BUG: unable to handle page fault for address: ffffdc0000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 11826067 P4D 11826067 PUD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 1090 Comm: kworker/u4:2 Not tainted 5.19.0-next-20220811-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:strnlen+0x3b/0x70 lib/string.c:504 Code: 74 3c 48 bb 00 00 00 00 00 fc ff df 49 89 fc 48 89 f8 eb 09 48 83 c0 01 48 39 e8 74 1e 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 <0f> b6 14 1a 38 ca 7f 04 84 d2 75 11 80 38 00 75 d9 4c 29 e0 48 83 RSP: 0000:ffffc90005397e50 EFLAGS: 00010246 RAX: ffff000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 1fffe00000000000 RSI: 0000000000020000 RDI: ffff000000000000 RBP: ffff000000020000 R08: 0000000000000006 R09: 0000000000200000 R10: 0000000000000040 R11: 0000000000000000 R12: ffff000000000000 R13: ffff8880206b3300 R14: ffff000000000000 R15: ffff88801f303800 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffdc0000000000 CR3: 000000000bc8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: strnlen include/linux/fortify-string.h:119 [inline] copy_string_kernel+0x26/0x250 fs/exec.c:616 kernel_execve+0x2d6/0x500 fs/exec.c:1993 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Modules linked in: CR2: ffffdc0000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:strnlen+0x3b/0x70 lib/string.c:504 Code: 74 3c 48 bb 00 00 00 00 00 fc ff df 49 89 fc 48 89 f8 eb 09 48 83 c0 01 48 39 e8 74 1e 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 <0f> b6 14 1a 38 ca 7f 04 84 d2 75 11 80 38 00 75 d9 4c 29 e0 48 83 RSP: 0000:ffffc90005397e50 EFLAGS: 00010246 RAX: ffff000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 1fffe00000000000 RSI: 0000000000020000 RDI: ffff000000000000 RBP: ffff000000020000 R08: 0000000000000006 R09: 0000000000200000 R10: 0000000000000040 R11: 0000000000000000 R12: ffff000000000000 R13: ffff8880206b3300 R14: ffff000000000000 R15: ffff88801f303800 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffdc0000000000 CR3: 000000000bc8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 74 3c je 0x3e 2: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 9: fc ff df c: 49 89 fc mov %rdi,%r12 f: 48 89 f8 mov %rdi,%rax 12: eb 09 jmp 0x1d 14: 48 83 c0 01 add $0x1,%rax 18: 48 39 e8 cmp %rbp,%rax 1b: 74 1e je 0x3b 1d: 48 89 c2 mov %rax,%rdx 20: 48 89 c1 mov %rax,%rcx 23: 48 c1 ea 03 shr $0x3,%rdx 27: 83 e1 07 and $0x7,%ecx * 2a: 0f b6 14 1a movzbl (%rdx,%rbx,1),%edx <-- trapping instruction 2e: 38 ca cmp %cl,%dl 30: 7f 04 jg 0x36 32: 84 d2 test %dl,%dl 34: 75 11 jne 0x47 36: 80 38 00 cmpb $0x0,(%rax) 39: 75 d9 jne 0x14 3b: 4c 29 e0 sub %r12,%rax 3e: 48 rex.W 3f: 83 .byte 0x83