8<--- cut here --- Unable to handle kernel paging request at virtual address fee00078 when write [fee00078] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 21711 Comm: syz.6.3351 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:99 [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 : [<81492254>] lr : [<81492244>] psr: 60000013 sp : dfacdd30 ip : dfacdd30 fp : dfacdd54 r10: 82d30dfc r9 : 00000003 r8 : 8315a9c0 r7 : dfacdd90 r6 : 8315a9c0 r5 : 00000000 r4 : 00000000 r3 : fee00078 r2 : 81e2dc68 r1 : 00000001 r0 : 81491eb4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 87f8ec40 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 8315a9c0 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfacc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r8 information: slab kmalloc-192 start 8315a9c0 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 0xdfacc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xdfacc000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.6.3351 (pid: 21711, stack limit = 0xdfacc000) Stack: (0xdfacdd30 to 0xdface000) dd20: ffffffff 00000004 82bd8e44 82bd8e44 dd40: 81e2e128 00000000 dfacdd8c dfacdd58 8148ddcc 814920dc 40946400 00000000 dd60: dfacdd7c 20000600 8315a9c0 b5403587 40946400 00000003 00000003 8676ee40 dd80: dfacde4c dfacdd90 814895d0 8148dcd0 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00000078 00000000 00000000 0000000c 00000008 00000006 00100002 ddc0: 00000007 00000005 00000100 00000004 00000001 00000001 00020003 00000000 dde0: 00000101 00000083 80000000 00000003 00001b18 00000016 00000004 00000000 de00: ffffffff 0000000b 00000004 0000003b 0000000c 10000006 00000664 fffffff8 de20: 00000000 6331e729 00000000 860e9c80 8315a9c0 20000600 40946400 00000003 de40: dfacdf14 dfacde50 8148a8f8 81489510 00000000 6331e729 00000000 00000000 de60: 8254980c dfacdea4 0000005f 842225e0 00000064 8315a9f0 dfacdee4 dfacde88 de80: 80805b6c 807fbe9c 00000064 00000001 00000000 dfacdea4 8693bb10 8341c2a8 dea0: 00006400 0000000b dfacde98 00000000 00000000 6331e729 00000000 860e9c80 dec0: 40946400 20000600 20000600 860e9c80 00000003 8676ee40 dfacdef4 dfacdee8 dee0: 80805ca0 6331e729 dfacdf14 00000000 860e9c81 40946400 20000600 860e9c80 df00: 00000003 8676ee40 dfacdfa4 dfacdf18 805bab08 8148a5b0 ecac8b10 8676ee40 df20: dfacdf3c dfacdf30 81b56440 81b5630c dfacdf54 dfacdf40 8025a7a4 8028e480 df40: dfacdfb0 40000000 dfacdf84 dfacdf58 80220bdc 8025a760 00000000 82a1eb0c df60: dfacdfb0 0013e9c0 ecac8b10 80220b30 00000000 6331e729 dfacdfac 00000000 df80: 00000000 00356310 00000036 8020029c 8676ee40 00000036 00000000 dfacdfa8 dfa0: 80200060 805ba8d0 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76faf0dc dfe0: 76faee88 76faee78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<814920d0>] (parport_attach) from [<8148ddcc>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e128 r4:82bd8e44 [<8148dcc4>] (comedi_device_attach) from [<814895d0>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:8676ee40 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:8315a9c0 r4:20000600 [<81489504>] (do_devconfig_ioctl) from [<8148a8f8>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000600 r5:8315a9c0 r4:860e9c80 [<8148a5a4>] (comedi_unlocked_ioctl) from [<805bab08>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148a5a4>] (comedi_unlocked_ioctl) from [<805bab08>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148a5a4>] (comedi_unlocked_ioctl) from [<805bab08>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148a5a4>] (comedi_unlocked_ioctl) from [<805bab08>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8676ee40 r9:00000003 r8:860e9c80 r7:20000600 r6:40946400 r5:860e9c81 r4:00000000 [<805ba8c4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfacdfa8 to 0xdfacdff0) dfa0: 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76faf0dc dfe0: 76faee88 76faee78 00018ebc 00130820 r10:00000036 r9:8676ee40 r8:8020029c r7:00000036 r6:00356310 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