================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0xe8/0x110 lib/list_debug.c:62 Read of size 8 at addr ffff88806ca675d0 by task kworker/u4:0/3691 CPU: 0 PID: 3691 Comm: kworker/u4:0 Not tainted 6.0.0-rc6-next-20220921-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2022 Workqueue: netns cleanup_net Call Trace: __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:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 __list_del_entry_valid+0xe8/0x110 lib/list_debug.c:62 __list_del_entry include/linux/list.h:134 [inline] list_del include/linux/list.h:148 [inline] unregister_shrinker mm/vmscan.c:747 [inline] unregister_shrinker+0x83/0x2f0 mm/vmscan.c:741 nfsd_reply_cache_shutdown+0x22/0x280 fs/nfsd/nfscache.c:210 nfsd_exit_net+0x110/0x4c0 fs/nfsd/nfsctl.c:1507 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:163 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:595 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 3956: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa1/0xb0 mm/kasan/common.c:380 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:934 [inline] __kmalloc+0x54/0xc0 mm/slab_common.c:947 kmalloc include/linux/slab.h:564 [inline] kzalloc include/linux/slab.h:695 [inline] ops_init+0xfb/0x470 net/core/net_namespace.c:125 setup_net+0x5d1/0xc50 net/core/net_namespace.c:326 copy_net_ns+0x318/0x760 net/core/net_namespace.c:472 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x306e/0x71b0 kernel/fork.c:2259 kernel_clone+0xe7/0x980 kernel/fork.c:2676 __do_sys_clone3+0x1cd/0x2e0 kernel/fork.c:2975 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 Freed by task 3956: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1669 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1695 slab_free mm/slub.c:3599 [inline] __kmem_cache_free+0xab/0x3b0 mm/slub.c:3612 ops_init+0xcd/0x470 net/core/net_namespace.c:140 setup_net+0x5d1/0xc50 net/core/net_namespace.c:326 copy_net_ns+0x318/0x760 net/core/net_namespace.c:472 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x306e/0x71b0 kernel/fork.c:2259 kernel_clone+0xe7/0x980 kernel/fork.c:2676 __do_sys_clone3+0x1cd/0x2e0 kernel/fork.c:2975 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 ffff88806ca67000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1488 bytes inside of 2048-byte region [ffff88806ca67000, ffff88806ca67800) The buggy address belongs to the physical page: page:ffffea0001b29800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffea0001b29200 pfn:0x6ca60 head:ffffea0001b29800 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888011842000 dead000000080008 0000000000000000 raw: ffffea0001b29200 dead000000000002 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 2271, tgid 2271 (kworker/1:2), ts 417931299043, free_ts 12501034382 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x1092/0x2d20 mm/page_alloc.c:4286 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5545 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2280 alloc_slab_page mm/slub.c:1739 [inline] allocate_slab+0x213/0x300 mm/slub.c:1884 new_slab mm/slub.c:1937 [inline] ___slab_alloc+0xac1/0x1430 mm/slub.c:3119 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3217 slab_alloc_node mm/slub.c:3302 [inline] __kmem_cache_alloc_node+0x18a/0x3d0 mm/slub.c:3375 __do_kmalloc_node mm/slab_common.c:933 [inline] __kmalloc_node_track_caller+0x45/0xc0 mm/slab_common.c:954 kmalloc_reserve net/core/skbuff.c:362 [inline] __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:434 alloc_skb include/linux/skbuff.h:1258 [inline] alloc_skb_with_frags+0x93/0x6c0 net/core/skbuff.c:6022 sock_alloc_send_pskb+0x7a3/0x930 net/core/sock.c:2719 sock_alloc_send_skb include/net/sock.h:1889 [inline] mld_newpack.isra.0+0x1b9/0x770 net/ipv6/mcast.c:1748 add_grhead+0x295/0x340 net/ipv6/mcast.c:1851 add_grec+0x1082/0x1560 net/ipv6/mcast.c:1989 mld_send_cr net/ipv6/mcast.c:2115 [inline] mld_ifc_work+0x452/0xdc0 net/ipv6/mcast.c:2653 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1458 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3482 free_contig_range+0xb1/0x180 mm/page_alloc.c:9467 destroy_args+0xa8/0x64c mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2954/0x29e5 mm/debug_vm_pgtable.c:1354 do_one_initcall+0x13d/0x780 init/main.c:1307 do_initcall_level init/main.c:1382 [inline] do_initcalls init/main.c:1398 [inline] do_basic_setup init/main.c:1417 [inline] kernel_init_freeable+0x6ff/0x788 init/main.c:1637 kernel_init+0x1a/0x1d0 init/main.c:1525 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff88806ca67480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806ca67500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806ca67580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806ca67600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806ca67680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================