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: 5413 Comm: syz.0.430 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP 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 : [<814585a4>] lr : [<81458594>] psr: 60000013 sp : dfab1d30 ip : dfab1d30 fp : dfab1d54 r10: 82d2cdc4 r9 : 00000003 r8 : 842adcc0 r7 : dfab1d90 r6 : 842adcc0 r5 : 00000000 r4 : 00000000 r3 : fee00100 r2 : 81e27508 r1 : 00000001 r0 : 81458204 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86355880 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 842adcc0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfab0000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r8 information: slab kmalloc-192 start 842adcc0 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 0xdfab0000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Register r12 information: 2-page vmalloc region starting at 0xdfab0000 allocated at kernel_clone+0xbc/0x43c kernel/fork.c:2721 Process syz.0.430 (pid: 5413, stack limit = 0xdfab0000) Stack: (0xdfab1d30 to 0xdfab2000) 1d20: 824bc51c 842adcc0 00000000 82bd2aa0 1d40: 81e279c8 00000000 dfab1d8c dfab1d58 81454104 8145842c 40946400 00000000 1d60: dfab1d7c 20000180 842adcc0 b5403587 40946400 00000003 00000003 840ad780 1d80: dfab1e4c dfab1d90 8144f910 81454008 656d6f63 705f6964 6f707261 00007472 1da0: 00000000 00000100 0000000f 000000d1 00000002 00000000 00000100 00000003 1dc0: 20000000 00000008 0000000c 00000000 00000b51 00000001 00000401 00010001 1de0: 00000001 01000000 00000008 00000fe8 00000401 80000000 00000002 00000007 1e00: 00000009 00000048 00000009 00000006 00006a77 00000002 00000008 0000000a 1e20: 00000000 80c6985a 00000000 838a6f80 842adcc0 20000180 40946400 00000003 1e40: dfab1f14 dfab1e50 81450c34 8144f848 00000000 80c6985a 00000000 00000000 1e60: 82530804 dfab1ea4 0000005f 845cef18 00000064 842adcf0 dfab1ee4 dfab1e88 1e80: 807e9510 807df824 00000064 00000001 00000000 dfab1ea4 833653d0 83441110 1ea0: 00006400 0000000b dfab1e98 00000000 00000000 80c6985a 00000000 838a6f80 1ec0: 40946400 20000180 20000180 838a6f80 00000003 840ad780 dfab1ef4 dfab1ee8 1ee0: 807e9644 80c6985a dfab1f14 00000000 838a6f81 40946400 20000180 838a6f80 1f00: 00000003 840ad780 dfab1fa4 dfab1f18 805a188c 814508ec ecac8b10 840ad780 1f20: dfab1f3c dfab1f30 81b15d14 81b15be0 dfab1f54 dfab1f40 8025a694 8028e1b4 1f40: dfab1fb0 40000000 dfab1f84 dfab1f58 80220be0 8025a650 00000000 82a1c63c 1f60: dfab1fb0 0013e940 ecac8b10 80220b34 00000000 80c6985a dfab1fac 00000000 1f80: 00000000 00346310 00000036 8020029c 840ad780 00000036 00000000 dfab1fa8 1fa0: 80200060 805a1654 00000000 00000000 00000003 40946400 20000180 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f520dc 1fe0: 76f51e88 76f51e78 00018e58 001307a0 60000010 00000003 00000000 00000000 Call trace: [<81458420>] (parport_attach) from [<81454104>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e279c8 r4:82bd2aa0 [<81453ffc>] (comedi_device_attach) from [<8144f910>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:840ad780 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:842adcc0 r4:20000180 [<8144f83c>] (do_devconfig_ioctl) from [<81450c34>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000180 r5:842adcc0 r4:838a6f80 [<814508e0>] (comedi_unlocked_ioctl) from [<805a188c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814508e0>] (comedi_unlocked_ioctl) from [<805a188c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814508e0>] (comedi_unlocked_ioctl) from [<805a188c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814508e0>] (comedi_unlocked_ioctl) from [<805a188c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:840ad780 r9:00000003 r8:838a6f80 r7:20000180 r6:40946400 r5:838a6f81 r4:00000000 [<805a1648>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfab1fa8 to 0xdfab1ff0) 1fa0: 00000000 00000000 00000003 40946400 20000180 00000000 1fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f520dc 1fe0: 76f51e88 76f51e78 00018e58 001307a0 r10:00000036 r9:840ad780 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