8<--- cut here --- Unable to handle kernel paging request at virtual address fee00d00 when write [fee00d00] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 6878 Comm: syz.1.1113 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: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 : [<8145b55c>] lr : [<8145b54c>] psr: 60000013 sp : dfb09d30 ip : dfb09d30 fp : dfb09d54 r10: 82d29754 r9 : 00000003 r8 : 84644300 r7 : dfb09d90 r6 : 84644300 r5 : 00000000 r4 : 00000000 r3 : fee00d00 r2 : 81e27308 r1 : 00000001 r0 : 8145b1bc Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 865887c0 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:1048 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 84644300 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfb08000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r8 information: slab kmalloc-192 start 84644300 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 0xdfb08000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Register r12 information: 2-page vmalloc region starting at 0xdfb08000 allocated at kernel_clone+0xc4/0x444 kernel/fork.c:2722 Process syz.1.1113 (pid: 6878, stack limit = 0xdfb08000) Stack: (0xdfb09d30 to 0xdfb0a000) 9d20: 824bca04 84644300 00000000 82bd2268 9d40: 81e277c8 00000000 dfb09d8c dfb09d58 814570d8 8145b3e4 40946400 00000000 9d60: dfb09d7c 20000180 84644300 b5403587 40946400 00000003 00000003 83fc1900 9d80: dfb09e4c dfb09d90 814528e4 81456fdc 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 00000d00 00000006 00000006 00000fff 00000003 00000cc7 00000000 9dc0: 00000006 00000005 000100ff 00000002 00000001 00000001 00000002 00000009 9de0: 00000003 0bc761c6 00000009 00000042 40000003 00000ffe 00000008 00000005 9e00: 0a000006 0000800b 00000032 00000005 00000002 0000000d 00000002 ffffff5c 9e20: 00000000 9e85e262 00000000 838dab80 84644300 20000180 40946400 00000003 9e40: dfb09f14 dfb09e50 81453c08 8145281c 00000000 9e85e262 00000000 00000000 9e60: 82531804 dfb09ea4 0000005f 8415a5e0 00000064 84644330 dfb09ee4 dfb09e88 9e80: 807ea79c 807e0ab0 00000064 00000001 00000000 dfb09ea4 830e9790 834e9550 9ea0: 00006400 0000000b dfb09e98 00000000 00000000 9e85e262 00000000 838dab80 9ec0: 40946400 20000180 20000180 838dab80 00000003 83fc1900 dfb09ef4 dfb09ee8 9ee0: 807ea8d0 9e85e262 dfb09f14 00000000 838dab81 40946400 20000180 838dab80 9f00: 00000003 83fc1900 dfb09fa4 dfb09f18 805a20fc 814538c0 ecac8b10 83fc1900 9f20: dfb09f3c dfb09f30 81b1ad34 81b1ac00 dfb09f54 dfb09f40 8025a6ac 8028e294 9f40: dfb09fb0 40000000 dfb09f84 dfb09f58 80220be0 8025a668 00000000 82a1c63c 9f60: dfb09fb0 0013e9b0 ecac8b10 80220b34 00000000 9e85e262 dfb09fac 00000000 9f80: 00000000 00346310 00000036 8020029c 83fc1900 00000036 00000000 dfb09fa8 9fa0: 80200060 805a1ec4 00000000 00000000 00000003 40946400 20000180 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f2c0dc 9fe0: 76f2be88 76f2be78 00018ebc 00130810 60000010 00000003 00000000 00000000 Call trace: [<8145b3d8>] (parport_attach) from [<814570d8>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e277c8 r4:82bd2268 [<81456fd0>] (comedi_device_attach) from [<814528e4>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:83fc1900 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:84644300 r4:20000180 [<81452810>] (do_devconfig_ioctl) from [<81453c08>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000180 r5:84644300 r4:838dab80 [<814538b4>] (comedi_unlocked_ioctl) from [<805a20fc>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814538b4>] (comedi_unlocked_ioctl) from [<805a20fc>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814538b4>] (comedi_unlocked_ioctl) from [<805a20fc>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814538b4>] (comedi_unlocked_ioctl) from [<805a20fc>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83fc1900 r9:00000003 r8:838dab80 r7:20000180 r6:40946400 r5:838dab81 r4:00000000 [<805a1eb8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb09fa8 to 0xdfb09ff0) 9fa0: 00000000 00000000 00000003 40946400 20000180 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f2c0dc 9fe0: 76f2be88 76f2be78 00018ebc 00130810 r10:00000036 r9:83fc1900 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