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BUG: KASAN: use-after-free in lbmIODone+0xb75/0xe00 fs/jfs/jfs_logmgr.c:2206
Read of size 4 at addr ffff8880aab8b908 by task loop0/19967

CPU: 0 PID: 19967 Comm: loop0 Not tainted 4.14.206-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_load4_noabort+0x68/0x70 mm/kasan/report.c:429
 lbmIODone+0xb75/0xe00 fs/jfs/jfs_logmgr.c:2206
 bio_endio+0x27a/0x680 block/bio.c:1918
 req_bio_endio block/blk-core.c:204 [inline]
 blk_update_request+0x2d0/0xa30 block/blk-core.c:2765
 blk_mq_end_request+0x4c/0x1e0 block/blk-mq.c:530
 __blk_mq_complete_request+0x30b/0x6c0 block/blk-mq.c:571
 blk_mq_complete_request+0x52/0x60 block/blk-mq.c:591
 loop_handle_cmd drivers/block/loop.c:1784 [inline]
 loop_queue_work+0x227/0x1e80 drivers/block/loop.c:1793
 kthread_worker_fn+0x271/0x6c0 kernel/kthread.c:642
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Allocated by task 19965:
 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]
 lbmLogInit fs/jfs/jfs_logmgr.c:1842 [inline]
 lmLogInit+0x2f1/0x12f0 fs/jfs/jfs_logmgr.c:1292
 open_inline_log fs/jfs/jfs_logmgr.c:1197 [inline]
 lmLogOpen+0x6b1/0x10e0 fs/jfs/jfs_logmgr.c:1090
 jfs_mount_rw+0x236/0x430 fs/jfs/jfs_mount.c:271
 jfs_fill_super+0x78a/0xab0 fs/jfs/super.c:598
 mount_bdev+0x2b3/0x360 fs/super.c:1134
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0xe53/0x2a00 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3072
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 8012:
 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
 lbmLogShutdown fs/jfs/jfs_logmgr.c:1885 [inline]
 lmLogShutdown+0x2a9/0x540 fs/jfs/jfs_logmgr.c:1705
 lmLogClose+0x464/0x5d0 fs/jfs/jfs_logmgr.c:1481
 jfs_umount+0x25f/0x310 fs/jfs/jfs_umount.c:129
 jfs_put_super+0x61/0x140 fs/jfs/super.c:223
 generic_shutdown_super+0x144/0x370 fs/super.c:446
 kill_block_super+0x95/0xe0 fs/super.c:1161
 deactivate_locked_super+0x6c/0xd0 fs/super.c:319
 deactivate_super+0x7f/0xa0 fs/super.c:350
 cleanup_mnt+0x186/0x2c0 fs/namespace.c:1183
 task_work_run+0x11f/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

The buggy address belongs to the object at ffff8880aab8b900
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 8 bytes inside of
 192-byte region [ffff8880aab8b900, ffff8880aab8b9c0)
The buggy address belongs to the page:
page:ffffea0002aae2c0 count:1 mapcount:0 mapping:ffff8880aab8b000 index:0xffff8880aab8bf00
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffff8880aab8b000 ffff8880aab8bf00 000000010000000f
raw: ffffea0002a89360 ffffea0002a7b020 ffff88813fe82040 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880aab8b800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880aab8b880: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
>ffff8880aab8b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880aab8b980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880aab8ba00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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