8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f23 when write [fee04f23] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 7754 Comm: syz.2.816 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 : [<81408a10>] lr : [<81408a00>] psr: 60000013 sp : dfb7dd28 ip : dfb7dd28 fp : dfb7dd4c r10: 82b28ad8 r9 : 00000003 r8 : 844ac300 r7 : dfb7dd88 r6 : 844ac300 r5 : 00000000 r4 : 00000000 r3 : fee04f23 r2 : 81e1a2b8 r1 : 00000001 r0 : 81408680 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 863cb840 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 844ac300 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfb7c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r8 information: slab kmalloc-192 start 844ac300 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 0xdfb7c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfb7c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.2.816 (pid: 7754, stack limit = 0xdfb7c000) Stack: (0xdfb7dd28 to 0xdfb7e000) dd20: 82432cf4 844ac300 829d3f08 829d3f08 81e1a778 844ac344 dd40: dfb7dd84 dfb7dd50 814046b8 814088a8 844ac330 00000000 dfb7dd74 200000c0 dd60: 844ac300 b5403587 844ac330 85188000 40946400 00000003 dfb7de44 dfb7dd88 dd80: 81400010 814045bc 656d6f63 705f6964 6f707261 00007472 00000000 00004f23 dda0: 00000005 00000002 04000401 00000001 40000cc7 00000fff 5c952399 00000005 ddc0: 000003ff 00000802 00000008 00010001 00000001 00000009 0000e1cb 00000006 dde0: 00000401 00000003 00000395 80000089 fffffffd 00000032 fffffff5 ffffeadb de00: 00000007 0000003c 00000008 00000003 08000000 00002ec0 00000000 18d2de58 de20: 00000000 8506a600 844ac300 200000c0 844ac330 85188000 dfb7df14 dfb7de48 de40: 81401004 813fff1c 00000000 00000000 00000000 00000000 00000000 18d2de58 de60: 00000000 00000000 824a35ec 0000005f 8403b210 00000064 844b97a4 85188000 de80: dfb7dee4 dfb7de90 807b7dd8 807ae2fc 00000064 00000001 00000000 dfb7deac dea0: 84fd9b50 834ea2a8 00006400 0000000b dfb7dea0 00000000 00000000 18d2de58 dec0: 8506a600 40946400 200000c0 200000c0 8506a600 00000003 dfb7def4 dfb7dee8 dee0: 807b7ef8 18d2de58 dfb7df14 40946400 00000000 8506a601 200000c0 8506a600 df00: 00000003 85188000 dfb7dfa4 dfb7df18 80585574 81400a54 ecac8b10 85188000 df20: dfb7df3c dfb7df30 81aaf4bc 81aaf38c dfb7df54 dfb7df40 8025bcbc 8028e0c4 df40: dfb7dfb0 40000000 dfb7df84 dfb7df58 80221a38 8025bc78 00000000 8281d17c df60: dfb7dfb0 0014c880 ecac8b10 8022198c 00000000 18d2de58 dfb7dfac 00000000 df80: 00000000 00316310 00000036 8020029c 85188000 00000036 00000000 dfb7dfa8 dfa0: 80200060 80585450 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316310 00000036 00300000 00000000 00006364 76fd10bc dfe0: 76fd0ec0 76fd0eb0 0001929c 00132320 60000010 00000003 00000000 00000000 Call trace: [<8140889c>] (parport_attach) from [<814046b8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r6:844ac344 r5:81e1a778 r4:829d3f08 [<814045b0>] (comedi_device_attach) from [<81400010>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:85188000 r7:844ac330 r6:b5403587 r5:844ac300 r4:200000c0 [<813fff10>] (do_devconfig_ioctl) from [<81401004>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:85188000 r7:844ac330 r6:200000c0 r5:844ac300 r4:8506a600 [<81400a48>] (comedi_unlocked_ioctl) from [<80585574>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400a48>] (comedi_unlocked_ioctl) from [<80585574>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400a48>] (comedi_unlocked_ioctl) from [<80585574>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400a48>] (comedi_unlocked_ioctl) from [<80585574>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:85188000 r9:00000003 r8:8506a600 r7:200000c0 r6:8506a601 r5:00000000 r4:40946400 [<80585444>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb7dfa8 to 0xdfb7dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316310 00000036 00300000 00000000 00006364 76fd10bc dfe0: 76fd0ec0 76fd0eb0 0001929c 00132320 r10:00000036 r9:85188000 r8:8020029c r7:00000036 r6:00316310 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