comedi comedi0: pcl818: I/O port conflict (0x4,16) Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 0 UID: 0 PID: 5848 Comm: syz-executor349 Not tainted 6.16.0-rc4-next-20250704-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:pcl818_ai_cancel+0x69/0x3f0 drivers/comedi/drivers/pcl818.c:762 Code: 8b 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 79 ca 34 f9 48 8b 03 48 89 04 24 49 83 c4 28 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 58 ca 34 f9 4d 8b 24 24 48 83 c3 RSP: 0018:ffffc90003ee79f0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: ffff88802854df00 RCX: ffff888033bd3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802f550000 RBP: 0000000000000001 R08: ffff88802f55012f R09: 1ffff11005eaa025 R10: dffffc0000000000 R11: ffffffff88efad60 R12: 0000000000000028 R13: dffffc0000000000 R14: ffff88802f550000 R15: dffffc0000000000 FS: 000055558ba6b380(0000) GS:ffff8881257af000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000558c02111000 CR3: 0000000072048000 CR4: 00000000003526f0 Call Trace: pcl818_detach+0x66/0xd0 drivers/comedi/drivers/pcl818.c:1115 comedi_device_detach+0x134/0x720 drivers/comedi/drivers.c:207 comedi_device_attach+0x568/0x670 drivers/comedi/drivers.c:1000 do_devconfig_ioctl drivers/comedi/comedi_fops.c:855 [inline] comedi_unlocked_ioctl+0x686/0xf40 drivers/comedi/comedi_fops.c:2136 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f05c37a33e9 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd45c1fac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffd45c1fc98 RCX: 00007f05c37a33e9 RDX: 0000200000000080 RSI: 0000000040946400 RDI: 0000000000000003 RBP: 00007f05c3816610 R08: 0000000000000000 R09: 00007ffd45c1fc98 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd45c1fc88 R14: 0000000000000001 R15: 0000000000000001 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:pcl818_ai_cancel+0x69/0x3f0 drivers/comedi/drivers/pcl818.c:762 Code: 8b 1b 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 79 ca 34 f9 48 8b 03 48 89 04 24 49 83 c4 28 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 58 ca 34 f9 4d 8b 24 24 48 83 c3 RSP: 0018:ffffc90003ee79f0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: ffff88802854df00 RCX: ffff888033bd3c00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802f550000 RBP: 0000000000000001 R08: ffff88802f55012f R09: 1ffff11005eaa025 R10: dffffc0000000000 R11: ffffffff88efad60 R12: 0000000000000028 R13: dffffc0000000000 R14: ffff88802f550000 R15: dffffc0000000000 FS: 000055558ba6b380(0000) GS:ffff8881258af000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000005fdeb8 CR3: 0000000072048000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: 8b 1b mov (%rbx),%ebx 2: 48 89 d8 mov %rbx,%rax 5: 48 c1 e8 03 shr $0x3,%rax 9: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) e: 74 08 je 0x18 10: 48 89 df mov %rbx,%rdi 13: e8 79 ca 34 f9 call 0xf934ca91 18: 48 8b 03 mov (%rbx),%rax 1b: 48 89 04 24 mov %rax,(%rsp) 1f: 49 83 c4 28 add $0x28,%r12 23: 4c 89 e0 mov %r12,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 e7 mov %r12,%rdi 34: e8 58 ca 34 f9 call 0xf934ca91 39: 4d 8b 24 24 mov (%r12),%r12 3d: 48 rex.W 3e: 83 .byte 0x83 3f: c3 ret