loop6: rw=524288, sector=165, nr_sectors = 1 limit=64
syz.6.24: attempt to access beyond end of device
loop6: rw=524288, sector=166, nr_sectors = 1 limit=64
syz.6.24: attempt to access beyond end of device
loop6: rw=524288, sector=167, nr_sectors = 1 limit=64
syz.6.24: attempt to access beyond end of device
loop6: rw=0, sector=161, nr_sectors = 1 limit=64
BUG: kernel NULL pointer dereference, address: 0000000000000028
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 10472f067 P4D 10472f067 PUD 10979f067 PMD 0 
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 UID: 0 PID: 4765 Comm: syz.6.24 Not tainted 6.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
RIP: 0010:exfat_get_dentry_cached fs/exfat/dir.c:727 [inline]
RIP: 0010:exfat_init_ext_entry+0xcd/0x120 fs/exfat/dir.c:498
Code: 41 8b 41 08 0f b6 4e 14 44 01 d0 48 8b 7e 18 89 c2 48 98 d3 fa 49 8b 49 28 48 63 d2 48 83 ef 01 48 21 c7 4c 89 c0 48 8b 14 d1 <48> 03 7a 28 66 89 1f 48 8d 57 02 48 83 c7 20 0f b7 08 48 8d 70 02
RSP: 0018:ffffc90004203890 EFLAGS: 00010246
RAX: ffffc90004203ab4 RBX: 00000000000000c1 RCX: ffffc900042038e8
RDX: 0000000000000000 RSI: ffff88810c6a4000 RDI: 0000000000000000
RBP: ffffc90004203b48 R08: ffffc90004203ab4 R09: ffffc900042038d8
R10: 0000000000000200 R11: ffffc90004203b0e R12: ffffc90004203b60
R13: 0000000000000000 R14: ffffc900042038d8 R15: 000000000000011f
FS:  00007fa42833a6c0(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000028 CR3: 0000000106fba000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 exfat_add_entry+0x155/0x2c0 fs/exfat/namei.c:517
 exfat_create+0x87/0x1a0 fs/exfat/namei.c:565
 lookup_open.isra.0+0x606/0x6a0 fs/namei.c:3649
 open_last_lookups fs/namei.c:3748 [inline]
 path_openat+0x52a/0xc60 fs/namei.c:3984
 do_filp_open+0xd3/0x180 fs/namei.c:4014
 do_sys_openat2+0xa6/0xe0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_creat fs/open.c:1495 [inline]
 __se_sys_creat fs/open.c:1489 [inline]
 __x64_sys_creat+0x48/0x70 fs/open.c:1489
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x6d/0x170 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa42757ff19
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:00007fa42833a058 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fa427746080 RCX: 00007fa42757ff19
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000e00
RBP: 00007fa4275f3cc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa427746080 R15: 00007ffec935c078
 </TASK>
Modules linked in:
CR2: 0000000000000028
---[ end trace 0000000000000000 ]---
RIP: 0010:exfat_get_dentry_cached fs/exfat/dir.c:727 [inline]
RIP: 0010:exfat_init_ext_entry+0xcd/0x120 fs/exfat/dir.c:498
Code: 41 8b 41 08 0f b6 4e 14 44 01 d0 48 8b 7e 18 89 c2 48 98 d3 fa 49 8b 49 28 48 63 d2 48 83 ef 01 48 21 c7 4c 89 c0 48 8b 14 d1 <48> 03 7a 28 66 89 1f 48 8d 57 02 48 83 c7 20 0f b7 08 48 8d 70 02
RSP: 0018:ffffc90004203890 EFLAGS: 00010246
RAX: ffffc90004203ab4 RBX: 00000000000000c1 RCX: ffffc900042038e8
RDX: 0000000000000000 RSI: ffff88810c6a4000 RDI: 0000000000000000
RBP: ffffc90004203b48 R08: ffffc90004203ab4 R09: ffffc900042038d8
R10: 0000000000000200 R11: ffffc90004203b0e R12: ffffc90004203b60
R13: 0000000000000000 R14: ffffc900042038d8 R15: 000000000000011f
FS:  00007fa42833a6c0(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000028 CR3: 0000000106fba000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	41 8b 41 08          	mov    0x8(%r9),%eax
   4:	0f b6 4e 14          	movzbl 0x14(%rsi),%ecx
   8:	44 01 d0             	add    %r10d,%eax
   b:	48 8b 7e 18          	mov    0x18(%rsi),%rdi
   f:	89 c2                	mov    %eax,%edx
  11:	48 98                	cltq
  13:	d3 fa                	sar    %cl,%edx
  15:	49 8b 49 28          	mov    0x28(%r9),%rcx
  19:	48 63 d2             	movslq %edx,%rdx
  1c:	48 83 ef 01          	sub    $0x1,%rdi
  20:	48 21 c7             	and    %rax,%rdi
  23:	4c 89 c0             	mov    %r8,%rax
  26:	48 8b 14 d1          	mov    (%rcx,%rdx,8),%rdx
* 2a:	48 03 7a 28          	add    0x28(%rdx),%rdi <-- trapping instruction
  2e:	66 89 1f             	mov    %bx,(%rdi)
  31:	48 8d 57 02          	lea    0x2(%rdi),%rdx
  35:	48 83 c7 20          	add    $0x20,%rdi
  39:	0f b7 08             	movzwl (%rax),%ecx
  3c:	48 8d 70 02          	lea    0x2(%rax),%rsi