================================================================== BUG: KASAN: out-of-bounds in leaf_paste_in_buffer+0x1e0/0xbd0 fs/reiserfs/lbalance.c:1017 Read of size 18446744073709493643 at addr ffff888058c67275 by task syz.2.54/6182 CPU: 0 PID: 6182 Comm: syz.2.54 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x288/0x290 mm/kasan/generic.c:187 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 leaf_paste_in_buffer+0x1e0/0xbd0 fs/reiserfs/lbalance.c:1017 leaf_copy_boundary_item+0xc79/0x2180 fs/reiserfs/lbalance.c:199 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline] leaf_move_items+0x8b5/0xe90 fs/reiserfs/lbalance.c:726 leaf_shift_left+0xbd/0x450 fs/reiserfs/lbalance.c:750 balance_leaf_paste_left_whole fs/reiserfs/do_balan.c:560 [inline] balance_leaf_paste_left fs/reiserfs/do_balan.c:594 [inline] balance_leaf_left fs/reiserfs/do_balan.c:613 [inline] balance_leaf+0x2f14/0x10da0 fs/reiserfs/do_balan.c:1409 do_balance+0x2fe/0x940 fs/reiserfs/do_balan.c:1888 reiserfs_paste_into_item+0x6a1/0x7f0 fs/reiserfs/stree.c:2157 reiserfs_get_block+0x1bd3/0x3ed0 fs/reiserfs/inode.c:1069 __block_write_begin_int+0x566/0x1ad0 fs/buffer.c:2124 reiserfs_write_begin+0x20a/0x4c0 fs/reiserfs/inode.c:2771 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4031 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4152 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x195/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe68b18f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe68bf47038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fe68b3e5fa0 RCX: 00007fe68b18f749 RDX: 0000000000000001 RSI: 000020000001f900 RDI: 0000000000000006 RBP: 00007fe68b213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000008000c63 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe68b3e6038 R14: 00007fe68b3e5fa0 R15: 00007ffc5eafe938 The buggy address belongs to the physical page: page:ffffea00016319c0 refcount:1 mapcount:0 mapping:ffff888063c832d8 index:0x116 pfn:0x58c67 memcg:ffff888063ebc000 aops:shmem_aops ino:12 dentry name(?):"memfd:syzkaller" flags: 0xfff6000008023c(referenced|uptodate|dirty|lru|workingset|swapbacked|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff6000008023c ffffea0001656c88 ffffea000164ac48 ffff888063c832d8 raw: 0000000000000116 0000000000000000 00000001ffffffff ffff888063ebc000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 6166, tgid 6165 (syz.1.52), ts 122985082172, free_ts 122780495547 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 __folio_alloc+0x10/0x20 mm/page_alloc.c:4489 vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2242 shmem_alloc_folio+0x179/0x230 mm/shmem.c:1679 shmem_alloc_and_acct_folio+0x189/0x630 mm/shmem.c:1704 shmem_get_folio_gfp+0xcde/0x2ac0 mm/shmem.c:2041 shmem_get_folio mm/shmem.c:2164 [inline] shmem_write_begin+0xf2/0x420 mm/shmem.c:2706 generic_perform_write+0x2fb/0x5b0 mm/filemap.c:4031 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x43b/0x940 fs/read_write.c:584 ksys_write+0x147/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2475 release_pages+0x1fa0/0x2220 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+0x5d0/0x1a40 mm/shmem.c:1026 shmem_truncate_range mm/shmem.c:1135 [inline] shmem_evict_inode+0x273/0xa70 mm/shmem.c:1264 evict+0x486/0x870 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+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 Memory state around the buggy address: ffff888058c67100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888058c67180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888058c67200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff888058c67280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888058c67300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================