===================================== WARNING: bad unlock balance detected! 5.6.0-rc3-syzkaller #0 Not tainted ------------------------------------- syz-executor.0/11452 is trying to release lock ( ================================================================== BUG: KASAN: use-after-free in print_unlock_imbalance_bug kernel/locking/lockdep.c:3999 [inline] BUG: KASAN: use-after-free in print_unlock_imbalance_bug.cold+0x97/0x123 kernel/locking/lockdep.c:3983 Read of size 8 at addr ffff88809d32ca60 by task syz-executor.0/11452 CPU: 0 PID: 11452 Comm: syz-executor.0 Not tainted 5.6.0-rc3-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+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:641 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135 print_unlock_imbalance_bug kernel/locking/lockdep.c:3999 [inline] print_unlock_imbalance_bug.cold+0x97/0x123 kernel/locking/lockdep.c:3983 __lock_release kernel/locking/lockdep.c:4241 [inline] lock_release+0x5f2/0x960 kernel/locking/lockdep.c:4502 __mutex_unlock_slowpath+0x86/0x6a0 kernel/locking/mutex.c:1228 mutex_unlock+0xd/0x10 kernel/locking/mutex.c:740 ucma_destroy_id+0x24a/0x490 drivers/infiniband/core/ucma.c:621 ucma_write+0x2d7/0x3c0 drivers/infiniband/core/ucma.c:1684 __vfs_write+0x8a/0x110 fs/read_write.c:494 vfs_write+0x268/0x5d0 fs/read_write.c:558 ksys_write+0x220/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 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:00007f36a9ea4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f36a9ea56d4 RCX: 000000000045c449 RDX: 0000000000000018 RSI: 0000000020000200 RDI: 0000000000000006 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000cb7 R14: 00000000004d7b10 R15: 000000000076bf2c Allocated by task 11457: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:515 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] ucma_open+0x4f/0x290 drivers/infiniband/core/ucma.c:1716 misc_open+0x395/0x4c0 drivers/char/misc.c:141 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x12ee/0x3490 fs/namei.c:3607 do_filp_open+0x192/0x260 fs/namei.c:3637 do_sys_openat2+0x5eb/0x7e0 fs/open.c:1149 do_sys_open+0xf2/0x180 fs/open.c:1165 __do_sys_openat fs/open.c:1179 [inline] __se_sys_openat fs/open.c:1174 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1174 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 11451: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 ucma_close+0x275/0x310 drivers/infiniband/core/ucma.c:1772 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88809d32ca00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 96 bytes inside of 256-byte region [ffff88809d32ca00, ffff88809d32cb00) The buggy address belongs to the page: page:ffffea000274cb00 refcount:1 mapcount:0 mapping:ffff8880aa4008c0 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00025e7e88 ffffea0002671d88 ffff8880aa4008c0 raw: 0000000000000000 ffff88809d32c000 0000000100000008 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809d32c900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809d32c980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809d32ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809d32ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809d32cb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================