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BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:47 [inline]
BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0x96/0x670 kernel/locking/mutex.c:1206
Read of size 8 at addr ffff8880993e2298 by task syz-executor.3/18135

CPU: 1 PID: 18135 Comm: syz-executor.3 Not tainted 4.19.107-syzkaller #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+0x188/0x20d lib/dump_stack.c:118
 print_address_description.cold+0x7c/0x212 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x88/0x2b9 mm/kasan/report.c:396
 atomic64_read include/asm-generic/atomic-instrumented.h:27 [inline]
 atomic_long_read include/asm-generic/atomic-long.h:47 [inline]
 __mutex_unlock_slowpath+0x96/0x670 kernel/locking/mutex.c:1206
 blkdev_get+0x561/0x910 fs/block_dev.c:1671
 blkdev_get_by_dev+0x3b/0x70 fs/block_dev.c:1750
 lock_rdev+0x93/0x150 drivers/md/md.c:2307
 md_import_device+0x1fc/0x4a0 drivers/md/md.c:3488
 add_new_disk+0x549/0x17a0 drivers/md/md.c:6347
 md_ioctl+0x3fcb/0x5210 drivers/md/md.c:7365
 __blkdev_driver_ioctl block/ioctl.c:303 [inline]
 blkdev_ioctl+0xbf7/0x1a1c block/ioctl.c:601
 block_ioctl+0xe9/0x130 fs/block_dev.c:1894
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c479
Code: ad 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1b66b15c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1b66b166d4 RCX: 000000000045c479
RDX: 0000000020001200 RSI: 0000000040140921 RDI: 0000000000000009
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000021e R14: 00000000004c4045 R15: 000000000076bf2c

Allocated by task 18135:
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:531
 kmem_cache_alloc+0x127/0x710 mm/slab.c:3559
 bdev_alloc_inode+0x18/0x40 fs/block_dev.c:744
 alloc_inode+0x5d/0x180 fs/inode.c:210
 iget5_locked fs/inode.c:1130 [inline]
 iget5_locked+0x57/0xd0 fs/inode.c:1123
 bdget+0x96/0x510 fs/block_dev.c:885
 blkdev_get_by_dev+0x21/0x70 fs/block_dev.c:1746
 lock_rdev+0x93/0x150 drivers/md/md.c:2307
 md_import_device+0x1fc/0x4a0 drivers/md/md.c:3488
 add_new_disk+0x549/0x17a0 drivers/md/md.c:6347
 md_ioctl+0x3fcb/0x5210 drivers/md/md.c:7365
 __blkdev_driver_ioctl block/ioctl.c:303 [inline]
 blkdev_ioctl+0xbf7/0x1a1c block/ioctl.c:601
 block_ioctl+0xe9/0x130 fs/block_dev.c:1894
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 18132:
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/kasan.c:521
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 __rcu_reclaim kernel/rcu/rcu.h:236 [inline]
 rcu_do_batch kernel/rcu/tree.c:2584 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline]
 rcu_process_callbacks+0xb2d/0x17f0 kernel/rcu/tree.c:2881
 __do_softirq+0x26c/0x93c kernel/softirq.c:292

The buggy address belongs to the object at ffff8880993e2280
 which belongs to the cache bdev_cache(65:syz3) of size 1344
The buggy address is located 24 bytes inside of
 1344-byte region [ffff8880993e2280, ffff8880993e27c0)
The buggy address belongs to the page:
page:ffffea000264f880 count:1 mapcount:0 mapping:ffff888086ac1380 index:0xffff8880993e2ffe
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea00010649c8 ffffea000102e408 ffff888086ac1380
raw: ffff8880993e2ffe ffff8880993e2280 0000000100000002 ffff88804c146780
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff88804c146780

Memory state around the buggy address:
 ffff8880993e2180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880993e2200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880993e2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880993e2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880993e2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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