================================================================== BUG: KASAN: use-after-free in notifier_call_chain kernel/notifier.c:72 [inline] BUG: KASAN: use-after-free in raw_notifier_call_chain+0x3e/0x170 kernel/notifier.c:392 Read of size 8 at addr ffff88807a840268 by task syz-executor.0/3606 CPU: 0 PID: 3606 Comm: syz-executor.0 Not tainted 5.18.0-syzkaller #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+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description+0x65/0x4b0 mm/kasan/report.c:313 print_report+0xf4/0x210 mm/kasan/report.c:429 kasan_report+0xfb/0x130 mm/kasan/report.c:491 notifier_call_chain kernel/notifier.c:72 [inline] raw_notifier_call_chain+0x3e/0x170 kernel/notifier.c:392 call_netdevice_notifiers_info net/core/dev.c:1935 [inline] 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+0x8ae/0x1070 net/core/dev.c:10253 tun_detach drivers/net/tun.c:696 [inline] tun_chr_close+0x11f/0x130 drivers/net/tun.c:3445 __fput+0x3b9/0x820 fs/file_table.c:317 task_work_run+0x146/0x1c0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:37 [inline] do_exit+0x547/0x1eb0 kernel/exit.c:795 do_group_exit+0x23b/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+0x3b/0x40 kernel/exit.c:934 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f7b7d2890e9 Code: Unable to access opcode bytes at RIP 0x7f7b7d2890bf. RSP: 002b:00007fffb0084788 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000064 RCX: 00007f7b7d2890e9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00007f7b7d2e226a R08: 000000000000000c R09: 00005555556ae3b8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000016 R13: 00007fffb0085a60 R14: 00005555556ae3b8 R15: 00007fffb0086b60 Allocated by task 3606: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0xb2/0xe0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x199/0x2f0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x13c/0x5b0 net/core/net_namespace.c:458 create_new_namespaces+0x4db/0x8e0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57f/0xb30 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 949: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0xd8/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kmem_cache_free+0xc7/0x270 mm/slub.c:3527 net_free net/core/net_namespace.c:432 [inline] cleanup_net+0xb8b/0xc50 net/core/net_namespace.c:615 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:348 insert_work+0x54/0x3e0 kernel/workqueue.c:1358 __queue_work+0x969/0xc20 kernel/workqueue.c:1517 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers+0x7a2/0x980 kernel/time/timer.c:1737 __do_softirq+0x382/0x793 kernel/softirq.c:558 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:348 insert_work+0x54/0x3e0 kernel/workqueue.c:1358 __queue_work+0x969/0xc20 kernel/workqueue.c:1517 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers+0x7a2/0x980 kernel/time/timer.c:1737 __do_softirq+0x382/0x793 kernel/softirq.c:558 The buggy address belongs to the object at ffff88807a840000 which belongs to the cache net_namespace of size 6784 The buggy address is located 616 bytes inside of 6784-byte region [ffff88807a840000, ffff88807a841a80) The buggy address belongs to the physical page: page:ffffea0001ea1000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807a841b80 pfn:0x7a840 head:ffffea0001ea1000 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88806e8f7301 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888140007500 raw: ffff88807a841b80 0000000080040002 00000001ffffffff ffff88806e8f7301 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 3606, tgid 3606 (syz-executor.0), ts 77229530544, free_ts 77161208976 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0x72e/0x7a0 mm/page_alloc.c:4182 __alloc_pages+0x26c/0x5f0 mm/page_alloc.c:5408 alloc_slab_page+0x70/0xf0 mm/slub.c:1799 allocate_slab+0x5e/0x560 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x41e/0xcd0 mm/slub.c:3005 __slab_alloc mm/slub.c:3092 [inline] slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x246/0x2f0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x13c/0x5b0 net/core/net_namespace.c:458 create_new_namespaces+0x4db/0x8e0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57f/0xb30 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x812/0x900 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x7d/0x390 mm/page_alloc.c:3423 free_slab mm/slub.c:2043 [inline] discard_slab mm/slub.c:2049 [inline] __unfreeze_partials+0x1ab/0x200 mm/slub.c:2523 put_cpu_partial+0x116/0x180 mm/slub.c:2599 do_slab_free mm/slub.c:3498 [inline] ___cache_free+0x118/0x1a0 mm/slub.c:3517 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x1bd/0x370 mm/slub.c:4410 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xd8/0x5f0 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x270/0x6b0 security/tomoyo/file.c:822 security_inode_getattr+0xc0/0x140 security/security.c:1350 vfs_getattr+0x26/0x360 fs/stat.c:157 vfs_statx+0x183/0x3f0 fs/stat.c:232 vfs_fstatat fs/stat.c:255 [inline] __do_sys_newfstatat fs/stat.c:425 [inline] __se_sys_newfstatat+0xf6/0x790 fs/stat.c:419 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88807a840100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807a840180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807a840200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807a840280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807a840300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================