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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 ffff888054f957a0 by task syz-executor.3/7033

CPU: 1 PID: 7033 Comm: syz-executor.3 Not tainted 5.0.0+ #14
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __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:2477 [inline]
 rdma_listen+0x63b/0x8e0 drivers/infiniband/core/cma.c:3492
 ucma_listen+0x14d/0x1c0 drivers/infiniband/core/ucma.c:1100
 ucma_write+0x2da/0x3c0 drivers/infiniband/core/ucma.c:1689
 __vfs_write+0x8d/0x110 fs/read_write.c:485
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0xea/0x1f0 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457f29
Code: ad b8 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 b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f77baa9cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457f29
RDX: 00000000ffffff3a RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77baa9d6d4
R13: 00000000004c71d9 R14: 00000000004dcc90 R15: 00000000ffffffff

Allocated by task 13653:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505
 slab_post_alloc_hook mm/slab.h:436 [inline]
 slab_alloc mm/slab.c:3392 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3554
 getname_flags fs/namei.c:138 [inline]
 getname_flags+0xd6/0x5b0 fs/namei.c:128
 user_path_at_empty+0x2f/0x50 fs/namei.c:2606
 do_readlinkat+0xe9/0x320 fs/stat.c:397
 __do_sys_readlink fs/stat.c:430 [inline]
 __se_sys_readlink fs/stat.c:427 [inline]
 __x64_sys_readlink+0x78/0xb0 fs/stat.c:427
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 13653:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3764
 putname+0xef/0x130 fs/namei.c:259
 filename_lookup+0x28f/0x410 fs/namei.c:2355
 user_path_at_empty+0x43/0x50 fs/namei.c:2606
 do_readlinkat+0xe9/0x320 fs/stat.c:397
 __do_sys_readlink fs/stat.c:430 [inline]
 __se_sys_readlink fs/stat.c:427 [inline]
 __x64_sys_readlink+0x78/0xb0 fs/stat.c:427
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888054f949c0
 which belongs to the cache names_cache of size 4096
The buggy address is located 3552 bytes inside of
 4096-byte region [ffff888054f949c0, ffff888054f959c0)
The buggy address belongs to the page:
page:ffffea000153e500 count:1 mapcount:0 mapping:ffff88812c2c5dc0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0001564d08 ffffea00024bb608 ffff88812c2c5dc0
raw: 0000000000000000 ffff888054f949c0 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888054f95680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888054f95700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888054f95780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff888054f95800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888054f95880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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IPVS: ftp: loaded support on port[0] = 21