1098 [inline]
 virtnet_poll+0x4b7/0x960 drivers/net/virtio_net.c:1189
 napi_poll net/core/dev.c:5596 [inline]
 net_rx_action+0x466/0xfd0 net/core/dev.c:5662
 __do_softirq+0x24d/0x9ff kernel/softirq.c:288

The buggy address belongs to the object at ffff8880497469c0
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff8880497469c0, ffff8880497471c0)
The buggy address belongs to the page:
page:ffffea000125d180 count:1 mapcount:0 mapping:ffff888049746140 index:0xffff8880497469c0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffff888049746140 ffff8880497469c0 0000000100000002
raw: ffffea000148d2a0 ffffea0001552320 ffff88813fe80c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888049746900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888049746980: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff888049746a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff888049746a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888049746b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================