general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 0 PID: 334 Comm: syz-executor.0 Not tainted 6.1.134-syzkaller-1169264-ga0fa2316cce1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:traverse_mounts fs/namei.c:1430 [inline] RIP: 0010:handle_mounts fs/namei.c:1542 [inline] RIP: 0010:step_into+0x11d/0xf30 fs/namei.c:1835 Code: 74 24 08 c6 44 24 7f 00 43 0f b6 04 3c 84 c0 4d 89 fd 0f 85 08 0c 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 07 0c 00 00 45 8b 3f 44 89 fe 81 e6 00 RSP: 0018:ffffc90001397a40 EFLAGS: 00010207 RAX: 0000000000000003 RBX: ffffc90001397c80 RCX: ffff88811284a880 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001397b58 R08: dffffc0000000000 R09: ffffed102318befd R10: ffffed102318befd R11: 1ffff1102318befc R12: 1ffff92000272f97 R13: dffffc0000000000 R14: 0000000000000081 R15: 000000000000001e FS: 00007f22d6aae6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f22d6a8cfa8 CR3: 00000001249df000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: walk_component+0x24c/0x420 fs/namei.c:2003 lookup_last fs/namei.c:2454 [inline] path_lookupat+0x180/0x490 fs/namei.c:2478 filename_lookup+0x1f0/0x500 fs/namei.c:2507 user_path_at_empty+0x47/0x1c0 fs/namei.c:2904 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1822 [inline] __do_sys_umount fs/namespace.c:1830 [inline] __se_sys_umount fs/namespace.c:1828 [inline] __x64_sys_umount+0xf1/0x160 fs/namespace.c:1828 x64_sys_call+0x86a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:167 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: 0033:0x7f22d5c7cae9 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:00007f22d6aae0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f22d5d9bf80 RCX: 00007f22d5c7cae9 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000020000080 RBP: 00007f22d5cc847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f22d5d9bf80 R15: 00007ffcee203988 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:traverse_mounts fs/namei.c:1430 [inline] RIP: 0010:handle_mounts fs/namei.c:1542 [inline] RIP: 0010:step_into+0x11d/0xf30 fs/namei.c:1835 Code: 74 24 08 c6 44 24 7f 00 43 0f b6 04 3c 84 c0 4d 89 fd 0f 85 08 0c 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 07 0c 00 00 45 8b 3f 44 89 fe 81 e6 00 RSP: 0018:ffffc90001397a40 EFLAGS: 00010207 RAX: 0000000000000003 RBX: ffffc90001397c80 RCX: ffff88811284a880 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001397b58 R08: dffffc0000000000 R09: ffffed102318befd R10: ffffed102318befd R11: 1ffff1102318befc R12: 1ffff92000272f97 R13: dffffc0000000000 R14: 0000000000000081 R15: 000000000000001e FS: 00007f22d6aae6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005556f35ca078 CR3: 00000001249df000 CR4: 00000000003506a0 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 08 0c 00 00 jne 0xc20 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 07 0c 00 00 jne 0xc3e 37: 45 8b 3f mov (%r15),%r15d 3a: 44 89 fe mov %r15d,%esi 3d: 81 .byte 0x81 3e: e6 00 out %al,$0x0