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BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:938 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103
Read of size 8 at addr ffff88804c6103b0 by task kworker/u4:2/56

CPU: 0 PID: 56 Comm: kworker/u4:2 Not tainted 5.6.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: ib_addr process_one_req
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:382
 __kasan_report.cold+0x35/0x4d mm/kasan/report.c:511
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 __mutex_lock_common kernel/locking/mutex.c:938 [inline]
 __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103
 addr_handler+0xa0/0x340 drivers/infiniband/core/cma.c:3100
 process_one_req+0xfa/0x680 drivers/infiniband/core/addr.c:643
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2266
 worker_thread+0x96/0xe20 kernel/workqueue.c:2412
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 12239:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 __rdma_create_id+0x5b/0x850 drivers/infiniband/core/cma.c:861
 ucma_create_id+0x1d1/0x590 drivers/infiniband/core/ucma.c:503
 ucma_write+0x285/0x350 drivers/infiniband/core/ucma.c:1729
 __vfs_write+0x76/0x100 fs/read_write.c:494
 vfs_write+0x268/0x5d0 fs/read_write.c:558
 ksys_write+0x1ee/0x250 fs/read_write.c:611
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 12236:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 kasan_set_free_info mm/kasan/common.c:317 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 ucma_close+0x111/0x300 drivers/infiniband/core/ucma.c:1807
 __fput+0x33e/0x880 fs/file_table.c:280
 task_work_run+0xf4/0x1b0 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff88804c610000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 944 bytes inside of
 2048-byte region [ffff88804c610000, ffff88804c610800)
The buggy address belongs to the page:
page:ffffea0001318400 refcount:1 mapcount:0 mapping:0000000009248fe3 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00025d0948 ffffea000280acc8 ffff8880aa000e00
raw: 0000000000000000 ffff88804c610000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804c610280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804c610300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804c610380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88804c610400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804c610480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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