================================================================== BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x631/0xab0 Read of size 48 at addr ffff88806bf0bff0 by task syz.4.197/5097 CPU: 1 PID: 5097 Comm: syz.4.197 Not tainted 5.15.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 kasan_check_range+0x27e/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 balance_leaf_when_delete_left fs/reiserfs/do_balan.c:167 [inline] balance_leaf_when_delete fs/reiserfs/do_balan.c:272 [inline] balance_leaf+0xd479/0x12510 fs/reiserfs/do_balan.c:1393 do_balance+0x309/0x8f0 fs/reiserfs/do_balan.c:1888 reiserfs_cut_from_item+0x1945/0x2560 fs/reiserfs/stree.c:1838 reiserfs_do_truncate+0xa12/0x15b0 fs/reiserfs/stree.c:1973 reiserfs_truncate_file+0x638/0xda0 fs/reiserfs/inode.c:2318 reiserfs_setattr+0xa4d/0xf90 fs/reiserfs/inode.c:3409 notify_change+0xc6d/0xf50 fs/attr.c:505 do_truncate+0x21c/0x300 fs/open.c:65 handle_truncate fs/namei.c:3265 [inline] do_open fs/namei.c:3612 [inline] path_openat+0x28a3/0x2f20 fs/namei.c:3742 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff8b99a0d29 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:00007ff8b7811038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ff8b9b90fa0 RCX: 00007ff8b99a0d29 RDX: 000000000000275a RSI: 0000000020000040 RDI: ffffffffffffff9c RBP: 00007ff8b9a1cb08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff8b9b90fa0 R15: 00007ffe2094ce68 The buggy address belongs to the page: page:ffffea0001afc2c0 refcount:2 mapcount:0 mapping:ffff888140895af0 index:0x219 pfn:0x6bf0b memcg:ffff8880199b0000 aops:def_blk_aops ino:700004 flags: 0xfff00000002032(referenced|lru|active|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002032 ffffea0001afc288 ffffea00017e71c8 ffff888140895af0 raw: 0000000000000219 ffff888060b1c0e8 00000002ffffffff ffff8880199b0000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 5097, ts 124743388744, free_ts 124471604300 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465 __page_cache_alloc+0xd4/0x4a0 mm/filemap.c:1022 pagecache_get_page+0xa91/0x1010 mm/filemap.c:1940 find_or_create_page include/linux/pagemap.h:420 [inline] grow_dev_page fs/buffer.c:949 [inline] grow_buffers fs/buffer.c:1014 [inline] __getblk_slow fs/buffer.c:1041 [inline] __getblk_gfp+0x22a/0xaf0 fs/buffer.c:1336 sb_getblk include/linux/buffer_head.h:361 [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+0x226a/0x5390 fs/reiserfs/inode.c:1077 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012 reiserfs_write_begin+0x346/0x810 fs/reiserfs/inode.c:2790 generic_cont_expand_simple+0x144/0x230 fs/buffer.c:2362 reiserfs_setattr+0x3ff/0xf90 fs/reiserfs/inode.c:3319 notify_change+0xc6d/0xf50 fs/attr.c:505 do_truncate+0x21c/0x300 fs/open.c:65 do_sys_ftruncate+0x2eb/0x390 fs/open.c:193 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page_list+0x1f7/0x8e0 mm/page_alloc.c:3433 release_pages+0x1bb9/0x1f40 mm/swap.c:963 __pagevec_release+0x80/0xf0 mm/swap.c:983 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x67a/0x1b50 mm/shmem.c:964 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145 evict+0x529/0x930 fs/inode.c:622 __dentry_kill+0x436/0x650 fs/dcache.c:586 dentry_kill+0xbb/0x290 dput+0xd8/0x1a0 fs/dcache.c:893 __fput+0x636/0x8e0 fs/file_table.c:288 task_work_run+0x129/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x6a3/0x2480 kernel/exit.c:874 do_group_exit+0x144/0x310 kernel/exit.c:996 get_signal+0xc66/0x14e0 kernel/signal.c:2900 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 Memory state around the buggy address: ffff88806bf0bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806bf0bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806bf0c000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88806bf0c080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806bf0c100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================