syzbot

general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 0 PID: 291 Comm: syz-executor178 Not tainted 5.15.185-syzkaller-00339-ge678c93d43cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:do_unlinkat+0x27d/0x6b0 fs/namei.c:4340
Code: 44 89 ee e8 65 d2 b6 ff 45 31 e4 41 81 fd 00 00 20 00 41 0f 95 c4 41 83 c4 eb e9 bd 00 00 00 49 8d 7e 30 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 4c 8b 7c 24 18 74 05 e8 52 40 f5 ff 49 8b 46 30 48
RSP: 0018:ffffc900009b7e00 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 1ffff1102433a06c RCX: ffff888104d8e2c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000038
RBP: ffffc900009b7ee8 R08: dffffc0000000000 R09: ffffed102433a072
R10: ffffed102433a072 R11: 1ffff1102433a071 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000008 R15: 0000000000000000
FS:  00007fa02e59b6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa02e59bd58 CR3: 000000011efc4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __do_sys_unlink fs/namei.c:4396 [inline]
 __se_sys_unlink fs/namei.c:4394 [inline]
 __x64_sys_unlink+0x49/0x50 fs/namei.c:4394
 x64_sys_call+0x878/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:88
 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: 0033:0x7fa02e5fa479
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa02e59b218 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fa02e6873f8 RCX: 00007fa02e5fa479
RDX: 00007fa02e5fa479 RSI: 00000000000f4240 RDI: 0000200000000100
RBP: 00007fa02e6873f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa02e654034
R13: 0000200000004300 R14: 0000200000000100 R15: 00007ffe7b8b3ff8
 </TASK>
Modules linked in:
---[ end trace ff6bd4ecdd5d9d35 ]---
RIP: 0010:do_unlinkat+0x27d/0x6b0 fs/namei.c:4340
Code: 44 89 ee e8 65 d2 b6 ff 45 31 e4 41 81 fd 00 00 20 00 41 0f 95 c4 41 83 c4 eb e9 bd 00 00 00 49 8d 7e 30 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 4c 8b 7c 24 18 74 05 e8 52 40 f5 ff 49 8b 46 30 48
RSP: 0018:ffffc900009b7e00 EFLAGS: 00010202
RAX: 0000000000000007 RBX: 1ffff1102433a06c RCX: ffff888104d8e2c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000038
RBP: ffffc900009b7ee8 R08: dffffc0000000000 R09: ffffed102433a072
R10: ffffed102433a072 R11: 1ffff1102433a071 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000008 R15: 0000000000000000
FS:  00007fa02e59b6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa02e59bd58 CR3: 000000011efc4000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	44 89 ee             	mov    %r13d,%esi
   3:	e8 65 d2 b6 ff       	call   0xffb6d26d
   8:	45 31 e4             	xor    %r12d,%r12d
   b:	41 81 fd 00 00 20 00 	cmp    $0x200000,%r13d
  12:	41 0f 95 c4          	setne  %r12b
  16:	41 83 c4 eb          	add    $0xffffffeb,%r12d
  1a:	e9 bd 00 00 00       	jmp    0xdc
  1f:	49 8d 7e 30          	lea    0x30(%r14),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	4c 8b 7c 24 18       	mov    0x18(%rsp),%r15
  34:	74 05                	je     0x3b
  36:	e8 52 40 f5 ff       	call   0xfff5408d
  3b:	49 8b 46 30          	mov    0x30(%r14),%rax
  3f:	48                   	rex.W