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: 19215 Comm: syz-executor.4 Not tainted 5.10.187-syzkaller-00057-g8a427269c016 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 RIP: 0010:d_really_is_positive include/linux/dcache.h:499 [inline] RIP: 0010:fuse_atomic_open+0x27c/0x31a0 fs/fuse/dir.c:846 Code: e0 40 4c 8b 64 24 28 75 07 e8 c0 4f 6d ff eb 37 48 8b 44 24 60 48 8d 58 30 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 66 7e aa ff 48 83 3b 00 0f 84 a6 00 RSP: 0018:ffffc900012072e0 EFLAGS: 00010202 RAX: 0000000000000007 RBX: 0000000000000038 RCX: dffffc0000000000 RDX: ffff88810f984f00 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90001207910 R08: ffffffff81fd3dcf R09: ffffed102bdd5cec R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88815eeae428 R13: ffff888118df9000 R14: 1ffff92000240e74 R15: 0000000000000008 FS: 00007f9b40add6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020006000 CR3: 0000000158e62000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: atomic_open fs/namei.c:3120 [inline] lookup_open fs/namei.c:3225 [inline] open_last_lookups fs/namei.c:3323 [inline] path_openat+0xff0/0x3000 fs/namei.c:3512 do_filp_open+0x21c/0x460 fs/namei.c:3542 do_sys_openat2+0x13f/0x6f0 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_openat fs/open.c:1249 [inline] __se_sys_openat fs/open.c:1244 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1244 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xc6 RIP: 0033:0x7f9b41d7bae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f9b40add0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f9b41e9b050 RCX: 00007f9b41d7bae9 RDX: 00000000000204c0 RSI: 0000000020004b00 RDI: 0000000000000004 RBP: 00007f9b41dc747a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000109 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f9b41e9b050 R15: 00007ffe43471b48 Modules linked in: ---[ end trace cca5d7dfeed8b199 ]--- RIP: 0010:d_really_is_positive include/linux/dcache.h:499 [inline] RIP: 0010:fuse_atomic_open+0x27c/0x31a0 fs/fuse/dir.c:846 Code: e0 40 4c 8b 64 24 28 75 07 e8 c0 4f 6d ff eb 37 48 8b 44 24 60 48 8d 58 30 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 66 7e aa ff 48 83 3b 00 0f 84 a6 00 RSP: 0018:ffffc900012072e0 EFLAGS: 00010202 RAX: 0000000000000007 RBX: 0000000000000038 RCX: dffffc0000000000 RDX: ffff88810f984f00 RSI: 0000000000000040 RDI: 0000000000000000 RBP: ffffc90001207910 R08: ffffffff81fd3dcf R09: ffffed102bdd5cec R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88815eeae428 R13: ffff888118df9000 R14: 1ffff92000240e74 R15: 0000000000000008 FS: 00007f9b40add6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000158e62000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: e0 40 loopne 0x42 2: 4c 8b 64 24 28 mov 0x28(%rsp),%r12 7: 75 07 jne 0x10 9: e8 c0 4f 6d ff call 0xff6d4fce e: eb 37 jmp 0x47 10: 48 8b 44 24 60 mov 0x60(%rsp),%rax 15: 48 8d 58 30 lea 0x30(%rax),%rbx 19: 48 89 d8 mov %rbx,%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: 48 89 df mov %rbx,%rdi 33: e8 66 7e aa ff call 0xffaa7e9e 38: 48 83 3b 00 cmpq $0x0,(%rbx) 3c: 0f .byte 0xf 3d: 84 .byte 0x84 3e: a6 cmpsb %es:(%rdi),%ds:(%rsi)