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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 ffff888099b496e0 by task syz-executor.0/27381

CPU: 1 PID: 27381 Comm: syz-executor.0 Not tainted 4.19.89-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.cold+0x7c/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __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:2380 [inline]
 rdma_listen+0x63b/0x8e0 drivers/infiniband/core/cma.c:3408
 ucma_listen+0x14d/0x1c0 drivers/infiniband/core/ucma.c:1100
 ucma_write+0x2d7/0x3c0 drivers/infiniband/core/ucma.c:1689
 __vfs_write+0x114/0x810 fs/read_write.c:485
 vfs_write+0x20c/0x560 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
audit: type=1400 audit(2000000660.340:300): avc:  denied  { map } for  pid=27523 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a909
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:00007f0e8a59ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a909
RDX: 00000000000000c1 RSI: 0000000020000040 RDI: 0000000000000005
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0e8a59f6d4
R13: 00000000004cbc11 R14: 00000000004e57b8 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea000266d240 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000000()
raw: 00fffe0000000000 0000000000000000 ffffffff02660101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888099b49580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888099b49600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888099b49680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                       ^
 ffff888099b49700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888099b49780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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