EXT4-fs error (device loop2): ext4_orphan_get:1409: comm syz.2.1048: couldn't read orphan inode 15 (err -117) EXT4-fs (loop2): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 1 PID: 10307 Comm: syz.2.1048 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:utf8nlookup+0x39/0xa50 fs/unicode/utf8-norm.c:306 Code: 89 44 24 10 49 89 ce 48 89 14 24 89 f5 49 89 fd 49 bf 00 00 00 00 00 fc ff df e8 02 4d f4 fe 49 8d 5d 18 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 38 88 4c ff 48 8b 1b 48 83 c3 30 RSP: 0018:ffffc9000b9c74e0 EFLAGS: 00010206 RAX: 0000000000000003 RBX: 0000000000000018 RCX: 0000000000080000 RDX: ffffc9000d9cd000 RSI: 00000000000004a7 RDI: 00000000000004a8 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: ffffc9000b9c7678 R11: fffff52001738ed2 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88805c2c0650 R15: dffffc0000000000 FS: 00007fed827936c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000031fa0000 CR4: 00000000003506e0 DR0: 0000000000000004 DR1: 0000000000000000 DR2: 000000000000000a DR3: 0000000000000800 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: utf8byte+0x34f/0x1370 fs/unicode/utf8-norm.c:-1 utf8_casefold+0x146/0x260 fs/unicode/utf8-core.c:109 ext4_fname_setup_ci_filename+0x1d5/0x430 fs/ext4/namei.c:1463 ext4_fname_prepare_lookup+0x230/0x3d0 fs/ext4/crypto.c:55 ext4_lookup_entry fs/ext4/namei.c:1767 [inline] ext4_lookup+0x125/0x710 fs/ext4/namei.c:1842 __lookup_slow+0x2a1/0x400 fs/namei.c:1702 lookup_slow+0x53/0x70 fs/namei.c:1719 walk_component+0x2be/0x3f0 fs/namei.c:2010 lookup_last fs/namei.c:2467 [inline] path_lookupat+0x169/0x440 fs/namei.c:2491 filename_lookup+0x228/0x560 fs/namei.c:2520 user_path_at_empty+0x42/0x60 fs/namei.c:2917 user_path_at include/linux/namei.h:57 [inline] do_mount fs/namespace.c:3723 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2a8/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fed8199ce59 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:00007fed82793028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fed81c15fa0 RCX: 00007fed8199ce59 RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000000 RBP: 00007fed81a32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fed81c16038 R14: 00007fed81c15fa0 R15: 00007ffde2cc50a8 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:utf8nlookup+0x39/0xa50 fs/unicode/utf8-norm.c:306 Code: 89 44 24 10 49 89 ce 48 89 14 24 89 f5 49 89 fd 49 bf 00 00 00 00 00 fc ff df e8 02 4d f4 fe 49 8d 5d 18 48 89 d8 48 c1 e8 03 <42> 80 3c 38 00 74 08 48 89 df e8 38 88 4c ff 48 8b 1b 48 83 c3 30 RSP: 0018:ffffc9000b9c74e0 EFLAGS: 00010206 RAX: 0000000000000003 RBX: 0000000000000018 RCX: 0000000000080000 RDX: ffffc9000d9cd000 RSI: 00000000000004a7 RDI: 00000000000004a8 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: ffffc9000b9c7678 R11: fffff52001738ed2 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88805c2c0650 R15: dffffc0000000000 FS: 00007fed827936c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f131e972000 CR3: 0000000031fa0000 CR4: 00000000003506e0 DR0: 0000000000000004 DR1: 0000000000000000 DR2: 000000000000000a DR3: 0000000000000800 DR6: 00000000ffff0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 89 44 24 10 mov %eax,0x10(%rsp) 4: 49 89 ce mov %rcx,%r14 7: 48 89 14 24 mov %rdx,(%rsp) b: 89 f5 mov %esi,%ebp d: 49 89 fd mov %rdi,%r13 10: 49 bf 00 00 00 00 00 movabs $0xdffffc0000000000,%r15 17: fc ff df 1a: e8 02 4d f4 fe call 0xfef44d21 1f: 49 8d 5d 18 lea 0x18(%r13),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 48 89 df mov %rbx,%rdi 34: e8 38 88 4c ff call 0xff4c8871 39: 48 8b 1b mov (%rbx),%rbx 3c: 48 83 c3 30 add $0x30,%rbx