general protection fault, probably for non-canonical address 0xdffffc0000000084: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000420-0x0000000000000427] CPU: 0 PID: 35 Comm: khugepaged Not tainted 6.7.0-rc3-next-20231128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2374 [inline] RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2506 [inline] RIP: 0010:khugepaged+0x7af/0x1420 mm/khugepaged.c:2562 Code: 00 89 de e8 a3 8a a2 ff 85 db 0f 84 77 0a 00 00 e8 26 8f a2 ff 49 8d 7d 20 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 3d 0b 00 00 49 8b 75 20 31 c9 31 d2 41 b8 01 00 RSP: 0018:ffffc90000abfce8 EFLAGS: 00010207 RAX: 0000000000000084 RBX: 0000000000000001 RCX: dffffc0000000000 RDX: ffff888018ab1dc0 RSI: ffffffff81e5863a RDI: 0000000000000426 RBP: 0000000020400000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000020800000 R13: 0000000000000406 R14: 0000000000000004 R15: 0000000000000846 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffeddbe6e68 CR3: 000000002161c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:khugepaged_scan_mm_slot mm/khugepaged.c:2374 [inline] RIP: 0010:khugepaged_do_scan mm/khugepaged.c:2506 [inline] RIP: 0010:khugepaged+0x7af/0x1420 mm/khugepaged.c:2562 Code: 00 89 de e8 a3 8a a2 ff 85 db 0f 84 77 0a 00 00 e8 26 8f a2 ff 49 8d 7d 20 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 3d 0b 00 00 49 8b 75 20 31 c9 31 d2 41 b8 01 00 RSP: 0018:ffffc90000abfce8 EFLAGS: 00010207 RAX: 0000000000000084 RBX: 0000000000000001 RCX: dffffc0000000000 RDX: ffff888018ab1dc0 RSI: ffffffff81e5863a RDI: 0000000000000426 RBP: 0000000020400000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000020800000 R13: 0000000000000406 R14: 0000000000000004 R15: 0000000000000846 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2cc22000 CR3: 0000000075a59000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 89 de mov %ebx,%esi 2: e8 a3 8a a2 ff call 0xffa28aaa 7: 85 db test %ebx,%ebx 9: 0f 84 77 0a 00 00 je 0xa86 f: e8 26 8f a2 ff call 0xffa28f3a 14: 49 8d 7d 20 lea 0x20(%r13),%rdi 18: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 1f: fc ff df 22: 48 89 f8 mov %rdi,%rax 25: 48 c1 e8 03 shr $0x3,%rax * 29: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2d: 0f 85 3d 0b 00 00 jne 0xb70 33: 49 8b 75 20 mov 0x20(%r13),%rsi 37: 31 c9 xor %ecx,%ecx 39: 31 d2 xor %edx,%edx 3b: 41 rex.B 3c: b8 .byte 0xb8 3d: 01 00 add %eax,(%rax)