================================================================== BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x631/0xab0 Read of size 48 at addr ffff888049a31ff0 by task syz-executor.0/7691 CPU: 0 PID: 7691 Comm: syz-executor.0 Not tainted 5.15.118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb 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 leaf_shift_left+0xba/0x430 fs/reiserfs/lbalance.c:750 balance_leaf+0x15cd/0x12510 fs/reiserfs/do_balan.c:1409 do_balance+0x309/0x8f0 fs/reiserfs/do_balan.c:1888 reiserfs_insert_item+0xb56/0xcb0 fs/reiserfs/stree.c:2261 reiserfs_get_block+0x20bc/0x5390 fs/reiserfs/inode.c:876 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012 reiserfs_write_begin+0x346/0x810 fs/reiserfs/inode.c:2790 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3903 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3935 call_write_iter include/linux/fs.h:2103 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xacf/0xe50 fs/read_write.c:594 ksys_write+0x1a2/0x2c0 fs/read_write.c:647 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f7308a15389 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f72fef66168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7308b35050 RCX: 00007f7308a15389 RDX: 0000000000000081 RSI: 0000000020000840 RDI: 0000000000000006 RBP: 00007f7308a60493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdc564b08f R14: 00007f72fef66300 R15: 0000000000022000 The buggy address belongs to the page: page:ffffea0001268c40 refcount:2 mapcount:0 mapping:ffff8880198eabf0 index:0x214 pfn:0x49a31 memcg:ffff888061038000 aops:def_blk_aops ino:700000 flags: 0xfff00000002032(referenced|lru|active|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002032 ffffea00021d7148 ffff888085b1f030 ffff8880198eabf0 raw: 0000000000000214 ffff88808718ccb0 00000002ffffffff ffff888061038000 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 7691, ts 772572413023, free_ts 772568481169 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421 __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_insert_item+0xa7a/0xcb0 fs/reiserfs/stree.c:2240 indirect2direct+0x697/0xc00 fs/reiserfs/tail_conversion.c:283 maybe_indirect_to_direct fs/reiserfs/stree.c:1587 [inline] reiserfs_cut_from_item+0xba3/0x2560 fs/reiserfs/stree.c:1694 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+0xd4d/0x1000 fs/attr.c:488 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+0x2a4/0x620 fs/inode.c:587 __dentry_kill+0x436/0x650 fs/dcache.c:582 dentry_kill+0xbb/0x290 dput+0x1f1/0x420 fs/dcache.c:888 __fput+0x5ec/0x890 fs/file_table.c:288 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86 Memory state around the buggy address: ffff888049a31f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888049a31f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888049a32000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888049a32080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888049a32100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================