================================================================== BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x631/0xab0 Read of size 48 at addr ffff8880541edff0 by task syz.1.78/3953 CPU: 1 PID: 3953 Comm: syz.1.78 Not tainted 6.1.111-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 kasan_check_range+0x27f/0x290 mm/kasan/generic.c:189 memcpy+0x25/0x60 mm/kasan/shadow.c:65 leaf_paste_in_buffer+0x631/0xab0 leaf_copy_dir_entries+0x71a/0xc60 fs/reiserfs/lbalance.c:108 leaf_copy_boundary_item+0xbbe/0x21b0 fs/reiserfs/lbalance.c:168 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline] leaf_move_items+0xcd0/0x28a0 fs/reiserfs/lbalance.c:726 leaf_shift_left+0xba/0x430 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+0x228e/0x12510 fs/reiserfs/do_balan.c:1393 do_balance+0x309/0x8f0 fs/reiserfs/do_balan.c:1888 reiserfs_cut_from_item+0x1945/0x2580 fs/reiserfs/stree.c:1838 reiserfs_do_truncate+0xa12/0x15b0 fs/reiserfs/stree.c:1973 reiserfs_truncate_file+0x4d6/0x810 fs/reiserfs/inode.c:2310 reiserfs_setattr+0xc57/0x11c0 fs/reiserfs/inode.c:3395 notify_change+0xce3/0xfc0 fs/attr.c:499 do_truncate+0x21c/0x300 fs/open.c:65 handle_truncate fs/namei.c:3287 [inline] do_open fs/namei.c:3632 [inline] path_openat+0x27e2/0x2e60 fs/namei.c:3785 do_filp_open+0x230/0x480 fs/namei.c:3812 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_openat fs/open.c:1350 [inline] __se_sys_openat fs/open.c:1345 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1345 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8b7137def9 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:00007f8b72259038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8b71535f80 RCX: 00007f8b7137def9 RDX: 000000000000275a RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007f8b713f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8b71535f80 R15: 00007ffd4b051b88 The buggy address belongs to the physical page: page:ffffea0001507b40 refcount:2 mapcount:0 mapping:ffff888140c46af8 index:0x214 pfn:0x541ed memcg:ffff88807532a000 aops:def_blk_aops ino:700001 flags: 0xfff50000002052(referenced|lru|workingset|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff50000002052 ffffea00014fe5c8 ffffea000154c848 ffff888140c46af8 raw: 0000000000000214 ffff8880571ec488 00000002ffffffff ffff88807532a000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 3984, tgid 3952 (syz.1.78), ts 78892818157, free_ts 78890425050 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4290 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5558 folio_alloc+0x1a/0x50 mm/mempolicy.c:2292 filemap_alloc_folio+0xda/0x4f0 mm/filemap.c:971 __filemap_get_folio+0x749/0xe80 mm/filemap.c:1965 pagecache_get_page+0x28/0x250 mm/folio-compat.c:110 find_or_create_page include/linux/pagemap.h:646 [inline] grow_dev_page fs/buffer.c:946 [inline] grow_buffers fs/buffer.c:1011 [inline] __getblk_slow fs/buffer.c:1038 [inline] __getblk_gfp+0x211/0xa20 fs/buffer.c:1333 sb_getblk include/linux/buffer_head.h:356 [inline] get_empty_nodes+0x8c1/0xd70 fs/reiserfs/fix_node.c:890 fix_nodes+0x2615/0x8c70 fs/reiserfs/fix_node.c:2662 reiserfs_paste_into_item+0x65d/0x880 fs/reiserfs/stree.c:2130 reiserfs_get_block+0x2259/0x5150 fs/reiserfs/inode.c:1069 __block_write_begin_int+0x544/0x1a30 fs/buffer.c:1991 reiserfs_write_begin+0x249/0x510 fs/reiserfs/inode.c:2775 generic_cont_expand_simple+0x187/0x2a0 fs/buffer.c:2347 reiserfs_setattr+0x606/0x11c0 fs/reiserfs/inode.c:3305 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3369 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3510 release_pages+0x2836/0x2b40 mm/swap.c:1055 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361 exit_mmap+0x3c3/0x9f0 mm/mmap.c:3239 __mmput+0x115/0x3c0 kernel/fork.c:1199 exit_mm+0x226/0x300 kernel/exit.c:565 do_exit+0x9f6/0x26a0 kernel/exit.c:858 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 get_signal+0x16f7/0x17d0 kernel/signal.c:2870 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 Memory state around the buggy address: ffff8880541edf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880541edf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880541ee000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880541ee080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880541ee100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================