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REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names
REISERFS (device loop0): using 3.5.x disk format
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
REISERFS warning: reiserfs-5093 is_leaf: item entry count seems wrong *3.5*[2 1 0(1) DIR], item_len 35, item_location 4029, 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: 3645 Comm: syz-executor195 Not tainted 5.15.113-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:reiserfs_node_data fs/reiserfs/reiserfs.h:2184 [inline]
RIP: 0010:item_head fs/reiserfs/reiserfs.h:2200 [inline]
RIP: 0010:tp_item_head fs/reiserfs/reiserfs.h:2226 [inline]
RIP: 0010:direct2indirect+0x8a7/0x1430 fs/reiserfs/tail_conversion.c:119
Code: d8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 84 c0 0f 85 ea 02 00 00 48 63 1b 49 83 c4 28 4c 89 e0 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 e7 e8 ba 73 b9 ff 4d 8b 34 24 48 8d 1c
RSP: 0018:ffffc900037470a0 EFLAGS: 00010206
RAX: 0000000000000005 RBX: 0000000000000000 RCX: ffff88807bbed940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffc90003747230 R08: ffffffff820fd09d R09: ffffffff820ef579
R10: 0000000000000002 R11: ffff88807bbed940 R12: 0000000000000028
R13: ffffc90003747678 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f8126159700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f81261f10d0 CR3: 000000001cfdd000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 reiserfs_get_block+0x4e84/0x5390 fs/reiserfs/inode.c:957
 __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+0xd4d/0x1000 fs/attr.c:488
 do_truncate+0x21c/0x300 fs/open.c:65
 do_sys_ftruncate+0x2eb/0x390 fs/open.c:193
 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: 0033:0x7f81261ade69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 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:00007f8126159208 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f81262337a8 RCX: 00007f81261ade69
RDX: 00007f81261ade69 RSI: 0000000000000f88 RDI: 0000000000000004
RBP: 00007f81262337a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f81262337ac
R13: 00007ffc06c9f34f R14: 00007f8126159300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 2281bc7642c9781c ]---
RIP: 0010:reiserfs_node_data fs/reiserfs/reiserfs.h:2184 [inline]
RIP: 0010:item_head fs/reiserfs/reiserfs.h:2200 [inline]
RIP: 0010:tp_item_head fs/reiserfs/reiserfs.h:2226 [inline]
RIP: 0010:direct2indirect+0x8a7/0x1430 fs/reiserfs/tail_conversion.c:119
Code: d8 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 84 c0 0f 85 ea 02 00 00 48 63 1b 49 83 c4 28 4c 89 e0 48 c1 e8 03 <42> 80 3c 30 00 74 08 4c 89 e7 e8 ba 73 b9 ff 4d 8b 34 24 48 8d 1c
RSP: 0018:ffffc900037470a0 EFLAGS: 00010206
RAX: 0000000000000005 RBX: 0000000000000000 RCX: ffff88807bbed940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffc90003747230 R08: ffffffff820fd09d R09: ffffffff820ef579
R10: 0000000000000002 R11: ffff88807bbed940 R12: 0000000000000028
R13: ffffc90003747678 R14: dffffc0000000000 R15: 0000000000000010
FS:  00007f8126159700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f811df23000 CR3: 000000001cfdd000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	48 c1 e8 03          	shr    $0x3,%rax
   4:	49 be 00 00 00 00 00 	movabs $0xdffffc0000000000,%r14
   b:	fc ff df
   e:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax
  13:	84 c0                	test   %al,%al
  15:	0f 85 ea 02 00 00    	jne    0x305
  1b:	48 63 1b             	movslq (%rbx),%rbx
  1e:	49 83 c4 28          	add    $0x28,%r12
  22:	4c 89 e0             	mov    %r12,%rax
  25:	48 c1 e8 03          	shr    $0x3,%rax
* 29:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 e7             	mov    %r12,%rdi
  33:	e8 ba 73 b9 ff       	callq  0xffb973f2
  38:	4d 8b 34 24          	mov    (%r12),%r14
  3c:	48                   	rex.W
  3d:	8d                   	.byte 0x8d
  3e:	1c                   	.byte 0x1c