8<--- cut here --- Unable to handle kernel paging request at virtual address fee0007c when write [fee0007c] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 14519 Comm: syz.5.2015 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 : [<81493794>] lr : [<81493784>] psr: 60000013 sp : dfdedd30 ip : dfdedd30 fp : dfdedd54 r10: 82d30dfc r9 : 00000003 r8 : 8315ab40 r7 : dfdedd90 r6 : 8315ab40 r5 : 00000000 r4 : 00000000 r3 : fee0007c r2 : 81e2dee8 r1 : 00000001 r0 : 814933f4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86561940 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 8315ab40 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfdec000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r8 information: slab kmalloc-192 start 8315ab40 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 0xdfdec000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xdfdec000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.5.2015 (pid: 14519, stack limit = 0xdfdec000) Stack: (0xdfdedd30 to 0xdfdee000) dd20: 824d49b8 8315ab40 82bd8ea0 82bd8ea0 dd40: 81e2e3a8 00000000 dfdedd8c dfdedd58 8148f310 8149361c 40946400 00000000 dd60: dfdedd7c 20000600 8315ab40 b5403587 40946400 00000002 00000003 850ad5c0 dd80: dfdede4c dfdedd90 8148ab14 8148f214 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 0000007c 00000005 00000000 0000000c 00000012 00000006 00100002 ddc0: 00000007 00000005 00000100 00000004 00000001 00000001 00020003 352216e9 dde0: 00000008 00000083 00800007 01000003 00001b18 00000018 00000000 ffffffff de00: ffffffff 0000000b fffffff9 0000003b 0000080c 0800099d 00000664 fffffff8 de20: 00000000 ac325c57 00000000 862bd380 8315ab40 20000600 40946400 00000002 de40: dfdedf14 dfdede50 8148be3c 8148aa54 00000000 ac325c57 00000000 00000000 de60: 8254980c dfdedea4 0000005f 841fddd8 00000064 8315ab70 dfdedee4 dfdede88 de80: 80806188 807fc404 00000064 00000001 00000000 dfdedea4 84f1a010 834f6908 dea0: 00006400 0000000b dfdede98 00000000 00000000 ac325c57 00000000 862bd380 dec0: 40946400 20000600 20000600 862bd380 00000003 850ad5c0 dfdedef4 dfdedee8 dee0: 808062bc ac325c57 dfdedf14 00000000 862bd381 40946400 20000600 862bd380 df00: 00000003 850ad5c0 dfdedfa4 dfdedf18 805bab28 8148baf4 ecac8b10 850ad5c0 df20: dfdedf3c dfdedf30 81b58240 81b5810c dfdedf54 dfdedf40 8025a7a8 8028e490 df40: dfdedfb0 40000000 dfdedf84 dfdedf58 80220bdc 8025a764 00000000 82a1eb0c df60: dfdedfb0 0013e9c0 ecac8b10 80220b30 00000000 ac325c57 dfdedfac 00000000 df80: 00000000 00356310 00000036 8020029c 850ad5c0 00000036 00000000 dfdedfa8 dfa0: 80200060 805ba8f0 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f910dc dfe0: 76f90e88 76f90e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81493610>] (parport_attach) from [<8148f310>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e3a8 r4:82bd8ea0 [<8148f208>] (comedi_device_attach) from [<8148ab14>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:850ad5c0 r9:00000003 r8:00000002 r7:40946400 r6:b5403587 r5:8315ab40 r4:20000600 [<8148aa48>] (do_devconfig_ioctl) from [<8148be3c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000002 r7:40946400 r6:20000600 r5:8315ab40 r4:862bd380 [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:850ad5c0 r9:00000003 r8:862bd380 r7:20000600 r6:40946400 r5:862bd381 r4:00000000 [<805ba8e4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfdedfa8 to 0xdfdedff0) dfa0: 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f910dc dfe0: 76f90e88 76f90e78 00018ebc 00130820 r10:00000036 r9:850ad5c0 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