Hello, syzbot found the following issue on: HEAD commit: fdf0eaf11452 Linux 6.5-rc2 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11354edca80000 kernel config: https://syzkaller.appspot.com/x/.config?x=a4507c291b5ab5d4 dashboard link: https://syzkaller.appspot.com/bug?extid=74db8b3087f293d3a13a compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/227b5c9aa7b3/disk-fdf0eaf1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/aedc7f03bef6/vmlinux-fdf0eaf1.xz kernel image: https://storage.googleapis.com/syzbot-assets/ec543f1fd878/bzImage-fdf0eaf1.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+74db8b3087f293d3a13a@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in nilfs_load_inode_block+0x11e/0x280 fs/nilfs2/inode.c:1030 Read of size 8 at addr ffff888023e50230 by task syz-executor.2/5056 CPU: 1 PID: 5056 Comm: syz-executor.2 Not tainted 6.5.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 nilfs_load_inode_block+0x11e/0x280 fs/nilfs2/inode.c:1030 __nilfs_mark_inode_dirty+0xa5/0x280 fs/nilfs2/inode.c:1107 nilfs_dirty_inode+0x164/0x200 fs/nilfs2/inode.c:1148 __mark_inode_dirty+0x305/0xd90 fs/fs-writeback.c:2430 mark_inode_dirty_sync include/linux/fs.h:2153 [inline] iput+0x1f2/0x8f0 fs/inode.c:1814 nilfs_dispose_list+0x51d/0x5c0 fs/nilfs2/segment.c:816 nilfs_detach_log_writer+0xaf1/0xbb0 fs/nilfs2/segment.c:2859 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:498 generic_shutdown_super+0x134/0x340 fs/super.c:499 kill_block_super+0x68/0xa0 fs/super.c:1417 deactivate_locked_super+0xa4/0x110 fs/super.c:330 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1254 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f723027de57 Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffe73394f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f723027de57 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffe73395010 RBP: 00007ffe73395010 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe733960d0 R13: 00007f72302c73b9 R14: 0000000000032737 R15: 000000000000000c </TASK> Allocated by task 5412: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] nilfs_find_or_create_root+0x137/0x4e0 fs/nilfs2/the_nilfs.c:851 nilfs_attach_checkpoint+0x123/0x4d0 fs/nilfs2/super.c:550 nilfs_fill_super+0x321/0x600 fs/nilfs2/super.c:1095 nilfs_mount+0x637/0x950 fs/nilfs2/super.c:1343 legacy_get_tree+0xef/0x190 fs/fs_context.c:611 vfs_get_tree+0x8c/0x270 fs/super.c:1519 do_new_mount+0x28f/0xae0 fs/namespace.c:3335 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5056: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1792 [inline] slab_free_freelist_hook mm/slub.c:1818 [inline] slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3814 nilfs_segctor_destroy fs/nilfs2/segment.c:2782 [inline] nilfs_detach_log_writer+0x8c1/0xbb0 fs/nilfs2/segment.c:2845 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:498 generic_shutdown_super+0x134/0x340 fs/super.c:499 kill_block_super+0x68/0xa0 fs/super.c:1417 deactivate_locked_super+0xa4/0x110 fs/super.c:330 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1254 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888023e50200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of freed 256-byte region [ffff888023e50200, ffff888023e50300) The buggy address belongs to the physical page: page:ffffea00008f9400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23e50 head:ffffea00008f9400 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888012841b40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 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 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5181, tgid 5181 (syz-executor.2), ts 197741582486, free_ts 196828318372 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1570 prep_new_page mm/page_alloc.c:1577 [inline] get_page_from_freelist+0x31e8/0x3370 mm/page_alloc.c:3221 __alloc_pages+0x255/0x670 mm/page_alloc.c:4477 alloc_slab_page+0x6a/0x160 mm/slub.c:1862 allocate_slab mm/slub.c:2009 [inline] new_slab+0x84/0x2f0 mm/slub.c:2062 ___slab_alloc+0xade/0x1100 mm/slub.c:3215 __slab_alloc mm/slub.c:3314 [inline] __slab_alloc_node mm/slub.c:3367 [inline] slab_alloc_node mm/slub.c:3460 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3509 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1076 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] smk_fetch+0x92/0x140 security/smack/smack_lsm.c:291 smack_d_instantiate+0x868/0xb40 security/smack/smack_lsm.c:3541 security_d_instantiate+0x9b/0xf0 security/security.c:3760 d_instantiate_new+0x65/0x120 fs/dcache.c:2053 ext4_add_nondir+0x22d/0x290 fs/ext4/namei.c:2797 ext4_symlink+0x908/0xb30 fs/ext4/namei.c:3431 vfs_symlink+0x12f/0x2a0 fs/namei.c:4477 do_symlinkat+0x201/0x610 fs/namei.c:4503 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1161 [inline] free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2348 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2443 discard_slab mm/slub.c:2108 [inline] __unfreeze_partials+0x1dc/0x220 mm/slub.c:2647 put_cpu_partial+0x116/0x180 mm/slub.c:2723 __slab_free+0x2b6/0x390 mm/slub.c:3671 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook+0x6c/0x3b0 mm/slab.h:762 slab_alloc_node mm/slub.c:3470 [inline] __kmem_cache_alloc_node+0x141/0x270 mm/slub.c:3509 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1076 kmalloc include/linux/slab.h:582 [inline] kzalloc include/linux/slab.h:703 [inline] mca_alloc net/ipv6/mcast.c:880 [inline] __ipv6_dev_mc_inc+0x426/0xa80 net/ipv6/mcast.c:936 addrconf_join_solict net/ipv6/addrconf.c:2179 [inline] addrconf_dad_begin net/ipv6/addrconf.c:3995 [inline] addrconf_dad_work+0x424/0x16b0 net/ipv6/addrconf.c:4120 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2597 worker_thread+0xa63/0x1210 kernel/workqueue.c:2748 kthread+0x2b8/0x350 kernel/kthread.c:389 Memory state around the buggy address: ffff888023e50100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888023e50180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888023e50200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888023e50280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888023e50300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup