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: 4265 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:traverse_mounts fs/namei.c:1439 [inline] RIP: 0010:handle_mounts fs/namei.c:1551 [inline] RIP: 0010:step_into+0x11d/0xf10 fs/namei.c:1844 Code: 74 24 08 c6 44 24 7f 00 43 0f b6 04 3c 84 c0 4d 89 fd 0f 85 f5 0b 00 00 45 8b 36 4c 8b bc 24 a8 00 00 00 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 f4 0b 00 00 45 8b 3f 44 89 fe 81 e6 00 RSP: 0018:ffffc90003d67ac0 EFLAGS: 00010206 RAX: 0000000000000003 RBX: ffffc90003d67ca0 RCX: ffff88802eb89dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003d67bc8 R08: dffffc0000000000 R09: ffffed100cf61081 R10: ffffed100cf61081 R11: 1ffff1100cf61080 R12: 1ffff920007acf9b R13: dffffc0000000000 R14: 0000000000000080 R15: 0000000000000018 FS: 0000555582c50500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f050b924492 CR3: 000000005d24a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lookup_last fs/namei.c:2463 [inline] path_lookupat+0x169/0x440 fs/namei.c:2487 filename_lookup+0x1f0/0x500 fs/namei.c:2516 user_path_at_empty+0x3e/0x60 fs/namei.c:2913 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1829 [inline] __do_sys_umount fs/namespace.c:1837 [inline] __se_sys_umount fs/namespace.c:1835 [inline] __x64_sys_umount+0xf1/0x160 fs/namespace.c:1835 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: 0033:0x7f15b7790a77 Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffc1e9fb628 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f15b7790a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc1e9fb6e0 RBP: 00007ffc1e9fb6e0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc1e9fc7d0 R13: 00007f15b7813d7d R14: 0000555582c504a8 R15: 00007ffc1e9fe990 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:traverse_mounts fs/namei.c:1439 [inline] RIP: 0010:handle_mounts fs/namei.c:1551 [inline] RIP: 0010:step_into+0x11d/0xf10 fs/namei.c:1844 Code: 74 24 08 c6 44 24 7f 00 43 0f b6 04 3c 84 c0 4d 89 fd 0f 85 f5 0b 00 00 45 8b 36 4c 8b bc 24 a8 00 00 00 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 f4 0b 00 00 45 8b 3f 44 89 fe 81 e6 00 RSP: 0018:ffffc90003d67ac0 EFLAGS: 00010206 RAX: 0000000000000003 RBX: ffffc90003d67ca0 RCX: ffff88802eb89dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003d67bc8 R08: dffffc0000000000 R09: ffffed100cf61081 R10: ffffed100cf61081 R11: 1ffff1100cf61080 R12: 1ffff920007acf9b R13: dffffc0000000000 R14: 0000000000000080 R15: 0000000000000018 FS: 0000555582c50500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f050b924492 CR3: 000000005d24a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 74 24 je 0x26 2: 08 c6 or %al,%dh 4: 44 24 7f rex.R and $0x7f,%al 7: 00 43 0f add %al,0xf(%rbx) a: b6 04 mov $0x4,%dh c: 3c 84 cmp $0x84,%al e: c0 4d 89 fd rorb $0xfd,-0x77(%rbp) 12: 0f 85 f5 0b 00 00 jne 0xc0d 18: 45 8b 36 mov (%r14),%r14d 1b: 4c 8b bc 24 a8 00 00 mov 0xa8(%rsp),%r15 22: 00 23: 4c 89 f8 mov %r15,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 f4 0b 00 00 jne 0xc2b 37: 45 8b 3f mov (%r15),%r15d 3a: 44 89 fe mov %r15d,%esi 3d: 81 .byte 0x81 3e: e6 00 out %al,$0x0