================================================================== BUG: KASAN: use-after-free in nilfs_segctor_confirm+0x175/0x190 fs/nilfs2/segment.c:837 Read of size 8 at addr ffff88807e712230 by task segctord/29993 CPU: 1 PID: 29993 Comm: segctord Not tainted 6.0.0-rc6-next-20220923-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 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 nilfs_segctor_confirm+0x175/0x190 fs/nilfs2/segment.c:837 nilfs_segctor_construct+0x145/0xb30 fs/nilfs2/segment.c:2372 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2481 [inline] nilfs_segctor_thread+0x3c3/0xf30 fs/nilfs2/segment.c:2564 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 29992: 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:559 [inline] kzalloc include/linux/slab.h:695 [inline] nilfs_find_or_create_root+0x84/0x4d0 fs/nilfs2/the_nilfs.c:747 nilfs_attach_checkpoint+0xc1/0x4b0 fs/nilfs2/super.c:519 nilfs_fill_super fs/nilfs2/super.c:1064 [inline] nilfs_mount+0xb12/0xfb0 fs/nilfs2/super.c:1317 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x1326/0x1e20 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 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 29998: 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 nilfs_put_root+0xb1/0xd0 fs/nilfs2/the_nilfs.c:804 nilfs_clear_inode+0x29a/0x330 fs/nilfs2/inode.c:895 nilfs_evict_inode+0x1ee/0x440 fs/nilfs2/inode.c:924 evict+0x2ed/0x6b0 fs/inode.c:664 iput_final fs/inode.c:1747 [inline] iput.part.0+0x59b/0x880 fs/inode.c:1773 iput+0x58/0x70 fs/inode.c:1763 nilfs_new_inode+0x686/0x830 fs/nilfs2/inode.c:394 nilfs_create fs/nilfs2/namei.c:85 [inline] nilfs_create+0xfe/0x300 fs/nilfs2/namei.c:75 lookup_open.isra.0+0xf05/0x12a0 fs/namei.c:3413 open_last_lookups fs/namei.c:3481 [inline] path_openat+0x996/0x28f0 fs/namei.c:3688 do_filp_open+0x1b6/0x400 fs/namei.c:3718 do_sys_openat2+0x16d/0x4c0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1337 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:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 kvfree_call_rcu+0x74/0x8f0 kernel/rcu/tree.c:3341 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1709 unregister_sysctl_table fs/proc/proc_sysctl.c:1747 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1722 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1441 [inline] mpls_dev_notify+0x578/0x920 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+0xaef/0x1a40 net/core/dev.c:10860 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1126 ops_exit_list+0x125/0x170 net/core/net_namespace.c:168 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 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 kvfree_call_rcu+0x74/0x8f0 kernel/rcu/tree.c:3341 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1709 unregister_sysctl_table fs/proc/proc_sysctl.c:1747 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1722 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7112 [inline] addrconf_exit_net+0x172/0x3f0 net/ipv6/addrconf.c:7233 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 The buggy address belongs to the object at ffff88807e712200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of 256-byte region [ffff88807e712200, ffff88807e712300) The buggy address belongs to the physical page: page:ffffea0001f9c480 refcount:1 mapcount:0 mapping:0000000000000000 index:0xdead000000000100 pfn:0x7e712 head:ffffea0001f9c480 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888011841b40 dead000080100010 0000000000000000 raw: dead000000000100 dead000000000122 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 10941, tgid 10935 (syz-executor.1), ts 470303602614, free_ts 470253207029 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x1092/0x2d20 mm/page_alloc.c:4287 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5546 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+0x44/0xc0 mm/slab_common.c:947 kmalloc include/linux/slab.h:564 [inline] kzalloc include/linux/slab.h:695 [inline] new_dir fs/proc/proc_sysctl.c:971 [inline] get_subdir fs/proc/proc_sysctl.c:1015 [inline] __register_sysctl_table+0x9eb/0x10a0 fs/proc/proc_sysctl.c:1366 __addrconf_sysctl_register+0x1db/0x3d0 net/ipv6/addrconf.c:7083 addrconf_init_net+0x517/0x870 net/ipv6/addrconf.c:7202 ops_init+0xaf/0x470 net/core/net_namespace.c:135 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 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 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2532 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x62/0x80 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:754 [inline] slab_alloc_node mm/slub.c:3336 [inline] __kmem_cache_alloc_node+0x2d2/0x3d0 mm/slub.c:3375 __do_kmalloc_node mm/slab_common.c:933 [inline] __kmalloc+0x44/0xc0 mm/slab_common.c:947 kmalloc include/linux/slab.h:564 [inline] kzalloc include/linux/slab.h:695 [inline] tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45 tomoyo_encode2 security/tomoyo/realpath.c:31 [inline] tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x368/0x400 security/tomoyo/file.c:831 tomoyo_path_symlink+0x94/0xe0 security/tomoyo/tomoyo.c:199 security_path_symlink+0xdf/0x150 security/security.c:1182 do_symlinkat+0x106/0x2e0 fs/namei.c:4402 __do_sys_symlinkat fs/namei.c:4424 [inline] __se_sys_symlinkat fs/namei.c:4421 [inline] __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4421 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88807e712100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e712180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e712200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e712280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e712300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================