8<--- cut here --- Unable to handle kernel paging request at virtual address fee00400 when write [fee00400] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 4078 Comm: syz.2.17 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 : [<8144de6c>] lr : [<8144de5c>] psr: 60000013 sp : df9b5d30 ip : df9b5d30 fp : df9b5d54 r10: 82d2bdc4 r9 : 00000003 r8 : 8301fe40 r7 : df9b5d90 r6 : 8301fe40 r5 : 00000000 r4 : 00000000 r3 : fee00400 r2 : 81e27468 r1 : 00000001 r0 : 8144dacc Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85fb4600 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 8301fe40 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdf9b4000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Register r8 information: slab kmalloc-192 start 8301fe40 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 0xdf9b4000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Register r12 information: 2-page vmalloc region starting at 0xdf9b4000 allocated at kernel_clone+0xbc/0x438 kernel/fork.c:2721 Process syz.2.17 (pid: 4078, stack limit = 0xdf9b4000) Stack: (0xdf9b5d30 to 0xdf9b6000) 5d20: 824ba914 8301fe40 00000000 82bd27a0 5d40: 81e27928 00000000 df9b5d8c df9b5d58 814499cc 8144dcf4 40946400 00000000 5d60: df9b5d7c 20000140 8301fe40 b5403587 40946400 00000001 00000003 833e3100 5d80: df9b5e4c df9b5d90 814451d8 814498d0 656d6f63 705f6964 6f707261 00007472 5da0: 00000000 00000400 00000002 7fffffff 000084e1 0000002f 00002006 00000006 5dc0: 00000008 000a0ffa 00000000 00000007 00000002 00001003 01000004 0000000f 5de0: 00010000 ffffffa8 7ffbfffd 000001ff 0000ecd0 00000010 0003fffe 00000008 5e00: 00000007 0000746f 00000004 00000005 00000408 00000004 00000000 00007ffd 5e20: 00000000 36e59803 00000000 851b1400 8301fe40 20000140 40946400 00000001 5e40: df9b5f14 df9b5e50 814464fc 81445110 00000000 36e59803 00000000 00000000 5e60: 8252f804 df9b5ea4 0000005f 847174a0 00000064 8301fe70 df9b5ee4 df9b5e88 5e80: 807df0b0 807d53c4 00000064 00000001 00000000 df9b5ea4 830ea190 834eaf68 5ea0: 00006400 0000000b df9b5e98 00000000 00000000 36e59803 df9b5f24 851b1400 5ec0: 40946400 20000140 20000140 851b1400 00000003 833e3100 df9b5ef4 df9b5ee8 5ee0: 807df1e4 36e59803 df9b5f14 00000000 851b1400 40946400 20000140 851b1400 5f00: 00000003 833e3100 df9b5fa4 df9b5f18 8059c1ac 814461b4 df9b5f4c df9b5f28 5f20: 8034da5c 80350e30 802330dc 804ebea0 df9b5f54 df9b5f40 8025a49c 00000004 5f40: df9b5fa4 df9b5f50 8034e38c 8034d998 00000000 00000004 ffffffff 80232ec0 5f60: 00000000 00000000 00000000 00000000 00000000 36e59803 df9b5fac 00000000 5f80: 00000000 00346310 00000036 8020029c 833e3100 00000036 00000000 df9b5fa8 5fa0: 80200060 8059bf74 00000000 00000000 00000003 40946400 20000140 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 003462d8 003462e4 5fe0: 7efe2790 7efe2780 00018e58 001307a0 60000010 00000003 00000000 00000000 Call trace: [<8144dce8>] (parport_attach) from [<814499cc>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e27928 r4:82bd27a0 [<814498c4>] (comedi_device_attach) from [<814451d8>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:833e3100 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:8301fe40 r4:20000140 [<81445104>] (do_devconfig_ioctl) from [<814464fc>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:20000140 r5:8301fe40 r4:851b1400 [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814461a8>] (comedi_unlocked_ioctl) from [<8059c1ac>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:833e3100 r9:00000003 r8:851b1400 r7:20000140 r6:40946400 r5:851b1400 r4:00000000 [<8059bf68>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9b5fa8 to 0xdf9b5ff0) 5fa0: 00000000 00000000 00000003 40946400 20000140 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 003462d8 003462e4 5fe0: 7efe2790 7efe2780 00018e58 001307a0 r10:00000036 r9:833e3100 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