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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 ffff8801bdfecb18 by task syz-executor2/21643

CPU: 0 PID: 21643 Comm: syz-executor2 Not tainted 4.16.0-rc7+ #284
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:1656
 __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_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f81c99
RSP: 002b:00000000f5f7d0ac EFLAGS: 00000282 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 0000000020000040
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 4304:
 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:3608
 kmalloc include/linux/slab.h:512 [inline]
 syslog_print kernel/printk/printk.c:1296 [inline]
 do_syslog+0x5d7/0xb80 kernel/printk/printk.c:1459
 kmsg_read+0x74/0xa0 fs/proc/kmsg.c:40
 proc_reg_read+0xe8/0x160 fs/proc/inode.c:218
 __vfs_read+0xef/0xa00 fs/read_write.c:411
 vfs_read+0x11e/0x350 fs/read_write.c:447
 SYSC_read fs/read_write.c:573 [inline]
 SyS_read+0xef/0x220 fs/read_write.c:566
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 4304:
 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:3486 [inline]
 kfree+0xd9/0x260 mm/slab.c:3801
 syslog_print kernel/printk/printk.c:1347 [inline]
 do_syslog+0x8b5/0xb80 kernel/printk/printk.c:1459
 kmsg_read+0x74/0xa0 fs/proc/kmsg.c:40
 proc_reg_read+0xe8/0x160 fs/proc/inode.c:218
 __vfs_read+0xef/0xa00 fs/read_write.c:411
 vfs_read+0x11e/0x350 fs/read_write.c:447
 SYSC_read fs/read_write.c:573 [inline]
 SyS_read+0xef/0x220 fs/read_write.c:566
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801bdfec940
 which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 472 bytes inside of
 1024-byte region [ffff8801bdfec940, ffff8801bdfecd40)
The buggy address belongs to the page:
page:ffffea0006f7fb00 count:1 mapcount:0 mapping:ffff8801bdfec040 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801bdfec040 0000000000000000 0000000100000007
raw: ffffea0007696ba0 ffffea0006c15120 ffff8801dac00ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801bdfeca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801bdfeca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801bdfecb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8801bdfecb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801bdfecc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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