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: 1 UID: 0 PID: 9979 Comm: syz.5.1250 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 : [<813b8158>] lr : [<813b8148>] psr: 60000013 sp : dfbedd30 ip : dfbedd30 fp : dfbedd54 r10: 82b16f20 r9 : 00000003 r8 : 841d9c00 r7 : dfbedd90 r6 : 841d9c00 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e166c4 r1 : 00000001 r0 : 813b7dc8 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85ceb0c0 DAC: 00000000 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 841d9c00 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfbec000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2610 Register r8 information: slab kmalloc-192 start 841d9c00 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 0xdfbec000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2610 Register r12 information: 2-page vmalloc region starting at 0xdfbec000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2610 Process syz.5.1250 (pid: 9979, stack limit = 0xdfbec000) Stack: (0xdfbedd30 to 0xdfbee000) dd20: 824024ec 841d9c00 829cf92c 829cf92c dd40: 81e16b84 841d9c44 dfbedd8c dfbedd58 813b41f0 813b7ff0 200000c0 00000000 dd60: dfbedd7c 200000c0 841d9c00 b5403587 200000c0 83874800 40946400 00000003 dd80: dfbede4c dfbedd90 813afd3c 813b40f4 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00004f27 00007fff 00000008 00000006 00000005 00000005 00000009 ddc0: 00000008 54c6cff3 000000fd 00000002 00008401 00000006 5da31c5d 00000006 dde0: 00000101 00000000 00000892 0000a418 40000001 00000005 0000caa3 00000008 de00: 20001e5b 00000000 00000e66 00000004 00000008 00000005 00000000 fffffff8 de20: 00000000 ed94a483 00000000 84f32e40 841d9c00 200000c0 200000c0 83874800 de40: dfbedf14 dfbede50 813b0d08 813afc48 00000000 00000000 00000000 ed94a483 de60: 00000000 00000000 82475544 0000005f 842f2448 841d9c30 8421890c 83874800 de80: dfbedee4 dfbede90 8079fd30 80796128 00000064 00000001 00000000 dfbedeac dea0: 84d5ab50 834f5aa0 00006400 0000000b dfbedea0 00000000 00000000 ed94a483 dec0: 84f32e40 40946400 200000c0 200000c0 84f32e40 00000003 dfbedef4 dfbedee8 dee0: 8079fe50 ed94a483 dfbedf14 40946400 00000000 84f32e41 200000c0 84f32e40 df00: 00000003 83874800 dfbedfa4 dfbedf18 80573398 813b0738 ecac8b10 83874800 df20: dfbedf3c dfbedf30 81a4a158 81a4a028 dfbedf54 dfbedf40 8025c288 8028d5d4 df40: dfbedfb0 40000000 dfbedf84 dfbedf58 802229ec 8025c244 00000000 8281cdf4 df60: dfbedfb0 0014ca70 ecac8b10 80222940 00000000 ed94a483 dfbedfac 00000000 df80: 00000000 00316308 00000036 8020029c 83874800 00000036 00000000 dfbedfa8 dfa0: 80200060 80573274 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f9d0bc dfe0: 76f9cec0 76f9ceb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813b7fe4>] (parport_attach) from [<813b41f0>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:841d9c44 r5:81e16b84 r4:829cf92c [<813b40e8>] (comedi_device_attach) from [<813afd3c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83874800 r7:200000c0 r6:b5403587 r5:841d9c00 r4:200000c0 [<813afc3c>] (do_devconfig_ioctl) from [<813b0d08>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83874800 r7:200000c0 r6:200000c0 r5:841d9c00 r4:84f32e40 [<813b072c>] (comedi_unlocked_ioctl) from [<80573398>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813b072c>] (comedi_unlocked_ioctl) from [<80573398>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813b072c>] (comedi_unlocked_ioctl) from [<80573398>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813b072c>] (comedi_unlocked_ioctl) from [<80573398>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83874800 r9:00000003 r8:84f32e40 r7:200000c0 r6:84f32e41 r5:00000000 r4:40946400 [<80573268>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbedfa8 to 0xdfbedff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f9d0bc dfe0: 76f9cec0 76f9ceb0 000195a4 00132510 r10:00000036 r9:83874800 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