================================================================== BUG: KASAN: use-after-free in leaf_paste_in_buffer+0x66c/0xa14 fs/reiserfs/lbalance.c:-1 Read of size 48 at addr ffff0000f7d1bff0 by task syz.4.122/5040 CPU: 1 PID: 5040 Comm: syz.4.122 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0x100 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x260/0x2a0 mm/kasan/generic.c:189 memcpy+0x48/0x90 mm/kasan/shadow.c:65 leaf_paste_in_buffer+0x66c/0xa14 fs/reiserfs/lbalance.c:-1 leaf_copy_dir_entries+0x45c/0x788 fs/reiserfs/lbalance.c:108 leaf_copy_boundary_item+0x888/0x19dc fs/reiserfs/lbalance.c:-1 leaf_copy_items fs/reiserfs/lbalance.c:551 [inline] leaf_move_items+0x694/0xb9c fs/reiserfs/lbalance.c:726 leaf_shift_left+0xc8/0x3ac 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+0x182c/0xd2f4 fs/reiserfs/do_balan.c:1393 do_balance+0x260/0x774 fs/reiserfs/do_balan.c:1888 reiserfs_delete_item+0x86c/0xc90 fs/reiserfs/stree.c:1371 direct2indirect+0x7b8/0xe88 fs/reiserfs/tail_conversion.c:139 reiserfs_get_block+0x31dc/0x3524 fs/reiserfs/inode.c:949 __block_write_begin_int+0x34c/0x13b8 fs/buffer.c:1991 __block_write_begin+0x7c/0xa0 fs/buffer.c:2041 reiserfs_write_begin+0x328/0x71c fs/reiserfs/inode.c:2775 generic_perform_write+0x230/0x4e4 mm/filemap.c:3862 __generic_file_write_iter+0x130/0x250 mm/filemap.c:3960 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:3989 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5ac/0x7c4 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] __arm64_sys_pwrite64+0x170/0x200 fs/read_write.c:706 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 The buggy address belongs to the physical page: page:000000005959df79 refcount:3 mapcount:0 mapping:0000000075b4c9da index:0x225 pfn:0x137d1b memcg:ffff0000c32b2000 aops:def_blk_aops ino:700004 flags: 0x5ffc40000002042(referenced|workingset|private|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc40000002042 0000000000000000 dead000000000122 ffff0000c058eb10 raw: 0000000000000225 ffff0000e03e9ae0 00000003ffffffff ffff0000c32b2000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f7d1bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000f7d1bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000f7d1c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff0000f7d1c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff0000f7d1c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== REISERFS error (device loop4): vs-4010 is_reusable: block number is out of range 11822 (1024) REISERFS (device loop4): Remounting filesystem read-only REISERFS error (device loop4): vs-4010 is_reusable: block number is out of range 262180 (1024) REISERFS error (device loop4): vs-4010 is_reusable: block number is out of range 589868 (1024) REISERFS error (device loop4): vs-4080 _reiserfs_free_block: block 1: bit already cleared ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5040 at fs/reiserfs/journal.c:3397 journal_end+0x1b0/0x270 fs/reiserfs/journal.c:3397 Modules linked in: CPU: 0 PID: 5040 Comm: syz.4.122 Tainted: G B syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--) pc : journal_end+0x1b0/0x270 fs/reiserfs/journal.c:3397 lr : journal_end+0x1b0/0x270 fs/reiserfs/journal.c:3397 sp : ffff8000219b7680 x29: ffff8000219b7680 x28: 1fffe0001c45f87f x27: 1ffff00004336eea x26: 1ffff00004336ee8 x25: 1fffe0001f6b4930 x24: dfff800000000000 x23: 00000000fffffffb x22: 0000000000000000 x21: ffff8000219b7754 x20: ffff0000fb5a4980 x19: ffff8000219b7740 x18: ffff800011a5bd40 x17: 1fffe00033ee7b7e x16: ffff8000082cb864 x15: 0000000000000002 x14: 0000000000006000 x13: 0000000000ff0100 x12: 0000000000080000 x11: 000000000004e403 x10: ffff80002ba47000 x9 : ffff800008cd3c04 x8 : 000000000004e404 x7 : 0000000000000000 x6 : ffff800008cec3bc x5 : 0000000000000000 x4 : 0000000000000008 x3 : 0000000000000020 x2 : 0000000000000008 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: journal_end+0x1b0/0x270 fs/reiserfs/journal.c:3397 reiserfs_truncate_file+0x5cc/0xaf4 fs/reiserfs/inode.c:2311 reiserfs_truncate_failed_write fs/reiserfs/inode.c:2743 [inline] reiserfs_write_end+0x638/0x7f8 fs/reiserfs/inode.c:2958 generic_perform_write+0x2fc/0x4e4 mm/filemap.c:3873 __generic_file_write_iter+0x130/0x250 mm/filemap.c:3960 generic_file_write_iter+0xb4/0x2b0 mm/filemap.c:3989 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5ac/0x7c4 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] __arm64_sys_pwrite64+0x170/0x200 fs/read_write.c:706 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 irq event stamp: 42919 hardirqs last enabled at (42919): [] raw_spin_rq_unlock_irq kernel/sched/sched.h:1367 [inline] hardirqs last enabled at (42919): [] finish_lock_switch+0xb0/0x1c4 kernel/sched/core.c:5003 hardirqs last disabled at (42918): [] __schedule+0x298/0x1b18 kernel/sched/core.c:6459 softirqs last enabled at (42316): [] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (42314): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]---