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: 4754 Comm: syz.1.261 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 : [<813ab660>] lr : [<813ab650>] psr: 60000013 sp : df981d30 ip : df981d30 fp : df981d54 r10: 82b16f00 r9 : 00000003 r8 : 841aa240 r7 : df981d90 r6 : 841aa240 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e15364 r1 : 00000001 r0 : 813ab2d0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85a13140 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 841aa240 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf980000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r8 information: slab kmalloc-192 start 841aa240 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 0xdf980000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdf980000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.1.261 (pid: 4754, stack limit = 0xdf980000) Stack: (0xdf981d30 to 0xdf982000) 1d20: 82b16f00 df981d8c df981d58 829cf92c 1d40: 81e15824 841aa284 df981d8c df981d58 813a76f8 813ab4f8 200000c0 00000000 1d60: df981d7c 200000c0 841aa240 b5403587 200000c0 85663c00 40946400 00000003 1d80: df981e4c df981d90 813a3278 813a75fc 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00004f27 00000000 00000008 00000006 00000005 00000005 00000009 1dc0: 00000007 54c6cff3 000000fd 00000002 00008401 00000006 5da31c5d 00000006 1de0: 00000101 00000000 00000892 0000a418 40000001 00000005 0000caa3 00000008 1e00: 20001e5b 00000000 00000e66 00000004 00000008 00000005 00000000 fffffff8 1e20: 00000000 fe1e6e76 00000000 84867e40 841aa240 200000c0 200000c0 85663c00 1e40: df981f14 df981e50 813a4244 813a3184 00000000 00000000 00000000 fe1e6e76 1e60: 00000000 00000000 8247054c 0000005f 83e9e858 841aa270 83e72cb4 85663c00 1e80: df981ee4 df981e90 807979b4 8078dd18 00000064 00000001 00000000 df981eac 1ea0: 8534e490 83413550 00006400 0000000b df981ea0 00000000 00000000 fe1e6e76 1ec0: 84867e40 40946400 200000c0 200000c0 84867e40 00000003 df981ef4 df981ee8 1ee0: 80797ad4 fe1e6e76 df981f14 40946400 00000000 84867e41 200000c0 84867e40 1f00: 00000003 85663c00 df981fa4 df981f18 8056cd60 813a3c74 ecac8b10 85663c00 1f20: df981f3c df981f30 81a394b8 81a39388 df981f54 df981f40 8025e490 8028ef64 1f40: df981fb0 40000000 df981f84 df981f58 802229ec 8025e44c 00000000 8281cddc 1f60: df981fb0 0014c820 ecac8b10 80222940 00000000 fe1e6e76 df981fac 00000000 1f80: 00000000 002f6308 00000036 8020029c 85663c00 00000036 00000000 df981fa8 1fa0: 80200060 8056cc3c 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fd60bc 1fe0: 76fd5ec0 76fd5eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813ab4ec>] (parport_attach) from [<813a76f8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r6:841aa284 r5:81e15824 r4:829cf92c [<813a75f0>] (comedi_device_attach) from [<813a3278>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:85663c00 r7:200000c0 r6:b5403587 r5:841aa240 r4:200000c0 [<813a3178>] (do_devconfig_ioctl) from [<813a4244>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:85663c00 r7:200000c0 r6:200000c0 r5:841aa240 r4:84867e40 [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a3c68>] (comedi_unlocked_ioctl) from [<8056cd60>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:85663c00 r9:00000003 r8:84867e40 r7:200000c0 r6:84867e41 r5:00000000 r4:40946400 [<8056cc30>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf981fa8 to 0xdf981ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fd60bc 1fe0: 76fd5ec0 76fd5eb0 0001948c 001322c0 r10:00000036 r9:85663c00 r8:8020029c r7:00000036 r6:002f6308 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