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: 31391 Comm: syz.1.6892 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 : [<813acdb8>] lr : [<813acda8>] psr: 60000013 sp : e031dd30 ip : e031dd30 fp : e031dd54 r10: 82b16f40 r9 : 00000003 r8 : 8337f780 r7 : e031dd90 r6 : 8337f780 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e15684 r1 : 00000001 r0 : 813aca28 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85937b80 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 8337f780 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe031c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r8 information: slab kmalloc-192 start 8337f780 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 0xe031c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xe031c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.1.6892 (pid: 31391, stack limit = 0xe031c000) Stack: (0xe031dd30 to 0xe031e000) dd20: 823ff1e0 8337f780 829cf9ac 829cf9ac dd40: 81e15b44 8337f7c4 e031dd8c e031dd58 813a8e54 813acc50 20000180 00000000 dd60: e031dd7c 20000180 8337f780 b5403587 20000180 841c4800 40946400 00000001 dd80: e031de4c e031dd90 813a49a0 813a8d58 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00004f27 00000003 00000005 00000002 00000001 00000cc9 00000009 ddc0: 00000007 00000001 00000000 00000efb 00000001 00000006 00000001 00000006 dde0: 00000101 00001000 0001a44d 00007fff 40000007 0000009d 0000caa7 0000007f de00: 20001e58 00000004 00000e68 0000003c 0000000c 00000005 fffffffd fffffff7 de20: 00000000 e50658ed 00000000 84fc5f00 8337f780 20000180 20000180 841c4800 de40: e031df14 e031de50 813a596c 813a48ac 00000000 00000000 00000000 e50658ed de60: 00000000 00000000 8247154c 0000005f 83ee4a58 8337f7b0 83b33c24 841c4800 de80: e031dee4 e031de90 80797fbc 8078e320 00000064 00000001 00000000 e031deac dea0: 85565490 834f6bb0 00006400 0000000b e031dea0 00000000 e031dd30 e50658ed dec0: 84fc5f00 40946400 20000180 20000180 84fc5f00 00000003 e031def4 e031dee8 dee0: 807980dc e50658ed e031df14 40946400 00000000 84fc5f01 20000180 84fc5f00 df00: 00000003 841c4800 e031dfa4 e031df18 8056d084 813a539c ecac8b10 841c4800 df20: e031df3c e031df30 81a3b7f8 81a3b6c8 e031df54 e031df40 8025e490 8028f00c df40: e031dfb0 40000000 e031df84 e031df58 802229ec 8025e44c 00000000 8281cddc df60: e031dfb0 0014ca70 ecac8b10 80222940 00000000 e50658ed e031dfac 00000000 df80: 00000000 00316308 00000036 8020029c 841c4800 00000036 00000000 e031dfa8 dfa0: 80200060 8056cf60 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb80bc dfe0: 76fb7ec0 76fb7eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813acc44>] (parport_attach) from [<813a8e54>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:8337f7c4 r5:81e15b44 r4:829cf9ac [<813a8d4c>] (comedi_device_attach) from [<813a49a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000001 r9:40946400 r8:841c4800 r7:20000180 r6:b5403587 r5:8337f780 r4:20000180 [<813a48a0>] (do_devconfig_ioctl) from [<813a596c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:841c4800 r7:20000180 r6:20000180 r5:8337f780 r4:84fc5f00 [<813a5390>] (comedi_unlocked_ioctl) from [<8056d084>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a5390>] (comedi_unlocked_ioctl) from [<8056d084>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a5390>] (comedi_unlocked_ioctl) from [<8056d084>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a5390>] (comedi_unlocked_ioctl) from [<8056d084>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:841c4800 r9:00000003 r8:84fc5f00 r7:20000180 r6:84fc5f01 r5:00000000 r4:40946400 [<8056cf54>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe031dfa8 to 0xe031dff0) dfa0: 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb80bc dfe0: 76fb7ec0 76fb7eb0 000195a4 00132510 r10:00000036 r9:841c4800 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