================================================================== BUG: KASAN: use-after-free in __fib6_clean_all+0x296/0x2a0 net/ipv6/ip6_fib.c:2255 Read of size 8 at addr ffff8881456ac000 by task syz-executor.3/3646 CPU: 1 PID: 3646 Comm: syz-executor.3 Not tainted 6.1.0-rc4-syzkaller-00159-g4bbf3422df78 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 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:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 __fib6_clean_all+0x296/0x2a0 net/ipv6/ip6_fib.c:2255 rt6_sync_down_dev net/ipv6/route.c:4894 [inline] rt6_disable_ip+0x803/0x9f0 net/ipv6/route.c:4899 addrconf_ifdown.isra.0+0x11a/0x1920 net/ipv6/addrconf.c:3750 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] netdev_wait_allrefs_any net/core/dev.c:10237 [inline] netdev_run_todo+0xbc2/0x1100 net/core/dev.c:10351 tun_detach drivers/net/tun.c:704 [inline] tun_chr_close+0xe0/0x180 drivers/net/tun.c:3467 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16b/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb35/0x2a20 kernel/exit.c:820 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 __do_sys_exit_group kernel/exit.c:961 [inline] __se_sys_exit_group kernel/exit.c:959 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:959 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: 0033:0x7f6e4cc8b639 Code: Unable to access opcode bytes at 0x7f6e4cc8b60f. RSP: 002b:00007ffe56b15bf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007ffe56b15da0 RCX: 00007f6e4cc8b639 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043 RBP: 0000000000000000 R08: 0000000000000025 R09: 00007ffe56b15da0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6e4cce67b2 R13: 000000000000001c R14: 0000000000000014 R15: 00007ffe56b15de0 Allocated by task 3646: 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 kmalloc include/linux/slab.h:553 [inline] kzalloc include/linux/slab.h:689 [inline] fib6_net_init net/ipv6/ip6_fib.c:2376 [inline] fib6_net_init+0x1d7/0xa20 net/ipv6/ip6_fib.c:2351 ops_init+0xb9/0x680 net/core/net_namespace.c:135 setup_net+0x5d1/0xc50 net/core/net_namespace.c:332 copy_net_ns+0x318/0x760 net/core/net_namespace.c:478 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:3188 __do_sys_unshare kernel/fork.c:3259 [inline] __se_sys_unshare kernel/fork.c:3257 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3257 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 16937: 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:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xab/0x3b0 mm/slub.c:3674 fib6_net_exit+0x1c9/0x280 net/ipv6/ip6_fib.c:2438 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:169 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:601 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 The buggy address belongs to the object at ffff8881456ac000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 0 bytes inside of 2048-byte region [ffff8881456ac000, ffff8881456ac800) The buggy address belongs to the physical page: page:ffffea000515aa00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1456a8 head:ffffea000515aa00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 dead000000000100 dead000000000122 ffff888011842000 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 2609308930, free_ts 0 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4288 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5555 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2118 alloc_pages+0x22f/0x270 mm/mempolicy.c:2280 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x191/0x3e0 mm/slub.c:3437 kmalloc_trace+0x22/0x60 mm/slab_common.c:1045 kmalloc include/linux/slab.h:553 [inline] kzalloc include/linux/slab.h:689 [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_ds_call_control_method+0xda/0x56f drivers/acpi/acpica/dsmethod.c:498 acpi_ps_parse_aml+0x2e5/0x8cc drivers/acpi/acpica/psparse.c:503 acpi_ps_execute_method+0x5a7/0x61c drivers/acpi/acpica/psxface.c:190 acpi_ns_evaluate+0x6c7/0x966 drivers/acpi/acpica/nseval.c:205 acpi_ut_evaluate_object+0xf1/0x3f6 drivers/acpi/acpica/uteval.c:60 acpi_rs_get_method_data+0x7e/0xe5 drivers/acpi/acpica/rsutils.c:650 page_owner free stack trace missing Memory state around the buggy address: ffff8881456abf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881456abf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881456ac000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881456ac080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881456ac100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================