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BUG: KASAN: use-after-free in __list_add_valid+0x9a/0xa0 lib/list_debug.c:26
Read of size 8 at addr ffff8880956e31e0 by task syz-executor.1/26571

CPU: 1 PID: 26571 Comm: syz-executor.1 Not tainted 5.4.0-rc8-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/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:634
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 __list_add_valid+0x9a/0xa0 lib/list_debug.c:26
 __list_add include/linux/list.h:60 [inline]
 list_add_tail include/linux/list.h:93 [inline]
 cma_listen_on_all drivers/infiniband/core/cma.c:2509 [inline]
 rdma_listen+0x6b7/0x970 drivers/infiniband/core/cma.c:3563
 ucma_listen+0x14d/0x1c0 drivers/infiniband/core/ucma.c:1092
 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]
 __ia32_sys_write+0x71/0xb0 fs/read_write.c:620
 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
 do_fast_syscall_32+0x27b/0xdb3 arch/x86/entry/common.c:404
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7ffda39
Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5df90cc EFLAGS: 00000296 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200001c0
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 26354:
 save_stack+0x23/0x90 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc mm/kasan/common.c:510 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524
 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3550
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:690 [inline]
 __rdma_create_id+0x5f/0x4e0 drivers/infiniband/core/cma.c:882
 ucma_create_id+0x1de/0x620 drivers/infiniband/core/ucma.c:501
 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]
 __ia32_sys_write+0x71/0xb0 fs/read_write.c:620
 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline]
 do_fast_syscall_32+0x27b/0xdb3 arch/x86/entry/common.c:404
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 26356:
 save_stack+0x23/0x90 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480
 __cache_free mm/slab.c:3425 [inline]
 kfree+0x10a/0x2c0 mm/slab.c:3756
 rdma_destroy_id+0x719/0xaa0 drivers/infiniband/core/cma.c:1877
 ucma_close+0x115/0x310 drivers/infiniband/core/ucma.c:1762
 __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
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x904/0x2e60 kernel/exit.c:817
 do_group_exit+0x135/0x360 kernel/exit.c:921
 get_signal+0x47c/0x2500 kernel/signal.c:2734
 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath+0x47a/0x530 arch/x86/entry/common.c:274
 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:344

The buggy address belongs to the object at ffff8880956e3000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 480 bytes inside of
 2048-byte region [ffff8880956e3000, ffff8880956e3800)
The buggy address belongs to the page:
page:ffffea000255b8c0 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0
raw: 01fffc0000000200 ffffea000293a488 ffffea0002a04dc8 ffff8880aa400e00
raw: 0000000000000000 ffff8880956e3000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880956e3080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880956e3100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880956e3180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff8880956e3200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880956e3280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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