================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in ip6mr_sk_done+0x139/0x400 net/ipv6/ip6mr.c:1604 Read of size 4 at addr ffff8880460ee888 by task syz-executor.5/12468 CPU: 1 PID: 12468 Comm: syz-executor.5 Not tainted 6.0.0-syzkaller-02770-g79d878f7ad8e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 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:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] ip6mr_sk_done+0x139/0x400 net/ipv6/ip6mr.c:1604 rawv6_close+0x58/0x80 net/ipv6/raw.c:1167 inet_release+0x12e/0x270 net/ipv4/af_inet.c:428 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:482 __sock_release net/socket.c:650 [inline] sock_release+0x87/0x1b0 net/socket.c:678 inet_ctl_sock_destroy include/net/inet_common.h:71 [inline] igmp6_net_exit+0x6b/0x170 net/ipv6/mcast.c:3167 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162 setup_net+0x7fb/0xc50 net/core/net_namespace.c:348 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 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: 0033:0x7f4c10a8b5f9 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:00007f4c11b43118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4c10babf80 RCX: 00007f4c10a8b5f9 RDX: 0000000020000b40 RSI: 0000000020000b30 RDI: 0000000040000000 RBP: 00007f4c10ae67b0 R08: 0000000020000bc0 R09: 0000000020000bc0 R10: 0000000020000b80 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffc068a6bdf R14: 00007f4c11b43300 R15: 0000000000022000 Allocated by task 12468: 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 kmemdup+0x23/0x50 mm/util.c:129 kmemdup include/linux/fortify-string.h:565 [inline] addrconf_init_net+0x1be/0x870 net/ipv6/addrconf.c:7161 ops_init+0xaf/0x470 net/core/net_namespace.c:134 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 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 Freed by task 12468: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:367 [inline] ____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 addrconf_init_net+0x649/0x870 net/ipv6/addrconf.c:7219 ops_init+0xaf/0x470 net/core/net_namespace.c:134 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 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 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x8f0 kernel/rcu/tree.c:3341 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1716 unregister_sysctl_table fs/proc/proc_sysctl.c:1754 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1729 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1441 [inline] mpls_dev_notify+0x5cb/0x9b0 net/mpls/af_mpls.c:1653 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] unregister_netdevice_many+0xa69/0x1980 net/core/dev.c:10843 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1126 ops_exit_list+0x125/0x170 net/core/net_namespace.c:167 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x991/0x1610 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 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x8f0 kernel/rcu/tree.c:3341 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1716 unregister_sysctl_table fs/proc/proc_sysctl.c:1754 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1729 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7112 [inline] addrconf_sysctl_unregister+0xee/0x1c0 net/ipv6/addrconf.c:7140 addrconf_ifdown.isra.0+0x1350/0x1920 net/ipv6/addrconf.c:3903 addrconf_notify+0xeb/0x1c10 net/ipv6/addrconf.c:3673 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] unregister_netdevice_many+0xa69/0x1980 net/core/dev.c:10843 unregister_netdevice_queue+0x2dd/0x3c0 net/core/dev.c:10774 unregister_netdevice include/linux/netdevice.h:3032 [inline] ppp_release+0x216/0x240 drivers/net/ppp/ppp_generic.c:407 __fput+0x277/0x9d0 fs/file_table.c:320 task_work_run+0xdd/0x1a0 kernel/task_work.c:177 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xad5/0x29b0 kernel/exit.c:795 do_group_exit+0xd2/0x2f0 kernel/exit.c:925 __do_sys_exit_group kernel/exit.c:936 [inline] __se_sys_exit_group kernel/exit.c:934 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:934 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 ffff8880460ee800 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 136 bytes inside of 256-byte region [ffff8880460ee800, ffff8880460ee900) The buggy address belongs to the physical page: page:ffffea0001183b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x460ee head:ffffea0001183b80 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001183880 dead000000000003 ffff888011841b40 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3648, tgid 3648 (syz-executor.4), ts 148265659292, free_ts 11549120682 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] slab_alloc mm/slub.c:3256 [inline] __kmalloc+0x32b/0x340 mm/slub.c:4425 kmalloc include/linux/slab.h:605 [inline] kzalloc include/linux/slab.h:733 [inline] new_dir fs/proc/proc_sysctl.c:978 [inline] get_subdir fs/proc/proc_sysctl.c:1022 [inline] __register_sysctl_table+0x9eb/0x10a0 fs/proc/proc_sysctl.c:1373 __addrconf_sysctl_register+0x1db/0x3d0 net/ipv6/addrconf.c:7083 addrconf_sysctl_register net/ipv6/addrconf.c:7130 [inline] addrconf_sysctl_register+0x139/0x1d0 net/ipv6/addrconf.c:7119 ipv6_add_dev+0xade/0x1390 net/ipv6/addrconf.c:450 addrconf_notify+0x6f9/0x1c10 net/ipv6/addrconf.c:3528 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] register_netdevice+0x10bb/0x1670 net/core/dev.c:10086 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:317 [inline] nsim_create+0x3c3/0x520 drivers/net/netdevsim/netdev.c:365 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 free_contig_range+0xb1/0x180 mm/page_alloc.c:9453 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2945/0x29d6 mm/debug_vm_pgtable.c:1354 do_one_initcall+0xfe/0x650 init/main.c:1296 do_initcall_level init/main.c:1369 [inline] do_initcalls init/main.c:1385 [inline] do_basic_setup init/main.c:1404 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1623 kernel_init+0x1a/0x1d0 init/main.c:1512 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff8880460ee780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880460ee800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880460ee880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880460ee900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880460ee980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================