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BUG: KASAN: use-after-free in __list_add_valid+0xc6/0xd0 lib/list_debug.c:26
Read of size 8 at addr ffff8801d00fc218 by task syz-executor6/6125

CPU: 1 PID: 6125 Comm: syz-executor6 Not tainted 4.16.0-rc6+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __list_add_valid+0xc6/0xd0 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:2309 [inline]
 rdma_listen+0x581/0x8e0 drivers/infiniband/core/cma.c:3333
 ucma_listen+0x172/0x1f0 drivers/infiniband/core/ucma.c:1074
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1649
 __vfs_write+0xef/0x970 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454879
RSP: 002b:00007fa618b8ec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa618b8f6d4 RCX: 0000000000454879
RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000683 R14: 00000000006face8 R15: 0000000000000000

Allocated by task 6125:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 kmem_cache_alloc_trace+0x136/0x740 mm/slab.c:3607
 kmalloc include/linux/slab.h:512 [inline]
 kzalloc include/linux/slab.h:701 [inline]
 rdma_create_id+0xd0/0x630 drivers/infiniband/core/cma.c:787
 ucma_create_id+0x35f/0x920 drivers/infiniband/core/ucma.c:480
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1649
 __vfs_write+0xef/0x970 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 6125:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3485 [inline]
 kfree+0xd9/0x260 mm/slab.c:3800
 rdma_destroy_id+0x821/0xda0 drivers/infiniband/core/cma.c:1691
 ucma_close+0x100/0x2f0 drivers/infiniband/core/ucma.c:1728
 __fput+0x327/0x7e0 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x199/0x270 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x275/0x2f0 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x6ec/0x940 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801d00fc040
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 472 bytes inside of
 1024-byte region [ffff8801d00fc040, ffff8801d00fc440)
The buggy address belongs to the page:
page:ffffea0007403f00 count:1 mapcount:0 mapping:ffff8801d00fc040 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801d00fc040 0000000000000000 0000000100000007
raw: ffffea0007411ea0 ffffea00073b3c20 ffff8801dac00ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d00fc100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d00fc180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d00fc200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8801d00fc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801d00fc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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