================================================================== BUG: KASAN: use-after-free in inode_dirtied_after fs/fs-writeback.c:1335 [inline] BUG: KASAN: use-after-free in move_expired_inodes+0x186/0x8e0 fs/fs-writeback.c:1367 Read of size 8 at addr ffff888075182898 by task kworker/u4:5/20008 CPU: 0 PID: 20008 Comm: kworker/u4:5 Not tainted 6.0.0-syzkaller-09423-g493ffd6605b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 print_address_description+0x65/0x4b0 mm/kasan/report.c:317 print_report+0x108/0x1f0 mm/kasan/report.c:433 kasan_report+0xc3/0xf0 mm/kasan/report.c:495 inode_dirtied_after fs/fs-writeback.c:1335 [inline] move_expired_inodes+0x186/0x8e0 fs/fs-writeback.c:1367 queue_io+0x250/0x400 fs/fs-writeback.c:1427 wb_writeback+0x3d3/0x7b0 fs/fs-writeback.c:2042 wb_do_writeback fs/fs-writeback.c:2187 [inline] wb_workfn+0x3cb/0xef0 fs/fs-writeback.c:2227 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 22444: 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:437 [inline] __kasan_slab_alloc+0xa3/0xd0 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3248 [inline] slab_alloc mm/slub.c:3256 [inline] __kmem_cache_alloc_lru mm/slub.c:3263 [inline] kmem_cache_alloc_lru+0x175/0x2d0 mm/slub.c:3280 alloc_inode_sb include/linux/fs.h:3107 [inline] fat_alloc_inode+0x25/0xc0 fs/fat/inode.c:750 alloc_inode fs/inode.c:259 [inline] new_inode_pseudo+0x61/0x1d0 fs/inode.c:1018 new_inode+0x25/0x1d0 fs/inode.c:1046 fat_build_inode+0x1e8/0x3e0 fs/fat/inode.c:603 vfat_create+0x240/0x3a0 fs/fat/namei_vfat.c:776 lookup_open fs/namei.c:3413 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x12d0/0x2df0 fs/namei.c:3688 do_filp_open+0x264/0x4f0 fs/namei.c:3718 do_sys_openat2+0x124/0x4e0 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+0x243/0x290 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 22447: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x3d/0x60 mm/kasan/common.c:45 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:367 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kmem_cache_free+0x95/0x1d0 mm/slub.c:3556 rcu_do_batch kernel/rcu/tree.c:2248 [inline] rcu_core+0x981/0x1610 kernel/rcu/tree.c:2508 __do_softirq+0x277/0x738 kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x2b/0x50 mm/kasan/common.c:38 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:348 call_rcu+0x163/0x970 kernel/rcu/tree.c:2796 __dentry_kill+0x3b1/0x5b0 fs/dcache.c:607 dentry_kill+0xbb/0x290 dput+0x1f3/0x410 fs/dcache.c:913 __fput+0x5e4/0x880 fs/file_table.c:328 task_work_run+0x146/0x1c0 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x124/0x150 kernel/entry/common.c:169 exit_to_user_mode_prepare+0xb2/0x140 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:294 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x2b/0x50 mm/kasan/common.c:38 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:348 call_rcu+0x163/0x970 kernel/rcu/tree.c:2796 fat_put_super+0x90/0xb0 fs/fat/inode.c:740 generic_shutdown_super+0x130/0x310 fs/super.c:491 kill_block_super+0x79/0xd0 fs/super.c:1427 deactivate_locked_super+0xa7/0xf0 fs/super.c:331 cleanup_mnt+0x4ce/0x560 fs/namespace.c:1186 task_work_run+0x146/0x1c0 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x124/0x150 kernel/entry/common.c:169 exit_to_user_mode_prepare+0xb2/0x140 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:294 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880751825e0 which belongs to the cache fat_inode_cache of size 1488 The buggy address is located 696 bytes inside of 1488-byte region [ffff8880751825e0, ffff888075182bb0) The buggy address belongs to the physical page: page:ffffea0001d46000 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880751838d0 pfn:0x75180 head:ffffea0001d46000 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88804d4c4b01 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff8881466e1a00 raw: ffff8880751838d0 0000000080140012 00000001ffffffff ffff88804d4c4b01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 12813, tgid 12812 (syz-executor.5), ts 1442823715619, free_ts 1439467377496 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x742/0x7c0 mm/page_alloc.c:4283 __alloc_pages+0x259/0x560 mm/page_alloc.c:5549 alloc_slab_page+0x70/0xf0 mm/slub.c:1829 allocate_slab+0x5e/0x520 mm/slub.c:1974 new_slab mm/slub.c:2034 [inline] ___slab_alloc+0x3ee/0xc40 mm/slub.c:3036 __slab_alloc mm/slub.c:3123 [inline] slab_alloc_node mm/slub.c:3214 [inline] slab_alloc mm/slub.c:3256 [inline] __kmem_cache_alloc_lru mm/slub.c:3263 [inline] kmem_cache_alloc_lru+0x225/0x2d0 mm/slub.c:3280 alloc_inode_sb include/linux/fs.h:3107 [inline] fat_alloc_inode+0x25/0xc0 fs/fat/inode.c:750 alloc_inode fs/inode.c:259 [inline] new_inode_pseudo+0x61/0x1d0 fs/inode.c:1018 new_inode+0x25/0x1d0 fs/inode.c:1046 fat_build_inode+0x1e8/0x3e0 fs/fat/inode.c:603 vfat_create+0x240/0x3a0 fs/fat/namei_vfat.c:776 lookup_open fs/namei.c:3413 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x12d0/0x2df0 fs/namei.c:3688 do_filp_open+0x264/0x4f0 fs/namei.c:3718 do_sys_openat2+0x124/0x4e0 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+0x243/0x290 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x812/0x900 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x7d/0x5f0 mm/page_alloc.c:3476 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:447 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3248 [inline] slab_alloc mm/slub.c:3256 [inline] __kmalloc+0x1bd/0x370 mm/slub.c:4425 kmalloc include/linux/slab.h:605 [inline] kernfs_fop_write_iter+0x164/0x500 fs/kernfs/file.c:307 call_write_iter include/linux/fs.h:2190 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7dc/0xc50 fs/read_write.c:584 ksys_write+0x177/0x2a0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888075182780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888075182800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888075182880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888075182900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888075182980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================