REISERFS (device loop9): Using tea hash to sort names REISERFS (device loop9): Created .reiserfs_priv - reserved for xattr storage. ================================================================== BUG: KASAN: use-after-free in leaf_paste_entries+0x49e/0x10e0 fs/reiserfs/lbalance.c:1362 Read of size 2 at addr ffff888052c9000c by task syz.9.1672/14335 CPU: 1 PID: 14335 Comm: syz.9.1672 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 leaf_paste_entries+0x49e/0x10e0 fs/reiserfs/lbalance.c:1362 leaf_copy_dir_entries+0x6ee/0x9e0 fs/reiserfs/lbalance.c:119 leaf_copy_boundary_item+0xb8c/0x21b0 fs/reiserfs/lbalance.c:168 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline] leaf_move_items+0x8cf/0xec0 fs/reiserfs/lbalance.c:726 leaf_shift_left+0xbd/0x450 fs/reiserfs/lbalance.c:750 balance_leaf_when_delete_left fs/reiserfs/do_balan.c:194 [inline] balance_leaf_when_delete fs/reiserfs/do_balan.c:272 [inline] balance_leaf+0x132e/0x10df0 fs/reiserfs/do_balan.c:1393 do_balance+0x31c/0x930 fs/reiserfs/do_balan.c:1888 reiserfs_cut_from_item+0x156e/0x1fe0 fs/reiserfs/stree.c:1836 reiserfs_do_truncate+0x9c2/0x12d0 fs/reiserfs/stree.c:1971 reiserfs_truncate_file+0x480/0x7d0 fs/reiserfs/inode.c:2306 reiserfs_setattr+0xc1e/0x1230 fs/reiserfs/inode.c:3392 notify_change+0xb0d/0xe10 fs/attr.c:499 do_truncate+0x1b0/0x240 fs/open.c:66 handle_truncate fs/namei.c:3299 [inline] do_open fs/namei.c:3644 [inline] path_openat+0x2a32/0x3230 fs/namei.c:3797 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_open fs/open.c:1444 [inline] __se_sys_open fs/open.c:1440 [inline] __x64_sys_open+0x11f/0x140 fs/open.c:1440 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4c9e79cdd9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4c9f6a1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f4c9ea15fa0 RCX: 00007f4c9e79cdd9 RDX: 0000000000000000 RSI: 000000000014937e RDI: 00002000000002c0 RBP: 00007f4c9e832d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4c9ea16038 R14: 00007f4c9ea15fa0 R15: 00007fff48ecc4f8 The buggy address belongs to the physical page: page:ffffea00014b2400 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x52c90 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffff7f(buddy) raw: 00fff00000000000 ffffea00015c7008 ffffea0001478808 0000000000000000 raw: 0000000000000001 0000000000000004 00000000ffffff7f 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 14338, tgid 14337 (syz.7.1661), ts 939312406835, free_ts 940121703688 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 __folio_alloc+0x10/0x20 mm/page_alloc.c:4532 vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2240 shmem_alloc_folio+0x1a9/0x2a0 mm/shmem.c:1679 shmem_alloc_and_acct_folio+0x1e6/0x6d0 mm/shmem.c:1704 shmem_get_folio_gfp+0xcde/0x2aa0 mm/shmem.c:2041 shmem_fault+0x1b8/0x810 mm/shmem.c:2248 __do_fault+0x13b/0x4d0 mm/memory.c:4244 do_read_fault mm/memory.c:4638 [inline] do_fault mm/memory.c:4775 [inline] do_pte_missing mm/memory.c:3689 [inline] handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x2299/0x4c00 mm/memory.c:5353 faultin_page mm/gup.c:868 [inline] __get_user_pages+0x5d0/0x1380 mm/gup.c:1167 populate_vma_page_range+0x2c1/0x380 mm/gup.c:1593 __mm_populate+0x260/0x390 mm/gup.c:1696 mm_populate include/linux/mm.h:3383 [inline] vm_mmap_pgoff+0x2da/0x3f0 mm/util.c:561 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2504 release_pages+0x1f7a/0x2200 mm/swap.c:1022 __folio_batch_release+0x71/0xe0 mm/swap.c:1042 folio_batch_release include/linux/pagevec.h:83 [inline] shmem_undo_range+0x630/0x1b20 mm/shmem.c:1026 shmem_truncate_range mm/shmem.c:1135 [inline] shmem_evict_inode+0x245/0x9e0 mm/shmem.c:1264 evict+0x4ca/0x8d0 fs/inode.c:705 __dentry_kill+0x431/0x650 fs/dcache.c:611 dentry_kill+0xb8/0x290 fs/dcache.c:-1 dput+0xfe/0x1e0 fs/dcache.c:918 __fput+0x5e5/0x970 fs/file_table.c:392 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x95a/0x2460 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 Memory state around the buggy address: ffff888052c8ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888052c8ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888052c90000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888052c90080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888052c90100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 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