================================================================== BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline] BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:28 [inline] BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0x9b/0x6b0 kernel/locking/mutex.c:1207 Read of size 8 at addr ffff88801deec718 by task syz-executor.3/17542 CPU: 0 PID: 17542 Comm: syz-executor.3 Not tainted 5.2.0-rc5+ #31 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:94 atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline] atomic_long_read include/asm-generic/atomic-long.h:28 [inline] __mutex_unlock_slowpath+0x9b/0x6b0 kernel/locking/mutex.c:1207 mutex_unlock+0xd/0x10 kernel/locking/mutex.c:714 blkdev_get+0x5a4/0x990 fs/block_dev.c:1707 blkdev_get_by_dev+0x42/0x80 fs/block_dev.c:1786 lock_rdev+0xa0/0x160 drivers/md/md.c:2275 md_import_device+0x221/0x520 drivers/md/md.c:3456 add_new_disk+0x593/0x18c0 drivers/md/md.c:6312 md_ioctl+0x45ce/0x5980 drivers/md/md.c:7330 __blkdev_driver_ioctl block/ioctl.c:304 [inline] blkdev_ioctl+0xece/0x1c10 block/ioctl.c:606 block_ioctl+0xee/0x130 fs/block_dev.c:1930 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f35db64ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 0000000020000040 RSI: 0000000040140921 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f35db64b6d4 R13: 00000000004c085c R14: 00000000004d3368 R15: 00000000ffffffff Allocated by task 17542: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488 bdev_alloc_inode+0x1c/0x50 fs/block_dev.c:784 alloc_inode+0x68/0x1e0 fs/inode.c:227 iget5_locked fs/inode.c:1136 [inline] iget5_locked+0x63/0xe0 fs/inode.c:1129 bdget+0x97/0x550 fs/block_dev.c:917 blkdev_get_by_dev+0x27/0x80 fs/block_dev.c:1782 lock_rdev+0xa0/0x160 drivers/md/md.c:2275 md_import_device+0x221/0x520 drivers/md/md.c:3456 add_new_disk+0x593/0x18c0 drivers/md/md.c:6312 md_ioctl+0x45ce/0x5980 drivers/md/md.c:7330 __blkdev_driver_ioctl block/ioctl.c:304 [inline] blkdev_ioctl+0xece/0x1c10 block/ioctl.c:606 block_ioctl+0xee/0x130 fs/block_dev.c:1930 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 bdev_free_inode+0x20/0x30 fs/block_dev.c:792 i_callback+0x44/0x80 fs/inode.c:216 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c kernel/softirq.c:292 The buggy address belongs to the object at ffff88801deec700 which belongs to the cache bdev_cache(65:syz3) of size 1336 The buggy address is located 24 bytes inside of 1336-byte region [ffff88801deec700, ffff88801deecc38) The buggy address belongs to the page: page:ffffea000077bb00 refcount:1 mapcount:0 mapping:ffff8880678184c0 index:0xffff88801deecffe flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea000141b4c8 ffffea0001406288 ffff8880678184c0 raw: ffff88801deecffe ffff88801deec140 0000000100000002 ffff88805a69a0c0 page dumped because: kasan: bad access detected page->mem_cgroup:ffff88805a69a0c0 Memory state around the buggy address: ffff88801deec600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc ffff88801deec680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801deec700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801deec780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801deec800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================