Process accounting resumed
print_req_error: I/O error, dev loop5, sector 6
Process accounting resumed
Buffer I/O error on dev loop5, logical block 3, async page read
==================================================================
BUG: KASAN: use-after-free in add_chain fs/minix/itree_common.c:14 [inline]
BUG: KASAN: use-after-free in get_branch fs/minix/itree_common.c:52 [inline]
BUG: KASAN: use-after-free in get_block+0xe06/0x1100 fs/minix/itree_common.c:160
Read of size 2 at addr ffff8880a05450b6 by task syz-executor.0/13621

CPU: 0 PID: 13621 Comm: syz-executor.0 Not tainted 4.14.183-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+0x54/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393
 add_chain fs/minix/itree_common.c:14 [inline]
 get_branch fs/minix/itree_common.c:52 [inline]
 get_block+0xe06/0x1100 fs/minix/itree_common.c:160
 minix_get_block+0xd6/0x100 fs/minix/inode.c:379
 __block_write_begin_int+0x33a/0x1000 fs/buffer.c:2038
 __block_write_begin fs/buffer.c:2088 [inline]
 block_write_begin+0x58/0x260 fs/buffer.c:2147
 minix_write_begin+0x35/0xc0 fs/minix/inode.c:415
 generic_perform_write+0x1c9/0x420 mm/filemap.c:3047
 __generic_file_write_iter+0x227/0x590 mm/filemap.c:3172
 generic_file_write_iter+0x36f/0x650 mm/filemap.c:3200
 call_write_iter include/linux/fs.h:1778 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x44e/0x630 fs/read_write.c:482
 __kernel_write+0xf5/0x330 fs/read_write.c:501
 do_acct_process+0xb49/0xf60 kernel/acct.c:520
 acct_pin_kill+0x28/0xe0 kernel/acct.c:174
 pin_kill+0x147/0x650 fs/fs_pin.c:50
 mnt_pin_kill+0x62/0x170 fs/fs_pin.c:87
 cleanup_mnt+0x110/0x140 fs/namespace.c:1180
 task_work_run+0x113/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
 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: 0033:0x45ca69
RSP: 002b:00007f934503dc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000000000050a100 RCX: 000000000045ca69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000500
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000c4a R14: 00000000004ce9e6 R15: 00007f934503e6d4

Allocated by task 12893:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.0+0x4f/0xd0 mm/kasan/kasan.c:551
 kmem_cache_alloc+0x124/0x3c0 mm/slab.c:3552
 shmem_alloc_inode+0x18/0x40 mm/shmem.c:3888
 alloc_inode+0x5d/0x170 fs/inode.c:210
 new_inode_pseudo+0x14/0xe0 fs/inode.c:899
 new_inode+0x1b/0x40 fs/inode.c:928
 shmem_get_inode+0x74/0x780 mm/shmem.c:2176
 shmem_symlink+0xb0/0x6c0 mm/shmem.c:3261
 vfs_symlink+0x320/0x530 fs/namei.c:4156
 SYSC_symlinkat fs/namei.c:4183 [inline]
 SyS_symlinkat+0x193/0x1f0 fs/namei.c:4163
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 17:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758
 __rcu_reclaim kernel/rcu/rcu.h:195 [inline]
 rcu_do_batch kernel/rcu/tree.c:2699 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline]
 rcu_process_callbacks+0x78d/0x1180 kernel/rcu/tree.c:2946
 __do_softirq+0x254/0x9bf kernel/softirq.c:288

The buggy address belongs to the object at ffff8880a0545000
 which belongs to the cache shmem_inode_cache of size 1208
The buggy address is located 182 bytes inside of
 1208-byte region [ffff8880a0545000, ffff8880a05454b8)
The buggy address belongs to the page:
page:ffffea0002815140 count:1 mapcount:0 mapping:ffff8880a0545000 index:0xffff8880a0545ffd
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff8880a0545000 ffff8880a0545ffd 0000000100000003
raw: ffffea00026e3a60 ffffea000296b260 ffff8880aa9da3c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a0544f80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880a0545000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880a0545080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8880a0545100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a0545180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================