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REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using tea hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
REISERFS warning: reiserfs-5093 is_leaf: item entry count seems wrong *3.5*[2 4106499 0(1) DIR], item_len 35, item_location 3757, free_space(entry_count) 2
REISERFS error (device loop0): vs-5150 search_by_key: invalid format found in block 532. Fsck?
REISERFS (device loop0): Remounting filesystem read-only
general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 1 PID: 5069 Comm: syz-executor877 Not tainted 6.7.0-rc8-syzkaller-00024-gac865f00af29 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:reiserfs_node_data fs/reiserfs/reiserfs.h:2183 [inline]
RIP: 0010:item_head fs/reiserfs/reiserfs.h:2199 [inline]
RIP: 0010:tp_item_head fs/reiserfs/reiserfs.h:2225 [inline]
RIP: 0010:direct2indirect+0x817/0x10f0 fs/reiserfs/tail_conversion.c:119
Code: e5 06 00 00 4c 89 e2 49 63 44 24 08 48 c1 ea 03 80 3c 1a 00 0f 85 d9 06 00 00 4d 8b 24 24 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 1a 00 0f 85 d5 06 00 00 48 8d 54 40 03 49 8b 44 24 28 4c 8d
RSP: 0018:ffffc90003c1f340 EFLAGS: 00010216
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff822a4860
RDX: 0000000000000005 RSI: ffffffff822a486f RDI: 0000000000000028
RBP: ffffc90003c1f4d0 R08: 0000000000000005 R09: 0000000000000001
R10: 00000000fffffffe R11: 0000000000000001 R12: 0000000000000000
R13: ffff888076138ed0 R14: 0000000000000001 R15: ffffc90003c1f740
FS:  0000555555bd1380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005633b1548ff0 CR3: 0000000076b85000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 reiserfs_get_block+0x3a6e/0x4570 fs/reiserfs/inode.c:949
 __block_write_begin_int+0x3c0/0x1560 fs/buffer.c:2119
 reiserfs_write_begin+0x350/0x7d0 fs/reiserfs/inode.c:2767
 generic_perform_write+0x278/0x600 mm/filemap.c:3927
 __generic_file_write_iter+0x1f9/0x240 mm/filemap.c:4022
 generic_file_write_iter+0xe3/0x350 mm/filemap.c:4048
 call_write_iter include/linux/fs.h:2020 [inline]
 do_iter_readv_writev+0x21e/0x3c0 fs/read_write.c:735
 do_iter_write+0x17f/0x7f0 fs/read_write.c:860
 vfs_writev+0x221/0x700 fs/read_write.c:933
 do_writev+0x137/0x370 fs/read_write.c:976
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fa96f55f7b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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:00007ffe8ad7d768 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007ffe8ad7d938 RCX: 00007fa96f55f7b9
RDX: 0000000000000002 RSI: 00000000200013c0 RDI: 0000000000000004
RBP: 00007fa96f5d3610 R08: 00007ffe8ad7d938 R09: 00007ffe8ad7d938
R10: 00007ffe8ad7d938 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe8ad7d928 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:reiserfs_node_data fs/reiserfs/reiserfs.h:2183 [inline]
RIP: 0010:item_head fs/reiserfs/reiserfs.h:2199 [inline]
RIP: 0010:tp_item_head fs/reiserfs/reiserfs.h:2225 [inline]
RIP: 0010:direct2indirect+0x817/0x10f0 fs/reiserfs/tail_conversion.c:119
Code: e5 06 00 00 4c 89 e2 49 63 44 24 08 48 c1 ea 03 80 3c 1a 00 0f 85 d9 06 00 00 4d 8b 24 24 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 1a 00 0f 85 d5 06 00 00 48 8d 54 40 03 49 8b 44 24 28 4c 8d
RSP: 0018:ffffc90003c1f340 EFLAGS: 00010216
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff822a4860
RDX: 0000000000000005 RSI: ffffffff822a486f RDI: 0000000000000028
RBP: ffffc90003c1f4d0 R08: 0000000000000005 R09: 0000000000000001
R10: 00000000fffffffe R11: 0000000000000001 R12: 0000000000000000
R13: ffff888076138ed0 R14: 0000000000000001 R15: ffffc90003c1f740
FS:  0000555555bd1380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000076b85000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	e5 06                	in     $0x6,%eax
   2:	00 00                	add    %al,(%rax)
   4:	4c 89 e2             	mov    %r12,%rdx
   7:	49 63 44 24 08       	movslq 0x8(%r12),%rax
   c:	48 c1 ea 03          	shr    $0x3,%rdx
  10:	80 3c 1a 00          	cmpb   $0x0,(%rdx,%rbx,1)
  14:	0f 85 d9 06 00 00    	jne    0x6f3
  1a:	4d 8b 24 24          	mov    (%r12),%r12
  1e:	49 8d 7c 24 28       	lea    0x28(%r12),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 1a 00          	cmpb   $0x0,(%rdx,%rbx,1) <-- trapping instruction
  2e:	0f 85 d5 06 00 00    	jne    0x709
  34:	48 8d 54 40 03       	lea    0x3(%rax,%rax,2),%rdx
  39:	49 8b 44 24 28       	mov    0x28(%r12),%rax
  3e:	4c                   	rex.WR
  3f:	8d                   	.byte 0x8d