8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 6663 Comm: syz.0.531 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] PC is at parport_attach+0x174/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] LR is at parport_attach+0x164/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<81408ba0>] lr : [<81408b90>] psr: 60000013 sp : dfe19d28 ip : dfe19d28 fp : dfe19d4c r10: 82b28ad8 r9 : 00000003 r8 : 84520780 r7 : dfe19d88 r6 : 84520780 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e1a2b8 r1 : 00000001 r0 : 81408810 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85ccfc40 DAC: fffffffd Register r0 information: non-slab/vmalloc memory Register r1 information: non-paged memory Register r2 information: non-slab/vmalloc memory Register r3 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 84520780 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfe18000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 84520780 pointer offset 0 size 192 Register r9 information: non-paged memory Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xdfe18000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfe18000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.531 (pid: 6663, stack limit = 0xdfe18000) Stack: (0xdfe19d28 to 0xdfe1a000) 9d20: 82432d18 84520780 829d3f08 829d3f08 81e1a778 845207c4 9d40: dfe19d84 dfe19d50 81404848 81408a38 845207b0 00000000 dfe19d74 200000c0 9d60: 84520780 b5403587 845207b0 8598b000 40946400 00000003 dfe19e44 dfe19d88 9d80: 814001a0 8140474c 656d6f63 705f6964 6f707261 00007472 00000000 00004f27 9da0: 00000002 00010000 00000005 000005f5 00000000 00010003 00000007 0000000a 9dc0: 00000001 00008001 00000004 00000c36 00000801 00000007 00000b4b 00000000 9de0: fffffffe 00000003 00000008 00000089 0000caa7 00020a03 20001e58 00c00000 9e00: 00000e6b c0000000 00000006 01000000 00000000 fffffff8 00000000 9619576a 9e20: 00000000 864bf780 84520780 200000c0 845207b0 8598b000 dfe19f14 dfe19e48 9e40: 81401194 814000ac 00000000 00000000 00000000 00000000 00000000 9619576a 9e60: 00000000 00000000 824a35ec 0000005f 84494a30 00000064 845ff12c 8598b000 9e80: dfe19ee4 dfe19e90 807b7f68 807ae48c 00000064 00000001 00000000 dfe19eac 9ea0: 85cd06d0 83421110 00006400 0000000b dfe19ea0 00000000 00000000 9619576a 9ec0: 864bf780 40946400 200000c0 200000c0 864bf780 00000004 dfe19ef4 dfe19ee8 9ee0: 807b8088 9619576a dfe19f14 40946400 00000000 864bf781 200000c0 864bf780 9f00: 00000004 8598b000 dfe19fa4 dfe19f18 805855f0 81400be4 ecac8b10 8598b000 9f20: dfe19f3c dfe19f30 81aaf80c 81aaf6dc dfe19f54 dfe19f40 8025bcbc 8028e0c4 9f40: dfe19fb0 40000000 dfe19f84 dfe19f58 80221a38 8025bc78 00000000 8281d17c 9f60: dfe19fb0 0014c8c0 ecac8b10 8022198c 00000000 9619576a dfe19fac 00000000 9f80: 00000000 00326310 00000036 8020029c 8598b000 00000036 00000000 dfe19fa8 9fa0: 80200060 805854cc 00000000 00000000 00000004 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc70bc 9fe0: 76fc6ec0 76fc6eb0 000192bc 00132360 60000010 00000004 00000000 00000000 Call trace: [<81408a2c>] (parport_attach) from [<81404848>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:845207c4 r5:81e1a778 r4:829d3f08 [<81404740>] (comedi_device_attach) from [<814001a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:8598b000 r7:845207b0 r6:b5403587 r5:84520780 r4:200000c0 [<814000a0>] (do_devconfig_ioctl) from [<81401194>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:8598b000 r7:845207b0 r6:200000c0 r5:84520780 r4:864bf780 [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8598b000 r9:00000004 r8:864bf780 r7:200000c0 r6:864bf781 r5:00000000 r4:40946400 [<805854c0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfe19fa8 to 0xdfe19ff0) 9fa0: 00000000 00000000 00000004 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc70bc 9fe0: 76fc6ec0 76fc6eb0 000192bc 00132360 r10:00000036 r9:8598b000 r8:8020029c r7:00000036 r6:00326310 r5:00000000 r4:00000000 Code: e596306c e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e596306c ldr r3, [r6, #108] @ 0x6c 4: e3a04000 mov r4, #0 8: e7f33053 ubfx r3, r3, #0, #20 c: e2433612 sub r3, r3, #18874368 @ 0x1200000 * 10: e5c34000 strb r4, [r3] <-- trapping instruction