loop0: detected capacity change from 0 to 64
general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047]
CPU: 1 PID: 5078 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:hfs_find_init+0x66/0x1d0 fs/hfs/bfind.c:21
Code: 7e 18 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 1c 42 8f ff 49 c7 07 00 00 00 00 48 8d 6b 40 49 89 ef 49 c1 ef 03 <43> 0f b6 04 2f 84 c0 0f 85 01 01 00 00 8b 45 00 8d 7c 00 04 be c0
RSP: 0018:ffffc900031af508 EFLAGS: 00010202
RAX: 1ffff92000635ebf RBX: 0000000000000000 RCX: ffff888029723b80
RDX: 0000000000000000 RSI: ffffc900031af5e0 RDI: ffffc900031af5f0
RBP: 0000000000000040 R08: ffffc900031af617 R09: ffffc900031af5e0
R10: dffffc0000000000 R11: fffff52000635ec3 R12: ffff88807a606678
R13: dffffc0000000000 R14: ffffc900031af5e0 R15: 0000000000000008
FS:  00007f444af156c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f444b95ee38 CR3: 000000001fa13000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_get_block+0x553/0xc50 fs/hfs/extent.c:366
 block_read_full_page+0x306/0xd40 fs/buffer.c:2290
 do_read_cache_page+0x8a1/0x1030 mm/filemap.c:-1
 read_mapping_page include/linux/pagemap.h:515 [inline]
 hfs_btree_open+0x4f9/0x1130 fs/hfs/btree.c:78
 hfs_mdb_get+0x137f/0x20d0 fs/hfs/mdb.c:199
 hfs_fill_super+0xf20/0x1590 fs/hfs/super.c:406
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 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: 0033:0x7f444b8b318a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f444af14e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f444af14ee0 RCX: 00007f444b8b318a
RDX: 0000200000000180 RSI: 00002000000000c0 RDI: 00007f444af14ea0
RBP: 0000200000000180 R08: 00007f444af14ee0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007f444af14ea0 R14: 00000000000002b8 R15: 0000200000000880
 </TASK>
Modules linked in:
---[ end trace 46f025bf87742cc0 ]---
RIP: 0010:hfs_find_init+0x66/0x1d0 fs/hfs/bfind.c:21
Code: 7e 18 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 1c 42 8f ff 49 c7 07 00 00 00 00 48 8d 6b 40 49 89 ef 49 c1 ef 03 <43> 0f b6 04 2f 84 c0 0f 85 01 01 00 00 8b 45 00 8d 7c 00 04 be c0
RSP: 0018:ffffc900031af508 EFLAGS: 00010202
RAX: 1ffff92000635ebf RBX: 0000000000000000 RCX: ffff888029723b80
RDX: 0000000000000000 RSI: ffffc900031af5e0 RDI: ffffc900031af5f0
RBP: 0000000000000040 R08: ffffc900031af617 R09: ffffc900031af5e0
R10: dffffc0000000000 R11: fffff52000635ec3 R12: ffff88807a606678
R13: dffffc0000000000 R14: ffffc900031af5e0 R15: 0000000000000008
FS:  00007f444af156c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f444b95ee38 CR3: 000000001fa13000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	7e 18                	jle    0x1a
   2:	4c 89 f8             	mov    %r15,%rax
   5:	48 c1 e8 03          	shr    $0x3,%rax
   9:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   e:	74 08                	je     0x18
  10:	4c 89 ff             	mov    %r15,%rdi
  13:	e8 1c 42 8f ff       	call   0xff8f4234
  18:	49 c7 07 00 00 00 00 	movq   $0x0,(%r15)
  1f:	48 8d 6b 40          	lea    0x40(%rbx),%rbp
  23:	49 89 ef             	mov    %rbp,%r15
  26:	49 c1 ef 03          	shr    $0x3,%r15
* 2a:	43 0f b6 04 2f       	movzbl (%r15,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 01 01 00 00    	jne    0x138
  37:	8b 45 00             	mov    0x0(%rbp),%eax
  3a:	8d 7c 00 04          	lea    0x4(%rax,%rax,1),%edi
  3e:	be                   	.byte 0xbe
  3f:	c0                   	.byte 0xc0