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: 5388 Comm: syz.1.356 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 : [<813cbe98>] lr : [<813cbe88>] psr: 60000013 sp : df9ddd30 ip : df9ddd30 fp : df9ddd54 r10: 82b23f20 r9 : 00000003 r8 : 841b4540 r7 : df9ddd90 r6 : 841b4540 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e1793c r1 : 00000001 r0 : 813cbb08 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84ce7440 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 841b4540 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r8 information: slab kmalloc-192 start 841b4540 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 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.356 (pid: 5388, stack limit = 0xdf9dc000) Stack: (0xdf9ddd30 to 0xdf9de000) dd20: 82402c1c 841b4540 829d1b2c 829d1b2c dd40: 81e17dfc 841b4584 df9ddd8c df9ddd58 813c7f28 813cbd30 200000c0 00000000 dd60: df9ddd7c 200000c0 841b4540 b5403587 200000c0 84bf6c00 40946400 00000003 dd80: df9dde4c df9ddd90 813c3a74 813c7e2c 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00004f27 0000000d 00000004 00000004 00000800 00000004 00000004 ddc0: 00000007 54c6cff3 00000022 00000002 00000001 00000001 00000001 00000006 dde0: 00000101 fffffffe 0000007f 00000003 40000003 00000089 0000cae3 00000000 de00: 20001e5b 00000003 00000e66 00000003 00000008 00004086 00000000 fffffff8 de20: 00000000 5ba7e476 00000000 85b4f900 841b4540 200000c0 200000c0 84bf6c00 de40: df9ddf14 df9dde50 813c4a40 813c3980 00000000 00000000 00000000 5ba7e476 de60: 00000000 00000000 824755b4 0000005f 84115600 841b4570 841de7ec 84bf6c00 de80: df9ddee4 df9dde90 807a98fc 8079fcf4 00000064 00000001 00000000 df9ddeac dea0: 85aa40d0 834e6198 00006400 0000000b df9ddea0 00000000 00000000 5ba7e476 dec0: 85b4f900 40946400 200000c0 200000c0 85b4f900 00000003 df9ddef4 df9ddee8 dee0: 807a9a1c 5ba7e476 df9ddf14 40946400 00000000 85b4f901 200000c0 85b4f900 df00: 00000003 84bf6c00 df9ddfa4 df9ddf18 8057b748 813c4470 ecac8b10 84bf6c00 df20: df9ddf3c df9ddf30 81a42bb8 81a42a88 df9ddf54 df9ddf40 8025c478 8028d90c df40: df9ddfb0 40000000 df9ddf84 df9ddf58 802229ec 8025c434 00000000 8281ccf4 df60: df9ddfb0 0014ca70 ecac8b10 80222940 00000000 5ba7e476 df9ddfac 00000000 df80: 00000000 00316308 00000036 8020029c 84bf6c00 00000036 00000000 df9ddfa8 dfa0: 80200060 8057b624 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f830bc dfe0: 76f82ec0 76f82eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813cbd24>] (parport_attach) from [<813c7f28>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:841b4584 r5:81e17dfc r4:829d1b2c [<813c7e20>] (comedi_device_attach) from [<813c3a74>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84bf6c00 r7:200000c0 r6:b5403587 r5:841b4540 r4:200000c0 [<813c3974>] (do_devconfig_ioctl) from [<813c4a40>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:84bf6c00 r7:200000c0 r6:200000c0 r5:841b4540 r4:85b4f900 [<813c4464>] (comedi_unlocked_ioctl) from [<8057b748>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c4464>] (comedi_unlocked_ioctl) from [<8057b748>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c4464>] (comedi_unlocked_ioctl) from [<8057b748>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c4464>] (comedi_unlocked_ioctl) from [<8057b748>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84bf6c00 r9:00000003 r8:85b4f900 r7:200000c0 r6:85b4f901 r5:00000000 r4:40946400 [<8057b618>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9ddfa8 to 0xdf9ddff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f830bc dfe0: 76f82ec0 76f82eb0 000195a4 00132510 r10:00000036 r9:84bf6c00 r8:8020029c r7:00000036 r6:00316308 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