================================================================== BUG: KASAN: use-after-free in __fib6_clean_all+0x296/0x2a0 net/ipv6/ip6_fib.c:2255 Read of size 8 at addr ffff88814598e000 by task syz-executor.4/3633 CPU: 0 PID: 3633 Comm: syz-executor.4 Not tainted 5.18.0-rc7-syzkaller-00111-g9b80ccda233f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 __fib6_clean_all+0x296/0x2a0 net/ipv6/ip6_fib.c:2255 rt6_sync_down_dev net/ipv6/route.c:4883 [inline] rt6_disable_ip+0x7b7/0x9a0 net/ipv6/route.c:4888 addrconf_ifdown.isra.0+0xf6/0x16b0 net/ipv6/addrconf.c:3738 addrconf_notify+0xeb/0x1ba0 net/ipv6/addrconf.c:3662 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1938 call_netdevice_notifiers_extack net/core/dev.c:1976 [inline] call_netdevice_notifiers net/core/dev.c:1990 [inline] netdev_wait_allrefs_any net/core/dev.c:10141 [inline] netdev_run_todo+0xb90/0x10b0 net/core/dev.c:10253 tun_detach drivers/net/tun.c:696 [inline] tun_chr_close+0xe0/0x180 drivers/net/tun.c:3445 __fput+0x277/0x9d0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:37 [inline] do_exit+0xaff/0x2a00 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+0x44/0xae RIP: 0033:0x7f44a12890e9 Code: Unable to access opcode bytes at RIP 0x7f44a12890bf. RSP: 002b:00007fff4b7f8828 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fff4b7f89d0 RCX: 00007f44a12890e9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043 RBP: 0000000000000000 R08: 0000000000000025 R09: 00007fff4b7f89d0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f44a12e305e R13: 000000000000001c R14: 0000000000000012 R15: 00007fff4b7f8a10 Allocated by task 3633: 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:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:714 [inline] fib6_net_init net/ipv6/ip6_fib.c:2376 [inline] fib6_net_init+0x1d7/0xa20 net/ipv6/ip6_fib.c:2351 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 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3201 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+0x44/0xae Freed by task 1398: 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:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kfree+0xd6/0x4d0 mm/slub.c:4552 fib6_net_exit+0x1c9/0x280 net/ipv6/ip6_fib.c:2438 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:162 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff88814598e000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 0 bytes inside of 2048-byte region [ffff88814598e000, ffff88814598e800) The buggy address belongs to the physical page: page:ffffea0005166200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x145988 head:ffffea0005166200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 ffffea000515c400 dead000000000002 ffff888010c42000 raw: 0000000000000000 0000000000080008 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 3135733217, free_ts 0 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2104 alloc_pages+0x2b1/0x310 mm/mempolicy.c:2267 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] kmem_cache_alloc_trace+0x310/0x3f0 mm/slub.c:3256 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:714 [inline] acpi_os_allocate_zeroed include/acpi/platform/aclinuxex.h:57 [inline] acpi_ds_create_walk_state+0x88/0x1ff drivers/acpi/acpica/dswstate.c:518 acpi_ps_execute_method+0x19d/0x61c drivers/acpi/acpica/psxface.c:134 acpi_ns_evaluate+0x6c7/0x966 drivers/acpi/acpica/nseval.c:205 acpi_ut_evaluate_object+0xf1/0x3f6 drivers/acpi/acpica/uteval.c:60 acpi_ut_execute_STA+0x82/0x17b drivers/acpi/acpica/uteval.c:223 acpi_ns_get_device_callback drivers/acpi/acpica/nsxfeval.c:723 [inline] acpi_ns_get_device_callback+0x11f/0x411 drivers/acpi/acpica/nsxfeval.c:635 acpi_ns_walk_namespace+0x24c/0x42e drivers/acpi/acpica/nswalk.c:240 acpi_get_devices+0xd7/0x12a drivers/acpi/acpica/nsxfeval.c:805 page_owner free stack trace missing Memory state around the buggy address: ffff88814598df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88814598df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88814598e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88814598e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88814598e100: fb fb fb fb fb fb fb fb fb 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