syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 UID: 0 PID: 383 Comm: syz.2.17 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__d_entry_type include/linux/dcache.h:415 [inline]
RIP: 0010:d_is_miss include/linux/dcache.h:420 [inline]
RIP: 0010:d_is_negative include/linux/dcache.h:466 [inline]
RIP: 0010:do_renameat2+0x47e/0xc80 fs/namei.c:5118
Code: 74 24 48 44 89 fa e8 81 e3 fe ff 48 3d 01 f0 ff ff 72 0d 49 89 c5 e8 61 e4 9a ff e9 3d 04 00 00 4c 89 e1 49 89 c4 49 c1 ec 03 <41> 0f b6 14 0c 84 d2 48 89 44 24 20 0f 85 f2 05 00 00 8b 18 be 00
RSP: 0018:ffffc900011afd00 EFLAGS: 00010202
RAX: 0000000000000008 RBX: ffff8881150ca200 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8881113cbb20
RBP: ffffc900011afee8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000235f1c R12: 0000000000000001
R13: 0000000000000000 R14: 1ffff92000235f01 R15: 0000000000000000
FS:  00007f58505ff6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f58505fef98 CR3: 0000000113870000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 __do_sys_rename fs/namei.c:5217 [inline]
 __se_sys_rename fs/namei.c:5215 [inline]
 __x64_sys_rename+0x86/0xa0 fs/namei.c:5215
 x64_sys_call+0x150b/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f585078efc9
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:00007f58505ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f58509e6090 RCX: 00007f585078efc9
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000200000000100
RBP: 00007f5850811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f58509e6128 R14: 00007f58509e6090 R15: 00007ffed5748578
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__d_entry_type include/linux/dcache.h:415 [inline]
RIP: 0010:d_is_miss include/linux/dcache.h:420 [inline]
RIP: 0010:d_is_negative include/linux/dcache.h:466 [inline]
RIP: 0010:do_renameat2+0x47e/0xc80 fs/namei.c:5118
Code: 74 24 48 44 89 fa e8 81 e3 fe ff 48 3d 01 f0 ff ff 72 0d 49 89 c5 e8 61 e4 9a ff e9 3d 04 00 00 4c 89 e1 49 89 c4 49 c1 ec 03 <41> 0f b6 14 0c 84 d2 48 89 44 24 20 0f 85 f2 05 00 00 8b 18 be 00
RSP: 0018:ffffc900011afd00 EFLAGS: 00010202
RAX: 0000000000000008 RBX: ffff8881150ca200 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8881113cbb20
RBP: ffffc900011afee8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000235f1c R12: 0000000000000001
R13: 0000000000000000 R14: 1ffff92000235f01 R15: 0000000000000000
FS:  00007f58505ff6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f58505fef98 CR3: 0000000113870000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
   0:	74 24                	je     0x26
   2:	48                   	rex.W
   3:	44 89 fa             	mov    %r15d,%edx
   6:	e8 81 e3 fe ff       	call   0xfffee38c
   b:	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax
  11:	72 0d                	jb     0x20
  13:	49 89 c5             	mov    %rax,%r13
  16:	e8 61 e4 9a ff       	call   0xff9ae47c
  1b:	e9 3d 04 00 00       	jmp    0x45d
  20:	4c 89 e1             	mov    %r12,%rcx
  23:	49 89 c4             	mov    %rax,%r12
  26:	49 c1 ec 03          	shr    $0x3,%r12
* 2a:	41 0f b6 14 0c       	movzbl (%r12,%rcx,1),%edx <-- trapping instruction
  2f:	84 d2                	test   %dl,%dl
  31:	48 89 44 24 20       	mov    %rax,0x20(%rsp)
  36:	0f 85 f2 05 00 00    	jne    0x62e
  3c:	8b 18                	mov    (%rax),%ebx
  3e:	be                   	.byte 0xbe