================================================================== BUG: KASAN: use-after-free in data_blkaddr fs/f2fs/f2fs.h:2782 [inline] BUG: KASAN: use-after-free in is_alive fs/f2fs/gc.c:1029 [inline] BUG: KASAN: use-after-free in gc_data_segment+0x29fd/0x3040 fs/f2fs/gc.c:1448 Read of size 4 at addr ffff8881569ec874 by task kworker/u4:2/104 CPU: 0 PID: 104 Comm: kworker/u4:2 Not tainted 5.10.149-syzkaller-01404-g69a9a62c66bb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3c0 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report+0x1a4/0x1f0 mm/kasan/report.c:436 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 data_blkaddr fs/f2fs/f2fs.h:2782 [inline] is_alive fs/f2fs/gc.c:1029 [inline] gc_data_segment+0x29fd/0x3040 fs/f2fs/gc.c:1448 do_garbage_collect+0xd3a/0x1de0 fs/f2fs/gc.c:1652 f2fs_gc+0x89e/0x19c0 fs/f2fs/gc.c:1745 f2fs_balance_fs+0x339/0x3e0 fs/f2fs/segment.c:528 __write_node_page+0xd99/0x1980 fs/f2fs/node.c:1652 f2fs_sync_node_pages+0x104c/0x1600 fs/f2fs/node.c:1999 f2fs_write_node_pages+0x302/0x870 fs/f2fs/node.c:2109 do_writepages+0x13a/0x280 mm/page-writeback.c:2358 __writeback_single_inode+0xb8/0x6e0 fs/fs-writeback.c:1467 writeback_sb_inodes+0x999/0x1700 fs/fs-writeback.c:1730 wb_writeback+0x42f/0xc20 fs/fs-writeback.c:1905 wb_do_writeback+0x222/0xbd0 fs/fs-writeback.c:2050 wb_workfn+0xf8/0x3f0 fs/fs-writeback.c:2091 process_one_work+0x726/0xc10 kernel/workqueue.c:2296 worker_thread+0xb27/0x1550 kernel/workqueue.c:2442 kthread+0x349/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:299 Allocated by task 161: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:428 [inline] ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516 kasan_kmalloc include/linux/kasan.h:269 [inline] kmem_cache_alloc_trace+0x1dd/0x330 mm/slub.c:2983 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] kernfs_iop_get_link+0x65/0x590 fs/kernfs/symlink.c:135 vfs_readlink+0x177/0x420 fs/namei.c:4631 do_readlinkat+0x28f/0x3b0 fs/stat.c:426 __do_sys_readlink fs/stat.c:447 [inline] __se_sys_readlink fs/stat.c:444 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:444 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xc6 Freed by task 161: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:360 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1604 [inline] slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630 slab_free mm/slub.c:3212 [inline] kfree+0xc3/0x290 mm/slub.c:4200 kfree_link+0x15/0x20 fs/libfs.c:1204 do_delayed_call include/linux/delayed_call.h:28 [inline] vfs_readlink+0x25f/0x420 fs/namei.c:4636 do_readlinkat+0x28f/0x3b0 fs/stat.c:426 __do_sys_readlink fs/stat.c:447 [inline] __se_sys_readlink fs/stat.c:444 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:444 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xc6 The buggy address belongs to the object at ffff8881569ec000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2164 bytes inside of 4096-byte region [ffff8881569ec000, ffff8881569ed000) The buggy address belongs to the page: page:ffffea00055a7a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1569e8 head:ffffea00055a7a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 0000000000000000 0000000200000001 ffff888100042c00 raw: 0000000000000000 0000000000040004 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 666, ts 190940866312, free_ts 182712403713 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2386 [inline] prep_new_page mm/page_alloc.c:2392 [inline] get_page_from_freelist+0x755/0x810 mm/page_alloc.c:4073 __alloc_pages_nodemask+0x3b6/0x890 mm/page_alloc.c:5160 alloc_slab_page mm/slub.c:1815 [inline] allocate_slab+0x78/0x540 mm/slub.c:1817 new_slab mm/slub.c:1878 [inline] new_slab_objects mm/slub.c:2636 [inline] ___slab_alloc+0x131/0x2e0 mm/slub.c:2800 __slab_alloc+0x63/0xa0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] kmem_cache_alloc_trace+0x20e/0x330 mm/slub.c:2981 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:664 [inline] uevent_show+0x166/0x330 drivers/base/core.c:2277 dev_attr_show+0x56/0xd0 drivers/base/core.c:1984 sysfs_kf_seq_show+0x26b/0x400 fs/sysfs/file.c:61 kernfs_seq_show+0x117/0x160 fs/kernfs/file.c:168 seq_read_iter+0x429/0xd20 fs/seq_file.c:230 kernfs_fop_read_iter+0x161/0x490 fs/kernfs/file.c:241 call_read_iter include/linux/fs.h:1941 [inline] new_sync_read fs/read_write.c:415 [inline] vfs_read+0x9e2/0xbf0 fs/read_write.c:496 ksys_read+0x198/0x2c0 fs/read_write.c:634 __do_sys_read fs/read_write.c:644 [inline] __se_sys_read fs/read_write.c:642 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:642 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1332 [inline] free_pcp_prepare+0x18c/0x1c0 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3293 [inline] free_unref_page_list+0x11d/0x660 mm/page_alloc.c:3367 release_pages+0xc24/0xc60 mm/swap.c:1082 __pagevec_release+0x81/0xf0 mm/swap.c:1102 pagevec_release include/linux/pagevec.h:88 [inline] truncate_inode_pages_range+0x9f8/0x1940 mm/truncate.c:367 truncate_inode_pages mm/truncate.c:473 [inline] truncate_inode_pages_final+0xc1/0xd0 mm/truncate.c:524 f2fs_evict_inode+0x181/0x1350 fs/f2fs/inode.c:738 evict+0x2a3/0x6c0 fs/inode.c:577 dispose_list fs/inode.c:612 [inline] evict_inodes+0x628/0x6b0 fs/inode.c:662 generic_shutdown_super+0x97/0x2c0 fs/super.c:454 kill_block_super+0x80/0xe0 fs/super.c:1446 kill_f2fs_super+0x2f3/0x3c0 fs/f2fs/super.c:4348 deactivate_locked_super+0xb0/0x100 fs/super.c:335 deactivate_super+0xa5/0xd0 fs/super.c:366 cleanup_mnt+0x45f/0x510 fs/namespace.c:1118 __cleanup_mnt+0x19/0x20 fs/namespace.c:1125 Memory state around the buggy address: ffff8881569ec700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881569ec780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881569ec800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881569ec880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881569ec900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================