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: 469 Comm: syz.0.15 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:d_really_is_positive include/linux/dcache.h:503 [inline] RIP: 0010:fuse_atomic_open+0x2bb/0x2520 fs/fuse/dir.c:875 Code: 44 89 f0 83 e0 40 75 07 e8 62 03 70 ff eb 34 4c 89 64 24 30 4d 8d 7c 24 30 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ff e8 37 2e af ff 49 83 3f 00 74 57 e8 2c RSP: 0018:ffffc90001867340 EFLAGS: 00010203 RAX: 0000000000000008 RBX: fffff5200030ce80 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90001867970 R08: ffff888116bc0000 R09: fffff5200030cddc R10: 00000000fffffffe R11: 0000000000000000 R12: 0000000000000014 R13: 0000000000000014 R14: 0000000000008040 R15: 0000000000000044 FS: 00007fae800086c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae80028ff8 CR3: 000000010de31000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: atomic_open fs/namei.c:3333 [inline] lookup_open fs/namei.c:3441 [inline] open_last_lookups fs/namei.c:3540 [inline] path_openat+0xe31/0x2f20 fs/namei.c:3747 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x15e/0x7f0 fs/open.c:1236 do_sys_open fs/open.c:1252 [inline] __do_sys_openat fs/open.c:1268 [inline] __se_sys_openat fs/open.c:1263 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1263 x64_sys_call+0x219/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 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: 0033:0x7fae805ac6e9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fae80008038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fae80750058 RCX: 00007fae805ac6e9 RDX: 0000000000000040 RSI: 000000002000c380 RDI: ffffffffffffff9c RBP: 00007fae8062a885 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007fae80750058 R15: 00007ffd0b701218 Modules linked in: ---[ end trace 079fea0ee901e99e ]--- RIP: 0010:d_really_is_positive include/linux/dcache.h:503 [inline] RIP: 0010:fuse_atomic_open+0x2bb/0x2520 fs/fuse/dir.c:875 Code: 44 89 f0 83 e0 40 75 07 e8 62 03 70 ff eb 34 4c 89 64 24 30 4d 8d 7c 24 30 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ff e8 37 2e af ff 49 83 3f 00 74 57 e8 2c RSP: 0018:ffffc90001867340 EFLAGS: 00010203 RAX: 0000000000000008 RBX: fffff5200030ce80 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90001867970 R08: ffff888116bc0000 R09: fffff5200030cddc R10: 00000000fffffffe R11: 0000000000000000 R12: 0000000000000014 R13: 0000000000000014 R14: 0000000000008040 R15: 0000000000000044 FS: 00007fae800086c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae80028ff8 CR3: 000000010de31000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 44 89 f0 mov %r14d,%eax 3: 83 e0 40 and $0x40,%eax 6: 75 07 jne 0xf 8: e8 62 03 70 ff call 0xff70036f d: eb 34 jmp 0x43 f: 4c 89 64 24 30 mov %r12,0x30(%rsp) 14: 4d 8d 7c 24 30 lea 0x30(%r12),%r15 19: 4c 89 f8 mov %r15,%rax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 ff mov %r15,%rdi 33: e8 37 2e af ff call 0xffaf2e6f 38: 49 83 3f 00 cmpq $0x0,(%r15) 3c: 74 57 je 0x95 3e: e8 .byte 0xe8 3f: 2c .byte 0x2c