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: 5051 Comm: syz.0.399 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 : [<813cb600>] lr : [<813cb5f0>] psr: 60000013 sp : df9f1d30 ip : df9f1d30 fp : df9f1d54 r10: 82b24900 r9 : 00000003 r8 : 83c856c0 r7 : df9f1d90 r6 : 83c856c0 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e1765c r1 : 00000001 r0 : 813cb270 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 858ffb40 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 83c856c0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r8 information: slab kmalloc-192 start 83c856c0 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 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf9f0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.399 (pid: 5051, stack limit = 0xdf9f0000) Stack: (0xdf9f1d30 to 0xdf9f2000) 1d20: 823ecc98 83c856c0 829d1b3c 829d1b3c 1d40: 81e17b1c 83c85704 df9f1d8c df9f1d58 813c768c 813cb498 200000c0 00000000 1d60: df9f1d7c 200000c0 83c856c0 b5403587 200000c0 84263c00 40946400 00000003 1d80: df9f1e4c df9f1d90 813c31d8 813c7590 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00004f27 0000000d 00000004 00000004 00000800 00000004 00000004 1dc0: 00000007 54c6cff3 00000022 00000002 00000001 00000001 00000001 00000006 1de0: 00000101 fffffffe 0000007f 00000003 40000003 00000089 0000cae3 00000000 1e00: 20001e5b 00000003 00000e66 00000003 00000008 00004086 00000000 fffffff8 1e20: 00000000 ee699ae5 00000000 84e1ba80 83c856c0 200000c0 200000c0 84263c00 1e40: df9f1f14 df9f1e50 813c41a4 813c30e4 00000000 00000000 00000000 ee699ae5 1e60: 00000000 00000000 8245d5b4 0000005f 83e23de0 83c856f0 841cfb94 84263c00 1e80: df9f1ee4 df9f1e90 807a5fa4 8079c39c 00000064 00000001 00000000 df9f1eac 1ea0: 84df5190 8342d770 00006400 0000000b df9f1ea0 00000000 00000000 ee699ae5 1ec0: 84e1ba80 40946400 200000c0 200000c0 84e1ba80 00000003 df9f1ef4 df9f1ee8 1ee0: 807a60c4 ee699ae5 df9f1f14 40946400 00000000 84e1ba81 200000c0 84e1ba80 1f00: 00000003 84263c00 df9f1fa4 df9f1f18 80577dc8 813c3bd4 ecac8b10 84263c00 1f20: df9f1f3c df9f1f30 81a36298 81a36168 df9f1f54 df9f1f40 8025c478 8028d90c 1f40: df9f1fb0 40000000 df9f1f84 df9f1f58 802229ec 8025c434 00000000 8281cf74 1f60: df9f1fb0 0014ca70 ecac8b10 80222940 00000000 ee699ae5 df9f1fac 00000000 1f80: 00000000 00316308 00000036 8020029c 84263c00 00000036 00000000 df9f1fa8 1fa0: 80200060 80577ca4 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f870bc 1fe0: 76f86ec0 76f86eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813cb48c>] (parport_attach) from [<813c768c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:83c85704 r5:81e17b1c r4:829d1b3c [<813c7584>] (comedi_device_attach) from [<813c31d8>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84263c00 r7:200000c0 r6:b5403587 r5:83c856c0 r4:200000c0 [<813c30d8>] (do_devconfig_ioctl) from [<813c41a4>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:84263c00 r7:200000c0 r6:200000c0 r5:83c856c0 r4:84e1ba80 [<813c3bc8>] (comedi_unlocked_ioctl) from [<80577dc8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c3bc8>] (comedi_unlocked_ioctl) from [<80577dc8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c3bc8>] (comedi_unlocked_ioctl) from [<80577dc8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c3bc8>] (comedi_unlocked_ioctl) from [<80577dc8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84263c00 r9:00000003 r8:84e1ba80 r7:200000c0 r6:84e1ba81 r5:00000000 r4:40946400 [<80577c98>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9f1fa8 to 0xdf9f1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f870bc 1fe0: 76f86ec0 76f86eb0 000195a4 00132510 r10:00000036 r9:84263c00 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