syzbot

REISERFS warning (device loop0): vs-13060 reiserfs_update_sd_size: stat data of object [2 5 0x0 SD] (nlink == 1) not found (pos 3)
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 4338 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:reiserfs_get_block+0x161b/0x4100 fs/reiserfs/inode.c:1060
Code: 61 04 00 00 e8 d6 38 80 ff 4d 89 f0 e9 0d 02 00 00 44 8b bc 24 40 03 00 00 4c 89 74 24 38 4d 8d 74 9e fc 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 6f 0d 00 00 4c 89 bc 24 80 00 00 00 45
RSP: 0018:ffffc9000328f340 EFLAGS: 00010203
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff888022111dc0
RDX: 0000000000000000 RSI: 00000000000003f4 RDI: 0000000000000000
RBP: ffffc9000328f8b0 R08: dffffc0000000000 R09: ffffc9000328f800
R10: fffff52000651f04 R11: 1ffff92000651f00 R12: dffffc0000000000
R13: 00000000000003f4 R14: 000000000000000c R15: 0000000000000217
FS:  000055555fff6500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f38108ac000 CR3: 0000000069c06000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __block_write_begin_int+0x54e/0x15a0 fs/buffer.c:2012
 reiserfs_write_begin+0x34b/0x810 fs/reiserfs/inode.c:2790
 generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f848e5cf749
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:00007ffe290a69a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f848e825fa0 RCX: 00007f848e5cf749
RDX: 000000000000045c RSI: 0000200000000440 RDI: 0000000000000006
RBP: 00007f848e653f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f848e825fa0 R14: 00007f848e825fa0 R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace a8dd1a58187a5ba0 ]---
RIP: 0010:reiserfs_get_block+0x161b/0x4100 fs/reiserfs/inode.c:1060
Code: 61 04 00 00 e8 d6 38 80 ff 4d 89 f0 e9 0d 02 00 00 44 8b bc 24 40 03 00 00 4c 89 74 24 38 4d 8d 74 9e fc 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 6f 0d 00 00 4c 89 bc 24 80 00 00 00 45
RSP: 0018:ffffc9000328f340 EFLAGS: 00010203
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff888022111dc0
RDX: 0000000000000000 RSI: 00000000000003f4 RDI: 0000000000000000
RBP: ffffc9000328f8b0 R08: dffffc0000000000 R09: ffffc9000328f800
R10: fffff52000651f04 R11: 1ffff92000651f00 R12: dffffc0000000000
R13: 00000000000003f4 R14: 000000000000000c R15: 0000000000000217
FS:  000055555fff6500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f38108a6000 CR3: 0000000069c06000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	e8 d6 38 80 ff       	call   0xff8038dd
   7:	4d 89 f0             	mov    %r14,%r8
   a:	e9 0d 02 00 00       	jmp    0x21c
   f:	44 8b bc 24 40 03 00 	mov    0x340(%rsp),%r15d
  16:	00
  17:	4c 89 74 24 38       	mov    %r14,0x38(%rsp)
  1c:	4d 8d 74 9e fc       	lea    -0x4(%r14,%rbx,4),%r14
  21:	4c 89 f0             	mov    %r14,%rax
  24:	48 c1 e8 03          	shr    $0x3,%rax
* 28:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2d:	84 c0                	test   %al,%al
  2f:	0f 85 6f 0d 00 00    	jne    0xda4
  35:	4c 89 bc 24 80 00 00 	mov    %r15,0x80(%rsp)
  3c:	00
  3d:	45                   	rex.RB