general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] CPU: 1 PID: 7554 Comm: syz.0.1761 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:d_really_is_positive include/linux/dcache.h:493 [inline] RIP: 0010:fuse_atomic_open+0x174/0x3c0 fs/fuse/dir.c:901 Code: 8b 6d c4 44 89 ee 83 e6 40 31 ff e8 36 43 68 ff 44 89 e8 83 e0 40 75 07 e8 09 3f 68 ff eb 26 4d 8d 6e 30 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 3d b2 ac ff 49 83 7d 00 00 74 21 RSP: 0018:ffffc90003447938 EFLAGS: 00010202 RAX: 0000000000000007 RBX: ffff888117554000 RCX: 0000000000000002 RDX: ffff888112313cc0 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90003447990 R08: ffff888112313cc0 R09: 0000000000000002 R10: 00000000fffffffe R11: 0000000000000002 R12: dffffc0000000000 R13: 0000000000000039 R14: 0000000000000009 R15: ffff888133daa640 FS: 00007f39c51ff6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f39c51fef98 CR3: 0000000124670000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: atomic_open fs/namei.c:3344 [inline] lookup_open fs/namei.c:3452 [inline] open_last_lookups fs/namei.c:3549 [inline] path_openat+0xe44/0x2f50 fs/namei.c:3779 do_filp_open+0x1c1/0x3c0 fs/namei.c:3809 do_sys_openat2+0x185/0x7e0 fs/open.c:1341 do_sys_open fs/open.c:1357 [inline] __do_sys_openat fs/open.c:1373 [inline] __se_sys_openat fs/open.c:1368 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1368 x64_sys_call+0x783/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f39c438f6c9 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:00007f39c51ff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f39c45e6360 RCX: 00007f39c438f6c9 RDX: 0000000000000042 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f39c4411f91 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001ff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f39c45e63f8 R14: 00007f39c45e6360 R15: 00007fff0e62bec8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:d_really_is_positive include/linux/dcache.h:493 [inline] RIP: 0010:fuse_atomic_open+0x174/0x3c0 fs/fuse/dir.c:901 Code: 8b 6d c4 44 89 ee 83 e6 40 31 ff e8 36 43 68 ff 44 89 e8 83 e0 40 75 07 e8 09 3f 68 ff eb 26 4d 8d 6e 30 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 3d b2 ac ff 49 83 7d 00 00 74 21 RSP: 0018:ffffc90003447938 EFLAGS: 00010202 RAX: 0000000000000007 RBX: ffff888117554000 RCX: 0000000000000002 RDX: ffff888112313cc0 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90003447990 R08: ffff888112313cc0 R09: 0000000000000002 R10: 00000000fffffffe R11: 0000000000000002 R12: dffffc0000000000 R13: 0000000000000039 R14: 0000000000000009 R15: ffff888133daa640 FS: 00007f39c51ff6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f39c51fef98 CR3: 0000000124670000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 8b 6d c4 mov -0x3c(%rbp),%ebp 3: 44 89 ee mov %r13d,%esi 6: 83 e6 40 and $0x40,%esi 9: 31 ff xor %edi,%edi b: e8 36 43 68 ff call 0xff684346 10: 44 89 e8 mov %r13d,%eax 13: 83 e0 40 and $0x40,%eax 16: 75 07 jne 0x1f 18: e8 09 3f 68 ff call 0xff683f26 1d: eb 26 jmp 0x45 1f: 4d 8d 6e 30 lea 0x30(%r14),%r13 23: 4c 89 e8 mov %r13,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 ef mov %r13,%rdi 34: e8 3d b2 ac ff call 0xffacb276 39: 49 83 7d 00 00 cmpq $0x0,0x0(%r13) 3e: 74 21 je 0x61