8<--- cut here --- Unable to handle kernel paging request at virtual address fee00004 when write [fee00004] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 24886 Comm: syz.8.3740 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 : [<8148f8d4>] lr : [<8148f8c4>] psr: 60000013 sp : dfc1dd30 ip : dfc1dd30 fp : dfc1dd54 r10: 82d30dfc r9 : 00000003 r8 : 84296840 r7 : dfc1dd90 r6 : 84296840 r5 : 00000000 r4 : 00000000 r3 : fee00004 r2 : 81e2dc88 r1 : 00000001 r0 : 8148f534 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 890a2fc0 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 84296840 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfc1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r8 information: slab kmalloc-192 start 84296840 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 0xdfc1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Register r12 information: 2-page vmalloc region starting at 0xdfc1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2747 Process syz.8.3740 (pid: 24886, stack limit = 0xdfc1c000) Stack: (0xdfc1dd30 to 0xdfc1e000) dd20: ffffffff 00000004 82bd8e44 82bd8e44 dd40: 81e2e148 00000000 dfc1dd8c dfc1dd58 8148b450 8148f75c 40946400 00000000 dd60: dfc1dd7c 20000600 84296840 b5403587 40946400 00000003 00000003 89e8d5c0 dd80: dfc1de4c dfc1dd90 81486c54 8148b354 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00000004 00000000 00000005 0000000c 00000008 00000006 00100002 ddc0: 00000007 00000005 00000100 00000004 00000001 00000001 00000009 00000000 dde0: 00000101 00000083 80000000 00000003 00001b1c 0000000c 00000004 00000000 de00: ffffffff 0000000b 00000004 0000003b 0000000c 10000006 00000010 fffffff8 de20: 00000000 6d6aad66 00000000 8614e000 84296840 20000600 40946400 00000003 de40: dfc1df14 dfc1de50 81487f7c 81486b94 00000000 6d6aad66 00000000 00000000 de60: 8254880c dfc1dea4 0000005f 8437af18 00000064 84296870 dfc1dee4 dfc1de88 de80: 808037c4 807f9af4 00000064 00000001 00000000 dfc1dea4 88d55210 83428550 dea0: 00006400 0000000b dfc1de98 00000000 00000000 6d6aad66 00000000 8614e000 dec0: 40946400 20000600 20000600 8614e000 00000003 89e8d5c0 dfc1def4 dfc1dee8 dee0: 808038f8 6d6aad66 dfc1df14 00000000 8614e001 40946400 20000600 8614e000 df00: 00000003 89e8d5c0 dfc1dfa4 dfc1df18 805ba870 81487c34 ecac8b10 89e8d5c0 df20: dfc1df3c dfc1df30 81b52fc0 81b52e8c dfc1df54 dfc1df40 8025a7ac 8028e488 df40: dfc1dfb0 40000000 dfc1df84 dfc1df58 80220bdc 8025a768 00000000 82a1eb0c df60: dfc1dfb0 0013e9c0 ecac8b10 80220b30 00000000 6d6aad66 dfc1dfac 00000000 df80: 00000000 00346310 00000036 8020029c 89e8d5c0 00000036 00000000 dfc1dfa8 dfa0: 80200060 805ba638 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76feb0dc dfe0: 76feae88 76feae78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<8148f750>] (parport_attach) from [<8148b450>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e148 r4:82bd8e44 [<8148b348>] (comedi_device_attach) from [<81486c54>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:89e8d5c0 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:84296840 r4:20000600 [<81486b88>] (do_devconfig_ioctl) from [<81487f7c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000600 r5:84296840 r4:8614e000 [<81487c28>] (comedi_unlocked_ioctl) from [<805ba870>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81487c28>] (comedi_unlocked_ioctl) from [<805ba870>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81487c28>] (comedi_unlocked_ioctl) from [<805ba870>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81487c28>] (comedi_unlocked_ioctl) from [<805ba870>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:89e8d5c0 r9:00000003 r8:8614e000 r7:20000600 r6:40946400 r5:8614e001 r4:00000000 [<805ba62c>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfc1dfa8 to 0xdfc1dff0) dfa0: 00000000 00000000 00000003 40946400 20000600 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76feb0dc dfe0: 76feae88 76feae78 00018ebc 00130820 r10:00000036 r9:89e8d5c0 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