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BUG: KASAN: out-of-bounds in __list_add_valid+0xa5/0xb0 lib/list_debug.c:30
Read of size 8 at addr ffff8880400cd5c8 by task syz-executor.3/20106

CPU: 1 PID: 20106 Comm: syz-executor.3 Not tainted 6.0.0-syzkaller-02739-g60df8c4d32d4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:317 [inline]
 print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
 __list_add_valid+0xa5/0xb0 lib/list_debug.c:30
 __list_add include/linux/list.h:69 [inline]
 list_add_tail include/linux/list.h:102 [inline]
 register_shrinker_prepared+0x37/0x120 mm/vmscan.c:684
 sget_fc+0x5e7/0x7c0 fs/super.c:581
 vfs_get_super fs/super.c:1163 [inline]
 get_tree_nodev+0x24/0x1d0 fs/super.c:1198
 mqueue_get_tree+0xee/0x130 ipc/mqueue.c:435
 vfs_get_tree+0x89/0x2f0 fs/super.c:1530
 fc_mount+0x13/0xc0 fs/namespace.c:1043
 mq_create_mount ipc/mqueue.c:485 [inline]
 mq_init_ns+0x43e/0x630 ipc/mqueue.c:1701
 create_ipc_ns ipc/namespace.c:58 [inline]
 copy_ipcs+0x35e/0x5e0 ipc/namespace.c:94
 create_new_namespaces+0x210/0xb20 kernel/nsproxy.c:90
 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178
 copy_process+0x304d/0x7090 kernel/fork.c:2257
 kernel_clone+0xe7/0xab0 kernel/fork.c:2671
 __do_sys_clone+0xba/0x100 kernel/fork.c:2805
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8b1f08a5a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8b2028d118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f8b1f1ac050 RCX: 00007f8b1f08a5a9
RDX: 0000000020000200 RSI: 00000000200001c0 RDI: 000000000c000000
RBP: 00007f8b1f0e5580 R08: 0000000020000300 R09: 0000000020000300
R10: 0000000020000240 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffe929f7c8f R14: 00007f8b2028d300 R15: 0000000000022000
 </TASK>

Allocated by task 20104:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 ____kasan_kmalloc mm/kasan/common.c:516 [inline]
 ____kasan_kmalloc mm/kasan/common.c:475 [inline]
 __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
 kmalloc_reserve net/core/skbuff.c:437 [inline]
 __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:509
 alloc_skb include/linux/skbuff.h:1265 [inline]
 __ip6_append_data.isra.0+0x3183/0x4410 net/ipv6/ip6_output.c:1679
 ip6_make_skb+0x2a2/0x510 net/ipv6/ip6_output.c:2045
 udpv6_sendmsg+0x2095/0x2c70 net/ipv6/udp.c:1558
 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:653
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2482
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
 __sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff8880400cd000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1480 bytes inside of
 2048-byte region [ffff8880400cd000, ffff8880400cd800)

The buggy address belongs to the physical page:
page:ffffea0001003200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x400c8
head:ffffea0001003200 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888011842000
raw: 0000000000000000 0000000080080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 18394, tgid 18389 (syz-executor.2), ts 442301619763, free_ts 442204614040
 prep_new_page mm/page_alloc.c:2532 [inline]
 get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283
 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549
 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:1829 [inline]
 allocate_slab+0x27e/0x3d0 mm/slub.c:1974
 new_slab mm/slub.c:2034 [inline]
 ___slab_alloc+0x84f/0xe80 mm/slub.c:3036
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123
 slab_alloc_node mm/slub.c:3214 [inline]
 __kmalloc_node_track_caller+0x2f1/0x390 mm/slub.c:4964
 kmalloc_reserve net/core/skbuff.c:437 [inline]
 __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:509
 alloc_skb include/linux/skbuff.h:1265 [inline]
 __ip6_append_data.isra.0+0x3183/0x4410 net/ipv6/ip6_output.c:1679
 ip6_make_skb+0x2a2/0x510 net/ipv6/ip6_output.c:2045
 udpv6_sendmsg+0x2095/0x2c70 net/ipv6/udp.c:1558
 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:653
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2482
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
 __sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1449 [inline]
 free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499
 free_unref_page_prepare mm/page_alloc.c:3380 [inline]
 free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476
 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2553
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:727 [inline]
 slab_alloc_node mm/slub.c:3248 [inline]
 slab_alloc mm/slub.c:3256 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3263 [inline]
 kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3273
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139
 getname_flags include/linux/audit.h:320 [inline]
 getname fs/namei.c:218 [inline]
 __do_sys_unlink fs/namei.c:4345 [inline]
 __se_sys_unlink fs/namei.c:4343 [inline]
 __x64_sys_unlink+0xb1/0x110 fs/namei.c:4343
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff8880400cd480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880400cd500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880400cd580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                 ^
 ffff8880400cd600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880400cd680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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