8<--- cut here --- Unable to handle kernel paging request at virtual address fee00100 when write [fee00100] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 14972 Comm: syz.8.1964 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:291 [inline] PC is at parport_attach+0x184/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:291 [inline] LR is at parport_attach+0x174/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<81470e2c>] lr : [<81470e1c>] psr: 60000013 sp : df9cdd30 ip : df9cdd30 fp : df9cdd54 r10: 82d2c9fc r9 : 00000003 r8 : 8301a540 r7 : df9cdd90 r6 : 8301a540 r5 : 00000000 r4 : 00000000 r3 : fee00100 r2 : 81e2cd88 r1 : 00000001 r0 : 81470a8c Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85b8d600 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:1048 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 8301a540 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9cc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Register r8 information: slab kmalloc-192 start 8301a540 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 0xdf9cc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Register r12 information: 2-page vmalloc region starting at 0xdf9cc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Process syz.8.1964 (pid: 14972, stack limit = 0xdf9cc000) Stack: (0xdf9cdd30 to 0xdf9ce000) dd20: 824c8958 8301a540 82bd5ce8 82bd5ce8 dd40: 81e2d248 00000000 df9cdd8c df9cdd58 8146c9a8 81470cb4 40946400 00000000 dd60: df9cdd7c 200000c0 8301a540 b5403587 40946400 00000003 00000003 8398bd40 dd80: df9cde4c df9cdd90 814681b4 8146c8ac 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00000100 80000000 00000002 00000010 0000000e 00000005 00000079 ddc0: 00000003 00080008 00000000 00000007 00000001 00000007 00000001 00000005 dde0: 000000fd fffffffb 0000000d 00000003 7fffffff ffffffff 00000004 00000000 de00: 00000003 ffffffff 0000f39e 00000003 00000008 00000006 00000000 fffffff8 de20: 00000000 068aba58 00000000 86970000 8301a540 200000c0 40946400 00000003 de40: df9cdf14 df9cde50 814694d8 814680ec 00000000 068aba58 00000000 00000000 de60: 8253d804 df9cdea4 0000005f 844c6d40 00000064 8301a570 df9cdee4 df9cde88 de80: 807fbdcc 807f20fc 00000064 00000001 00000000 df9cdea4 85bdd310 834e7440 dea0: 00006400 0000000b df9cde98 00000000 00000000 068aba58 00000000 86970000 dec0: 40946400 200000c0 200000c0 86970000 00000003 8398bd40 df9cdef4 df9cdee8 dee0: 807fbf00 068aba58 df9cdf14 00000000 86970001 40946400 200000c0 86970000 df00: 00000003 8398bd40 df9cdfa4 df9cdf18 805b294c 81469190 ecac8b10 8398bd40 df20: df9cdf3c df9cdf30 81b33604 81b334d0 df9cdf54 df9cdf40 8025a7e8 8028e4c0 df40: df9cdfb0 40000000 df9cdf84 df9cdf58 80220bdc 8025a7a4 00000000 82a1ea8c df60: df9cdfb0 0013e9c0 ecac8b10 80220b30 00000000 068aba58 df9cdfac 00000000 df80: 00000000 00346310 00000036 8020029c 8398bd40 00000036 00000000 df9cdfa8 dfa0: 80200060 805b2714 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f3c0dc dfe0: 76f3be88 76f3be78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81470ca8>] (parport_attach) from [<8146c9a8>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2d248 r4:82bd5ce8 [<8146c8a0>] (comedi_device_attach) from [<814681b4>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:8398bd40 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:8301a540 r4:200000c0 [<814680e0>] (do_devconfig_ioctl) from [<814694d8>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:200000c0 r5:8301a540 r4:86970000 [<81469184>] (comedi_unlocked_ioctl) from [<805b294c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81469184>] (comedi_unlocked_ioctl) from [<805b294c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81469184>] (comedi_unlocked_ioctl) from [<805b294c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81469184>] (comedi_unlocked_ioctl) from [<805b294c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8398bd40 r9:00000003 r8:86970000 r7:200000c0 r6:40946400 r5:86970001 r4:00000000 [<805b2708>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9cdfa8 to 0xdf9cdff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f3c0dc dfe0: 76f3be88 76f3be78 00018ebc 00130820 r10:00000036 r9:8398bd40 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e5963064 e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e5963064 ldr r3, [r6, #100] @ 0x64 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